Design of a Third-party Reverse Logistics Network under a Carbon Tax Scheme

© 2016 Eastern Macedonia and Thrace Institute of Technology. Reverse logistics network involves significant inherent uncertainties, which cannot be completely characterized because of a lack of adequate historical data. In this study, a multi-product and multi-period interval programming model was developed on the basis of partial information to design an effective reverse logistics network. In addition, the trade-offbetween economic benefits and the environmental burdens from carbon emissions was analyzed by considering the effect of a carbon tax scheme on the reverse logistics network design. Through an improved and modified interval linear programming method, the optimal interval solution was obtained with LINGO. Finally, numerical simulations were conducted to explore the effectiveness of the model and the effect of the carbon tax scheme. Results show that the optimal solution of the reverse logistics network design is robust. The effect of the carbon tax scheme is trivial when the carbon tax is low and significant when the carbon tax is high. As carbon tax gradually increases, carbon emissions effectively decrease, but sharply declines the total profit sharply declines. The findings indicate that the proposed model can effectively solve the reverse logistics network design with partial information under a carbon tax scheme

Epidemiology of acute primary angle-closure glaucoma in the Hong Kong Chinese population: prospective study.

OBJECTIVES: To determine the incidence of acute primary angle-closure glaucoma in the Hong Kong Chinese population, and to identify risk factors for this condition. DESIGN: Prospective study. SETTING: University teaching hospital, Hong Kong. PARTICIPANTS: Patients with acute primary angle-closure glaucoma presenting between 1 March 1998 and 29 February 2000. MAIN OUTCOME MEASURES: Demographic data, presenting symptoms and signs, temporal details of the presentation, and precipitating factors. The crude regional incidence was calculated according to the Hong Kong population census of 1991 and the age-specific incidence was calculated. RESULTS: Seventy-two cases (72 eyes of 72 patients) of acute primary angle-closure glaucoma were recruited. The crude incidence was 10.4 per 100,000 per year in the population aged 30 years and older. Patients at higher risk of attacks were those aged 70 years or older (age-specific incidence, 58.7 per 100,000 per year) and females, who had a relative risk of 3.8 compared with males (95% confidence interval, 1.7-8.4). Only four (5.6%) patients had a positive family history of acute primary angle-closure glaucoma. Seventeen (23.6%) patients were noted to have an upper respiratory tract infection before the attack, and 25 (34.7%) patients had taken antitussive agents. There was a statistically significant inverse correlation between the monthly attack rate and the monthly rate of influenza (Spearman's rank correlation coefficient = -0.388; P=0.031). CONCLUSION: There is a high incidence of acute primary angle-closure glaucoma among Chinese residents of Hong Kong, with elderly females at highest risk. A significant proportion of patients reported upper respiratory tract infection or the use of antitussive medication prior to attacks.published_or_final_versio

从学术典藏库(IR)到当前科研信息系统(CRIS) - 如何和为何

published_or_final_versio

The HKU Scholars Hub - Beyond an institutional repository

香港大學學術庫是香港大學的機構知識庫,是響應大學知識交流政策而建立的知識管理系統。憑藉豐富的資料來源以及合理的設計機制,學術庫已成為頗具影響力的香港大學人才和科研成果的展示平臺,成為校內外學術交流的中心,為學術評估和聲譽管理提供了基礎。The HKU Scholars Hub (The Hub), the institutional repository of The University of Hong Kong (HKU), is a knowledge system in answer to the University’s knowledge exchange initiative. Benefiting from extensive data loads internal and external to HKU and the design mechanism, The Hub becomes a highly visible online expertise directory collectively showing HKU’s talents and research works, and provides tools for the University and the scholars to do research assessment and reputation management.postprin

Algorithms for Colourful Simplicial Depth and Medians in the Plane

The colourful simplicial depth of a point x in the plane relative to a configuration of n points in k colour classes is exactly the number of closed simplices (triangles) with vertices from 3 different colour classes that contain x in their convex hull. We consider the problems of efficiently computing the colourful simplicial depth of a point x, and of finding a point, called a median, that maximizes colourful simplicial depth. For computing the colourful simplicial depth of x, our algorithm runs in time O(n log(n) + k n) in general, and O(kn) if the points are sorted around x. For finding the colourful median, we get a time of O(n^4). For comparison, the running times of the best known algorithm for the monochrome version of these problems are O(n log(n)) in general, improving to O(n) if the points are sorted around x for monochrome depth, and O(n^4) for finding a monochrome median.Comment: 17 pages, 8 figure

