Computing

multi-species

chemical

equilibrium

with

an

algorithm

based

on

the

reaction

extents

Computing

multi-species

chemical

equilibrium

with

an

algorithm

based

on

the

reaction

extents.

Computers

and

Chemical

Engineering,

58,[135][136][137][138][139][140][141][142][143].

A

mathematical

model

for

the

solution

of

a

set

of

chemical

equilibrium

equations

in

a

multi-species

and

multiphase

chemical

system

is

described.

The

computer-aid

solution

of

model

is

achieved

by

means

of

a

Newton-Raphson

method

enhanced

with

a

line-search

scheme,

which

deals

with

the

non-negative

constrains.

The

residual

function,

representing

the

distance

to

the

equilibrium,

is

defined

from

the

chemical

potential

(or

Gibbs

energy)

of

the

chemical

system.

Local

minimums

are

potentially

avoided

by

the

prioritization

of

the

aqueous

reactions

with

respect

to

the

heterogeneous

reactions.

The

formation

and

release

of

gas

bubbles

is

taken

into

account

in

the

model,

limiting

the

concentration

of

volatile

aqueous

species

to

a

maximum

value,

given

by

the

gas

solubility

constant.The

reaction

extents

are

used

as

state

variables

for

the

numerical

method.

As

a

result,

the

accepted

solution

satisfies

the

charge

and

mass

balance

equations

and

the

model

is

fully

compatible

with

general

reactive

transport

models.

In

a

system

at

chemical

equilibrium,

the

reactions

take

place

at

equal

rates

in

their

direct

and

reverse

directions

and,

therefore,

the

concentrations

of

the

reacting

substances

(reactants

and

products)

do

not

change

with

time.

The

chemical

equilibrium

assumption

(CEA)

consists

of

considering

that

all

the

species

in

the

system

have

time

enough

to

reach

the

equilibrium

state.

As

a

result,

the

time

derivative

of

the

chemical

equations

becomes

zero

and

a

set

of

algebraic

chemical

concentration

equations

can

be

used

to

mathematically

describe

such

a

system.

Despite

that,

the

equations

describing

multi-species

chemical

equilibrium

(MSCE)

systems

are

strongly

nonlinear

and

the

analytical

solution

cannot

be

found

except

for

the

most

simple

cases,

being

necessary

the

use

of

computer-aid

approaches..

Numerical

models

based

on

the

CEA

may

be

used,

for

example,

to:

fit

experimental

data

to

chemical

equilibrium

state

in

a

numerical

speciation

process,

to

estimate

trace

compounds

concentrations

based

on

the

analytical

measurements

of

species

with

significantly

higher

concentrations,

to

study

the

response

of

a

chemical

system

in

equilibrium

with

respect

to

external

changes,

to

study

weathering

mechanisms

in

geochemical

systems,

and

to

model

chemical

interactions

between

the

pore

solution

and

the

solid

matrix

in

porous

materials

(Bethke,

The

reliability

of

the

CEA

depends

on

the

time

scale

for

the

speciation

problem.

A

representative

example

would

be

a

reactive

transport

model

under

the

local

CEA

in

which

the

driving

forces

are

chemical

or

electrical

potential

gradients.

In

those

cases,

the

transport

rates

of

the

main

transport

mechanisms

(diffusion,

electromigration

and

electroosmosis)

are

slow

enough

to

accept

the

equilibrium

assumption

except

for

those

very

slow

heterogeneous

reactions

(Jacobs

Probstein,

Morel

Hering,

Aqueous

reversible

reactions

frequently

have

high

kinetic

rates

in

both

directions,

towards

the

products

and

towards

the

reactants,

making

the

CEA

acceptable

in

most

cases.

Acids

and

bases

dissociation

or

the

seft-ionization

of

water,

for

example,

can

reach

the

equilibrium

state

in

the

order

of

microseconds

or

even

faster.

Aqueous

complexation

reactions

are

also

usually

quite

fast,

normally

achieving

the

equilibrium

in

the

range

from

micro-to

milliseconds.

In

the

case

of

heterogeneous

reactions,

such

as

adsorption/desorption,

ion-exchange

or

precipitation/dissolution

reactions,

their

kinetic

rates

are

commonly

slower

than

the

above

mentioned

aqueous

homogeneous

reactions

and

their

rates

may

compete

with

the

transport

rates

in

some

cases..

Some

models

for

reactive

transport

through

porous

media

taking

into

consideration

the

kinetics

of

the

chemical

system

have

been

presented,

as

e.g.

(Johannesson,

Lichtner,

Steefel

Van

Cappellen,

Javadi

Al-Najjar,

Rubin,

Vereda-Alonso

et

al.,

Rate-controlled

equilibrium

models,

which

are

considered

more

realistic,

include

a

set

of

feasible

reactions

capable

to

reach

the

equilibrium

in

the

time

scale

of

the

transport

process

and

a

parallel

solution

of

the

kinetic

equations

for

the

slow

and/or

the

irreversible

reactions

(Koukkari

Pajarre,

Ribeiro

et

al.,

Steyer

et

al.,

The

most

accepted

mathematical

algorithm

for

MSCE

calculation

is

based

on

the

Morel's

Tableau

stoichiometric

method

(Morel

Hering,

Morel

Morgan,

which

basically

consists

in

dividing

the

set

of

chemical

species

in

a

number

of

master

species

(or

components)

and

secondary

species

(or

compounds).

Secondary

species

are

defined

as

a

combination

of

master

species

by

means

of

stoichiometric

chemical

equilibrium

equations.

In

(Reed,

and

(Bethke,

comprehensive

compilations

of

different

proposed

models

for

the

mathematical

solution

of

chemical

equilibrium

problems

can

be

found.

This

literature

review

will

not

be

repeated

here..

Several

computer

programs

for

MSCE

have

been

released.

Some

of

the

most

used

are

PHREEQC

(Parkhurst

Appelo,

PHREEQCi

(Charlton

et

al.,

(Ball

Nordstrom,

MINTEQ

(Peterson

et

al.,

(Wolery,

and

GEMS

(Remy,

Coupling

these

kind

of

stand-alone

programs

with

more

general

codes

for

different

purposes

is

possible.

Nevertheless,

exporting

and

importing

data

between

different

programs

normally

involves

the

participation

of

the

program

user,

as

well

as

significant

computational

time,

making

simulations

slow

or,

sometimes,

unfeasible.

Consequently,

the

implementation

of

tailor-made

codes

is

almost

always

necessary

for

more

complex

problems

(Rodriguez-Maroto

Vereda-Alonso,

In

summary,

numerical

strategies

for

computing

chemical

equilibrium

problems

are

classified

into

two

main

groups:

stoichiometric

and

non-stoichiometric

algorithms

(van

Baten

Szczepanski,

Blomberg

Koukkari,

Brassard

Bodurtha,

Carrayrou

et

al.,

Stoichiometric

algorithms

converge

on

the

solution

of

a

set

of

simultaneous

mass

balance

and

mass

action

equations

at

each

iteration,

while

non-stoichiometric

algorithms

aim

a

direct

minimization

of

the

Gibbs

energy

functions

of

the

chemical

species

constrained

by

mass

balances..

The

most

popular

stoichiometric

algorithm

uses

the

concentration

of

the

master

species

as

the

independent

state

variable

while

the

residual

function

to

be

minimized

in

the

numerical

procedure

is

defined

from

the

mass

balance

on

the

chosen

master

species

and

the

saturation

index

of

the

existing

solid

components.

