bluuebunny/crossref_metadata_2025 huggingface dataset:
Infusing a Teacher Preparation Program in Learning Disabilities with Assistive Technology
Authors: Bryant Diane Pedrotty , Erin Jane , Lock Robin , Allan James M. , Resta Paul E.
Published: December 2008

A recent trend in the fields of special education, rehabilitation, and technology is the development and implementation of assistive technology (AT) devices and services to assist individuals in compensating for disabilities and/or utilizing functional capabilities to meet environmental demands. AT devices and services have major implications for individuals with learning disabilities (LD) regarding life span issues, environmental and curricular accessibility, and compensatory strategies. Faculty members in higher education who are responsible for designing teacher preparation programs in LD must explore ways to structure curricula, methodologies, and practica to better prepare teachers to work with students who use AT devices to compensate for their specific learning disabilities. The purpose of this article is to describe curriculum design steps and barriers to and solutions for infusing LD teacher preparation programs with assistive technology.
EEG Power Spectra of Adolescent Poor Readers
Authors: Ackerman Peggy T. , McPherson W. Brian , Oglesby D. Michael , Dykman Roscoe A.
Published: December 2008

EEG power spectra were studied in two poor-reading adolescent groups (dysphonetic and phonetic) as the students viewed strings of letters and easy words (seven categories). The students ranged in age from 12 to 16 years; 29 were male, 9 were female. Bilateral results are reported from frontal, parietal, and occipital regions. Significant Group × Hemisphere effects were found in the alpha and beta bands, with the phonetic group showing right greater than left asymmetry. This finding was interpreted to reflect more circumscribed and mature processing in the phonetically abler poor readers, given that normally reading adults typically show right greater than left asymmetry in word tasks. Overall, the dysphonetic group had higher beta power than the phonetic group, which may reflect greater effort.
An Evaluation of the Dyslexia Training Program
Authors: Oakland Thomas , Black Jeffrey L. , Stanford George , Nussbaum Nancy L. , Balise Raymond R.
Published: December 2008

The development of reading and spelling skills in students with dyslexia, by definition, is delayed and often remains delayed despite years of instruction. Three qualities are thought to facilitate reading development in these children: the provision of a highly structured phonetic-instruction training program with heavy emphasis on the alphabetic system, drill and repetition to compensate for short-term verbal memory deficits, and multisensory methods to promote nonlanguage mental representations. The Dyslexia Training Program, a remedial reading program derived from Orton-Gillingham methods, embodies these qualities. Following their 2-year program, students displaying dyslexia demonstrated significantly higher reading recognition and comprehension compared with a control group. The two groups did not differ in spelling. In addition, the degree of improvement in reading demonstrated by students who received the Dyslexia Training Program by videotape and by those who received it live from instructors did not differ.
Loneliness and Coherence Among Preschool Children with Learning Disabilities
Authors: Margalit Malka
Published: December 2008

This study investigated loneliness and coherence among Israeli preschool children with learning disabilities, in an attempt to identify the sources of social deficits before academic failure was established. The sample consisted of 187 preschool children divided into three groups: (a) 60 children at high risk for developing learning disabilities (LD) in six mainstreamed preschool settings (47 boys and 13 girls), (b) 76 nonhandicapped peers from the same preschools (56 boys and 20 girls), and (c) 51 children (38 boys and 13 girls) at high risk for developing LD who were regular students at 17 preschools and received special help in the afternoons outside their educational settings, at a regional learning center for students with LD. The research instruments consisted of the Children's Sense of Coherence Scale, the Loneliness Scale, a peer nomination procedure, and teachers' ratings. Two-way MANOVAs demonstrated that the two groups of children (Groups [A] and [C]) with LD and with a high risk for developing learning disabilities experienced higher levels of loneliness and lower levels of coherence. A subgroup examination revealed that they were less accepted by nondisabled peers and had less reciprocal nominations. Furthermore, their teachers viewed them as showing more maladjustment.
Special Education in Russia
Authors: Korkunov Vladimir V. , Nigayev Alexander S. , Reynolds Lynne D. , Lerner Janet W.
Published: December 2008

Special education in Russia is undergoing major change. It is shifting from a system that was first established under the Soviet communist regime over 70 years ago to one that reflects a more humanistic view of children with disabilities. To describe special education in Russia, this article (a) explains the background information on the formation of a Russian-American partnership, (b) offers an historical perspective of special education in Russia, (c) reviews the current status of special education in Russia and in particular the Sverdlovsk Oblast, and (d) forecasts future directions of Russian special education. In considering new goals and future directions for special education in Russia, the authors suggest that the policies and legislation developed by the Provinces in Canada may offer a workable model for a Russian special education system.
Job Satisfaction of College Graduates with Learning Disabilities
Authors: Witte Raymond H. , Philips Lois , Kakela Megan
Published: December 2008

