842 research outputs found

    Motion Planning for Autonomous Ground Vehicles Using Artificial Potential Fields: A Review

    Full text link
    Autonomous ground vehicle systems have found extensive potential and practical applications in the modern world. The development of an autonomous ground vehicle poses a significant challenge, particularly in identifying the best path plan, based on defined performance metrics such as safety margin, shortest time, and energy consumption. Various techniques for motion planning have been proposed by researchers, one of which is the use of artificial potential fields. Several authors in the past two decades have proposed various modified versions of the artificial potential field algorithms. The variations of the traditional APF approach have given an answer to prior shortcomings. This gives potential rise to a strategic survey on the improved versions of this algorithm. This study presents a review of motion planning for autonomous ground vehicles using artificial potential fields. Each article is evaluated based on criteria that involve the environment type, which may be either static or dynamic, the evaluation scenario, which may be real-time or simulated, and the method used for improving the search performance of the algorithm. All the customized designs of planning models are analyzed and evaluated. At the end, the results of the review are discussed, and future works are proposed

    Molecular characterization of Pakistani wheat cultivars using random markers

    Get PDF
    The genetic diversity among fifteen varieties of wheat was studied by random amplified polymorphic DNA  (RAPD) analysis. By applying 20 RAPD primers, 182 fragments were amplified, out of which 118 were  polymorphic (64.84%). The number of fragments amplified per primer ranged from 10 to 24 with an average of  17 fragments per primer. Primer K-17 produced the maximum number of fragments (24) and all the fragments  were polymorphic. Range of polymorphism percentage was from as low as 0% (I to 15) to as high as 100%  (K-11). The number of fragments produced per wheat genotype varied from 36 to 56 with an average of 47.2  fragments per genotype. The variety Shahkar-95 produced maximum number of fragments (56). Cluster  analysis classified fifteen varieties of wheat into two main groups; three varieties were placed in group I and  the rest of the varieties were placed in group II. Second group (group II) was further divided into three  subgroups; IIA, IIB and IIC. The pair wise similarity values ranged from 54.88 to 82.93% and showed that  genotypes Kohinoor-83 and Pak-81 were the closest with highest similarity value (82.93%), while genotypes Kohinoor-83 and Kohistan-97 were most distinct with minimum similarity value (54.88%).Key words: Cultivar, polymorphism, random amplification of polymorphic deoxyribonucleic acid (RAPD), cluster analysis, genotype

    Effect of carbofuran on the diversity and mean abundance of ground spiders

    Get PDF
    The effect of carbofuran on the diversity, richness, evenness and abundance of ground spiders is documented in the present study. Two fields (control and treated) were selected in district Kasur during 2008 and 2009. Pitfall traps were used to collect ground spiders. A total of 1629 specimens of spiders, belonging to 8 families, 16 genera and 24 species were recoded from control field while 1173 specimens belonging to 8 families, 14 genera and 20 species were recorded from the treated field. The most dominant family and species in both the fields were Lycosidae and Lycosa terrestris, respectively. Family Lycosidae accounted more than 90% of the total spider sample. Diversity, richness and evenness of ground spiders in the treated and untreated field did not differ. However, the abundance of dominat spiders declined significantly in the carbofuran treated field. It is concluded that the use of carbofuran is a serious threat to the ground spiders, the important group of biological control agents. So, the use of carbofuran should be minimized in the fields.Key words: Ground spiders, carbofuran, natural predators, pest reduction

    Adversarial Stacked Auto-Encoders for Fair Representation Learning

    Get PDF
    Training machine learning models with the only accuracy as a final goal may promote prejudices and discriminatory behaviors embedded in the data. One solution is to learn latent representations that fulfill specific fairness metrics. Different types of learning methods are employed to map data into the fair representational space. The main purpose is to learn a latent representation of data that scores well on a fairness metric while maintaining the usability for the downstream task. In this paper, we propose a new fair representation learning approach that leverages different levels of representation of data to tighten the fairness bounds of the learned representation. Our results show that stacking different auto-encoders and enforcing fairness at different latent spaces result in an improvement of fairness compared to other existing approaches.Comment: ICML2021 ML4data Workshop Pape

    Adoption of JMM practices – A key to performance improvement of a local automotive industry

