bluuebunny/crossref_metadata_2025 huggingface dataset:
The perceived effectiveness of audit committees in the South African public service
Authors: van der Nest D.P.
Published: August 2011

Audit committees have increasingly been recognised as an integral part of modern control structures and governance practices in both the private sector and public service. The audit committee is an integral element of public accountability and governance processes. It plays a key role in underwriting the integrity of corporate governance of a government department. The broad aim of this study is to investigate the status and function of audit committees in South African national government departments. The research question investigated in this paper is to determine whether audit committees in the public service are perceived to be effective in assisting accounting officers of government departments to discharge their responsibilities. The study concludes that the majority of audit committees in the South African public service are not perceived as ineffective in the performance of the required functions of committees. Audit committees can still improve their effectiveness in their performance of certain key functions in the areas of oversight over risk management, governance, financial reporting, internal control and support for the external audit function.
Performance management in the South African motor manufacturing industry: a framework
Authors: van der Merwe N. , Visser S.S.
Published: August 2011

South African motor manufacturers should find ways to improve their performance management systems to ensure survival in the face of strong competition in the market. The main objective of this study is to evaluate the industry’s approach to performance management and to make recommendations about a framework for performance management that can be implemented to obtain a competitive advantage. A well‐known instrument that proves to be highly effective in performance management is the balanced scorecard. This instrument manages performance on four distinct levels, namely from the financial perspective, the customer perspective, internal business processes and learning and growth. It is apparent from the results of this study that performance management is still very much a one‐way process, and that a lack of communication is the primary reason for unsatisfactory workforce performance. Furthermore, the majority of motor manufacturers consider the customer perspective as the most important of the four above‐mentioned perspectives. Motor manufacturers also disagree about the number of performance measures that need to be included in the performance management system, and the majority feel that both controllable and non‐controllable fixed costs must be included in the measurement of management performance. Shareholder value measures are also largely neglected in practice.
Do our children know anything about money? An exploratory study
Authors: de Clercq B.
Published: August 2011

South Africans, like many people worldwide, need to save more and spend less. The question arises why people do not save enough for their retirement and other financial needs. In this exploratory study, age, gender and the amount of pocket money that learners receive were evaluated to determine their impact on the level of learners’ financial literacy. The author concluded that of the three variables evaluated, only age has a significant effect on the level of learners’ financial literacy.
Tax topics a trainee chartered accountant should be taught: a survey of perceptions in and outside public practice
Authors: Joubert B. , Coetzee S. , Oberholzer R.
Published: August 2011

This paper presents the results of a survey designed to determine what tax topics are important in the educational background of a trainee accountant entering the training environment in South Africa. These topics were then compared to the 2008 tax syllabus prescribed by SAICA and taught at accredited universities in respect of the 2009 Qualifying Examination. The results indicated that the 2008 syllabus is largely meeting the expectations of respondents both in and outside public practice, although there are a number of topics that the syllabus setters and educators should reconsider when next reviewing and updating the 2008 syllabus and as part of the considerations for the new competency framework.
Working in teams: improving the team experience
Authors: Stainbank L.J.
Published: August 2011

IES 3 Professional Skills, issued by the International Federation of Accountants in 2003, lists five essential skills that professional accountants need to acquire: intellectual, technical and functional, personal, interpersonal and communication, and organisational and business management skills. In education programmes, accounting students may be required to work in teams and may therefore acquire some of these skills through the team experience. IES 8, Competence requirements for audit professionals, includes “working in teams effectively” and “presenting, discussing, and defending views effectively through formal, informal, written, and spoken communication” as part of the skills requirement which should be included in the education and development programme for audit professionals. Working in teams, or cooperative learning, is a teaching technique used in the formal education phase, which enables students to acquire some of these skills. The paper uses the results of a questionnaire survey to investigate how teams function in an accounting project. Although the results indicate that skills such as meeting management and interpersonal skills have a positive effect on the students’ satisfaction with the team, no link could be found to the students’ project mark. These results suggest that skills such as meeting management and interpersonal skills, if included in the formal education phase, may contribute positively to students’ career preparedness. The study also found that students did not consider peer assessment appropriate.
IFRS for SMEs in South Africa: a giant leap for accounting, but too big for smaller entities in general
Authors: van Wyk H.A. , Rossouw J.
Published: August 2011