Job satisfaction, as assessed via five scales that posed questions concerning colleagues, work, supervision, pay, and promotion, as well as overall total job satisfaction, was examined for 55 self-identified college graduates with learning disabilities (LD) and 55 control graduates matched by gender, major, degree, and graduation year. All participants graduated from a competitive midwestern university from 1987 to 1994 and represented advantaged groups when compared to both LD and non-LD populations. The graduates with LD required significantly more time to complete their degrees and showed significantly lower GPAs. Data analysis indicated that the graduates with LD perceived themselves as receiving significantly less pay and promotion opportunities, and reported less total job satisfaction, than graduates without LD. However, no significant salary differences between the groups were found. The implications of these findings are examined.
The Metaphor of Scaffolding
Authors: Stone C. Addison
Published: December 2008

Over the past 20 years, an increasing number of psychologists and educators have used the notion of scaffolding as a metaphor for the process by which adults (and more knowledgeable peers) guide children's learning and development. The purpose of the present article is to provide a critical analysis of the scaffolding metaphor, with particular emphasis on its applications to the case of atypical learners. In the initial sections of the article, the origins and early applications of the metaphor are sketched. With this as background, criticisms of the metaphor raised by others are reviewed, and a proposal for an enriched version of the metaphor is presented. At the heart of the proposed revision is an emphasis on the communicational dynamics and conceptual reorganization involved in adult—child interactions. With an enriched metaphor as a frame, the next section reviews applications of the scaffolding metaphor to the study of parent—child interactions and teacher—student instructional activities involving children with learning disabilities. The strengths and limitations of this work are evaluated, and proposals are made for how to reap further benefits from applications of the scaffolding metaphor to analyses of the development and instruction of children with learning disabilities.
In Search of the Architect of Learning
Authors: Butler Deborah L.
Published: December 2008

In this article, I accept Stone's invitation to reevaluate the metaphor of scaffolding, building on his helpful analysis. Specifically, I identify what has been appealing about the scaffolding metaphor by describing how, as an intervention researcher working with students with learning disabilities, I have used the metaphor to describe a specific instructional approach in my own research. Then, I revisit and critique scaffolding as an instructional metaphor. I also comment on Stone's assertion that a more explicit description of communicative interchanges is required to more clearly describe instructional scaffolding. Finally, I conclude that the scaffolding metaphor is fundamentally flawed and advance an alternative view that may more successfully promote correspondence between instructional activities and our emerging vision of the dynamics of teaching and learning.
Scaffolding
Authors: Reid D. Kim
Published: December 2008

To situate the concept of scaffolding within a broader context than that addressed by Stone, I discuss it with respect to (a) the historical context of learning disabilities, (b) the emerging focus on learners activity, (c) the reification of learning disabilities, and (d) the unintended effects that frequently occur as a by-product of injudicious (and often unintentional) scaffolding. I conclude that the effective practice of special education has been inhibited by our isolation of interventions from the theories that give rise to them, and by the way we structure teacher education. Although scaffolding is not the answer to correcting these problems, it may serve to refocus our attention and efforts in useful ways.
Conversational Maxims and Scaffolded Learning in Children with Learning Disabilities
Authors: Donahue Mavis L. , Lopez-Reyna Norma A.
Published: December 2008

In our commentary on Stone's (this issue) article on the metaphor of “scaffolding,” we propose (somewhat tongue-in-cheek) the “flying buttress” as an improvement. Unlike a scaffold, the buttress symbolizes a nontemporary architectural device that begins as a support to building new knowledge on an existing foundation, but then itself becomes an integral and evolving part of the new structure. We then analyze scaffolded instruction as a kind of conversation that depends on rather sophisticated shared assumptions about the agenda and the rules underlying the process of the conversation, including an understanding of when these rules are suspended. We present evidence that some children with language/learning disabilities may not benefit from scaffolded instruction because they (a) follow a different agenda during instructional discourse (e.g., to camouflage their lack of comprehension); and (b) overrely on the default Gricean Maxims that cooperative speakers always make an effort to be informative, truthful, relevant, and clear.
An Item Response Theory Analysis of the Conners Teacher's Rating Scale
Authors: Gumpel Thomas , Wilson Mark , Shalev Ruth
Published: December 2008