The

mass

balance

of

protons

is

replaced

by

the

charge

balance

equation,

in

this

approach,

for

two

reasons:

to

avoid

considering

the

water

as

a

chemical

species

in

the

setup,

and

to

assure

charge

neutrality

in

the

equilibrated

solution.

This

method

has

shown

accurate

results

and

has

been

the

base

for

some

of

the

chemical

equilibrium

models

listed

above..

In

this

work,

we

propose

a

stoichiometric

method

for

MSCE,

based

on

the

Tableau's

concept,

iterating

on

the

reaction

extents

and

submitted

to

the

non-negative

composition

constraints.

Despite

this

method

shows

a

higher

tendency

of

falling

into

the

so-called

local

minima,

some

advantages

may

be

remarked:

A

model

based

on

the

reaction

extent

is

compatible

with

rate-controlled

models

dealing

simultaneously

with

chemical

equilibrium

and

chemical

kinetics,

and

for

a

given

value

of

the

reaction

extent,

the

mass

and

the

charge

conservation

principles

are

always

satisfied

increasing

the

compatibility

with

general

reactive-transport

models..

A

Newton-Raphson

(NR)

method,

enhanced

with

a

line-search

(LS)

with

backtracking

scheme,

is

used

for

the

solution

of

the

nonlinear

system

of

equations

(Press

et

al.,

Wolery

Walters,

The

model

includes

heterogeneous

precipitation/dissolution

reactions,

as

well

as

the

possibility

of

the

release

of

bubbles

of

volatile

aqueous

species

to

the

surrounding

atmosphere.

Logarithm

scale

is

used

in

order

to

convert

the

exponential

mass

action

equation

into

algebraical

equations,

assure

the

nonnegative

constrain,

and

to

minimize

the

error

induced

by

the

programing

language

when

using

values

with

significant

differences

in

their

orders

of

magnitude,

as

common

in

multi-species

chemical

systems.

A

method

for

computing

chemical

equilibrium

speciation

problems

has

been

described,

based

on

the

extent

of

each

chemical

reaction

of

the

system.

The

numerical

solution

method

is

based

on

a

quasi-NR

method

in

which

the

Jacobian

matrix

is

formed

by

a

numerical

technique

rather

than

being

calculated

analytically.

In

this

context,

a

vectorized

implementation

of

the

Jacobian

matrix

is

proposed

in

order

to

significantly

reduce

the

computational

time.

A

line

search

approach

is

used

to

deal

with

the

non-negative

concentrations

constraint

of

all

the

chemical

species..

The

presented

algorithm

is

designed

to

work

in

a

multispecies

and

multiphase

chemical

systems

under

the

assumption

of

chemical

equilibrium.

Problems

associated

with

local

minimums

are

potentially

avoided

by

the

prioritization

of

the

aqueous

reactions

with

respect

to

the

solid

dissolution

or

precipitation

reactions.

This

prioritization

method

is

based

on

the

assumption

that

that

the

kinetic

rates

of

reactions

involving

only

aqueous

species

are

faster

than

those

involving

solid

mineral

phases..

The

formation

of

gaseous

species

is

included

in

the

model

by

allowing

free

release

of

gas

bubbles

of

gaseous

species

when

those

bubbles

have

a

higher

pressure

than

the

surrounding

liquid

media

and

vapor

phase.

This

feature

limits

the

concentration

of

volatile

aqueous

species

to

a

maximum

value

given

by

the

gas

solubility

constant..

A

test

example

has

been

used

to

illustrate

the

main

features

of

the

model

presented

here.

The

use

of

the

extent

of

the

reactions

as

the

state

variable

makes

the

presented

algorithm

suitable

for

more

general

problems,

in

which

a

thorough

control

of

the

electrical

balance

is

required.

