Search results for: eigenvalue problems
4643 Experiences of Patients Living with Peritoneal Dialysis: A Qualitative Study
Authors: Xuzhen Yang, Yan Shan, Yabo Ding, Keke DIao, Yanjun Zhang, Yijia Huang
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Purpose: Our aim is to understand the unique experiences of patients with peritoneal dialysis and how they deal with issues brought on by disease and dialysis. Patients and Methods: Semi-structured interview was designed to collect information, and inpatients with peritoneal dialysis in a university-based tertiary hospital in the central province of China were purposively chosen as interviewees. The content analysis method was used to analyze the data. Results: Nine patients participated in the study, and three themes and eight subthemes were generated. Conclusion: Patients using peritoneal dialysis encounter numerous challenges and problems in the process of disease and dialysis, and they took attempt to cope with them well to adapt to living with peritoneal dialysis.Keywords: peritoneal dialysis, experience, patient, coping strategy
Procedia PDF Downloads 1004642 Tax Evasion in Brazil: The Case of Specialists
Authors: Felippe Clemente, Viviani S. Lírio
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Brazilian tax evasion is very high. It causes many problems for economics as budget realization, income distribution and no allocation of productive resources. Therefore, the purpose of this article is to use the instrumental game theory to understand tax evasion agents and tax authority in Brazil (Federal Revenue and Federal Police). By means of Game Theory approaches, the main results from considering cases both with and without specialists show that, in a high dropout situation, penalizing taxpayers with either high fines or deprivations of liberty may not be very effective. The analysis also shows that audit and inspection costs play an important role in driving the equilibrium system. This would suggest that a policy of investing in tax inspectors would be a more effective tool in combating non-compliance with tax obligations than penalties or fines.Keywords: tax evasion, Brazil, game theory, specialists
Procedia PDF Downloads 3294641 Merit Measures and Validation in Employee Evaluation and Selection
Authors: Wilson P. R. Malebye, Solly M. Seeletse
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Applicants for space in selection problems are usually compared subjectively, and the selection made are not reliable and often cannot be verified scientifically. The paper illustrates objective selection by involving a mathematical measure in selecting a candidate applying for a job, and then using other two independent measures, validates the choice made. The scientific process followed is SToR (SAW, TOPSIS, WP) in which Simple Additive Weighting (SAW) is used to select, and the TOPSIS (technique for order preference by similarity to ideal solution) and weighted product (WP) are used to validate. A practical exercise was obtained from a factual selection problem in a recruitment task undertaken in an organization in which the authors consulted, and their Human Resources (HR) department wanted to check if their selection was justifiable. The result was that our approach was consistent and convincing to that HR, and theirs was not because our selection was satisfactory while theirs could not be corroborated using any method.Keywords: candidate selection, SToR, SW, TOPSIS, WP
Procedia PDF Downloads 3454640 Parallel 2-Opt Local Search on GPU
Authors: Wen-Bao Qiao, Jean-Charles Créput
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To accelerate the solution for large scale traveling salesman problems (TSP), a parallel 2-opt local search algorithm with simple implementation based on Graphics Processing Unit (GPU) is presented and tested in this paper. The parallel scheme is based on technique of data decomposition by dynamically assigning multiple K processors on the integral tour to treat K edges’ 2-opt local optimization simultaneously on independent sub-tours, where K can be user-defined or have a function relationship with input size N. We implement this algorithm with doubly linked list on GPU. The implementation only requires O(N) memory. We compare this parallel 2-opt local optimization against sequential exhaustive 2-opt search along integral tour on TSP instances from TSPLIB with more than 10000 cities.Keywords: parallel 2-opt, double links, large scale TSP, GPU
Procedia PDF Downloads 6294639 Solving the Pseudo-Geometric Traveling Salesman Problem with the “Union Husk” Algorithm
Authors: Boris Melnikov, Ye Zhang, Dmitrii Chaikovskii
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This study explores the pseudo-geometric version of the extensively researched Traveling Salesman Problem (TSP), proposing a novel generalization of existing algorithms which are traditionally confined to the geometric version. By adapting the "onion husk" method and introducing auxiliary algorithms, this research fills a notable gap in the existing literature. Through computational experiments using randomly generated data, several metrics were analyzed to validate the proposed approach's efficacy. Preliminary results align with expected outcomes, indicating a promising advancement in TSP solutions.Keywords: optimization problems, traveling salesman problem, heuristic algorithms, “onion husk” algorithm, pseudo-geometric version
Procedia PDF Downloads 2094638 A Comparative Study of Virus Detection Techniques
Authors: Sulaiman Al amro, Ali Alkhalifah