We used an item response theory (IRT) measurement model to examine the 28–item Conners Teacher's Rating Scale (CTRS) for the diagnosis of attention-deficit/hyperactivity disorder (ADHD). Using an Israeli sample of 453 pairs of respondents (parents and teachers), we broke down our sample into nonclinical (n = 306) and clinical (n = 147) subsamples. IRT analyses based on a rating scale model revealed structural inadequacies involving the apparent inappropriateness of the 4-point Likert-type scale used by the CTRS. Additionally, IRT analyses were able to shed light on differences in the structure of the latent trait for the ADHD variable as measured by the CTRS for all four groups of respondents. Implications for the diagnosis and treatment of ADHD are presented.
Sleep Disturbances in Children with Attention-Deficit/Hyperactivity Disorder
Authors: Ring Aliza , Stein Daniel , Barak Yoram , Teicher Aharon , Hadjez Jack , Elizur Avner , Weizman Abraham
Published: December 2008

The sleep profiles of 13 children with attention-deficit/hyperactivity disorder (ADHD) who were treated with a fixed dose of methylphenidate for at least 1 month were compared with those of 16 healthy siblings. Sleep disturbances were assessed according to a structured sleep questionnaire, and the severity of ADHD was evaluated via the Conners Parents Teachers Rating Scale. The results indicated that significantly more children with ADHD demonstrated single or multiple sleep disturbances as well as higher rates of specific sleep disorders, such as initial and middle insomnia, compared with their siblings. No correlation was found between the severity of ADHD and disturbed sleep. Sleep duration and satisfaction with sleep were similar in the two groups. These findings raise important questions regarding the association between ADHD and disturbed sleep.
Evaluating Medication Response in ADHD
Authors: Hale James B. , Hoeppner Jo-Ann B. , DeWitt Mary Beth , Coury Daniel L. , Ritacco David G. , Trommer Barbara
Published: December 2008

Although evidence supports the use of double-blind placebo medication trials to evaluate methylphenidate (MPH) effects on the core behavioral symptoms of attention-deficit/hyperactivity disorder (ADHD), few studies have demonstrated their utility in examining MPH effects on the cognitive deficits associated with ADHD. This article presents a technique for evaluating behavioral and cognitive dose-response relationships at the single-subject level of analysis. Case study results and multivariate analyses suggest that systematic evaluation of behavioral and cognitive MPH dose-response relationships could lead to more accurate MPH titration and greater long-term multimodal treatment efficacy.
Covalent Modification of the Wool Fiber Surface: The Attachment and Durability of Model Surface Treatments
Authors: Meade Susie J. , Caldwell Jonathan P. , Hancock Anita J. , Coyle Katie , Dyer Jolon M. , Bryson Warren G.
Published: December 2008

Exposure of reactive chemical functional groups through controlled surface lipid removal provides a means for covalent attachment of novel molecular entities to the wool fiber surface. Cleavage of the dominant lipid in the epicuticle, 18-methyleicosanoic acid (18-MEA), from the underlying proteinaceous layer was employed, prior to further surface modification, by means of aqueous hydroxylamine treatment. Treatments utilizing covalent bonding to the surface through thiol, carboxyl, amine, or other reactive chemical groups offer improved durability to textile processing, such as dyeing and laundering. This surface modification investigation compared and assessed the attachment and durability of various wool fiber surface modification technologies and provided proof of principle for the manipulation of surface properties via covalent attachment of treatment compounds, providing enhanced fiber performance. Following removal of the surface lipid layer, wool fibers were modified using fluorescent and hydrophobic compounds and micro and nanoparticles. The extent of modification was assessed using scanning electron, light, and fluorescence microscopy, wettability testing and X-ray photoelectron spectroscopy (XPS). Surface treatments were evaluated with regard to effectiveness and durability to dyeing and laundering. Surface modification via attachment to thiol and other nucleophilic functionalities was observed to be greatly improved after hydroxylamine treatment, demonstrating the advantage of a customized exposed and accessible surface before secondary treatment. Increased durability and effective microparticle attachment was best accomplished employing zero or short-range crosslinking mechanisms, with zero-length attachment enhanced with the use of the crosslinking promoters, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC) and N-hydroxysuccinimide (NHS). Fluorescent and hydrophobic surface modifications exhibited high durability to laundering and demonstrated the viability of customizing surface hydrophobicity.
In the Eye of the Impulsive Beholder
Authors: Jones Shayne , Lynam Donald R.
Published: December 2008

Substantial evidence indicates that impulsivity is a robust correlate of offending. However, its effects appear to be partially contingent upon other criminological factors, such as neighborhood context. The research examining the moderating influence of neighborhoods on the impulsivity—offending relationship has yielded inconsistent findings. The current analysis further investigates the possible interaction by exploring different types of impulsivity-related traits, perceptions of neighborhood informal social control, and their interaction among young women and men. Results indicate that thrill and adventure seeking (among men) and lack of premeditation (among men and women) exert stronger influences on offending among those who live in neighborhoods low in perceived supervision. These findings have implications for criminological theories and intervention efforts.
Simulation of building drainage system operation under water conservation design criteria
Authors: McDougall J.A. , Swaffield J.A.
Published: December 2008