O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O B I O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Performance measurement: roles and challenges Purpose -The purpose of this paper is to identify the past and present practices, and the future roles of performance measurement in the Thai public sector. It is part of a transformation effort initiated by the Office of the Public Sector Development Commission (OPDC) on m-government -more mobile, responsive, and flexible government. The paper also aims to identify possible roadblocks from successfully integrating performance measurement into a management process. Design/methodology/approach -In-depth interviews with 12 executives and top administrators from private firms and public agencies, and document reviews are performed. The analysis on the participants' opinions is based on the applications of the grounded theory. The interview's findings are verified with document reviews. The roadblocks are identified and substantiated by two experts. Findings -For past and present practices, performance measurement is part of management tool and responsibility, a quality management system, and a learning organization. Its future viewpoints include a driver towards good governance, transparency, and accountability, and a success factor of performance audit and organizational competency/capability. Four important roadblocks in implementing performance measurement in an organization relate to staff empowerment, budgeting, external knowledge, and linkage with software usages. Practical implications -The findings provide important information into the OPDC's planning process on its m-government transformation initiative. Originality/value -The paper attempts to blend knowledge on performance measurement from both the private and public sectors. It highlights the greater roles and expectations on performance measurement in an organization. Performance measurement has gained more recognition from researchers and higher acceptance from practitioners over the last two decades (Neely, 1998; Try and Radnor, 2007; Hoque, 2008) . It has evolved from merely producing accounting-related to more comprehensive information that contains both financial and non-financial information (Wilson et al., 2003) . In addition, performance measurement is perceived to be a critical management tool that can help determine a success or a failure in both organizational and functional performance (Sink, 1985; Neely, 1998; Putu et al., 2007) Performance measurement typically provides feedback to the following three questions (Kurstedt, 1992; Neely, 1998; Liebowitz et al., 2007) . How well an organization is performing? Is the organization achieving its objectives? How much has the organization improved from a last period? In addition, performance measurement helps create feedback to managers on the effectiveness of improvement interventions as part of learning and development (Cohen and Levinthal, 1990; Liebowitz, 2004) . In general, performance measurement represents a system that consists of mechanisms, processes, and criteria or areas of performance (Sink and Tuttle, 1989; Dixon et al., 1990; Kaplan and Norton, 1996; Neely, 2002) . It needs to be aligned with organizational missions, policies, and objectives (Kaplan and Norton, 2004; Pongatichat and Johnston, 2008) . Attributes that constitute performance areas such as quality and productivity have to be identified. For examples, the maintenance function impacts production disruption, equipment useful lives, and cost, etc. These represent the attributes for measuring the quality performance. It is also important to note that the standards or the benchmarks are typically set through performance measurement (Talluri and Sarkis, 2002) . Finally, information visibility and persistent communication throughout an organization helps allow management to contribute where appropriate (Vokurka, 2004) .. Despite the strong recognition of its impacts on a management process, performance measurement, especially at the organizational and functional levels, sometimes have no received proper attention from top management. This lack of attention may stem from the premise suggested by Kurstedt (1992) that a manager had typically relied on information and experiences when making decisions ( Figure 1 ). As a result, experiences may overshadow the importance of performance information. In addition, most managers have traditionally paid a lot of attention to financial information (Sumanth, 1998 ). The reason is that they have to be accountable to shareholders who are mainly interested in financial performance and returns of a firm. Nevertheless, performance measurement has begun to play more influential roles in process management within a company as the database becomes more flexible and robust (Kouzmin et al., 1999; Rich, 2007) . This is due to the advancement in information and communication technology.. Specifically, for the performance-criteria component, a ratio format is preferred for key performance indicators in order to normalize information (Sink and Tuttle, 1989 ). The ratio format has been proven to be helpful for external comparisons such as comparison with industrial averages and benchmarking (Kouzmin et al., 1999) . In cases of the changes in operations such as acquisition of new plants or expansion of production lines, the quality of information for performance analysis is not compromised. For examples, with a new plant acquisition, the use of revenue alone may not be appropriate since the increase is likely due to this takeover (instead of operational improvement). Finally, it should be noted that the portrayal of information could be in either the tabular or the graphical formats.. To better utilize performance information, Sink and Tuttle (1989) advocated the extensive use of both quantitative and qualitative data with clear definitions and specific frequency for reviews. This is quite helpful for data collection and reporting efforts. For examples, different managers may interpret the term revenue differently. For some, revenue implies cash plus account receivables. For others, revenue indicates cash and future receivable amounts subtracted returns. In addition, the dimensional units must also be stated. The term labor has at least three dimensions, i.e. time (hours), headcounts (persons), and financial value (dollars). The term maintenance may be collected in various dimensional units such as frequency (times), cost (dollars), and headcounts (persons), and time (hours). The specific frequency of review (daily, weekly, monthly, quarterly, and so on) is helpful for reporting. Finally, Hoehn (2003) pointed out the need to recognize different weights when measuring performance. This can be attributed to, for example, to the selling price.. Gradually, performance measurement has been recognized for its unique applications when dealing with different objects or domains. For examples, a method used for measuring blue-collar performance (e.g. standard time from motion study) cannot be applied at the functional level or for white-collar workforce (Barnes, 1980) . On the other hand, the technique for measuring white-collar workforce's performance, introduced by Zigon (1998) with the integration of a customer diagram, cannot be utilized for evaluating production-line workers' performance. In addition, a method for measuring equipment's performance (e.g. utilization and effectiveness) cannot be directly adapted for the organizational level (Sink, 1985) . The method for measuring financial performance (e.g. return on assets, profit margin, earning per share) cannot be entirely utilized at the plant level which focuses primarily on yield, equipment downtime, work stoppages, and inventory turnover (Harper, 1984) .. To highlight unique application of performance measurement, the productivity perspective is used for this demonstration. Specifically, when focusing on the industrial, national, and international levels, many approaches have been designed by (Duke and Torres, 2005; Meyer and Harper, 2005) . At the organizational, functional, program, and project levels, there have been several concepts and ideas involving in the measurement/assessment work. Harper (1984) also developed a performance measurement framework at the organizational/functional levels. Other frameworks and methods at the organizational/functional level include multi-factor productivity measurement model and value-added productivity (Sink, 1985) . At the group and individual levels, there were many concepts such as motivational methods based on industrial psychologists and performance appraisals for salary structure/workload analysis extended by human resource specialists, and piece-rate/standard times determined by industrial engineers (Sumanth, 1998) . Interestingly, the term performance has included many conceptual frameworks. For examples, Sink and Tuttle (1989) argued that the term performance consisted of profitability, productivity, quality of work life, innovation, effectiveness, efficiency, and quality. On the other hand, Harper (1984) , suggested that there are seven areas when measuring performance. Included are:. (1) productivity; (2) unit cost; (3) price; (4) factor proportion; (5) cost proportion; (6) product mix; and (7) input allocation.. There are also other concepts that are more practical such as the balanced scorecard where performance needs to have information from financial, customer, internal business processes, and innovation and learning areas (Kaplan and Norton, 1996) . Neely (2002) also suggested that the concept of performance prism with different facets for required information. Performance measurement's impacts on the effectiveness of management and the sustainability on continuous improvement can be highlighted by Deming (1986) . He summarized that it would difficult to manage without performance measurement. In addition, some of the most recognized early year research outputs from the American Productivity and Quality Center (formally known as American Productivity Center) include measurement-related frameworks such as multi-factor productivity measurement model (Sink and Tuttle, 1989) . To signify its important status in a management process, the term performance measurement is explicitly recognized in the Malcolm Baldrige award -performance measurement, analysis, and knowledge management (Vokurka, 2004; Edvardsson and Enguist, 2006) . Furthermore, ISO 9001: 2008 clearly specifies performance measurement as part of its requirement no. 8 -performance measurement, analysis, and improvement. Even the European Foundation for Quality Management Excellence Model contains the critical component, so-called the key performance results, including business, people, customer, and society areas.. Gradually, instead of focusing primarily on shareholders, the term stakeholders become more imminent (Goldsmith and Eggers, 2004; Mettanen, 2005; Steiner, 2008) . Other corresponding trends relating to the increasing importance of stakeholders have included corporate citizenship and governance (Eggers, 2005and see Table I for an overview of performance measurement). The study, based on the project with the OPDC, aims to identify the past/present and the future roles of performance measurement. This study is part of an overall effort to transform public agencies into m-government -more responsive and flexible government. Performance measurement is chosen to be one of the four key features in this transformation effort. From the viewpoints of past and present practices, performance measurement is part of management tool and responsibility, a quality management system, and a learning organization. The future viewpoints on performance measurement include a driver towards good governance, transparency, and accountability, and an integral part of performance audit and organizational competency/capability. In addition, this study identifies and describes four important roadblocks in implementing performance measurement in an organization. These roadblocks relate to staff empowerment, budgeting, external knowledge, and linkage with software usages. The identification of the four roadblocks is critical for the OPDC's planning on performance measurement. seminars and workshops for several international governments, including Australia, India, Japan, and Thailand.. The second expert, Dr William K. Hoehn, has conducted several research projects in the areas of performance measurement. He has often used performance measurement as the first step to build a strong management system when companies need to gain confidence and recognition from their clients, especially in the defense-related industries. He has worked in many countries such as the USA and Japan in building a robust performance measurement for a strong management system. Dr Hoehn has also given speeches and lectures relating to performance management in several countries, including Thailand. The literatures relating the applications and integrations of performance measurement into an organization are initially reviewed. The policy statements and official documents from as well as new initiatives by key private associations (e.g. Federation of Thai Industries) and agencies in charge of public sector reforms (e.g. the OPDC, the Budget Bureau, and Ministry of Finance) are carefully examined. Information background and the rational relating to performance-measurement initiatives are cautiously studied. The interviews are conducted with top executives and administrators from the total of 12 organizations (Appendix 1). Six leading private firms and six well-recognized public agencies have participated in this study. The discussions primarily focus on their viewpoints, and past and current policies, objectives, initiatives, and activities relating to performance measurement. Their comments are recorded and later This task adapts the concept from the grounded theory on attempting to group various and diverse data into a common code (Strauss, 1987; Goulding, 2002) . This code represents repeated assertions during the interviews in the consensus manner. It is important to point out that there are other descriptions relating to performance measurement. It was deemed to be a tool to help determine reward and recognition. It was earlier perceived to be a tool to identify potential operational areas to be contracted out. However, it was eventually viewed that the roles of performance measurement in the above two manners was not entirely appropriate. Appraisal and outsourcing were too complex and political. Some of the details can be described as follows.. For the opinions expressed by participants from the private sector, they have addressed performance measurement as a necessary tool for successful management. They perceived this term as a representation of a new managerial style in the workplace. From their viewpoint, performance measurement is an important part of ISO 9001: 2008. Performance measurement helps bring more scientific analysis into a decision-making process. Other significant comments can be summarized as follows. Performance measurement underlines the change towards management by information and knowledge instead of primarily relying on experiences and judgment. It signifies one of the desirable outcomes from recent investment in information and communication technology. It should be worked and utilized together with a current accounting system. In addition, due to the recent promotion of Thailand Quality Award (similar to the US Malcolm Balrige National Quality Award), more attention has been paid to the development and deployment of performance measurement. It is strongly related to knowledge management as information from performance measurement should be shared and communicated throughout an organization. Learning from past mistakes is made possible with performance measurement.. For the public sector, performance measurement is mandated as part of a performance agreement between an agency's head and his/her superior. This requirement is part of an effort to integrate a four-year strategic plan with annual performance goals and targets into a management process within individual agencies. Performance measurement helps bring new terms and concepts such as efficiency, productivity, and quality into day-to-day operations. Furthermore, it is important to recognize that, for the public sector, the OPDC in cooperation with Thailand Productivity Center have promoted the Public Sector Quality Management Award to improve the quality of services delivered by public agencies in Thailand. In addition, both the Budget Bureau and Ministry of Finance have encouraged public agencies to develop performance measurement that is unique in order to monitor and evaluate the progress of an organization. The summary of the viewpoints on past and present descriptions in regard to performance measurement is as follows (Table II) .. It should be noted that, based on the first part of the interviews, the level of complexity on the roles of performance measurement from the past to the present appear to increase gradually. Performance measurement-related tasks such as identifying an appropriate set of key performance indicators, revising and modifying this set at least on the annual basis, and setting and communicating the target levels based on these indicators represents fundamental responsibilities of top management. It also is regarded as an important management tool to help direct an organization and/or an operation. Progressively, it becomes an integral part of a quality management system. Finally, it is considered as a foundation for a learning organization. In other words, the implications of performance measurement have turned out to become broader and more far-reaching (Figure 4) . The next stage of the interview is more challenging. It involves future viewpoints on the roles of performance management. The interviews, with the same group of top management, reveal many remarkable thoughts on the emerging importance and future roles of performance measurement. Despite the fact that some comments may be conceptual and abstract, they are helpful in visualizing the future shape and form of performance measurement. Interestingly, their viewpoints are not as diverse as anticipated. It appears that participants center their opinions, based on past experiences and familiarity with international practices (Table III) .. It is important to note that participants generally agree that performance measurement will become more important and will imply how well an organization or a functional unit is managed -high performance with openness to all stakeholders. It is expected to be one of the focal points in an organization for external stakeholders (as part of audits -manufacturers and suppliers for contractual partnership, and citizen groups and agencies for public spending). Apparently, performance measurement largely reflects professionalism and competency of top management ( Figure 5 ). This study adapts the grounded theory as the crucial component of its research methodology (Strauss, 1987) . The data collection is based on document reviews and interviews. The key points from these reviews and interviews are to be analyzed by developing and assigning the key terms or codes (Strauss, 1987; Goulding, 2002) . These codes are determined by the frequency brought up during the interviews. Afterwards, the general ideas that are based on these codes are established as a basis for understanding the trends of performance measurement. To ensure that the identified trends are acceptable, further international comparisons (based on document reviews) with specific cases and initiatives in the USA and Europe are conducted. Finally, the discussion with the experts in the areas of performance measurement helps identify the future challenges for performance measurement (Figure 3 ).

