A Smart Metering Scheme for a Smart Grid System

Fulltext at http://joa.csee.org.cn/Public/DownloadFile.aspx?FileStorageId=4ee2fb00-309e-44b8-ad54-63e076762d99The development of smart grid systems calls for new metering schemes in measuring consumption and power flow metrics between connected entities. The new meters which import the concept of renewable resource should also carry intelligence and communication compatibility for enhancement of new applications in demand side management. Our project explores network relationships of stakeholder parties in a smart grid system and their value channel behavior. A potentially successful smart metering scheme must carry a win-win-win scenario that satisfies all the partners involved. It is important to understand possible network partnership behavior. The scheme must resolve the potential contradictions and induce a balance of interests. Continuing our earlier study on the smart metering schemes, a derivative business model and the interface platform are further discussed by this paper

A transverse flux permanent magnet linear generator for hybrid electric vehicles

Article: TD-007358This paper presents a transverse flux permanent magnet (TFPM) linear generator for the free-piston generation application, which not only possessing the merits of the existing TFPM machine, but also providing a simple structure which is essential for power generation with maintenance-free operation. Also, the machine configuration is optimized such that the induced voltage is maximized while the cogging force is minimized. Hence, a 2-phase linear TFPM is resulted, which is well supported by performance analysis.published_or_final_versio

Equal reverberance contours for synthetic room impulse responses listened to directly: Evaluation of reverberance in terms of loudness decay parameters

This paper examines effects of listening level and reverberation time on the perceived decay rate of synthetic room impulse responses (RIRs). A listening test was conducted with synthetic RIRs having a range of listening levels and reverberation times: in the test, subjects adjusted a physical decay rate of the RIRs to match the perceived decay rate of reference stimuli. In this way, we constructed equal reverberance contours as a function of sound pressure level and reverberation time. The experiment results confirm that listening level and reverberation time both significantly affect reverberance. The study also supports our previous finding: that the loudness decay function can be used to predict reverberance better than the conventional reverberance predictors

Ambulatory stapled haemorrhoidectomy: A safe and feasible surgical technique

Objective. To compare outcomes following stapled haemorrhoidectomy as an in-patient versus day-surgery procedure. Design. Prospective non-randomised study. Setting. University affiliated hospitals, Hong Kong. Subjects and methods. Forty-eight consecutive patients who underwent stapled haemorrhoidectomy were included in the study. Twenty-four patients had the procedure in an ambulatory setting and the other 24 were treated as in-patients. The symptoms, operative details, postoperative complications, length of hospital stay, pain scores, analgesic requirements, and patient satisfaction scores were collected. Comparison was made between those patients undergoing ambulatory surgery and those treated as in-patients. Results. There were 25 women and 23 men in the study. The mean age was 46.6 years (standard deviation, 12.1 years). The mean operating time was 29.3 minutes (standard deviation, 9.9 minutes). An incomplete 'doughnut' after stapling was found in one patient. There were no other adverse intra-operative events or complications. Postoperative morbidities occurred in eight patients but none required further surgery. One patient in the day-surgery group could not be discharged because of urinary retention and three required re-admission to hospital because of secondary haemorrhage (n=1) or fever (n=2). There were no differences in the postoperative complications, pain scores, analgesic requirements, and patient satisfaction scores between the two groups. The total mean hospital stay was significantly shorter for those undergoing day-surgery stapled haemorrhoidectomy (0.46 versus 1.9 days, P<0.01). The mean follow-up period was 4.6 months (standard deviation, 4.0 months). All patients reported symptomatic improvement during this time and there was no incidence of faecal incontinence. One patient had a soft stricture, one had a fissure, and two had residual skin tags. All of these problems were conservatively managed, without the need for further surgical procedures. Conclusions. Stapled haemorrhoidectomy is a safe and effective operation for haemorrhoids. It is a feasible procedure to perform as day-surgery. The hospital stay can be significantly shortened, thus reducing the costs associated with in-patient care.published_or_final_versio

Efficacy of selective laser trabeculoplasty for normal tension glaucoma: 1 year results