Beyond bibliographic metadata, augmenting the HKU IR

The HKU Scholars Hub (The Hub) is the institutional repository of the University of Hong Kong (HKU), which from 2005 has placed items in open access. However in 2009, a new university initiative appeared, Knowledge Exchange, which recognizes the 3rd mission of universities, to engage with their communities, for bilateral benefit. In this regard The Hub received funding from the HKU Office of Knowledge Exchange, to make HKU research and researchers highly visible, in the expectation that this will greatly increase opportunities for contract and collaborative research, the creation of cross-institutional multidisciplinary teams for e-research, etc. To answer this need, The Hub hosted in DSpace, needed to quickly augment existing bibliographic metadata, add metadata on other objects, such as people, grants, patents, etc., and augment this metadata as well. Bibliographic Metadata: We receive a data feed of publication metadata from the HKU Research Output System (ROS) database, managed by the HKU Registry. This metadata is usually dirty and thin. To ameliorate we created several procedures: 1) A web service on ROS, to receive a DOI or ISBN, and then auto-populate the record with data from CrossRef or OCLC, without any other input from the user. Our next planned step, is to refuse entry into ROS, without a DOI or ISBN in most cases. 2) Thin metadata from ROS, and even data from CrossRef or OCLC, can be augmented, or further cleansed, to add more value, and of course more access points for search engine optimization. We have had an on-going project for several years to clean HKU metadata in Scopus. Therefore the Scopus AU-IDs for HKU people are “mostly” correct. We now use the Scopus API, matching on corresponding AU-IDs, to bring back publisher supplied metadata on HKU publications. After giving HKU authors one last time to deny ownership to this metadata, we overlay our existing thin and dirty metadata with full and correct metadata. 3) To show publication metadata authored previous to authors’ HKU tenure, we retrieve RIS or XML data from Scopus, or from author supplied EndNote files. 4) With correct DOI, we can bring in on-the-fly, corresponding citation counts from Scopus, Web of Science, PubMed Central, etc. Author Metadata: We created ResearcherPages for each of the approximately 1,400 scholars, eligible to apply for grant funding. These pages show their publication lists linked to fulltext, or remotely subscribed fulltext. However, we soon found that some disciplines do not value publications as indications of scholarly worth. For these we added other types of metadata, such as Awards, which greatly pleased the Faculty of Architecture, and those receiving teaching awards. Other facets that we added were, HKU Committees, Supervision of Graduate Students, Grants, Bibliometrics, etc. Thesis Metadata: HKU has three separate, and separately controlled silos for thesis metadata and fulltext objects, each with issues of dirty or thin metadata: a) Graduate School, b) Student Information Service (Registry), and c) library catalogue records. The first two of these are dark databases, allowing no public access. We have had to create processes to update each silo with supplementary data from the others. For The Hub, this means that we can now show for each supervisor, complete lists of supervised students, with a correct thesis title hyperlinked to the fulltext thesis, also in The Hub. At the other end of the hyperlink, the record for a thesis will now show a link to a supervisor. We have become a publisher in CrossRef, and are issuing DOI numbers to each HKU thesis. This will make them more visible, and eventually allow us to show citation counts beside each thesis. Grant Metadata: We import this metadata from a dark database controlled by the Registry. It is now publicly accessible in the Hub showing hyperlinks to the ResearcherPages of PI and Co-I, as well as to grants of similar sponsor, panel, etc. Recently we found ways to hyperlink from the Grant record, to a publication resulting from that grant. Patent Metadata: We receive metadata from the HKU Technology Transfer Office, which is limited and focused upon patents in the US. We have built VBnet scripts to use the patent publication or issued number, search on the patent offices of the US, China, EU, Japan and others to bring back complete metadata, which includes priority dates, patent numbers of application, continuation, and of corresponding patents by the same HKU inventors in other jurisdictions, aka., “patent family”. We then use these newly received numbers to retrieve metadata for their complete records and display in The Hub. In the end, we have patent records that show a complete history from application to issuance and hyperlinkage to patents in the same family. All of this increased metadata, which is augmented, and becoming cleaner, has increased the utility of the Hub, and enabled content re-use: 1) We can now show hyperlinked visualizations of networked people, based upon co-authorship, co-investigatorship, same committee, same keyword in publication, patent, research interest, etc. 2) We provide a web service for the HKU departments to extract from The Hub metadata and build author profiles in their departmental pages. 3) Some HKU offices, realizing that we can present better data and attract more eyes, have asked us to take-over services that they once provided. 4) We can send files of augmented and clean metadata back to our original data providers, thus allowing their records to benefit from our work. 5) We use Thomson Reuter provided API to auto-create and auto-populate the TR ResearcherID for each of our 1,400 authors. Each Hub record on people, publication, grant, and patent will show download and view counts. These internal measures, anecdotes, and external measures, such as the Webometrics “Ranking Web of World Repositories” indicate that we have succeeded in making visible the research and researchers of HKU.published_or_final_versio