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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The Frobenius anatomy of word meanings I: subject and object relative pronouns Abstract. This paper develops a compositional vector-based semantics of subject and object relative pronouns within a categorical framework. Frobenius algebras are used to formalise the operations required to model the semantics of relative pronouns, including passing information between the relative clause and the modified noun phrase, as well as copying, combining, and discarding parts of the relative clause. We develop two instantiations of the abstract semantics, one based on a truth-theoretic approach and one based on corpus statistics. Ordered algebraic structures and sequent calculi have been used extensively in Computer Science and Mathematical Logic. They have also been used to formalise and reason about natural language. Lambek (1958) [17] used the ordered algebra of residuated monoids to model grammatical types, their juxtapositions and reductions. Relational words such as verbs have implicative types and are modelled using the residuals of the monoid multiplication [23, 24] . Later, Lambek (1999) [18] simplified these algebraic calculi in favour of pregroups. Here, there are no binary residual operations, but each element of the algebra has a left and a right residual or adjoint.. In terms of semantics, pregroups do not naturally lend themselves to a modeltheoretic treatment [22] . However, pregroups are suited to a radically different treatment of semantics, namely distributional semantics [27] . Distributional semantics uses vector spaces based on contextual co-occurrences to model the meanings of words. Coecke et al. (2010) [8] show how a compositional semantics can be developed within a vector-based framework, by exploiting the fact that vector spaces with linear maps and pregroups both have a compact closed categorical structure [15, 25] . Some initial attempts at implementation include Grefenstette and Sadrzadeh (2011a) [10] and Grefenstette and Sadrzadeh (2011b) [11] .. One problem with the distributional approach is that it is difficult to see how the meanings of some words -e.g. logical words such as and, or, and relative pronouns such as who, which, that, whose -can be modelled contextually. Our focus in this paper is on relative pronouns in the distributional compositional setting.. The difficulty with pronouns is that the contexts in which they occur do not seem to provide a suitable representation of their meanings: pronouns tend to occur with a great many nouns and verbs. Hence, if one applies the contextual co-occurrence methods of distributional semantics to them, the result will be a set of dense vectors which do not discriminate between different meanings. The current state-of-the-art in compositional distributional semantics either adopts a simple method to obtain a vector for a sequence of words, such as adding or mutliplying the contextual vectors of the words [20] , or, based on the grammatical structure, builds linear maps for some words and applies these to the vector representations of the other words in the string [2, 10] . Neither of these approaches produce vectors which provide a good representation for the meanings of relative clauses.. In the grammar-based approach, one has to assign a linear map to the relative pronoun, for instance a map f as follows: However, it is not clear what this map should be. Ideally, we do not want it to depend on the frequency of the co-occurrence of the relative pronoun with the relevant basis vectors. But both of the above mentioned approaches rely heavily on the information provided by a corpus to build their linear maps. The work of Baroni and Zamparelli (2010) [2] uses linear regression and approximates the context vectors of phrases in which the target word has occurred, and the work of Grefenstette and Sadrzadeh (2011a) [10] uses the sum of Kronecker products of the arguments of the target word across the corpus. The semantics we develop for relative pronouns and clauses uses the general operations of a Frobenius algebra over vector spaces [7] and the structural categorical morphisms of vector spaces. We do not rely on the co-occurrence frequencies of the pronouns in a corpus and only take into account the structural roles of the pronouns in the meaning of the clauses. The computations of the algebra and vector spaces are depicted using string diagrams [12] , which depict the interactions that occur among the words of a sentence. In the particular case of relative clauses, they visualise the role played by the relative pronoun in passing information between the clause and the modified noun phrase, as well as copying, combining, and even discarding parts of the relative clause.. We develop two instantiations of the abstract semantics, one based on a truth-theoretic approach, and one based on corpus statistics, where for the latter the categorical operations are instantiated as matrix multiplication and vector component-wise multiplication. As a result, we will obtain the following for the meaning of a subjective relative clause:. The rest of the paper introduces the categorical framework, including the formal definitions relevant to the use of Frobenius algebras, and then shows how these structures can be used to model relative pronouns within the compositional vector-based setting.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Activity Theory as a means for multi-scale analysis of the engineering design process: A protocol study of design in practice This paper contributes to improving our understanding of design activity. Specifically the paper uses Activity Theory to enable a multi-scale analysis of the activity of three engineering designers over a period of one month. Correspondingly, this paper represents the first work that explicitly investigates design activity across different scales, referred to as macro-, meso- and micro-scales. In addition to establishing the range of activities and tasks that occur at, and constitute, each scale the underlying relationships between the scales of activity are discussed. Further, the paper elucidates the wider implications of the proposed framework and its findings for both design research and practice. Central to these implications is the articulation of design as a complex fabric of interwoven processes. This work has identified and started to address the gap in research associated with bridging the macro and micro--scale processes in design activity. In order to investigate this an observational study was explored using a detailed protocol analysis. The method used can be summarised as:. • Observe designer activity using a number of overlapping capture sources as well as contextualising the wider situation.. • Code and analyse the data at each scale (macro, meso, and micro) in order to identify processes scales.. • Consider cross--scale analysis in order to trace the relationships between the embedded processes.. The reported study built on the assumption that Activity Theory could be used as a new perspective for describing design work as parallel embedded activities across distinct scales. To explore this proposition the conceptual framework of Activity Theory was adapted to describe design work (activities, tasks, and actions) and provide a coherent structure for coding of design work at different scales. The developed framework and coding scheme was applied to a protocol study of three designers over a period of 1 month each. The proposed approach provided a substantially different insight into the study data than previous mono--scalar approaches. In particular, it offered significant new insight into the distinct scales and the interplay between the various processes involved in design work - something not previously described in the literature.. Here design work was found to align with no single process but instead constitute a number of embedded processes, which can be considered to occur over three scales: micro--, meso--and macro--. Further, these processes were found to have embedded relations across scales. This latter element, in particular, serves to support the existing results and helps to confirm the proposed research framework describing design activity as a multi--scale interweaving of processes. Although significant further work is required in order to explicitly define the full extent of these relationships the need to consider multiple scales in design studies is clear. Although there are a number of limitations associated with this work the findings presented here hold significant implications and potential for both pure design researchers, and those seeking to support design in practice. In particular, the findings of this study present some important implications for the development of design theory and the need for a number of complementary theoretical models in order to cohesively describe the complex multi--faceted interweaving of processes. Further, the distribution of tasks highlights the fact that all aspects of design are represented across the design process stages and thus have implications for how researchers target design support tools.. This also points to future research opportunities. In particular there is a need to further explore and decompose the various processes and their manifestation at the different scales of analysis.. This should also be accompanied with design specific theory building. Explicitly targeting areas beyond the design artefact itself, and considering addition or development of models linking to, for example, organisational information processing, design, and decision--making. There is also scope for expanding the link between micro--scale design actions and macro--scale manifestations of its affect in the wider design process.. Finally, we conclude by asserting that the ability to describe activity across scales affords a major opportunity for developing a richer more cohesive body of formal design theory, and expanding and linking together the current body of theory in design and its related fields. In order to empirically explore different scales of design activity and their interrelationship, two areas need first to be considered. These include how the different scales can be coherently considered in a single theoretical framework, and second, understanding how the different scales have been treated to date in design research. These two dimensions are considered in the following sections. Given the scope of this work, an observational approach was selected for two reasons. First, this approach complements and extends the scope of recent investigations of engineering design practice (Lethbridge et al., 2005) using, for example, work sampling and email logging approaches (M. A. Robinson, 2010; Wasiak et al., 2010) . Second, it provides for a rich insight into modern engineering design practice.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I