According to generally accepted accounting practice, the objective of financial statements is to provide useful information to the primary user groups of such statements, regardless of the size of the entity. The primary users of the financial statements of SMEs are the owners, South African Revenue Services (SARS) and bankers. The recognition, measurement and disclosure requirements of full IFRSs do not result in cost‐effective and useful information being provided to the users of the financial statements of SMEs (non‐listed companies, close corporations and other small entities, irrespective of their legal form), because these users do not need the extensive and complex information provided in general purpose financial statements. Consequently, an accounting standard is required to differentiate between general and limited purpose financial statements. The International Accounting Standards Board (IASB) issued an exposure draft (ED 222) on IFRS for SMEs in February 2007. These stipulated modifications relating mainly to relaxed disclosure requirements and are more applicable to medium‐sized entities. According to a survey among preparers of financial statements in June 2007, these developments may not be adequate for the purposes of smaller entities, irrespective of their legal form. Accordingly, the study recommends that a formal, separate set of simplified differential reporting standards be developed for smaller entities.
An investigation into students’ perceptions of accountants
Authors: Wessels P.L. , Steenkamp L.P.
Published: August 2011

Prior accounting education literature documents that stereotypical images abound of the accountant as introverted, systematic, antisocial and boring. Although these stereotypes clash with the skills required of modern professional accountants to be problem solvers who regularly interact with people, the question is whether students wishing to become accountants still have these stereotyped perceptions. The purpose of this article is to investigate the preconceived notions of students in South Africa about accountants and whether these perceptions differ because of gender, home language or ethnical differences. A comparison is also made of the perceptions of school‐leavers and final‐year students to determine whether these perceptions change during students’ formal period of study at universities. This research, which is currently highly relevant, given the shortage of students pursuing careers as accountants, could contribute to the debate surrounding the concerns of the future of the accounting profession and the implications for contemporary accounting education. It was found that students perceive accountants as structured, precise and solitary individuals. However, students considered it to be an interesting profession. Significant differences were found between the perceptions of different ethnic groups. No significant differences were found between the perceptions of male and female students, or between Afrikaans‐ and English‐speaking students.
The application and constitutionality of the so called “reverse” onus of proof provisions and presumptions in the Income Tax Act: the revenue’s unfair advantage
Authors: Goldswain G.K.
Published: August 2011

This study analyses and discusses the application and constitutionality of the general onus of proof provision (section 82 of the Income Tax Act 58 of 1962 [the “Act”]), the presumption in favour of the State when criminal sanctions are applied to an offending taxpayer (section 104(2) of the Act) and the mechanics for imposing administrative sanctions in terms of section 76(1)(b) of the Act. The conclusion reached is that the reverse onus presumption, as provided for in terms of section 104(2) of the Act, is unconstitutional. It is penal in nature and offends against the constitutional right of an accused to a fair trial (sections 35(3) of the Constitution of the Republic of South Africa Act, 108 of 1996 [the “Constitution”]). The section 36 limitation of rights clause of the Constitution does not save it. Section 76(1)(b) of the Act read in conjunction with the deeming provision of section 76(5) of the Act, is inextricably linked to the section 82 general reverse onus provision of the Act. Hence, when these three sections are applied together, they create a reverse onus that, prima facie, violates the right to just administrative action (section 33 of the Constitution). Regarding the general reverse onus burden as provided for in terms of section 82 of the Act, the conclusion reached is that it is reasonable and justifiable in an open and democratic society and can therefore be regarded as constitutional.
Comparing levels of career indecision among selected honours degree students at the University of Pretoria
Authors: Jordaan Y. , Smithard C. , Burger E.
Published: August 2011

Career indecision plays a major role in the way students perceive their future career prospects and how they approach these prospects. In addition, career indecision influences career‐related thoughts and decisions, and plays a role in the way students formulate career goals. A convenience sample from honours students in Accounting Sciences, Financial Management, Economics and Marketing was drawn and their levels of career indecision were measured using self‐administered questionnaires. The study demonstrates that differences exist between students whose employment status differs, and those who were studying for different degrees. Consequently, this study has vital implications for groups (such as career counsellors and educational institutions) involved in the career decision‐making processes of university students.
Methods of choice in the valuation of ordinary shareholders’ equity: evidence from theory and practice
Authors: Nel W.S.
Published: August 2011

The question that inevitably surfaces in practice, and certainly in lecture halls, is which equity valuation method is superior. Popular opinion holds that academia and investment practitioners may have different preferences in this regard. This article investigates which primary minority and majority equity valuation methods are advocated by academia, and how well these preferences are aligned with the equity valuation methods that investment practitioners apply in practice. The research results reveal that, contrary to popular belief, academia and practice are fairly well aligned in terms of preferred equity valuation methods, with notable differences in their respective approaches.
The value added statement: does it add any value?
Authors: Stainbank L.J.
Published: August 2011