The Water Supply (Water Fittings) Regulations 1999, introduced to encourage innovation and water conservation, will profoundly affect building drainage design. Reduced shower flows and washing machine volumes and 6/3 litre dual flush wc operation will lower through flows, while drop valve wc flushing will affect system operation. Design for water conservation will necessitate the prediction of wave attenuation and its impact on solids transport and, without the safety factor provided by higher throughflows, simulations will ensure efficient design for minimal solid deposition. A simulation employing the method of characteristics solution of the St Venant equations and empirical relationships between solids velocity and the surrounding flow conditions is presented to predict solids transport performance within networks specified by slope, diameter, material, and appliance distribution and discharge characteristics.
Comparison of peak load predictions and treatment of solar gains in the admittance and heat balance load calculation procedures
Authors: Rees S.J. , Spitler J.D. , Holmes M.J. , Haves P.
Published: December 2008

Calculation of design cooling loads is of critical concern to designers of HVAC systems. The work reported here has been carried out under a joint ASHRAE-CIBSE research project to compare design cooling calculation methods. Peak cooling loads predicted by the ASHRAE heat balance method are compared with those predicted by a number of implementations of the admittance method using different window models. The results presented show the general trends in overprediction or underprediction of peak load. Particular attention is given to different window modelling practices. The performance of the methods is explained in terms of some of the underlying assumptions in the window models, and by reference to specific inter-model comparisons.
Use of computational fluid dynamics to aid studies of room air distribution: A review of some recent work
Authors: Russell M.B. , Surendran P.N.
Published: December 2008

Computational fluid dynamics has a wide range of application in the study of room air distribution. The application is providing valuable guidance for those interested in such areas as comfort, productivity and sick building syndrome. This paper gives a comparative review of some of the work undertaken in the field and highlights some of the modelling assumptions noted within the literature. It is apparent from the review that the use of the CFD methodology is helping to develop our understanding of internal ventilation flows, yet it is also apparent that many investigations are currently employing modelling assumptions that will hinder the development of generic guidance from such investigations.
Developments in the definition of fluid traction forces within building drainage vent systems
Authors: Jack L.B.
Published: December 2008

With developments in the understanding of the pressure regime generated within single-stack building drainage systems, analysis by numerical modelling of complex and detailed systems serving a wide range of sanitary appliances has progressed notably. Computer-based finite-difference simulations incorporate both the complex unsteady fluid flow principles inherent within such systems and the specific design details of the drainage network, thereby allowing the time-dependent pressure response of the system to be assessed and the appliance trap seal retention or depletion to be predicted. This paper develops a new approach to the way in which the fluid flows present within the system are modelled, by providing an enhanced analysis of the waste water and entrained air flow interaction. It also extends the applicability of empirical data and examines resultant friction factor data. This approach can be applied to both single and multiple inlet vertical stack flow and can significantly enhance the designer's ability to predict system response. Combined with unsteady free surface horizontal pipe flow theory, this enables the complete drainage network, from appliance trap through branch connections, vertical stacks and the sewer connection, to be analysed.
Passive solar houses: Availability of weather suitable for calibration in the UK
Authors: Lowe R.J. , Gibbons C.J.
Published: December 2008

The work aims to estimate the likely duration of monitoring which will be required to allow reasonably accurate field measurement of the fabric heat loss and effective solar aperture of low-energy and passive solar houses, using the co-heating method. Everett et al have shown that field measurement using this technique requires measurement of the auxiliary energy consumption of the house over a period with a wide range of daily mean insolation. The duration of monitoring necessary to meet this type of criterion has been calculated for monitoring periods starting at various times of the year, using between 6 and 18 years of radiation data for seven UK sites. The results of this project confirm and extend Everett's original results. They show for example that 'rapid thermal calibration projects', which aim to provide reliable characterisation of house performance from a few weeks of intensive monitoring, should ideally be scheduled to start in late winter or in late summer and autumn. These conclusions are not strongly dependent on the precise insolation criteria or on geographic location.
Adiabatic saturation temperature of air: Practical application
Authors: Fitzgerald D.
Published: December 2008

An elementary practical relation is developed for the temperature of air after saturation with water vapour, in terms of its initial conditions, and the fraction of the latent heat of evaporation taken from the initial sensible heat of the air.
Loft insulants: Effect of air speed on thermal performance
Authors: Simpson A. , Stuckes Audrey D , Napora M.
Published: December 2008

