Database system in the KEK LINAC PC-based control(1. Operation Logging and Statistical Processing System)

Masahiko Tanaka, Mitsubishi Electric Co., Ltd. Tsukuba
Isamu Abe and Hitoshi Kobayashi, KEK, Tsukuba, Japan

Abstract
In the KEK e+/p- (electronic positron) Linac (linearaccelerator), 2.5GeV was boosted to 8.0GeV, and its
database was reinforced, particularly that for recording
operational use and statistical processing. An outline ofthe system and its results are presented.

1 INTRODUCTION
A database (DB) [1] was made for KEK’s 2.5GeV e+/plinear accelerator, and has been used since 1994. In 1998
the accelerator was upgraded to 8GeV, with the DB
system being expanded.
More than one might imagine, considering therequired effort, to include tuning and maintenance,
making a DB is not easy for an accelerator and examples
of prominent success are indeed rare, conspicuously so in
OODB.
However, recent progress in personal computer (PC)development has led to simplified, inexpensive PC DB
systems being readily adaptable to the accelerator field,
thus allowing greater flexibility, and practical-use
statistical processing, etc.
Systems so far designed for 2.5GeV accelerators
remain largely unchanged. Figure 1 shows a system
diagram.
AccessDevelopment stations

Operator’s console
NT4.0

Windows NT

need for computerisation was discussed, and following theintroduction of an NT server, it saw practical use in theMS-SQL and PC system. The accelerator’s dynamic DB
also records (1) beam operation, (2) accelerator operationand (3) trouble and troubleshooting, although they do not
require a real-time response, compared with otherdynamic DB.
In beam operation auto recording, matters related toits on/off operation and radiation safety as well as safety
interlock systems are simultaneously logged in the DB,
and a MS-Word file is also created daily, the DTP
function can be used by selecting the appropriate file on
any network PCs.

Fig.2 Layout of papers for publication at PCaPAC’99.
NT4.0

NT4.0

NT4.0

3 PRIOR TO APPLICATION
Human I/F layer
G/W (COACK)NT server

NT4.0
Operator’s
consoleMS-SQL
database

Pentium 200MHz
4CPU multi
128MB, 19GB
Windows
NT4.0server

Device layer

Fig.1 Database and the PC system

2 OPERATIONAL DATABASE ANALYSIS
After the PF incidentor began operation of an electronicpositron linear accelerator, operational and trouble
recording was hand-written, resulting in a huge volume ofdata that was already hard to reuse, with the records left togather dust. Since past statistics require processing, theThe following data structure analysis, a four-step process,was needed to make and apply the operational and trouble
logging DB:(1) Operational and trouble data-base analysis(2) DB design and GUI design(3) DB system verification of temporary data
(4) Operator training and transition periods(5) Actual operation(6) Performance evaluation(7) Version upgrade

4 GUI AND DBBased on an analysis of the DB needed for the MS-SQL 5,
matters were decided, with the DB being made as a result.
Since the GUI required better software development,
several systems were studied; but considering the problem
of compatibility with Windows, Access was chosen whichenables simultaneous reduction of the SQL’s CPU load.
Shown below are input screens for operational and trouble
recording.

VDT syndrome. Some operators mentioned that problems
might occur, but effort went into mitigating their concern.

7 STATUS OF ACTUAL OPERATIONThe SQL DB was constructed by MS-SQL Enterprise-M,
withmaintenanceeffectedbyMS-ISQL/W.
Mmaintenance GUI windows were made by VB, enabling
the operator to conduct all input and necessary searches
via the GUI. In addition, the search function weny torelated personnel other than operators via the web (Fig. 4).

Fig.4 Example of a Keyword Search by the Web
Fig.3
Operational/trouble Recording Input GUI Examples

5 DEBUGGING BY TEMPORARY DATA
By the time the system was completed, about threemonths worth of hand-written data had been input; also,operational performance, usability and speed tests hadbeen completed, with its practicality verified. A variety ofproblems linked with transition to actual use wereconsidered. Accordingly, a preparation period wasprovided instead of attempting the transition all at once.

