8,027 research outputs found

    Sequential item pricing for unlimited supply

    Get PDF
    We investigate the extent to which price updates can increase the revenue of a seller with little prior information on demand. We study prior-free revenue maximization for a seller with unlimited supply of n item types facing m myopic buyers present for k < log n days. For the static (k = 1) case, Balcan et al. [2] show that one random item price (the same on each item) yields revenue within a \Theta(log m + log n) factor of optimum and this factor is tight. We define the hereditary maximizers property of buyer valuations (satisfied by any multi-unit or gross substitutes valuation) that is sufficient for a significant improvement of the approximation factor in the dynamic (k > 1) setting. Our main result is a non-increasing, randomized, schedule of k equal item prices with expected revenue within a O((log m + log n) / k) factor of optimum for private valuations with hereditary maximizers. This factor is almost tight: we show that any pricing scheme over k days has a revenue approximation factor of at least (log m + log n) / (3k). We obtain analogous matching lower and upper bounds of \Theta((log n) / k) if all valuations have the same maximum. We expect our upper bound technique to be of broader interest; for example, it can significantly improve the result of Akhlaghpour et al. [1]. We also initiate the study of revenue maximization given allocative externalities (i.e. influences) between buyers with combinatorial valuations. We provide a rather general model of positive influence of others' ownership of items on a buyer's valuation. For affine, submodular externalities and valuations with hereditary maximizers we present an influence-and-exploit (Hartline et al. [13]) marketing strategy based on our algorithm for private valuations. This strategy preserves our approximation factor, despite an affine increase (due to externalities) in the optimum revenue.Comment: 18 pages, 1 figur

    Dynamic Voltage Scaling Techniques for Energy Efficient Synchronized Sensor Network Design

    Get PDF
    Building energy-efficient systems is one of the principal challenges in wireless sensor networks. Dynamic voltage scaling (DVS), a technique to reduce energy consumption by varying the CPU frequency on the fly, has been widely used in other settings to accomplish this goal. In this paper, we show that changing the CPU frequency can affect timekeeping functionality of some sensor platforms. This phenomenon can cause an unacceptable loss of time synchronization in networks that require tight synchrony over extended periods, thus preventing all existing DVS techniques from being applied. We present a method for reducing energy consumption in sensor networks via DVS, while minimizing the impact of CPU frequency switching on time synchronization. The system is implemented and evaluated on a network of 11 Imote2 sensors mounted on a truss bridge and running a high-fidelity continuous structural health monitoring application. Experimental measurements confirm that the algorithm significantly reduces network energy consumption over the same network that does not use DVS, while requiring significantly fewer re-synchronization actions than a classic DVS algorithm.unpublishedis peer reviewe

    Home Bound Working Women and Organizational Efficiency of Developing Economy

    Get PDF
    This research aims to understand the preferences of educated unemployed womenof Pakistan and India on the imposition of the law of “Flex time/rules for homebound educated women”. For this purpose, 158 respondents were asked to f illa survey out of which 79 respondents were educated employed women and 79respondents were unemployed women (79). Chi-square was applied to the data.Findings suggest that 94% of the women from both the groups are of the viewthat an introduction of women quota would result in an increase in women par-ticipation in the workforce. To understand management’s perspective, 6 inter-views with HR heads of selective industries were conducted. Narrative Analysiswas applied which revealed only 10 to 20% women participated in the totalworkforce. The study also highlights reasons for low women participation. Theseinclude cultural norms, maternal issues, maternity problems, after marriage re-strictions and childbirth. The study concludes that introducing an introductionof women quota in both public and private sectors would help increase womenparticipation and contribution to the country’s economy

    Antipsychotic medication side effects knowledge amongst registered mental health nurses in England: A national survey