Measurements have been carried out in an experimental roof rig, under steady-state temperature conditions, to determine the effect of air speed and direction on the thermal performance of glass fibre and mineral fibre loft insulation. The results show that when subjected to steady air speeds of up to 0.25 ms -1, similar to those encountered in lofts, irrespective of direction of flow, the effective λ-value of the insulants is in close agreement with the values obtained in standard thermal conductivity tests. At higher air speeds the X-value tended to increase significantly with increasing air speed and increasing angle of incidence. It was found that the λ-value can be predicted for transient air flow over the loft insulants by evaluating a 'mean integrated' speed for the air pulses and assuming this to be equivalent to a sustained air speed.
Heat flows from solid ground floors in buildings: Simple calculation model
Authors: Wright A.J.
Published: December 2008

The steady-state methods currently used to calculate floor heat loss are examined, and the errors which these produce in comparison with more accurate analytic solutions are illustrated. A simple model of flow is then proposed, which splits the flow into the three components. These are the steady-state flow and annual cyclic flow to the outside, for which analytic solutions are given, and the short term vertical flows within the floor resulting from internal temperature fluctuations. A worked example is presented for a typical case.
A use for the 'index of profitability'
Authors: Fitzgerald D.
Published: December 2008

The concept of 'index of profitability', used to identify optimal investment options, is developed to provide a test for the optimal amount of investment on each option.
Solar irradiation database for the United Kingdom
Authors: Muneer T. , Satuja G.S.
Published: December 2008

The motivation for collating data on solar irradiation intercepted by inclined and vertical surfaces is given; the information is of interest to building services engineers, architects, agriculturalists and others. Details are given of UK stations measuring horizontal hourly diffuse and global irradiation, and day-integrated diffuse and global irradiation.
Monthly mean solar irradiation availability for the United Kingdom
Authors: Muneer T.
Published: December 2008

The CIBSE Guide provides monthly and annual means of the daily solar irradiation for surfaces of five orientations. However, the data are provided for only one site in south-east England. In this work a validated anisotropic model for the diffuse radiance is used in conjunction with measured hourly horizontal irradiation data to generate average daily irradiation tables for seven sites covering most of England, Wales and Scotland.
Performance lines and energy signatures: Review and analysis
Authors: Levermore G.J. , Chong W.B.
Published: December 2008

The paper briefly reviews monitoring and targetting and the impact of the building energy management system. Energy signatures and performance lines are then examined. From the analysis of a performance line a statistical 'performance index' of control quality is proposed. The influence of controls, solar radiation, net radiation, and wind on the performance line is then considered, using degree days as the only weather parameter. Examination of a well monitored school, using these degree day algorithms, revealed that very little solar gain was utilised, probably because of the limited control.
Science and Engineering Research Council Research Reports
Authors: Building Serc
Published: December 2008

The article gives a list of current research projects in building services engineering funded by the SERC Building Subcommittee. Listed are those current projects which are most likely to be of interest to building services engineers. Research workers would welcome any comments or enquiries on their projects.
Domestic kitchen exhaust systems: Performance assessment
Authors: Riffat S.B.
Published: December 2008

A microprocessor-controlled tracer gas system was used to measure ventilation and interzone air movement in a house equipped with a wall-mounted hood and a kitchen extract fan. The air velocity profile under the wall-mounted hood was also measured using a hot-wire anemometer. The results indicated that extract rates of typical kitchen exhaust systems are significantly lower than that recommended by the British Standards Code of Practice BS5250. The airflow velocity measurements showed that the wall-mounted hood unit has a low capture efficiency at the cooking surface and that the performance of the hood in this region is mainly dependent on the effect of thermal buoyancy. The exhaust systems tested were unable to prevent airflow at high rates from the kitchen to the living space through an open doorway, even at small interzone temperature differences. Significant movement of moisture and other cooking contaminants from the kitchen to the adjacent rooms would occur under these conditions.
Ventilation performance of large buildings: Prediction using pressurisation measurements
Authors: Perera M D A E S , Powell G. , Walker R.R. , Jones P.J.
Published: December 2008

This paper provides a model which uses whole-building leakage measurements to predict the ventilation performance of buildings and illustrates its use by applying it to a large, industrial building. Air leakage measurements with the building 'as found' and then with its loading doors sealed showed a 14% reduction at an inside/outside pressure differential of 25 Pa. Using these leakage characteristics, the model predicted ventilation rates which corresponded well with measured values. Meteorological data at the site for the heating season were combined with the ventilation characteristics of the building (given by the model) to predict the ventilation performance of the building over that period. The results indicated that the building 'as-found' would have, on average, an air change rate of 0.5 h-1 which reduces by 24%, i.e. to 0.38 h-1, when the loading doors are made airtight. Calculations also indicate that such a retrofit measure would reduce by 14% the total energy required for space heating over that period.
Control strategy: Adjusting chiller outlet water temperature for energy savings
Authors: Ho W.F.
Published: December 2008