Talking Condition Recognition in Stressful and Emotional Talking Environments Based on CSPHMM2s This work is aimed at exploiting Second-Order Circular Suprasegmental Hidden Markov Models (CSPHMM2s) as classifiers to enhance talking condition recognition in stressful and emotional talking environments (completely two separate environments). The stressful talking environment that has been used in

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SECURE SMART CARD BASED PASSWORD AUTHENTICATION SCHEME WITH USER ANONYMITY Recently, a smart card based authentication and key agreement scheme preserving the user anonymity was proposed by Wang, Juang and Lei, that is designed to provide users with secure activities in ubiquitous computing environments. The authors proved that their scheme delivers important security properties and functionalities, such as without maintaining password/verification tables, freedom on password selection and alteration, mutual authentication, user anonymity, no time synchronization problem, key agreement implementation, forgery attack resistance and computation efficiency. However, we show that Wang et al.'s scheme has potential security flaws, which enable malicious attackers to counterfeit an application server to spoof the victim client and damage the security of session key and the property of user anonymity. In this paper, we propose an enhanced version of Wang et al.'s scheme to remedy these flaws. The proposed scheme not only ensures the merits of their scheme but also enhances the security of their scheme without raising any computation cost. The movement towards ubiquitous computing environment has raised a number of security concerns among the remote application servers and the login clients. At any time and any place, a client can access the desired services from an application server by using his/her mobile devices such as PDA, laptop and smart phone etc. Remote user authentication based on easy-to-remember passwords over insecure networks is the conventional method of authentication and has already been accepted warmly. An application server is responsible for managing and supplying network services to login clients for which password authentication schemes have been provided during a login request. A number of relevant researches and authentication mechanisms have been investigated in recent three decades and the key concepts include:. 1. Without maintaining verification or password tables in server side to prevent stolen verifier attacks [5, 7] . 2. Using a smart card to help clients to remember secret information [3] . 3. Users can freely choose and change passwords [2] . 4 . Resistance to password disclosure to any other users [17] [18] [19] [20] [21] [22] .. 5. Using a nonce-based mechanism to prevent time synchronization problem [9, 13] . 6. Resistance to replay, modification, parallel session [4] and password guessing attacks [14] . 7. Protect the system against impersonation attacks on both the user and the server side [1, 16] . 8. Low communication cost and computation complexity. 9. Achieve mutual authentication and key agreement implementation between login users and remote servers [10, 12, 15] . 10 . Prevention of smart card security breach attacks.. Note that secret information stored in a smart card can be extracted by analyzing and monitoring its power consumption [6, 20] . 11. Revocation of smart card in case of stolen or smart card loss problems [25] . 12. Provision of user anonymity and the client's identity and location cannot be traced by any users over public networks [8, 11, 23, 25] .. Recently, Wang et al. proposed a security enhancement on two efficient remote user authentication schemes using smart cards [24] . Remote user authentication scheme is a very important mechanism in distributed computer network systems for preventing unauthorized network access. Many remote user authentication schemes have been proposed using smart cards because of the low cost. In 2011, Wang et al. [25] found that the Wang et al.'s scheme is vulnerable to the known-key attack and the smart card loss problem. To remedy these weaknesses, they proposed an improvement on the Wang et al.'s scheme. However, we found that the Wang et al.'s scheme is still vulnerable to two kinds of sever counterfeit attacks and thus damage the security of session key. To resolve these security problems, we propose an enhanced version of Wang et al.'s scheme in this paper. The proposed scheme not only inherits the advantages of their scheme but also enhances the security of their scheme without raising any computation cost.. The remainder of this paper is organized as follows. A brief review of the Wang et al.'s scheme is given in Section 2. We analyze their scheme to show their security flaws in Section 3. In Section 4, we propose our improved scheme and the security analysis of the proposed scheme are presented in Section 5. Finally, we conclude this paper in Section 6. In this paper, we have showed security vulnerabilities on two Wang et al.'s password authentication schemes. By intercepting a victim client's login request, a malicious attacker can counterfeit an application server to spoof this victim client, endanger the security of key agreement, and damage the property of user anonymity. To resist these security threats found in their schemes, we have developed two enhanced password authentication schemes. Security analysis shows that two enhanced schemes not only inherit the merits of Wang et al.'s schemes but also enhance the security of Wang et al.'s schemes.