The value added statement has been voluntarily reported by South African companies for many years despite reservations about its usefulness. This article examines current literature on value added statements in two areas: the usefulness of the value added statement in South Africa and the relevance of social accounting theories in explaining its continued disclosure in South African listed companies’ annual reports. It also reports the results of a questionnaire survey addressed to preparers of value added statements.The research studies examined in the literature review indicate that legitimacy theory is more likely to provide an explanation for the disclosure of value added statements in annual reports in South Africa. The results of the empirical survey indicate that the majority of the respondents are of the opinion that it is desirable to prepare a value added statement, but that it is not used in the majority of companies. Furthermore, the reasons advanced by the preparers for the desirability of the value added statement provide some evidence that legitimacy theory may be behind the propensity of companies to publish a value added statement. The article recommends that the preparation of the value added statement should be standardised. However, the disclosure of an independently prepared value added report may be more useful to all users.
The role of accounting theory in the development of accounting principles
Authors: Coetsee D.
Published: August 2011

Accounting theorists agree that no comprehensive theory of accounting has yet been developed. In the absence of such a theory, the question arises whether sufficient accounting principles are created through accounting research. This article acknowledges that accounting principles are not solely the result of academic research and that current accounting practice through its standard‐setting process contributes far more to the development of accounting principles. Hence the role that accounting theory and research should play in developing accounting principles is a vital academic question. The discussion in the article focuses on the normative and descriptive (or the more modern positivistic) approach to the development of accounting theory, the positivistic nature of mainstream accounting research, a possible decision‐useful theory of accounting and the role of interpretative and critical research. All of these developments are beneficial to accounting since they open up accounting to a diversity of research approaches that will collectively improve the status of accounting research and possibly accounting theory. The role that these developments fulfil in creating appropriate accounting principles, however, is debatable.
Audit committee responsibilities vis‐á‐vis internal audit: how well do Top 40 FTSE/JSElisted companies shape up?
Authors: Marx B. , Voogt T.
Published: August 2011

Effectively functioning audit committees have proven to fulfil a vital role in strengthening the role of internal audit. This article presents the results of a literature review that pinpoints six responsibilities that audit committees should perform in relation to internal audit. These responsibilities were tested as part of an empirical study focusing on the 40 largest companies listed on the JSE to determine the extent to which large listed companies in South Africa fulfil and disclose these responsibilities. The study consisted of an analysis of annual reports and a questionnaire administered to the chairs of audit committees. The study returned significant findings, including sound empirical evidence that the audit committees of the largest listed companies in South Africa are executing their responsibilities for internal audit effectively, but are performing more functions and responsibilities than those actually disclosed and reported on. While this apparent deficiency in disclosure may not affect the effective functioning of audit committees, it may influence perceptions about this effectiveness.
Effective integration of SMS communication into a distance education accounting module
Authors: van Rooyen A.A.
Published: August 2011

The University of South Africa (Unisa), as a distance education institution, is continuously challenged to lessen the negative impact distance has on students’ learning. The effective use of technologies affords distance education institutions with valuable opportunities to enhance teaching and support students’ learning. Using online technologies in the context of a developing country like South Africa often remains unrealised because of the persistent impact of lack of access, bandwidth and cost to students. Most students, however, have mobile phones, thus creating an ideal opportunity for distance education institutions to increase the effectiveness of learning. This article investigated students’ responses to a pilot study aimed at integrating short message systems (SMSs) into the study experience of accounting students at Unisa. This research found that students overwhelmingly experienced this initiative not only as support but also more importantly as assistance to enable them to study more effectively. On the basis of the evidence provided, it is evident that using mobile technology can enhance the learning experience of accounting students and provide them with a more satisfying and successful experience.
Tax incentives for biodiversity conservation in the Western Cape
Authors: van Wyk E.
Published: August 2011

Biodiversity conservation tax incentives were inserted into the Income Tax Act 58 of 1962 in terms of the Revenue Laws Amendment Act 60 of 2008 and are now contained in section 37C. The objectives of this study were to quantify the maximum potential revenue loss, to National Treasury, as a result of these tax incentives granted to landowners in the Western Cape; to identify and discuss alternative policy instruments to encourage conservation; and to investigate the perceptions of landowners in the Western Cape on the tax and alternative incentives available for conservation. The study found that the maximum tax revenue foregone should amount to a tiny percentage of total estimated revenue income for the 2008/2009 fiscal year, while projected future losses could also be insignificant. Landowners prefer direct financial incentives and exemption from property taxes, and contend that direct assistance with conservation activities would also be beneficial. The use of municipal value in the valuation of land would promote objectiveness and consistency. Finally, only a third of the landowners indicated that tax incentives would encourage them to commit more land for conservation.
An exploratory study of the focus areas of South African Top 40 company CFOs
Authors: Voogt T.
Published: August 2011