    Get PDF
    © 2020 The Authors. Journal of Psychiatric and Mental Health Nursing published by John Wiley & Sons Ltd What is known on the subject?: Research findings indicate the percentage of knowledge-related errors in medicines management is high, accounting for approximately 75% of all errors, with insufficient knowledge levels one of the most significant contributors of medication errors. Patients should be able to trust nurses to engage therapeutically and actively listen to their needs and concerns, responding using skills that are helpful, providing information that is clear, accurate, meaningful and free from jargon. However, without knowledge of pharmacology, it is impossible for nurses to be able to provide adequate advice. What the paper adds to the existing knowledge?: This study has examined an area that had not yet been systematically examined previously, which draws together previous research findings on mental health nurses' knowledge of adverse events, including side effects and medication errors, related to antipsychotic medication within NHS inpatient settings. What are the implications for practice?: A recent study has found that almost three-quarters (73%) of patients taking antipsychotic medication reported side effects to some degree. This high number of people experiencing antipsychotic medication side effects is likely to compromise care, especially in situations where nurses have inadequate knowledge of side effects and are unable to provide effective advice to patients. The findings from this study allow the mental health nursing profession an opportunity to reflect on the best means to increase knowledge and increase patient safety awareness and benefits for mental health service users. Abstract: Introduction Antipsychotic medications play a significant role in the treatment and recovery of people with several psychiatric disorders. However, research findings indicate mental health nurses are insufficiently knowledgeable about antipsychotic medication side effects. Aim To assess practising mental health nurses' knowledge of antipsychotic medication side effects using a Multiple-Choice Questionnaire (MCQ) across National Health Service (NHS) Trusts in England. Hypothesis Knowledge of antipsychotic medication side effects amongst registered mental health nurses is related to their academic qualification, clinical banding and length of experience. Method A national survey of registered mental health nurses was carried out using an online questionnaire which was disseminated by Research and Development departments. Results A total of 504 questionnaires were returned, 245 of which had full data and further analysed. The mean score for the sample was 14.4 and only 21 participants attained a mark of >80%. Implications for Practice Two out of three of our hypotheses (that length of experience and clinical banding are directly related to knowledge of antipsychotic medication side effects) were supported. Our study found many nurses have a suboptimal working knowledge of antipsychotic medication side effects which has the potential to compromise care. Strategies need to be put in place to enhance pharmacology knowledge

    Cognitive Style as a Factor in Accounting Students\u27 Performance on Multiple Choice Examinations

    Get PDF
    Using 59 final year accounting students as subjects and multiple regression analysis, this paper tests the hypothesis that accounting students\u27 performance on multiple choice examinations is related to field dependence cognitive style. Results support the hypothesis and suggest that in evaluating student performances in multiple choice examinations, accounting academics should bear in mind that the scores on these examinations may be partly a function of students\u27 cognitive style. This finding has implications for the use of multiple choice examinations in classroom evaluations

    The effects of different growing media on flowering and corm formation of saffron (Crocus sativus L.)

    Get PDF
    The objective of this research was to determine the effects of different growing media on saffron growth and corm formation in greenhouse conditions. In the experiment four different treatments were used.These were (1) soil+sand (control), (2) soil+sand+manure, (3) soil+sand+manure applied as a double layer above and bottom of corm bed, and (4) soil+sand+manure+ nitfojips-K. The results revealed thateffects of the growing media on most of the characters were significant. Cow manure mixtures especially with double layers had a positive effect on the flower and stigma weight. Average flower weight per plant change between 0.157 - 0.240 g. The corm size did not change significantly intreatments 1, 2 and 3. However, in treatment 4, both corm weight and corm size were significantly lower than they were in the other treatments. The results suggested that the growing medium was one of the important factors for saffron flower and corm formation

    Primary Splenic Hydatid: A Case Report

    Get PDF
    Hydatid disease is a parasitic infection caused mainly by Echinococcus granulosus and is a common entity in this part of the world . However, primary hydatid disease of spleen is a rare entity. We are reporting a case of a massive primary splenic hydatid cyst in a 27 yr old female, who presented with left upper quadrant swelling and pain. USG disclosed a large hydatid cyst and the CT scan confirmed the diagnosis. IgM Elisa for hydatid serology was strongly positive. An elective open splenectomy was performed, with an uneventful post operative recovery
    • …
    corecore