O B I O B I O O B I O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O O B I O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O


Tree-Based Data Broadcast in IEEE 802.15.4 and ZigBee Networks Abstract-This paper studies efficient and simple data broadcast in IEEE 802.15.4-based ad hoc networks (e.g., ZigBee). Since finding the minimum number of rebroadcast nodes in general ad hoc networks is NP-hard, current broadcast protocols either employ heuristic algorithms or assume extra knowledge such as position or two-hop neighbor table. However, the ZigBee network is characterized as low data rate and low cost. It cannot provide position or two-hop neighbor information, but it still requires an efficient broadcast algorithm that can reduce the number of rebroadcast nodes with limited computation complexity and storage space. To this end, this paper proposes self-pruning and forward node selection algorithms that exploit the hierarchical address space in ZigBee networks. Only one-hop neighbor information is needed; a partial list of two-hop neighbors is derived without exchanging messages between neighboring nodes. The ZigBee forward node selection algorithm finds the minimum rebroadcast nodes set with polynomial computation time and memory space. Using the proposed localized algorithms, it is proven that the entire network is covered. Simulations are conducted to evaluate the performance improvement in terms of the number of rebroadcast nodes, number of duplicated receivings, coverage time, and communication overhead.Index Terms-Broadcast, IEEE 802.15.4, ZigBee, ad hoc network.

O O B O B I O B O O O O O O O O B O O O O O O O B O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I B B I I