A control strategy for the chiller outlet water temperature reset of a chiller plant with the objective of saving energy was developed. The reset scheme was verified against a hypothetical air conditioning plant which supplied conditioned air to a large single room. The dynamic mathematical models of the hypothetical air conditioning system and the room developed in References 1 and 2 were used in the study. These dynamic mathematical models were simulated and set up on an analogue computer which was linked to a digital computer where the reset scheme was programmed and implemented. The dynamic behaviours of the hypothetical air conditioning plant and the room were monitored and used by the digital computer for the reset scheme. In the reset scheme, the effects of the airside control valve position, the room temperature and the time interval for the chiller outlet water temperature setpoint increment or decrement were investigated. The objective function used in the reset scheme was found to be: 0.08 room temperature error + 1.64 (0.75 - control valve position), indicating the dominance of the airside control valve position in the reset scheme.
High-effectiveness fan convector heaters: Prediction of thermal performance
Authors: Brinkworth B.J. , Tough M.C.
Published: December 2008

New applications for fan convectors require them to operate with lower inlet temperatures than in conventional wet systems and with a greater temperature drop, and consequently a higher effectiveness. A model is presented which allows performance to be predicted accurately for these conditions. It is suitable for incorporation into system performance models and provides a reliable basis for manufacturers to estimate the output of families of convectors based on a minimum of test work to determine two critical coil parameters.
A review of some methods for calculating internal longwave radiation exchange in buildings
Authors: Davies M.G.
Published: December 2008

This paper draws attention to certain features in motivation and in structure regarding methods of estimating radiant exchange in a room as reported in a recent article. Many results prove to be independent of choice of surface temperatures. Some simplified methods amount to transforming a surface-to-surface pattern of exchange to a surface-to-star point pattern.
Building pressure coefficients: Application of three-dimensional CFD methods to prediction
Authors: Shao L. , Sharples S. , Ward I.C.
Published: December 2008

Wind-induced pressure coefficients are required for evaluating the energy performance of existing buildings, validating new building designs and, most recently, for multizone air flow computer models as input data. However, the traditional method of obtaining pres sure coefficients, by experiment, is time consuming, expensive and not amenable to parametric changes. Work with an existing computational fluid dynamics (CFD) code, FLUENT, has been carried out for the new application of predicting building pressure coefficients. The equations describing three-dimensional, turbulent flow fields around a building are solved using a finite difference technique. Comparison between experimental data and those of the CFD program showed good agreement. In addition, it is much more efficient and economical. To demonstrate the flexibility of the CFD model, a new design concept was also examined; this shows that building a through slot in the middle of a high-rise building reduces the wind induced pressure and thus the rate of air infiltration.
Thermal targets of the CIBSE Energy Code Part 2(a): Effect of changes in the Building Regulations (1990)
Authors: Harrington-Lynn J.
Published: December 2008

Some ten years ago the CIBSE published a code on the thermal energy targets for heated and naturally ventilated buildings. An analysis of the CIBSE Building Energy Code shows that there is no apparent need to revise its thermal targets to take account of the changed requirements for energy conservation contained in the 1990 edition of Approved Document L of the Building Regulations (England and Wales).
Atrium sprinkler: Performance analysis
Authors: Chow W.K. , Fong N.K.
Published: December 2008

The performance of an atrium sprinkler is investigated by a crude analysis and a fire field model. In the crude analysis, empirical expressions for the fire plume are used to study the thermal responses of the sprinkler head. In the field model, a set of partial differential equations describing conservation of momentum, enthalpy and mass is solved numerically to predict the airflow pattern, temperature and smoke concentration contours resulting from the fire and a sprinkler water spray. Both approaches indicate that installing sprinklers in a high-headroom atrium would not be effective in controlling fire.
Self-regulating polymeric heating cables : Aging techniques to establish life ratings
Authors: Whitney Wells , Chou Gee Kin
Published: December 2008

Conductive polymer trace heaters are used extensively in the temperature maintenance of hot water service pipework downstream of the boiler. These trace heaters have the unique property of self-regulation; the heaters adjust their power output depending on ambient temperature. The heaters must operate reliably for an accepted lifetime. Design, performance, and accelerated life testing of self-regulating conductive polymer trace heaters are examined.
Third-order lumped-parameter simulation method
Authors: Tindale A.
Published: December 2008

The value and potential accuracy of second-order simplified building thermal models have been established. This paper points out the failings of these very simple models, and describes some straightforward modifications which can significantly improve their accuracy without compromising their simplicity or speed. These modifications include the separate treatment of radiative and convective heat through the rad-air model, the addition of a third time constant to improve dynamic response and provision for the modelling of partitions and solid ground floors. The output from a simplified model incorporating these changes is compared with that for an established finite difference model and is found to be in close agreement for constructions and operating conditions typically found in the construction industry.
Separation of moisture flow through porous building materials into vapour and liquid components
Authors: Galbraith G.H. , Tao Z. , McLean R.C.
Published: December 2008