The efficacy of a lateral wedge insole for painful medial knee osteoarthritis after prescreening : a randomized clinical trial

OBJECTIVE: Lateral wedge shoe insoles decrease medial knee loading, but trials have shown no effect on pain in medial knee osteoarthritis (OA). However, insoles' loading effects are inconsistent, and they can increase patellofemoral loading. We hypothesized that insoles would reduce pain in preselected patients. METHODS: In persons with painful medial knee OA, we excluded those with patellofemoral OA and those with pain <4/10. We further excluded participants who, in a gait laboratory using lateral wedges, did not show at least a 2% reduction in knee adduction moment (KAM) compared with their shoes and a neutral insole. We then randomized subjects to lateral wedge vs. neutral insole for 8 week periods separated by an 8 week washout. Primary outcome was knee pain over the past week (0-10) and secondary outcomes nominated activity pain and KOOS pain. We carried out mixed model analyses adjusted for baseline pain. RESULTS: Of 83 participants, 21 (25%) were excluded because of insufficient reduction in KAM. Of 62 included, mean age was 64.2 years (SD 9.1); 37.1% were women. Lateral wedge insoles produced a greater reduction in knee pain than neutral insoles (difference 0.7 on 0-10 scale; 95%CI 0.1, 1.2; p = 0.02). Secondary outcomes showed mixed findings. CONCLUSIONS: In persons prescreened to eliminate those with patellofemoral OA and biomechanical non-responders, lateral wedge insoles reduced knee pain, but the effect of treatment was small and is likely of clinical significance in only a minority of patients. Targeting patients may identify those who respond to this treatment

Barley plasma membrane intrinsic proteins (PIP aquaporins) as water and CO2 transporters

We identified barley aquaporins and demonstrated that one, HvPIP2;1, transports water and CO2. Regarding water homeostasis in plants, regulations of aquaporin expression were observed in many plants under several environmental stresses. Under salt stress, a number of plasma membrane-type aquaporins were down-regulated, which can prevent continuous dehydration resulting in cell death. The leaves of transgenic rice plants that expressed the largest amount of HvPIP2;1 showed a 40% increase in internal CO2 conductance compared with leaves of wild-type rice plants. The rate of CO2 assimilation also increased in the transgenic plants. The goal of our plant aquaporin research is to determine the key aquaporin species responsible for water and CO2 transport, and to improve plant water relations, stress tolerance, CO2 uptake or assimilation, and plant productivity via molecular breeding of aquaporins.</p

The momentum analyticity of two-point correlators from perturbation theory and AdS/CFT

The momentum plane analyticity of two point function of a relativistic thermal field theory at zero chemical potential is explored. A general principle regarding the location of the singularities is extracted. In the case of the N=4 supersymmetric Yang-Mills theory at large $N_c$, a qualitative change in the nature of the singularity (branch points versus simple poles) from the weak coupling regime to the strong coupling regime is observed with the aid of the AdS/CFT correspondence.Comment: 18 pages, 3 figures, typos fixed, 1 figure update

Refractive index in holographic superconductors

With the probe limit, we investigate the behavior of the electric permittivity and effective magnetic permeability and related optical properties in the s-wave holographic superconductors. In particular, our result shows that unlike the strong coupled systems which admit a gravity dual of charged black holes in the bulk, the electric permittivity and effective magnetic permeability are unable to conspire to bring about the negative Depine-Lakhtakia index at low frequencies, which implies that the negative phase velocity does not appear in the holographic superconductors under such a situation.Comment: JHEP style, 1+15 pages, 11 figures, version to appear in JHE