The roles and responsibilities of the chief financial officer (hereafter CFO) have evolved dramatically over the past 10 years. This article explores this evolution from a South African perspective by, firstly, presenting an extensive literature review on the matter. Secondly, a unique South African model of the key focus areas for CFOs is proposed. Lastly, the results of a questionnaire administered to the CFOs of FTSE/JSE Top 40 companies are reported. The results revealed significant findings relating to the CFO’s most important current and future role ‐ that of planner and strategist. In addition, CFOs at the top of the corporate ladder expect to focus more on their role as a growth and innovation catalyst. This article also identifies three key areas for future research that will make an important contribution to the continued development of the educational framework for chartered accountants.
The incorporation of soft skills into accounting curricula: preparing accounting graduates for their unpredictable futures
Authors: de Villiers R.
Published: August 2011

This paper explores the changing needs of employers and the business community in relation to the balance between technical and soft skills, such as communication skills, business presentation skills and other interpersonal skills. The researcher discusses the importance of soft relational skills for all business graduates, including accountants. The study further explains how soft skills can complement the technical skills taught to ensure that graduates are equipped to deal with the demands of a complex global business environment. The needs of different stakeholders, possible barriers to change and the way in which academic faculty can contribute are reviewed.
Applying the Canadian “reasonable expectation of profit” test to a section 80M(1)(d) reportable arrangement
Authors: Steenkamp L‐A.
Published: August 2011

A section 80M(1)(d) reportable arrangement is defined in the Income Tax Act 58 of 1962, as amended, and contains the reasonable expectation of a pre‐tax profit requirement. Such an arrangement must be reported to the Commissioner of the South African Revenue Service within 60 days. Failure to do so can result in a R1 million penalty. It is submitted that this requirement is subjective because of a lack of indigenous litigation and implementation guidelines. The Canadian reasonable expectation of profit (REOP) test may be of value to formulate objective standards against which to apply the section 80M(1)(d) reportable arrangement.
The impact of the Minerals and Petroleum Resources Royalty Act on the South African mining industry: a critical analysis
Authors: van der Zwan P. , Nel P.
Published: August 2011

The Minerals and Petroleum Resources Royalty Act (MPRRA) became effective on 1 March 2010. This legislation may have a significant impact on employment, foreign investment and future exploration in the South African mining industry. This article reports on a critical analysis of the MPRRA prior to its implementation in order to identify aspects that may impact adversely on the South African mining industry and would require further research after the implementation of the MPRRA. Based on the findings, the authors recommend that the impact of the level of royalties levied as well as the mechanism to promote downstream beneficiation be researched to establish whether the legislators ought to reconsider these provisions in the light of their impact on the mining industry.
The investigation of the influence of laser re‐melting on density, surface quality and microstructure of selective laser melting parts
Authors: Yasa Evren , Deckers Jan , Kruth Jean‐Pierre
Published: August 2011

Purpose

Selective laser melting (SLM) is a powder metallurgical (PM) additive manufacturing process whereby a three‐dimensional part is built in a layer‐wise manner. During the process, a high intensity laser beam selectively scans a powder bed according to the computer‐aided design data of the part to be produced and the powder metal particles are completely molten. The process is capable of producing near full density (∼98‐99 per cent relative density) and functional metallic parts with a high geometrical freedom. However, insufficient surface quality of produced parts is one of the important limitations of the process. The purpose of this study is to apply laser re‐melting using a continuous wave laser during SLM production of 316L stainless steel and Ti6Al4V parts to overcome this limitation.

Design/methodology/approach

After each layer is fully molten, the same slice data are used to re‐expose the layer for laser re‐melting. In this manner, laser re‐melting does not only improve the surface quality on the top surfaces, but also has the potential to change the microstructure and to improve the obtained density. The influence of laser re‐melting on the surface quality, density and microstructure is studied varying the operating parameters for re‐melting such as scan speed, laser power and scan spacing.

Findings

It is concluded that laser re‐melting is a promising method to enhance the density and surface quality of SLM parts at a cost of longer production times. Laser re‐melting improves the density to almost 100 per cent whereas 90 per cent enhancement is achieved in the surface quality of SLM parts after laser re‐melting. The microhardness is improved in the laser re‐molten zone if sufficiently high‐energy densities are provided, probably due to a fine‐cell size encountered in the microstructure.

