4,230 research outputs found

    Gross energy requirement in fishing operations

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    Energy is a key input into the fish harvesting process. Efficient use of energy helps in reducing operational costs and environmental impact, while increasing profits. Energy optimisation is an important aspect of responsible fishing as enunciated in the Code of Conduct for Responsible Fisheries. Gross Energy Requirement (GER) is the sum of all non-renewable energy resources consumed in making available a product or service and is expressed in energy units per physical unit of product or service delivered. GER is a measure of intensity of non-renewable resource use and it reflects the amount of depletion of earth’s inherited store of non-renewable energy in order to create and make available a product or service. In this study, GER in fish harvesting up to the point of landing is estimated in selected fish harvesting systems in the small-mechanised sectors of Indian fisheries and compared with reported results from selected non mechanised and motorised fishing systems to reflect the situation during 1997-1998. Among the fish harvesting systems studied, GER t fish-1 ranged from 5.54 and 5.91 GJ, respectively, for wooden and steel purse seiners powered by 156 hp engines; 6.40 GJ for wooden purse seiner with 235 hp engine; 25.18 GJ for mechanised gillnet/line fishing vessel with 89 hp engines; to 31.40 and 36.97 GJ, respectively, for wooden and steel trawlers powered by 99-106 hp engines

    Study of Staebler-Wronsky degradation effect in a Si:H based P-I-N solar cells

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    The objective of this study is to improve the stability and efficiency of thin solar cells with emphasis on a-Si:H devices. The research project was broken down into three main phases. The first involves designing and building a UHV glow discharge system; the second involves making good quality films and eventually efficient cells; the final phase will be analytical

    Optimal control of a large dam

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    A large dam model is an object of study of this paper. The parameters LlowerL^{lower} and LupperL^{upper} are its lower and upper levels, L=LupperLlowerL=L^{upper}-L^{lower} is large, and if a current level of water is between these bounds, then the dam is assumed to be in normal state. Passage one or other bound leads to damage. Let J1J_1 (J2)(J_2) denote the damage cost of crossing the lower (upper) level. It is assumed that input stream of water is described by a Poisson process, while the output stream is state-dependent (the exact formulation of the problem is given in the paper). Let LtL_t denote the dam level at time tt, and let p1=limtP{Lt=Llower}p_1=\lim_{t\to\infty}\mathbf{P}\{L_t= L^{lower}\}, p2=limtP{Lt>Lupper}p_2=\lim_{t\to\infty}\mathbf{P}\{L_t> L^{upper}\} exist. The long-run average cost J=p1J1+p2J2J=p_1J_1+p_2J_2 is a performance measure. The aim of the paper is to choose the parameter of output stream (exactly specified in the paper) minimizing JJ.Comment: To appear in "Journal of Applied Probability" 44 (2007), No.

    Design of Adiabatic MTJ-CMOS Hybrid Circuits

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    Low-power designs are a necessity with the increasing demand of portable devices which are battery operated. In many of such devices the operational speed is not as important as battery life. Logic-in-memory structures using nano-devices and adiabatic designs are two methods to reduce the static and dynamic power consumption respectively. Magnetic tunnel junction (MTJ) is an emerging technology which has many advantages when used in logic-in-memory structures in conjunction with CMOS. In this paper, we introduce a novel adiabatic hybrid MTJ/CMOS structure which is used to design AND/NAND, XOR/XNOR and 1-bit full adder circuits. We simulate the designs using HSPICE with 32nm CMOS technology and compared it with a non-adiabatic hybrid MTJ/CMOS circuits. The proposed adiabatic MTJ/CMOS full adder design has more than 7 times lower power consumtion compared to the previous MTJ/CMOS full adder

    A Framework for Developing Real-Time OLAP algorithm using Multi-core processing and GPU: Heterogeneous Computing

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    The overwhelmingly increasing amount of stored data has spurred researchers seeking different methods in order to optimally take advantage of it which mostly have faced a response time problem as a result of this enormous size of data. Most of solutions have suggested materialization as a favourite solution. However, such a solution cannot attain Real- Time answers anyhow. In this paper we propose a framework illustrating the barriers and suggested solutions in the way of achieving Real-Time OLAP answers that are significantly used in decision support systems and data warehouses

    Three-Dimensional Nonlinear Integral Operator with the Modelling of Majorant Function