    Get PDF
    It is imperative for a manufacturing company all over the world to constantly look for ways to increase productivity and at the same time to lower cost to secure a competitive position. It is recognized that practices associated with Japanese Manufacturing Management (JMM) can yield a superior competitive advantage in terms of productivity, quality and provide overall successful business performance. This paper discusses the transfer of the best practices of the JMM locally and analyses the impact of adoption and adaptation of the management system as an in-depth case study conducted in a Malaysian automotive company. This study is to identify what are the changes in terms of the philosophy and practices undertaken by the company and ascertain the impact of the JMM on its manufacturing and financial performances. The elements of business performance from the viewpoint of manufacturing are based on safety, Parts Per Million (PPM), in-line Defect per Unit (DPU), First Time Quality (FTQ), cycle time, productivity, efficiency and stock level. The results show a positive impact to the automotive plant manufacturing performance. For example, safety index has reduced to 0 major accident occurrences. The PPM and In-line DPU have improved by 98% and 91% respectively whereas the FTQ has improved by 167%. Cycle time has reduced from 20 to 6 minutes and productivity increased up to 43% whilst the efficiency reached at 99.9%. The stock level was reduced from half month to 3 days after the adoption of the JMM. The revenue has increased up to 92%, the percentage of expenses has reduced from 11.04% to 3.06% giving an improvement of 72% whilst the net profit has increased from 5.33% to 8.15%. The Return of Asset (RoA) and Return of Equity (RoE) also showed slight improvement despite the effects from the restructuring exercise, Tsunami calamity and fluctuation in Japanese exchange rate

    Perceptions and Attitudes of Medical Sales Representatives (MSRs) and Prescribers Regarding Pharmaceutical Sales Promotion and Prescribing Practices in Pakistan

    Get PDF
    Pakistan is the 6th most populous country in the world and has an enormous potential for an ever increasing drug market. The health care system is highly prone to unethical drug prescribing practices. In addition, there is a huge tendency of pharmaceutical firms to indulge in unethical drug promotional practices by means of inducements and other benefits through their medical sales representatives (MSRs). On the other hand, the prescribers are also reported to be demanding inducements from these companies in return to write higher number of prescription. This study investigated the ground realities of drug promotion and prescribing practices in Pakistan. Materials and Methods: A cross sectional study was conducted for a period of 8 months in which 472 physicians and 609 medical sales representatives of Pakistan selected through prospective sampling were interviewed on a validated, structured questionnaire. The responses of the target groups were then analyzed for association between variables by Chi–square test (p<0.05) and cross tabulation through SPSS, version 20. Results: Majority of practitioners (83.2%) expected both, good communication skills and knowledge from MSRs and at the same time nearly half (53%) of prescribers demanded CME and almost a third proportion (36%) demanded gifts, incentives and inducements from MSRs. Replying to same question, MSRs disagreed with prescribers and believed that around (~70%) of prescribers ask for inducements with a high percentage i.e. (~64%) among them demanding unethical inducements like excessive free samples, gifts, leisure trips and cars. Majority of physicians (92%) have consensus that the multinational pharmaceutical firms have defined promotional practices while the national pharmaceutical companies (~73%) are mainly involved in unethical practices of drug marketing. Conclusion: Majority of national pharmaceuticals as well as prescribers were involved in unethical drug promotion and prescribing respectively. There is a need of curbing the unethical drug promotion and prescribing and formidable policies governing this issue are required to be implemented by the concerned regulatory authorities to avoid unnecessary harm to the patient’s life and pocket. Strength and weakness of study: The study explored the drug promotion and prescribing practices for the first time in a developing country however, due to sensitivity of the topic a number of respondents hesitated to participate

    Sustainability of Scientific Journals in the Developing World With Special Reference to Bangladesh

    Get PDF
    The study explores sustainability of scientific journal publication in Bangladesh. Forty-three journal editors were interviewed, and 66 current journals were physically examined for production quality, regularity of publication, and availability at concerned libraries. Findings revealed that 68% of the journals were published late, 30% had inconsistencies in typesetting, and 14% were indexed. Most journals were found either excellent or of good quality in terms of printing (85%), binding (77%), paper (92%), and graphic reproduction (76%). Most journals were not available in major libraries under study. Of the 43 editors, 28 (35%) reported a cost recovery of 1-45% from subscriptions, advertisements, and sales. About 74.4% of the editors did not consider their journals at risk. Although 86% of the editors were confident that their journals would be sustained in the long run, 37.3% could not give any convincing logic in support of their statement. Major problems include lack of skilled staff, finance, quality articles and institutional support, and lengthy peer review process. Only one journal editor was found to be a full-time editor having training in editing and publication. One-half (51%) of the editors reported have training in editing, while four had publication training. Most editors (79%) were interested in acquiring training in editing and publication. Institutional support and backup, enthusiasm and zeal of editors, unmet need for standard local journals, constant flow of funds and articles, and skilled manpower are instrumental for sustainability of science journals in Bangladesh