Originality/value

There has been extensive research in the field of laser surface modification techniques, e.g. laser polishing, laser hardening and laser surface melting, applied to bulk materials produced by conventional manufacturing processes. However, those studies only relate to laser enhancement of surface or sub‐surface properties of parts produced using bulk material. They do not aim at enhancement of core material properties, nor surface enhancement of (rough) surfaces produced in a PM way by SLM. This study is carried out to cover the gap and analyze the advantages of laser re‐melting in the field of additive manufacturing.
Transient thermal response in ultrasonic additive manufacturing of aluminum 3003
Authors: Schick David , Suresh Babu Sudarsanam , Foster Daniel R. , Dapino Marcelo , Short Matt , Lippold John C.
Published: August 2011

Purpose

Ultrasonic additive manufacturing (UAM) is a rapid prototyping process through which multiple thin layers of material are sequentially ultrasonically welded together to form a finished part. While previous research into the peak temperatures experienced during UAM have been documented, a thorough examination of the heating and cooling curves has not been conducted to date.

Design/methodology/approach

For this study, UAM weldments made from aluminum 3003‐H18 tapes with embedded Type‐K thermocouples were examined. Finite element modeling was used to compare the theoretical thermal diffusion rates during heating to the observed heating patterns. A model was used to calculate the effective thermal diffusivity of the UAM build on cooling based on the observed cooling curves and curve fitting analysis.

Findings

Embedded thermocouple data revealed simultaneous temperature increases throughout all interfaces of the UAM build directly beneath the sonotrode. Modeling of the heating curves revealed a delay of at least 0.5 seconds should have existed if heating of lower interfaces was a result of thermal diffusion alone. As this is not the case, it was concluded that ultrasonic energy is absorbed and converted to heat at every interface beneath the sonotrode. The calculated thermal diffusivity of the build on cooling was less than 1 percent of the reported values of bulk aluminum, suggesting that voids and oxides along interfaces throughout the build may be inhibiting thermal diffusion through thermal contact resistance across the interface.

Originality/value

This work systematically analyzed the thermal profiles that develop during the UAM process. The simultaneous heating phenomenon presented here has not been documented by other research programs. The findings presented here will enable future researchers to develop more accurate models of the UAM process, potentially leading to improved UAM bond quality.
Enhancing aerospace engineering students' learning with 3D printing wind‐tunnel models
Authors: Kroll Ehud , Artzi Dror
Published: August 2011

Purpose

The purpose of this paper is to present the benefits offered by rapid prototyping (RP) models for wind‐tunnel testing as part of fourth‐year aerospace engineering student projects. Ways of overcoming some of the difficulties associated with the 3D printing technology are also discussed.

Design/methodology/approach

Polymer‐based RP was used to fabricate two‐aircraft models, which included stiffening metallic inserts. Testing in a subsonic‐wind tunnel was carried out and the results compared to analytic performance predictions.

Findings

Low‐cost rapid prototypes of wind‐tunnel models yielded satisfactory aerodynamic performance. The savings in acquisition cost and time allowed incorporating actual testing in the aircraft design process within the framework of a tight academic budget and schedule.

Practical implications

Conducting real‐wind‐tunnel testing contributes significantly to the educational experience of students; however, it had rarely been carried out when metal model fabrication was the only option. In contrast, RP facilitates an enhanced and more realistic learning experience by offering a quick and affordable means of model manufacturing.

Originality/value

Simple methods of reinforcing polymer‐based models were incorporated, thus presenting an inexpensive way to test and evaluate preliminary aircraft designs, in both academia and industry.
Catalyst‐free growth and characterization of ZnO nanoscrewdrivers prepared by thermal evaporation
Authors: Chuah L.S. , Hassan Z. , Tneh S.S. , Ahmad M.A. , Mohd Bakhori S.K. , Yusof Y.
Published: August 2011

Purpose

The purpose of this paper is to propose a simple physical evaporation route in which catalyst‐free zinc oxide (ZnO) nanoscrewdrivers were deposited on silicon (Si) (111) substrates.

Design/methodology/approach

Prior to the deposition, the Si (111) wafer was cut into pieces of 2×2 cm2. Then, the wafers were dipped for 1 min into mixture buffered oxide etchant to remove native oxide. Then, the samples were rinsed in an ultrasonic bath cleaned with boiling acetone, ethanol, and de‐ionized (DI) water for 10 min. Lastly, the wafers were rinsed in 25 ml DI water in stirred and then were blown dry with nitrogen. In this technique, the starting material is high‐purity metallic zinc (Zn) powder (99.99 per cent pure). Following, the Zn films were then annealed under air environment in the furnace at 500°C for 1 h deprived of any catalysts.