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     تقدم هذه الورقة البحثية طريقة  لايجاد الحل التقريبي لمؤثر فولتيرا التكاملي  الثلاثي الأبعاد غير الخطي في  R3. حيث يتم استخدام مفهوم (Majorant function) وباستخدام طريقة نيوتن المعدلة  لتحويل مؤثر فولتيرا التكاملي  الثلاثي الأبعاد غير الخطي  إلى متتالية  لمؤثر فولتيرا التكاملي  الثلاثي الأبعاد الخطي ومن يتم استخدام طريقة (Gaussian-Legendre)  التربيعية لايجاد الحل التقريبي لمؤثر فولتيرا التكاملي  الثلاثي الأبعاد الخطي من خلال التعامل مع نظام جبري خطي.تم مناقشة وجود ووحدانية الحل للطريقة المستخدمة مع اعطاء أمثلة توضيحية لإظهار دقة وكفاءة الطريقة.In this paper, the process for finding an approximate solution of nonlinear three-dimensional (3D) Volterra type integral operator equation (N3D-VIOE) in R3 is introduced. The modelling of the majorant function (MF) with the modified Newton method (MNM) is employed to convert N3D-VIOE to the linear 3D Volterra type integral operator equation (L3D-VIOE). The method of trapezoidal rule (TR) and collocation points are utilized to determine the approximate solution of L3D-VIOE by dealing with the linear form of the algebraic system. The existence of the approximate solution and its uniqueness are proved, and illustrative examples are provided to show the accuracy and efficiency of the model. Mathematical Subject Classification (2010):  45P05, 45G10, 47H9

    A New Concept of Transonic Galactic Outflows in a Cold Dark Matter Halo with a Central Super-Massive Black Hole

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    We study fundamental properties of isothermal, steady and spherically symmetric galactic outflow in the gravitational potential of a cold dark matter halo and a central super-massive black hole. We find that there are two transonic solutions having different properties: each solution is mainly produced by the dark matter halo and the super-massive black hole, respectively. Furthermore, we apply our model to the Sombrero galaxy. In this galaxy, Chandra X-ray observatory detected the diffuse hot gas as the trace of galactic outflows while the star-formation rate is low and the observed gas density distribution presumably indicates the hydrostatic equilibrium. To solve this discrepancy, we propose a solution that this galaxy has a transonic outflow, however, the transonic point forms in a very distant region from the galactic center (?\sim 127 kpc). In this slowly accelerated transonic outflow, the outflow velocity is less than the sound velocity for most of the galactic halo. Since the gas density distribution in this subsonic region is similar to the hydrostatic one, it is difficult to distinguish the wide subsonic region from hydrostatic state. Such galactic outflows are dfferent from the conventional supersonic outflows observed in star-forming galaxies.Comment: 7 pages, 3 figures, accepted for publication in JPS Conference Proceedings. arXiv admin note: substantial text overlap with arXiv:1405.345

    An E-Book Building Methodology Using An Extensible Personalization Structure For Operationalizing E-Book Interface Metaphors

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    In order to address these problems, this thesis aims to identify requirements of personalization elements, to represent e-book personalization, to formalize e-book personalization components, and to develope-book packaging control and standards.Untuk menangani masalah-masalah ini, tesis ini bertujuan mengenal pasti keperluan elemen pemperibadian, untuk memperwakilkan pemperibadian e-book, untuk memformalkan komponen pemperibadian e-book, dan membangunkan pakej kawalan dan piawaian e-book

    Perception of Clinicians about Diagnostic Radiological Errors in the University of Science and Technology Hospital, Sana'a - Yemen

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    Objective: To identify the magnitude and causes of radiological errors as perceived by resident and consultant clinicians in the University of Science and Technology (UST)Hospital, Sana’a -Yemen.Methods: A questionnaire-based survey was used to assess the magnitude and causes of radiological errors. It was distributed among all clinicians in UST Hospital.Results: Of 40 residents and consultants from the UST Hospital invited to participate in the present study, 52.5%agreed to join the study. Of them, 81.0% reported the notice of diagnostic radiological errors during their daily practice,wherethe majority of daily noticed errors (64.7%) were in the range of1–10 diagnostic errors. More than half of radiological errors were reported in the interpretation of ultrasound, and abdomen was described as being the most frequent body part with diagnostic radiological errors (65.0%). The respondent clinicians thought that poor communication between radiologists and clinicians was the most frequent cause of diagnostic errors, being reported by29.0% of clinicians.However, 24.0% and 19.0% of clinicians attributed errors to the lack of experience and knowledge of radiologists, respectively.Conclusions: Errors in radiological diagnosis are still common in Yemen. Establishing a good healthcare system with a proper communication between the radiologists and clinicians is critical to identify and minimize these errors. Peer review and hands-on training are important for newly joined radiologists

    Differential evolution detection models for SMS spam

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    With the growth of mobile phones, short message service (SMS) became an essential text communication service. However, the low cost and ease use of SMS led to an increase in SMS Spam. In this paper, the characteristics of SMS spam has studied and a set of features has introduced to get rid of SMS spam. In addition, the problem of SMS spam detection was addressed as a clustering analysis that requires a metaheuristic algorithm to find the clustering structures. Three differential evolution variants viz DE/rand/1, jDE/rand/1, jDE/best/1, are adopted for solving the SMS spam problem. Experimental results illustrate that the jDE/best/1 produces best results over other variants in terms of accuracy, false-positive rate and false-negative rate. Moreover, it surpasses the baseline methods
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