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The growing number of computer viruses and the detection of zero day malware have been the concern for security researchers for a large period of time. Existing antivirus products (AVs) rely on detecting virus signatures which do not provide a full solution to the problems associated with these viruses. The use of logic formulae to model the behaviour of viruses is one of the most encouraging recent developments in virus research, which provides alternatives to classic virus detection methods. In this paper, we proposed a comparative study about different virus detection techniques. This paper provides the advantages and drawbacks of different detection techniques. Different techniques will be used in this paper to provide a discussion about what technique is more effective to detect computer viruses.Keywords: computer viruses, virus detection, signature-based, behaviour-based, heuristic-based
Procedia PDF Downloads 4864637 Improve the Provisions in the Life Imprisonment Law in Vietnam
Authors: Nguyen Xuan Thuy
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The provisions on life imprisonment in the legal system enable to differentiate criminal liability and individualize the penalties for particularly serious crimes. This punishment acts as an intermediary between the determined imprisonment of a maximum of 20 years and the capital punishment, enabling the penalty system to maintain its internal unity. However, the practice of applying the punishment has been posing many problems that need to be studied in order to come up with solutions to improve the provisions related to the penalty and its effectiveness in the fight against crimes. The article summarizes the law on life imprisonment sentence in the current criminal law to highlight its characteristics and role in Vietnam's Penal Code. It also suggests some solutions to improve the law and its effectiveness in preventing and combating crimes.Keywords: life imprisonment, Vietnam, law, penalty, provisions
Procedia PDF Downloads 984636 Classification of Equations of Motion
Authors: Amritpal Singh Nafria, Rohit Sharma, Md. Shami Ansari
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Up to now only five different equations of motion can be derived from velocity time graph without needing to know the normal and frictional forces acting at the point of contact. In this paper we obtained all possible requisite conditions to be considering an equation as an equation of motion. After that we classified equations of motion by considering two equations as fundamental kinematical equations of motion and other three as additional kinematical equations of motion. After deriving these five equations of motion, we examine the easiest way of solving a wide variety of useful numerical problems. At the end of the paper, we discussed the importance and educational benefits of classification of equations of motion.Keywords: velocity-time graph, fundamental equations, additional equations, requisite conditions, importance and educational benefits
Procedia PDF Downloads 7874635 Discrete Element Modeling on Bearing Capacity Problems
Authors: N. Li, Y. M. Cheng
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In this paper, the classical bearing capacity problem is re-considered from discrete element analysis. In the discrete element approach, the bearing capacity problem is considered from the elastic stage to plastic stage to rupture stage (large displacement). The bearing capacity failure mechanism of a strip footing on soil is investigated, and the influence of micro-parameters on the bearing capacity of soil is also observed. It is found that the distinct element method (DEM) gives very good visualized results, and basically coincides well with that derived by the classical methods.Keywords: bearing capacity, distinct element method, failure mechanism, large displacement
Procedia PDF Downloads 3664634 Grid Computing for Multi-Objective Optimization Problems
Authors: Aouaouche Elmaouhab, Hassina Beggar
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Solving multi-objective discrete optimization applications has always been limited by the resources of one machine: By computing power or by memory, most often both. To speed up the calculations, the grid computing represents a primary solution for the treatment of these applications through the parallelization of these resolution methods. In this work, we are interested in the study of some methods for solving multiple objective integer linear programming problem based on Branch-and-Bound and the study of grid computing technology. This study allowed us to propose an implementation of the method of Abbas and Al on the grid by reducing the execution time. To enhance our contribution, the main results are presented.Keywords: multi-objective optimization, integer linear programming, grid computing, parallel computing
Procedia PDF Downloads 4864633 A Class of Third Derivative Four-Step Exponential Fitting Numerical Integrator for Stiff Differential Equations
Authors: Cletus Abhulimen, L. A. Ukpebor
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In this paper, we construct a class of four-step third derivative exponential fitting integrator of order six for the numerical integration of stiff initial-value problems of the type: y’= f(x,y); y(x₀) =y₀. The implicit method has free parameters which allow it to be fitted automatically to exponential functions. For the purpose of effective implementation of the proposed method, we adopted the techniques of splitting the method into predictor and corrector schemes. The numerical analysis of the stability of the new method was discussed; the results show that the method is A-stable. Finally, numerical examples are presented, to show the efficiency and accuracy of the new method.Keywords: third derivative four-step, exponentially fitted, a-stable, stiff differential equations
Procedia PDF Downloads 2674632 Image Processing and Calculation of NGRDI Embedded System in Raspberry
Authors: Efren Lopez Jimenez, Maria Isabel Cajero, J. Irving-Vasqueza