Findings

These ZnO samples were studied by scanning electron microscopy, high‐resolution X‐ray diffraction (HR‐XRD), and photoluminescence (PL) spectroscopy. Atomic force microscope (AFM) images were applied to ascertain surface morphology of produced ZnO nanoscrewdrivers. XRD pattern confirmed that the ZnO nanoscrewdrivers were of polycrystalline structure in universe with a hexagonal close packed type and c‐axis is perpendicular to the substrate. The peak at 34° correspond to the reflection planes of ZnO(002) crystallographic plane is perceived. The AFM surface images disclosed that the surfaces of produced ZnO thin films are not smooth. The PL spectrum of as‐synthesized nanoscrewdrivers shows a UV emission peak at 380 nm and a broad green emission peak at 500 nm.

Originality/value

The paper reports on a simple physical evaporation route, ZnO nanoscrewdrivers were synthesized via the thermal evaporation of the high‐purity Zn powders and annealed at 500°C under air atmosphere without introducing any hetero‐metal catalysts or other carrier gases approach.
Effect of sputtering time on physical and electrical properties of ZrOx thin film on Si
Authors: Tedi K. , Cheong K.Y. , Lockman Z.
Published: August 2011

Purpose

The purpose of this paper is to report the effect of sputtering time on the electrical and physical properties of ZrOx. ZrOx (measured thickness is ranging from 20.5 to 51.3 nm) thin films as gate oxide materials are formed by metal deposition at different sputtering time and thermal oxidation techniques.

Design/methodology/approach

Zirconium is deposited on silicon substrate at three different sputtering time; 30‐, 60‐ and 120‐s continued with an oxidation process conducted at 500°C for 15 min to form ZrOx thin films. High‐resolution X‐ray diffraction (HR‐XRD), Fourier transform infrared (FTIR) spectroscopy and electrical characterizations were used to examine the properties of the thin film.

Findings

A broad ZrOx peak lies in between 26° and 31° from HR‐XRD is presumed as the effect of small thickness of ZrOx and or the ZrOx is still partially crystalline. FTIR spectroscopy results suggested that besides ZrOx, SiOx interfacial layer (IL) has also formed in all of the investigated samples. As the sputtering time increases, hysteresis between the forward and reverse bias of capacitance‐voltage curve has reduced. The lowest leakage current density and the highest oxide breakdown voltage have been demonstrated by 60‐s sputtered sample. These may be attributed to a lower effective oxide charge and interface trap density. The extracted dielectric constant (κ) of these oxides is ranging from 9.4 to 18, in which the κ value increases with the increase in sputtering time.

Originality/value

ZrOx thin film which was fabricated by sputtering method at different sputtering time and thermal oxidation techniques showed distinctive electrical results. SiOx IL formed in the samples.
Parametric study of efficient thermal dissipation in an LED back light unit
Authors: Taek Kim Jin , Ro Lee Cheul , Kim Daesuk , Joon Baek Byung
Published: August 2011

Purpose

Thermal management under high heat flux is crucial to developing high‐power light‐emitting diode (LED) applications. The purpose of this paper is to propose an efficient thermal dissipation technique for an LED back light unit (BLU) system.

Design/methodology/approach

A typical BLU system includes an LED package (GaN on sapphire, cathode/anode, silicone encapsulant, resin plus phosphor) on a printed circuit board (PCB), a light guide panel, and an aluminum cover frame. The temperature distribution of this system has been simulated and the thermal behavior within a 3D model has been investigated using a commercial computational fluid dynamic code (FLUENT 6.3).

Findings

The authors examined the heat‐spreading effect of cover lengths ranging from 6 to 300 mm and also observed the effect of back cover thickness on the junction temperature and cover frame temperature and investigated the influence of the air gap between the package and the cover frame. Removing the air gap lowers the maximum temperature by about 6 percent. It was found that the addition of a copper layer covering the external surfaces of the LED chip enhanced the cooling efficiency. Finally, the maximum junction temperature can be decreased by more than 21 percent in the range of parameters considered by removing the air gap, adding a heat spreader, and using a thick cover frame.

Originality/value

In this paper, thermal management for efficient heat spreading through a typical BLU system without using any additional devices is investigated. Several parameters that increase the system's temperature are examined, and a combination of design features that attenuate the junction temperature is proposed.
Deformations in stretched surface mounted ceramic strips for sensor applications
Authors: Gschohsmann Walter , Nicolics Johann , Suhir Ephraim
Published: August 2011

Purpose

The purpose of this paper is to present a most accurate analytical model suit for the prediction of the elastic displacements in a ceramic strip for sensing longitudinal deformations. Accordingly, the objective of the analysis given is to develop a physically meaningful and simple‐as‐possible stress‐strain model for an elongated strip attached to a thick‐and‐stiff substrate.