Development and evaluation of a terminology-based electronic nursing record system The present study was conducted to develop and evaluate a terminology-based electronic nursing record system. The narrative nursing notes of 63 obstetric patients collected over 395 hospital days were decomposed and cross-mapped with the Korean version of the beta version of the International Classification for Nursing Practice (ICNP). The terminology-based nursing record system was developed with a terminology server to manage nursing concepts and nursing phrases, and a user application system to document nursing notes. The system was evaluated in two Korean hospitals by 20 nurses documenting nursing notes of 57 patients. Patterns were found in nursing notes reflecting the nursing process. A total of 14,727 phrases were used for documenting nursing notes, with these phrases consisting of 237 unique phrases. Among the 259 unique nursing concepts extracted from the 237 unique phrases, 103 concepts (39.8%) did not map onto the ICNP. The users were able to find nursing phrases with a success rate of 89.4%. The mean time required for documentation at each input session decreased significantly from 276 to 158 s as the users became more experienced. In the past, patient records were merely a data repository that helped healthcare personnel to recall what they had done, whereas currently patient records play a role as a communication tool among healthcare personnel [1] . Computer-based patient records, which offer more accurate, accessible, and timely information compared to paper-based records, have been introduced as a strategy to maximize the usefulness of medical records [2] [3] [4] [5] . Traditional paper-based nursing records limit the utilization of patient data due to dispersion, inaccuracy, redundancy, disparity in the quality and frequency of records [6] , and missing data [7] . Furthermore, the lack of linkage with the records of other healthcare professionals means that nursing records are not being shared effectively. Many other healthcare professionals have little confidence in nursing records because they are not written in a systematic way and are often filled with redundant clinical laboratory test results or repetitive clinical information [8] . Thus, computerization of nursing records involves more than a simple automation of existing paper-based records. The records themselves must be changed so that data selection, mapping, coding schemas, identification of relations between data items, data searching, analysis processes, and the technology fit the information system paradigm [9] .. There are many potential problems-both qualitative and quantitative-when documenting services provided by nurses. Among these problems, nursing concepts and data standards that could support nursing practice are essential not only for the development of a nursing information system but also for developing other components of hospital information systems [10] . The past 10 years have seen progress in the development of nursing vocabularies taking place in parallel with the development of nursing information systems [11] [12] [13] [14] [15] . However, existing nursing vocabularies are inadequate due to lack of content coverage at the desired level of granularity, lack of consistent meanings for concepts and their relationships, and lack of explicit, formal concept-representation principles [16] .. The International Classification for Nursing Practice (ICNP) was launched in 1989 by the International Council of Nurses to meet the demand for a common language for nursing. The beta version of the ICNP uses combinatorial terminology for nursing practice that allows terms used in nursing practice to be cross-mapped with existing nursing vocabularies and classifications. The ICNP is a multi-axial and polyhierarchical classification of nursing phenomena, nursing actions, and nursing outcomes that facilitates expression of nursing diagnoses, interventions, and outcomes [17] .. The purpose of this article is to describe three phases in the design and evaluation of a terminology-based electronic nursing record system: (1) analysis of nursing notes including decomposition into phrases and crossmapping with the ICNP; (2) development of terminology server and electronic nursing record system; and (3) evaluation of terminology server and electronic nursing record system. This article presents methods and results of each phase following by discussion. This study was conducted to see how a concept-based terminology can be used for the computerization of narrative nursing notes and how nurses interact with the controlled terminology when performing data entry. This study began by investigating what nurses wrote in nursing notes through the content analysis of narrative nursing notes, which revealed that the decomposition of phrases well reflected the nursing process. This finding verified that mirroring the nursing process is a feasible way of structuring narrative nursing notes. Furthermore, the fact that 14,727 phrases could be expressed with only 237 unique phrases strongly demonstrates the feasibility of computerizing narrative nursing notes.. Most (156 of 257, 60.2%) nursing concepts from 237 unique nursing phrases cross-mapped with the ICNP. The mapping rate of this study was lower than that in Ryu and ParkÕs analysis of electronic nursing records for Note. C, insufficient coverage; R, inadequate representation; and U , user interface problem. Numbers in parentheses are percentage of total. internal medicine and cardiology patients at Samsung Medical Center [19] . The main reason for this difference is probably that Ryu and Park cross-mapped alreadystandardized phrases with the ICNP, whereas in the present study paper-based nursing notes without any standardization were cross-mapped with the ICNP. Most of the terms not mapped with the ICNP belonged to the focus axis of the nursing phenomena classification or the target axis of the nursing-actions classification, whereas very few unmapped terms belonged to the judgment axis of nursing-phenomena classification or action-type axis of the nursing-actions classification. This implies either that the judgment axis or action-type axis of the ICNP is well developed so that ICNP covers most of the terms used in nursing notes, or that nurses did not use diverse concepts in their nursing notes. The latter reason is more likely.. The results of this study imply that computerization of narrative nursing notes is feasible when using a concept-based nursing terminology such as the ICNP [20] . However, when computerizing nursing records, it is essential to identify specific local terminology not mapping with the ICNP to improve the expressiveness of the nursing notes.. A terminology server called the ''ICNP browser'' was developed and used to illustrate the basic principles of its combinatorial design. It was also used to add 103 new concepts, synonyms, and to create 237 precoordinated phrases for use in the user application system. The multi-axial structure of the ICNP was found to be very useful for creating precoordinated phrases.. The ICNP browser is also designed so that users can access it and it can be managed via the Internet. The server could therefore be used for the widespread dissemination of the ICNP and education of nurses about the ICNP. It could be also used in retrieving and analyzing data accumulated in clinical data servers using the concept-mapping relationship. These mechanisms facilitate the reusability of clinical nursing data and enhance their clinical study.. The evaluation method used in this study was also used in the studies of Elkin et al. [21] and Cimino et al. [22] . Their studies were carried out in the medical domain, and reported the cliniciansÕ behaviors whilst entering the patient-problem, adverse-reaction, and medication data. Their reports did not include narrative records nor perform usability tests in real clinical settings.. In system usability testing in the present study, users succeeded in entering the desired phrases in 89.4% of data-input events. The observation of nurses during documenting nursing notes using electronic nursing record system revealed that in 6% of cases the users chose an inadequate phrase because the library of precoordinated phrases lacked an appropriate phrase. This implies that the application of a terminology-based electronic nursing records system in a clinical setting requires supplementation of the precoordinated phrases.. Entering data into the system includes tree navigation, keyword searching, and re-entry function for already selected precoordinated phrases. The keyword-search function with a standard approach to coded data entry allows the user to type in a phrase and attempt to match it to a known phrase was used the most frequently. However, the tool for navigating the hierarchy of the precoordinated phrases was used only 21.3% of the total time, and re-entry function was used only 8.3% of the time. This is attributable to the users not being familiar with the tree-walking method. Many users stated they had forgotten that such functions were available, and so presumably these functions would be useful in the future.. In terms of time taken to enter data, users exhibited rapid adaptation in that the mean time required dropped from 276 to 158 s as they became more experienced. Considering that the users did not receive any formal training, other than guidance about how to use the program, such a result highlights that the use of such a program is feasible in real clinical settings.. In conclusion, this study used a systematic approach to analyze, design, implement, and evaluate a terminology-based electronic nursing records system. By evaluating the entry of coded data-from beginning to end -in actual clinical situations, we have been able to evaluate the effectiveness of the user interface and the vocabularies developed, thereby providing a basis for the iterative refinement and improvement of both. Although this study was limited to obstetric nursing, our approach could also be applied to the computerization of records in other areas of nursing. Future studies need to focus on determining how to reuse and process standardized nursing data accumulated in the clinical data server for purposes such as quality and cost management, clinical research, decision support, and healthcare policy development. The most important finding during the process of decomposing nursing notes was of patterns in the narrative nursing notes. They appeared in the following order: patientÕs complaints or nursing assessment followed by nursing problem, actions taken by nurses to solve the nursing problem, and patientÕs response to the nursing actions. Even though there were fewer phrases on nursing problems or patientÕs responses compared to other phrases, this pattern appeared repetitively throughout the nursing notes analyzed.. Decomposed phrases were divided into three groups according to their content: (i) 5907 patient-problemsrelated phrases (40.1%), (ii) 8459 nursing-actions-related phrases (57.4%), and (iii) 361 other phrases (2.5%) (see Table 1 ). When the redundant phrases (in terms of meaning) were removed, there were 98 unique patientproblems-related phrases, 114 unique nursing-actionsrelated phrases, and 25 other phrases, giving a mean of 62.1 repetitions per phrase. Twenty-five other unique phrases that could not be classified into either nursing problems or nursing actions were used to describe contextual information where nursing services were provided, an example of which is a phrase quoting a patientÕs statements or a doctorÕs care plan. When the frequencies of these unique phrases were examined, 24 patient-problems phrases appeared more than 100 times, representing 78.3% of all nursing-problems-related phrases, and 19 nursing-actions phrases appeared more than 100 times, representing 71.0% of nursing-actionsrelated phrases. There were 105 unique phrases with frequencies of less than 20 times each, representing only 6.5% of all phrases.. Decomposing the 237 unique phrases resulted in the extraction of 259 unique concepts. Among these 259 concepts, 101 concepts (39%) were related to nursing phenomena and the other 158 concepts (61%) to nursing actions. Of these concepts, 43 nursing-phenomena concepts (16.6%) and 60 nursing-actions concepts (23.2%) did not cross-map onto the ICNP (Table 2) .. A nursing phrase can provide information that is not yet included in the ICNP. For example, the phrase ''300 cm 3 of amber-colored urine is well dripping through an indwelling catheter'' is a nursing-action phrase stating that urine dripping through an indwelling catheter was observed, and this phrase was combined with axes (see Table 3 ) 2A (''observing''), 2B (''urine''), and 2C (''urine catheterization''). There is no concept to describe urine color and amount in the beta version of the ICNP, and hence we treated the information on urine color and amount as an attribute of the phrase ''urine was observed through a urinary catheter,'' where the specific values of this attribute were ''amber'' and ''300 cm 3 .'' 3. Phase 2: development of terminology server and electronic nursing record system. Fig . 1 shows the core elements of the electronic nursing record system. The user application system, which forms part of the clinical information system, communicates with the clinical data server to obtain patient demographic data and to upload nursing records. Staff nurses access the clinical information system via workstations (usually IBM-compatible PCs using client module software). The ICNP terminology-server administrator accesses the terminology server through an Internet browser.. A total of 2737 concepts including existing ICNP concepts and 103 new concepts found during the analysis of nursing notes, and 237 precoordinated phrases are managed with the ICNP terminology server (see Fig. 2 ). Users document with precoordinated phrases in the electronic nursing record system. Fig. 2 shows the logical cycle of the presenting process of the precoordinated phrases and representing process of finding new phrases. The users documented nursing notes using the precoordinated phrases, and the terminology administrator in turn managed precoordinated phrases through the representing process of new phrases.. A version of the ICNP terminology server that runs on the Windows 2000 Server operating system is available on the Web. Users can locate an ICNP concept by hierarchical navigation or keyword searching. The ICNP hierarchy is displayed graphically to make it easy for users to understand its structure. The Fig. 3 shows a navigation result when using the ICNP view function. Once the browser locates a nursing concept, it displays the English concept label, ICNP code, and definition of the concept. The terminology browser is designed to allow users to create a library of precoordinated phrases using the ICNP axes, and to define links among the concepts. For example, let us assume that we want to create the following precoordinated phrase: ''there is edema in the left lower extremity.'' The user could search for ''edema'' from the focus axis of the phenomena classification, and add this to a nursing phrase (see Fig. 4) . The user could then search for the concept ''yes'' from the judgment axis, and add this to the nursing phrase. Finally, the user could search for the concept ''left lower extremity'' from the body-site axis, and add this to the nursing phrase. The user can reorder the concepts added to the nursing phrase to improve the way that it is expressed. If the precoordinated phrase matches any phrase from an existing nursing terminology or classification system, the browser displays its corresponding code. The user application system was developed to support documenting narrative nursing notes using a controlled library of precoordinated phrases. The user interface consists of two main modes of data display and input. The display shows the selected patientÕs nursing notes from the admission date through to three views of a summary table of the patientÕs problems (nursing assessment and evaluation), a summary table of nursing actions, and narrative nursing notes composed of the selected precoordinated phrases (see Fig. 5 ). In the input mode, the users can select a precoordinated phrase or combinations of phrases by navigation and search functions (see Fig. 6 ). Users can add detailed information to a phrase by inputting attributes or free text. For easier data input, precoordinated phrases are displayed in a hierarchy of categories. A re-entry function for already selected precoordinated phrases is also available (see Fig. 6 ). . The characteristics of the participants are listed in Table 3 . Most (65%) of the subjects were 30-39 years old, and 80% of the subjects were qualified to at least baccalaureate level. The mean working experience in nursing was 113.3 months (SD 45.2 months), with the mean working experience in maternity nursing being 61.6 months (SD 40.7 months) ( Table 3) .. Analysis of the videotape of nursesÕ interactions with the electronic nursing record system, 20 nurses documented the nursing notes of 57 patients 158 sessions with 1126 phrases (see Table 4 ). On average, each nursing-note-documenting session consisted of 5.6 phrases (SD 2.6 phrases). Out of 1126 phrases, 394 (35.0%) precoordinated phrases were used to describe patient problems, 31 (2.8%) precoordinated phrases described nursing diagnoses, and 455 (40.4%) precoordinated phrases described nursing actions. Three hundred and ninety-seven phrases were described in more detail, with 481 attribute values. Nurses added 246 freetext phrases, in situation where they could not find an appropriate phrase from the library of precoordinated phrases. Most of these free-text phrases described contextual information, such as quoting a patientÕs words or a doctorÕs care plan. Nurses used keyword searching more than other input methods when they needed to locate an appropriate precoordinated phrase; an average 1.35 keywords were used in this searching process. The time required to find and input a precoordinated phrase ranged from 2 to 159 s, with a mean of ''23.93'' s. Table 5 shows the data relating to whether or not a desired precoordinated phrase was found successfully. Users were able to find 787 out of 880 (89.4%) precoordinated phrases successfully. Out of 93 suboptimal or failed phrase selections, 84 phrases (47 phrases for patient problems and 37 phrases for nursing actions) were not matched with what they intended to describe. Nurses failed to find nine desired precoordinated phrases (five phrases for patient problems and four phrases for nursing actions). Out of 93 suboptimal or failed phrase selections, 35 phrases were not available in the library of the precoordinated phrases. Users failed to find 40 of the desired phrases even though they were in the library: this was due to nurses choosing an incorrect phrase or entering free-text phrases. The most frequent reason for failure was that the precoordinated phrases did not have synonym or abbreviation that users were looking for (such as ''shaving'' for ''skin preparation''). There were 18 failed phrases due to interface problems.. The time required to document nursing notes was analyzed. Fig. 7 compares the input time with the selection of precoordinated phrases, free text and total input. The figure shows that the total mean input time required for each nursing-notes-documenting session decreased significantly from 276 to 158 s as the users became more experienced. The development of an electronic nursing records system requires an understanding of the content of narrative nursing notes in current nursing practice. Here the nursing notes of patients who were discharged from the obstetric units of a Korean tertiary teaching hospital prior to March 2000 were analyzed. The narrative nursing notes were decomposed into phrases and coded by meaning. Each phrase in turn was decomposed into concepts and cross-mapped with the ICNP. Patients were divided into five categories: (i) normal delivery, (ii) scheduled caesarian section, (iii) normal delivery with complications, (iv) antepartum problems, and (v) postpartum problems. Analysis of nursing notes was stopped when no more new phrases were found-for each subject category this occurred when the nursing notes of around 15 patients had been analyzed. In total, the nursing notes of 63 patients were analyzed.. A Web-based ICNP terminology server was developed, the functions of which were ICNP navigation, concept management, and precoordinated-phrase management. The ICNP navigation function allows the users to explore the structure and content of the ICNP. The concept-management function is used to extend the original ICNP by adding a new concept, or updating or deleting a concept added to the original ICNP. Precoordinated-phrase management allows the users to create, update, or delete a library of precoordinated phrases for nursing problems, signs and symptoms, diagnoses, goals, interventions, and evaluations. Each precoordinated phrase can have attributes for detailed expression. For the development of the user application system, phrases of narrative nursing notes were structured according to the nursing process. The design of this system took into consideration the cyclical process of ongoing nursing assessment, intervention, and evaluation.. The relationship between the terminology server and the user application system was identified and designed as a logical system model. From the system analysis and design, a Web-based ICNP terminology server and client/server based user application system were developed and implemented on the Microsoft Windows platform. The Korean version of the beta version of the ICNP, which was translated by the Nursing Informatics Research team [18] , was used for the ICNP terminology server. The terminology server and user application system shared the same database, and thus the precoordinated phrases created by the ICNP terminology server were used in the user application system.. When evaluating the terminology-based electronic nursing record system, we tested the performance of the terminology server and the user application system at the same time. Two tertiary teaching hospitals that have hospital information systems were selected as test beds. Twenty volunteer nurses with a minimum experience of 1 year in obstetric nursing care were recruited. All participants agreed to think aloud and be videotaped while they used the user application system to document the nursing notes of three patients per day during their six duty days. The videotape was transcribed and annotated to reflect how nurses behaved whilst documenting nursing notes.. We categorized the process of data entry into three groups based on the success in finding a desired precoordinated phrase: (i) if the user was able to select a precoordinated phrase that matched exactly what the user wanted to document, this was categorized as a ''success;'' (ii) if the user could not find a desired precoordinated phrase and consequently did not enter the data, this was categorized as a ''failure;'' and (iii) if the user selected a precoordinated phrase which did not match what the user wanted to document, this was categorized as ''suboptimal.'' The failure and suboptimal categories were further categorized into ''insufficient coverage'' (where there was no appropriate precoordinated phrase in the library), ''inadequate representation'' (where the user could not locate the desired precoordinated phrase-even though it was in the library-due to a missing synonym or unrecognized abbreviation), and ''usability problems'' (userinterface problem). We measured the time required to document the nursing notes.