6 OPERATOR TRAINING AND
TRANSITION PERIOD
Accelerator operation is contracted to a third-sectorcompany. With Japanese keyboard, since the load wasgreater than usual for operators unaccustomed tocomputers, a transition period was allowed. In as much asinputting Japanese for operational recording is harder thanhand-writing, the issue of input speed was studied. The
problem was treated in three stages, from hand-writing to
combined hand-writing and computer input (1997 to May‘98), then to computer input alone (May ‘98 andthereafter).
Prior to a shift to computerisation, a poll was taken
among operators to determine how the transition would
affect them, matters like the psychological burden and the8 ANALYTICAL/STATISTICALPROCESSING BY DB
Volume wise, accelerator operators input about 60MB ofdata regarding Linac operation from 1995 to 1998,
including the test period; about 8MB were input in thetrouble file during the same period. The following are
examples of analytical and statistical processing ofcomplications drawn from the trouble-recording database.
(1) Search by keywords related to shutdowns, etc. showedthat 64% of all troubles stemmed from stoppage owing to
one factor or another, 17% of the problems were of
unknown origin. In nearly all cases normal resetting
activated the accelerator Keyword search by device
module names when itemising the origin of trouble
revealed a trend where 18% of the problems involved
power supply and a module of the same type.
(Trouble-related Statistical/analytical Processing)From the aspect of keyword question frequency, it waslearned that problems occurred in the order of power
supply, unknown-origin troubles and communication
faults.
(2) In analysing periodic troubles, an increase in thefrequency during specific months described a trend overthe past several years (Fig.5), it was learned that troubles
often occur in the wake of the semi-annual maintenance.

tabulations concerning
maintenance.

accelerator

operationand(2) Although there were at first differences in entering thenames of equipment and other factors, depending on therecorder, an analysis of actual past cases showed that thedescription content has been standardised as a result of thecapacity to create and select keyword items from the popup menu, and statistical processing has become easier toperform and to understand.

SepO
ct
Nov
Decl
Aug

JuFeb
M
ar
A
prM
ayJu
n

160
140
120
100
80
60
40
200Janevents

Trouble rate per monthmonth

Figure 5 Trouble Frequency by Month

911 FUTURE SUBJECTS

System Evaluation by Operators(1) In operational recording, formerly hand-written
storage-use and storage-use copy files had been prepared,
the use of the DB has greatly lightened this drudgery.
(2) Substantial revisions of hand-written records caused atremendous burden on operators. GUI tools enable doing
the job far more smoothly.
(3) Previously, trouble recording, etc., had been recordedby hand, requiring extensive time; however the DB madethe task possible within a remarkably short time (Fig. 6).

Based on evaluations of the DB system and its practicaluse to date, the following are expected to be tackled as
future subjects:•••(1) Complete keyword definitions to enable
expanded reuse, an increase of items, and lighter
keyboard input load.
(2) Create more screens to boost keyword
flexibility and reinforce the macros for each type oftabulation.
(3) Intensify the web-link density and increase thescreens according to the general trend.

814%

4%

Fault shutdown
50%

6%

RF system trouble26%

 syste system

56%

3% 2%

MBSBKLY
SHB

Vacuum system
Control system
Gun system

39%

Figure 6 Statistical Processing Display Screen(4) When investigating keyword search frequencies andtrends, registering and inputting the results as keywords
enables easy selection from the pop-up menu, which
greatly lightens the keyboard input load.
(5) The new system makes it possible to retrieve examples
corresponding to troubles with the GUI Access search
program and visually display data that reflect accelerator
operation, which is very convenient.

10 DATABASE OPERATION SUCCESSSTORY(1) DB total search capability enables trouble
categorisation, which simplifies reflecting the results ofSUMMARY

The accelerator operational DB based on Windows NT,
MS-SQL and MS-Access has proved itself satisfactory asa PC system. The foregoing describes the worth of theDB from the aspect of accelerator operation and trouble
analysis. The processing speed fully responds to thenecessary conditions. Consequently, it is foreseen thataccelerator operation will become even easier in thefuture by effective application, and that highly detailed
operations will be possible.
•REFERENCES[1] M.Tanaka, I.Abe and Others,“Database system for Linac operation support”
Linac conference ’97, Sendai, Japan[2] I.Abe and M.Tanaka" Feedback of operators’ experiences to console programs inthe KEK e-/e+ Linac"
ICALEPCS97, 1997 Beijing, China