    COVID-19 & Pregnancy Complication During Early Pandemic: A Narrative Review

    Get PDF
    Background: Coronaviruses have caused 3 outbreaks in the past 2 decades. The novel one is SARS-COV-2, which causes COVID-19. Pregnant women have somewhat altered immune state, which may make them more vulnerable to COVID-19 and its complications. Extensive research is needed to better understand the clinical course of COVID-19 in this population. Objective: This review article discusses the comparison of previous coronaviruses’ outbreaks, clinical presentations, and complications in pregnant women and newborns. Study Design: We conducted literature search for case series and case reports about pregnancy outcomes in pregnant women with COVID-19 during the early phase of pandemic. Results: In case series, 37 of 129(28.6%) pregnant women with COVID-19 disease had preterm delivery and 14 of 67 pregnant women had fetal distress. The rate of preterm labor in normal pregnant women who are healthy and not infected with any virus worldwide is approximately 11%. Conclusion: Based on the articles reviewed, preterm delivery appears to be the most common complication in COVID-19 pregnant patients. Other complications include fetal distress, stillbirth, ICU admission and severe disease leading to fetal demise and maternal mortality. Pregnancy outcomes seem to be better with Covid-19 compared to SARs and MERS. However, most of these publications are from the early part of the pandemic when protocols for care for pregnant women were being worked out and comprehensive knowledge of the disease process in pregnant women was still in developing stage

    Risk factors for multidrug-resistant tuberculosis in urban Pakistan: A multicenter case-control study

    Get PDF
    Objective: To evaluate risk factors for multidrug-resistant tuberculosis (MDR-TB) in an urban setting of Pakistan.DESIGN AND Methods: In this multicenter case-control study, patients aged 15years old or older with sputum culture and sensitivity (C/S) diagnosed with pulmonary MDR-TB were defined as cases, whereas patients aged 15years old or older with sputum C/S diagnosed and susceptible to pulmonary TB were regarded as controls. Fifty cases and 75 controls were enrolled from three tertiary-care hospitals in Karachi.Results: Multivariable logistic regression models showed that cases were more likely to have had a TB patient in the house prior to the diagnosis of MDR-TB (adjusted odds ratio [ORadj]=3.1, 95% confidence interval [CI]: 1.2, 8.3) or had a history of prior TB treatment (ORadj=4.2, 95% CI: 1.1, 15.4). Furthermore, cases compared with controls tended to be male (ORadj=3.6, 95% CI: 1.4, 9.7), 15-25years of age (ORadj=3.7, 95% CI: 1.2, 11.3), of Sindhi ethnicity (adjusted OR=9.1, 95% CI: 1.9, 43.4) or with low educational attainment (ORadj OR=5.5, 95% CI: 1.7-17.6, for no formal schooling; ORadj=3.8, 95% CI: 1.1-14.1, 1 for 1-5 school years).CONCLUSIONS: A TB patient in the house or a history of prior TB treatment was strongly associated with MDR-TB in this study. Furthermore, younger age, male gender, Sindhi ethnicity and poor educational attainment entailed a high risk for MDR-TB. Targeted educational intervention for patients and their contacts may minimize the noncompliance with prescribed TB treatment and lessen MDR-TB magnitude in settings like Karachi

    On the Fairness of Generative Adversarial Networks (GANs)

    Get PDF
    Generative adversarial networks (GANs) are one of the greatest advances in AI in recent years. With their ability to directly learn the probability distribution of data, and then sample synthetic realistic data. Many applications have emerged, using GANs to solve classical problems in machine learning, such as data augmentation, class unbalance problems, and fair representation learning. In this paper, we analyze and highlight fairness concerns of GANs model. In this regard, we show empirically that GANs models may inherently prefer certain groups during the training process and therefore they're not able to homogeneously generate data from different groups during the testing phase. Furthermore, we propose solutions to solve this issue by conditioning the GAN model towards samples' group or using ensemble method (boosting) to allow the GAN model to leverage distributed structure of data during the training phase and generate groups at equal rate during the testing phase.Comment: submitted to International Joint Conference on Neural Networks (IJCNN) 202
    corecore