BACKGROUND: Normal tension glaucoma (NTG) is commonly treated with anti-glaucoma medications. Recently, selective laser trabeculoplasty (SLT) has been demonstrated to lower the intraocular pressure (IOP) and medication use in NTG. The purpose of this study was to investigate the efficacy of a single session of SLT for NTG at 1 year. METHODS: This prospective cohort study recruited NTG patients taking anti-glaucoma medication. Potential subjects were excluded if they had had previous glaucoma surgery or laser and also if intraocular surgery or additional SLT procedures were performed after the first treatment. All subjects underwent a 1-month washout. A 30% IOP reduction was set as the target IOP. A single session of SLT was performed to 360 degrees of the trabecular meshwork. At 1-month after SLT, medication was resumed to achieve the target IOP. The IOP was measured every 3 months, and the number of medications was recorded at 3, 6, and 12 months. Only the right eye was used for statistical analysis. RESULTS: In 41 right eyes, the mean pre-study IOP was 14.3 +/- 3.4 mmHg while on 1.5 +/- 0.8 eye drops. The post-washout IOP was 16.2 +/- 2.2 mmHg. A mean of 191.1 +/- 26.3 SLT shots at 1.0 +/- 0.07 mJ were applied. There was significant IOP reduction at all time intervals following SLT when compared to the post-washout IOP (P < 0.0001). The number of medications was significantly reduced at all time intervals following SLT when compared to the pre-study level (P < 0.0001). At 12 months, the mean IOP was 12.2 +/- 2.2 mmHg while on 1.1 +/- 0.9 eye drops. CONCLUSIONS: A single session of SLT for NTG achieved an additional 15% IOP reduction while using 27% less medication at 1 year compared to pre-study levels.Trial registration: The Clinical Trials Register of the University of Hong Kong HKCTR1847The European Clinical Trials Database 2014-003305-15 (August 11, 2014) (https://eudract.ema.europa.eu/).published_or_final_versio

Costs and financial benefits of undertaking green building assessments : final report

Construction Industry Institute-Hong Kong Report, no. 15Other Versio

Intelligibility of reverberant speech with amplification: Limitation of speech intelligibility metrics, and a preliminary examination of an alternative approach

This study examines the effect of speech level on intelligibility in different reverberation condi- tions, and explores the potential of loudness-based reverberation parameters proposed by Lee et al. [J. Acoust. Soc. Am., 131(2), 1194-1205 (2012)] to explain the effect of speech level on intelligi- bility in various reverberation conditions. Listening experiments were performed with three speech levels (LAeq of 55 dB, 65 dB and 75 dB) and three reverberation conditions (T20 of 1.0 s, 1.9 s and 4.0 s), and subjects listened to speech stimuli through headphones. Collected subjective data were compared with two conventional speech intelligibility parameters (Speech Intelligibility In- dex and Speech Transmission Index) and two loudness-based reverberation parameters (EDTN and TN). Results reveal that the effect of speech level on intelligibility changes with a room’s re- verberation conditions, and that increased level results in reduced intelligibility in highly rever- berant conditions. EDTN and TN explain this finding better than do STI and SII, because they con- sider many psychoacoustic phenomena important for the modeling of the effect of speech level varying with reverberation

Recommending anchor points in structure-preserving hypertext document retrieval

Traditional WWW search engines index and recommend individual Web pages to assist users in locating relevant documents. Users are often overwhelmed by the large answer set recommended by the search engines. The logical starting point of the hyper-document is thus hidden among the large basket of matching pages. Users need to spend a lot of effort browsing through the pages to locate the starting point, a very time consuming process. This paper studies the anchor point indexing problem. The anchor points of a given user query is a small set of key pages from which the larger set of documents that are relevant to the query can be easily reached. The use of anchor points help solve the problems of huge answer set and low precision suffered by most search engines by considering the hyper-link structures of the relevant documents, and by providing a summary view of the result set.published_or_final_versio

An exploratory study on the social and genotypic clustering of HIV infection in men having sex with men

OBJECTIVE: To explore the clustering of HIV infected men having sex with men (MSM) using social network approach in conjunction with the phylogenetic relationship of the virus strains. DESIGN: An exploratory study incorporating social network and phylogenetic analysis. METHODS: Recently diagnosed HIV-infected MSM attending one major HIV specialist clinic in Hong Kong were recruited in the study involving the administration of a self-administered questionnaire on behaviours and partnership patterns using a Likert Scale, the results of which were assessed using social network analysis and in context of the phylogenetic analysis from sequencing the HIV-1 pol gene, as part of the clinical investigation for genotypic resistance. Clusters were defined using social and molecular methods. RESULTS: An 'Internet-centred' cluster and 'Sauna-centred' cluster could be delineated using correspondence analysis and network diagrams. The main distinguishing features of MSM in the 'Internet-centred' social cluster were: younger age, higher education level, and multiple partner types. Three genetic clusters could be identified in the phylogenetic tree, two of which associated with Internet use and one with sauna for sex partnership. There were partial overlaps between social and genetic clusters. Characteristically, the virus strains in sauna users were more disperse compared with the closely knit configuration of those using Internet. CONCLUSION: The principle of the duality of place and person can be strategically applied in epidemiologic investigation. The characterization of MSM cluster using anonymized network data provides a potentially powerful tool for informing public health intervention. © 2009 Lippincott Williams & Wilkins, Inc.postprin

An analytic approximation to the Diffusion Coefficient for the periodic Lorentz Gas

An approximate stochastic model for the topological dynamics of the periodic triangular Lorentz gas is constructed. The model, together with an extremum principle, is used to find a closed form approximation to the diffusion coefficient as a function of the lattice spacing. This approximation is superior to the popular Machta and Zwanzig result and agrees well with a range of numerical estimates.Comment: 13 pages, 4 figure