The prediction of the effects of moisture in buildings is now a well-established part of the building design process. A significant international effort is taking place to develop combined heat and mass transfer models which will enable the thermal and hygric performance of building envelopes to be more accurately assessed. However, the universal solution of the defining equations requires the separation of the total moisture flow into its liquid and vapour components for any specified set of humidity conditions. Until now this has not been possible and partial model solutions have required the premise that liquid water flow in porous building materials only becomes significant at humidities approaching 100%. Such an assumption is simplistic and clearly at variance with the body of experimental evidence. This paper presents an analytical and experimental procedure which allows the transport parameters defining liquid and vapour flow to be described for any given material as functions of relative humidity. Such information allows for a complete model solution without recourse to questionable assumptions regarding the initiation of capillary condensation.
Perceived air quality: Discussion on the new units
Authors: Oseland N.A. , Raw G.J.
Published: December 2008

The new units of perceived air quality, the olf and the decipol, are introduced and a brief description is given of how the units were derived. The units are based on odour and irritation acceptability. Research using these units has been used to argue that current recommended ventilation rates are inadequate for comfort. However, rather than increasing ventilation rates to obtain comfort, it is recommended that buildings be made from non-odorous and non-irritating, materials. The validity of using the new air quality units to determine ventilation rates and to compare pollutant emission rates between sources is evaluated in relation to the derivation of the method and the practical limits on its application.
Thermal radiation in a room : Numerical evaluation
Authors: Malalasekera W M G , James E.H.
Published: December 2008

This paper describes the use of the discrete transfer method for the calculation of radiative heat transfer in heated situations within buildings. The principal features and the flexibility of the method are illustrated by considering a number of representative thermal conditions found in room configurations. Results obtained by the discrete transfer method are compared with the results from the standard matrix method. The study also demonstrates how the discrete transfer method is capable of evaluating the distribution of heat fluxes on wall surfaces in complex geometrical situations. Its use has a clear advantage in situations where the standard methods require considerable user input.
Simulation of room flows with small ventilation openings by a local grid-refinement technique
Authors: Li Y. , Holmberg S. , Paprocki A. , Tang Y-Q.
Published: December 2008

Small ventilation openings in large rooms constitute a numerical resolution difficulty in indoor air flow simulation. A local grid-refinement technique is introduced to add local grid points in the small-opening regions. The method requires a relatively small increase in computer storage. A multi-grid algorithm, which turns out to be an efficient and accurate solves is used to solve the discrete system of equations on both global and local grids. A method for implementing the wall function in the solution procedure is described. Solutions of a three-dimensional isothermal mixing ventilation problem at Reynolds number of 5000 are compared with the experimental results in the literature. The method is then applied in a three-dimensional scaled model room ventilated by a plaque diffuser. The calculations show good agreement with the smoke visualisations of the flow pattern close to the diffuser. The method can be used to predict air flows with more realistic ventilation openings and more applications in large enclosures are expected in the future.
Heating consumption measurement in electrically heated dwellings
Authors: Hayton J.
Published: December 2008

Comparisons between energy consumptions of dwellings heated by different fuels are often hampered by the lack of published, practical data. This paper provides an analysis of electric space heating measurements from a project carried out by the Building Services Research and Information Association (BSRIA), and from a separate study by the Building Research Energy Conservation Support Unit (BRECSU) funded by the Energy Efficiency Office. The analysis is based on data from 24 dwellings located in Scotland and Southern England from the BSRIA study and 17 dwellings located in the West Midlands from the BRECSU study. Heating systems comprised a mixture of storage and direct heaters. The consumption of on-peak and off-peak electricity was recorded on a fortnightly basis for a period of a year or more. Despite differences in tenure and system design, the results of the two studies are consistent. Based on these results the following conclusions can be drawn: the amount of electricity consumed at off-peak rates is primarily determined by the size and number of storage heaters installed and not by the design heat loss; for dwellings having electric storage heaters with charge capacities within 90-150% of the value recommended in the DOM 8 design guidelines, the percentage of electricity used at off-peak rates is at most 86%, and may be as low as 79% (taking the use of supplementary portable electric heaters into account); for dwellings which have heater capacities of 90% or less of the recommended values the average off-peak percentage is only between 49% and 69%; the measured electrical consumptions are consistent with levels expected for partial dwelling heating (e.g. when some rooms are heated for much less than nine hours a day). This suggests the proportion of consumption at off-peak rates for space heating established from this analysis are only appropriate for partial dwelling heating. The proportion of off-peak electricity required for whole dwelling heating is likely to be lower.
Fuzzy air handling system controller
Authors: So A T P , Chow T.T. , Chan W.L. , Tse W.L.
Published: December 2008