Design/methodology/approach

Today's advanced strain gage designs intended for measuring deformations and related physical characteristics use sensitive elements manufactured as ceramic strips. The output signal depends to a great extent on the ability to measure and to adequately interpret the induced elastic displacements in the strip, as the global electric resistor is coupled strongly to the strain field in the sensitive layer. The dependence of the strain on the thickness of a strip is calculated using an analytical 2D stress‐strain model using a shear tension applied at its interface with the substrate and zero‐stress at the opposite face as boundary conditions. All necessary considerations and calculations to develop the model are discussed.

Findings

A significant result is the gradual reduction in the deformation depending on the layer thickness. Applying the model combines easy numerical effort with an expressive approximation.

Originality/value

The developed model can be used in the analysis and physical design of the structural elements of the type in question, not necessarily in the field of strain gage and sensor engineering.
Polysilicon nanogap structure development using size expansion technique
Authors: Hashim Uda , Taib Nazwa , Dhahi Thikra S. , Saifullah Azizullah
Published: August 2011

Purpose

Nanobiosensors based on nanogap capacitor are widely used for measuring dielectric properties of DNA, protein and biomolecule. The purpose of this paper is to report on the fabrication and characterization polysilicon nanogap patterning using novelties technique.

Design/methodology/approach

Overall, the polysilicon nanogap pattern was fabricated based on conventional lithographic techniques. For size expansion technique, by employing simple dry thermal oxidation, the couple of nanogap pattern has been expanded to lowest nanogap value. The progress of nanogap pattern expansion was verified by using scanning electron microscopy (SEM). Conductivity, resistivity, and capacitance test were performed to characterize and to measure electrical behavior of full device fabrication.

Findings

SEM characterization emphasis on the expansion of polysilicon nanogap pattern increasing with respect to oxidation time. Electrical characterization shows that nanogap enhanced the sensitivity of the device at the value of nano ampere of current.

Originality/value

These simple least‐cost method does not require complicated nanolithography method of fabrication but still possible to serve as biomolecular junction. This approach can be applied extensively to different design of nanogap structure down to several nanometer levels of dimensions. A method of preparing a nanogap electrode according to the present innovation has an advantage of providing active surface that can be easily modified for immobilizations of biomolecules.
Thick‐film photoimageable and laser‐shaped arms for thermoelectric microgenerators
Authors: Markowski Piotr
Published: August 2011

Purpose

The purpose of this paper is to investigate the possible application of thick‐film, metal‐based thermocouples to microsystems power supply. The subject of matter was development of the procedure of thick‐film thermopile miniaturisation.

Design/methodology/approach

The aptitude of four photoimageable inks (based on silver or silver‐palladium) to fabrication of miniaturised thermocouples' arms was investigated. The object of interest was their compatibility with different kinds of low temperature cofired ceramic (LTCC) substrates, maximum resolution, shrinkage and electrical resistivity. Usage of the laser shaping technique to fabrication of narrow thermocouples' arms was also subject of matter. After tests and processes optimization both techniques were combined to fabricate the thick‐film Ag/Ni microthermopile.

Findings

Most of investigated inks were compatible with all tested LTCC tapes – fired as well as unfired (green tapes). Photoimageable inks technique can be successfully used for thermocouples' arms miniaturization. 40 μm/40 μm line/spaces resolution can be easily achieved. Combining this technique with laser shaping enabled microthermopile fabrication. It consisted of 42 Ag (photoimageable)/Ni (laser shaped) thermocouples. Arms width was 40 μm and 225 μm (Ag‐ and Ni‐arm, respectively), spaces between them – 65 μm. Overall, width of single thermocouple was smaller than 0.4 mm.

Practical implications

Fabrication of microthermopile consisting of several hundreds of thick‐film thermocouples will be possible if described procedure is applied. Such microgenerator will generate output power sufficient to supply some microsystems or microelectronic circuits.

Originality/value

The properties of four photoimageable inks were investigated as well as their compatibility with five different LTCC substrates (fired and unfired). Procedure of thick‐film microthermopile fabrication using photoimageable inks technique combined with laser shaping was proposed for the first time.
An analysis of value management in practice: the case of Northern Ireland's construction industry
Authors: Perera Srinath , Hayles Carolyn S. , Kerlin Stephen
Published: August 2011

Purpose

The purpose of this paper is to report the findings of research into the principles and procedures associated with value management (VM) and assess its use and effectiveness within the construction industry in Northern Ireland. It provides a brief review of the principles, various procedures and methods associated with VM, investigates the positive and negative factors relating to its use whilst analysing the extent of its usage and determining its effectiveness.

Design/methodology/approach

Using a mixed method approach, the authors present the results of a survey of construction professionals operating in Northern Ireland and provide an examination of three case studies exploring the use of VM within the Northern Ireland construction industry.