O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O 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Distinguishing Views in Symmetric Networks: A Tight Lower Bound The view of a node in a port-labeled network is an infinite tree encoding all walks in the network originating from this node. We prove that for any integers n ≥ D ≥ 1, there exists a port-labeled network with at most n nodes and diameter at most D which contains a pair of nodes whose (infinite) views are different, but whose views truncated to depth Ω(D log(n/D)) are identical. The notion of a view was introduced and first studied by Yamashita and Kameda in [19] in the context of distributed message passing algorithms. In so-called anonymous networks (without unique identifiers accessible to a distributed algorithm), the view is a fundamental concept which allows for identification of the network topology and for breaking of symmetries between nodes. Different views for a pair of nodes guarantee that the corresponding nodes are distinguishable, which is useful in, e.g., leader election algorithms. View-based approaches have been successfully used when designing algorithms for various network problems, including map construction [3, 9] , leader election [4, 6, 8, 12, 17, 20] , rendezvous [5, 7, 13] , and other tasks [10, 18] .. The view from a node of a network is by definition (cf. Section 2) an infinite rooted tree, and therefore distributed algorithms (both for agents exploring the network or for the nodes in message passing models) can only know a finite subtree of the view. This motivates the question about the minimum integer l such that the view truncated to dept l contains all crucial information an algorithm may need.. Yamashita and Kameda proved that if views of two nodes truncated to depth n 2 are identical, then their infinite views are identical [19] , where n is the number of nodes of the network. The bound has been improved to n − 1 by Norris [15] . Although this bound is asymptotically tight [1, 15] , it is far from being accurate for many networks. Hence, one may ask for bounds expressed as function of different graph invariants. Fraigniaud and Pelc proved in [11] that if two nodes have the same views do depth n−1 then their views are the same, where n is the number of nodes having different views (or equivalently, n is the size of the quotient graph [19] ). For some works on view computation see, e.g., [2, 16] . Recently, Hendrickx [14] proved an upper bound of O(D log(n/D)) on the depth to which views need to be checked in order to be distinguished, where D is the diameter of the network, leaving the tightness of this bound as an open problem.. In this work we provide a corresponding lower bound of Ω(D log(n/D)). In particular, for each D ≥ 1 and n ≥ 1 such that n ≥ D · 2 12 /3, we construct an n -node graph G with diameter D such that taking truncations of the view to depth 1 6 D log 2 (n /D ) − 0.41D does not guarantee distinguishing a pair of nodes of this graph, which do in fact have different (infinite) views. Our construction is done in two steps. First, a list of graphs G l , l ≥ 1, is defined with the following properties: (a) diam(G l ) = 3 for each l ≥ 1, and (b) G l contains two nodes a l and b l such that the views from them to depth l = Θ(log n) are identical but their (infinite) views are different, where n is the size of G l . Next, in order to extend the bound for arbitrarily large diameter D we then modify G l by subdividing each of its edges roughly D /3 times so that the new graph: (a) has diameter roughly D , and (b) contains two nodes a l and b l such that their views are the same till depth Θ(D log 2 (n /D )) but their views are different, where n is the size of the subdivided graph.

O O O O O O O O O O B O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B I O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O B O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O