Modem air conditioning systems for commercial buildings commonly employ the concept of a 'central all-air system' and the variable air volume (VAV) system in particular is widely used in Hong Kong and elsewhere other places around the world for energy conservation. In the lengthy wet summer season of Hong Kong, centralised air handling units (AHUs) dehumidify and cool down the appropriate mixture of return air and outdoor fresh air to feed a ducting network to various VAV boxes. A good controller for the AHUs is extremely desirable from both human comfort and energy saving points of view. In this paper, a simulation model for a practical air handling system is presented. Its behaviour under a conventional system of PID controllers is studied. A new controller based on fuzzy logic has been developed where all the parameters including input variables and actuating variables are represented as fuzzy subsets with carefully assigned membership functions. Such a controller is expected to directly replace the conventional PID controllers with identical input and output points. Based on an expert system developed from the recommendations of experienced human operators on air conditioning control, decision rules for proper control actions are laid down. Computer simulation as detailed in this paper has proved that such a fuzzy logic-based controller is superior to a conventional, cvell-tuned PID controller in at least three aspects. Fuzzy logic-based control is more robust since slight changes in the values of parameters do not greatly affect the performance compared with detuned PID control. The response rate of fuzzy logic-based control is faster when there is a sudden change in the environment. Energy saving is another merit of using fuzzy logic-based control.
Airflow in ducts: Measurement by perfluorocarbon (PFT) tracer
Authors: Cheong K.W. , Riffat S.B.
Published: December 2008

This paper describes the development of a tracer-gas system for measuring airflow in ducts, The fast-response system is capable of sampling different types of gases including a perfluorocarbon tracer (PFT) which was used for this siudy. The PFT, which is a liquid at room temperature, was injected into the duct using a thermostatically controlled heating block Tracer gas samples were collected using stainless steel tubes packed with adsorbent. The samples were stored for subsequent analysis in the laboratory using a thermal desorber and gas monitor. Airflow in duels was tested in the laboratory and field using the sampling and injection units.
Building control systems: Evaluation of performance using an emulator
Authors: Dexter A.L. , Haves P.
Published: December 2008

The control performance of an air-conditioning system is assessed using a qualitative method of evaluation. Fuzzy logic is used to relate performance criteria expressed in the form of IF-THEN rules to quantitative measures of energy consumption, discomfort, and maintenance costs. Test data were generated using an emulator consisting of a real-time simulation of the building shell and HVAC plant, together with a hardware interface that connects the simulation to commercial control equipment. Two case studies are presented. In the first, the effect of changing the strategy used to determine the zone temperature set-points is evaluated using 'expert rules', generated by a hypothetical facilities manager. In the second case study, the effect of varying the tuning parameters of the control system is evaluated using two sets of rules assumed to represent the differing perspectives of a facilities manager and a control engineer.
Effect of ventilation rate on deposition of aerosol particles on materials
Authors: Adam N.M. , Kohal J.S. , Riffat S.B.
Published: December 2008

This Note describes measurements carried out in a single-zone chamber using aerosol particles and tracer gases. Aerosol particles and a tracer gas were injected into the chamber and their concentrations with time were monitored. The rate of deposition of particles on the surfaces of the chamber was determined for a range of ventilation rates. The chamber was lined with various types of materials, e.g. aluminium foil, carpet and the deposition rate of particles of different sizes was examined. Results indicated that particle exchange rates were higher than tracer gas exchange rates. This was due to the deposition of particles on surfaces of the chamber. The deposition rate was found to depend on the type of lining material and size of particles used.
The adaptive model of thermal comfort: Patterns of correlation
Authors: Davies A D M , Davies M.G.
Published: December 2008

gummary The reactions of children in a school classroom were noted at weekly intervals over a period including summer, autumn, spring and summer. To achieve thermal comfort they could adjust the number of items of clothing they wore, they could open windows to cool the room and switch lights on to warm it. These means of moderating the environment show relatively high correlation with the quantity to which adaptation was being made — temperature — and low correlation with the state to be achieved - thermal neutrality. These correlations can be arranged so as to demonstrate causal, co-variational and feedback relationships.
Frequency-inverter controlled pumps as a cause of pipeline resonance
Authors: Dunn A. , Keung Lai Chi
Published: December 2008

Pumping systems using frequency inverters to achieve variable speed control have often been reported to become unstable under certain operating conditions. An experimental study has shown that harmonics present in the output current of a frequency inverter give rise to corresponding pressure harmonics at the discharge of the pump. Moreover, certain harmonics can occur at frequencies low enough actively to excite the piping system and give rise to resonance.