Findings

In an industry where the client's needs and demands are of paramount importance, VM has emerged as a tool which can help satisfy these needs. This study shows that VM is frequently used within the Northern Ireland construction industry and on the whole is quite effective. However, the research exposed a general consensus that the VM process is frequently not implemented at the most appropriate stage of a project, which suggests that if it was, it could perhaps be more effective than it is at present. There is an apparent lack of formal methods used to carry out the VM process. Instead, rather loose and informal methods are used.

Originality/value

In the absence of a similar study that analyses the factors that influence the VM process highlighting and documenting the views and opinions expressed by the professionals within today's industry and reviewing the effectiveness of its usage, this paper documents a snapshot of practice of VM within the Northern Ireland construction industry.
Evaluating development and community benefits of shopping malls
Authors: Musil Thomas A.
Published: August 2011

Purpose

The purpose of this paper is to focus on the real estate development and community interaction aspects of US shopping malls. The existing research on shopping mall development and redevelopment can more comprehensively address the importance of malls to the communities in which they are located. Existing shopping mall research focuses on lease valuation, tenant location, retail agglomeration economies, retail demand externalities and intangible asset value. Largely, neglected areas of research are the community and economic contributions of shopping malls. These are critical issues given the age of shopping malls worldwide, the need for adjacent area redevelopment and requirement of large public subsidies for infrastructure construction.

Design/methodology/approach

This paper investigates the critical role of shopping malls as town centres and catalysts for area development and redevelopment. A review of the existing research on shopping malls and retail economic contributions to communities is addressed along with how mall redevelopment can be a catalyst for the revitalization of urban core and suburban areas. Methodology on the measurement of shopping centre economic and employment impacts using input/output (IO) modelling is reviewed and analysed.

Findings

IO modelling is an effective tool to evaluate publically supported infrastructure to accompany shopping mall and retail redevelopment. As an example of an IO analysis of construction and mall operations economic impacts, the paper presents a case study of the proposed $2 billion Mall of America (Bloomington, Minnesota) expansion employing IO modelling.

Originality/value

The paper demonstrates the community benefits and economic justification for public support for mall revitalization and provides a reliable analytical tool for quantifying the benefits of mall redevelopment to the community.
A contingent valuation model for assessing electricity demand
Authors: Otegbulu Austin C.
Published: August 2011

Purpose

The purpose of this paper is to focus on households' willingness to pay for electricity consumption and mitigation expenditure due to poor electricity infrastructure as a measure of demand and tariff setting.

Design/methodology/approach

In this paper, the demand side management (DSM) approach was adopted in establishing user demand for electricity in the study area.

Findings

Based on the high cost (averting expenditure) of providing alternative power supply, households are willing to pay extra for more reliable and regular power supply.

Practical implications

The study is a deviation from the usual command or supply side management approach to infrastructure provision and management.

Originality/value

There is limited research on DSM approach to electricity infrastructure provision in Nigeria. The study will enhance the chances of cost recovery under private‐public partnership arrangement. The paper identifies that a reliable and reasonable priced electricity supply is essential for a developing country.
Measuring the financial performance of green buildings in the UK commercial property market
Authors: Fuerst Franz , McAllister Patrick , van de Wetering Jorn , Wyatt Peter
Published: August 2011

Purpose

Given the centrality of data and information to the evaluation and operation of policies to reduce carbon emissions, the purpose of this paper is to investigate potential sources of data within in the UK on the commercial building stock in terms of its physical characteristics, financial performance, energy consumption and environmental performance. The research aimed to increase understanding of the potential sources of data on property attributes, financial performance and energy use or environmental performance, with a particular emphasis on evaluating their strengths and weaknesses in terms of scope, quality, availability and practicability.

Design/methodology/approach

This is an explorative, qualitative study that uses semi‐structured interviews conducted with 11 different data holding organisations.

Findings

Whilst public sector organisations have the potential to provide the data required for large samples, there are major barriers to obtaining and linking the different databases. Data on the three key data elements (prices, attributes and environmental performance) tend to be split between different governmental agencies. There are likely to be substantial problems (and costs) of linking the databases due, in particular, to definitional differences. There is a conflict between government's public good objective of increasing knowledge of the environmental performance of buildings and its objective of maximising revenues from the commercial exploitation of data. Since the private sector organisations that hold data are commercially motivated, the samples that they have gathered are largely client driven and, consequently, tend to be partial, particular, proprietary, private and product‐related.

Originality/value

Since pricing studies are central to evaluating the effectiveness of eco‐labelling in property markets, this paper improves one's understanding of the role of information and data barriers to improving the allocative efficiency of commercial property markets.