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The use and processing of digital images have opened up new opportunities for the resolution of problems of various kinds, such as the calculation of different vegetation indexes, among other things, differentiating healthy vegetation from humid vegetation. However, obtaining images from which these indexes are calculated is still the exclusive subject of active research. In the present work, we propose to obtain these images using a low cost embedded system (Raspberry Pi) and its processing, using a set of libraries of open code called OpenCV, in order to obtain the Normalized Red-Green Difference Index (NGRDI).Keywords: Raspberry Pi, vegetation index, Normalized Red-Green Difference Index (NGRDI), OpenCV
Procedia PDF Downloads 2924631 Research on Building Urban Sustainability along the Coastal Area in China
Authors: Sun Jiaojiao, Fu Jiayan
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At present, in China, the research about the urban sustainability construction is still in the exploratory stage. The ecological problems of the coastal area are more sensitive and complicated. In the background of global warming with serious ecological damage, this paper deeply researches on the main characteristics of urban sustainability and measures how to build urban sustainability. Through combination with regional environmental and economic ability along the coastal area, we put forward the system planning framework, construction strategy and the evaluation index system in order to seek the way of building urban sustainability along coastal area in China.Keywords: urban sustainability, coastal areas, construction strategy, evaluation index system
Procedia PDF Downloads 6034630 CO2 Emissions Quantification of the Modular Bridge Superstructure
Authors: Chanhyuck Jeon, Jongho Park, Jinwoong Choi, Sungnam Hong, Sun-Kyu Park
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Many industries put emphasis on environmentally-friendliness as environmental problems are on the rise all over the world. Among themselves, the Modular Bridge research is going on. Also performing cross-section optimization and duration reducing, this research aims at developing the modular bridge with Environment-Friendliness and economic feasibility. However, the difficulty lies in verifying environmental effectiveness because there are no field applications of the modular bridge until now. Therefore, this thesis is categorized according to the form of the modular bridge superstructure and assessed CO₂ emission quantification per work types and materials according to each form to verify the environmental effectiveness of the modular bridge.Keywords: modular bridge, CO2 emission, environmentally friendly, quantification, carbon emission factor, LCA (Life Cycle Assessment)
Procedia PDF Downloads 5584629 Interlingual Translation of Manipuri Folktales with the Ideas of André Lefevere's Translation
Authors: Thoudam Jomita Devi
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This paper is an attempt to analyze the problems of translating Manipuri folktales into English and the strategies deployed. In Manipuri, folktales are known as Fungawari/Phungawari, which is similar to a western bed time story. The work is with the special reference to folktales of Meetei community. Meetei are the majority ethnic group of Manipur, India. For this paper’s purpose, two folktales Shandrembi Cheisra and Pebet will be chosen for analysis and discussion. The translation of folktales can contribute to intercultural communication and bridge the gap between the generations. Translating Manipuri Folktales is problematic on both cultural and linguistic levels. Therefore, the aim of this analysis is to understand, how the idea of André Lefevere (1992) translation could be implicated in translating Manipuri folktales.Keywords: cultural, folktales, intercultural, interlingual, translation
Procedia PDF Downloads 1874628 A Study of Chromatic Uniqueness of W14
Authors: Zainab Yasir Al-Rekaby, Abdul Jalil M. Khalaf
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Coloring the vertices of a graph such that every two adjacent vertices have different color is a very common problem in the graph theory. This is known as proper coloring of graphs. The possible number of different proper colorings on a graph with a given number of colors can be represented by a function called the chromatic polynomial. Two graphs G and H are said to be chromatically equivalent, if they share the same chromatic polynomial. A Graph G is chromatically unique, if G is isomorphic to H for any graph H such that G is chromatically equivalent to H. The study of chromatically equivalent and chromatically unique problems is called chromaticity. This paper shows that a wheel W14 is chromatically unique.Keywords: chromatic polynomial, chromatically Equivalent, chromatically unique, wheel
Procedia PDF Downloads 4154627 Sports: A Vital Tool for Promotion of Good Health and Prevention of Diseases
Authors: Agburuga Obi, Madumere Akuego Jane
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This paper explores the important role sports can play in the promotion of good health and prevention of diseases. Technological advancements in today’s world has come along with some difficulties to man. This is because work formally done by man has been taken over by machines, thus, man has become sedentary. This has created a lot of health problems to man such as cardiovascular diseases, diabetes, cancer, obesity, and osteoporosis. To nip this ugly situation in the bud, the following recommendations are made: specific measures should be taken to raise the awareness within the government, key sectors and the population of the diverse benefits or physical activity and sports and the risk and costs of inactivity, provision of equipment, facilities for sports and recreational activities in every community, participation in physical activities in sports if not on daily basis at least thrice a week.Keywords: physical activities, sport, good health, prevention, diseases
Procedia PDF Downloads 7714626 A Review on Applications of Experts Systems in Medical Sciences
Authors: D. K. Sreekantha, T. M. Girish, R. H. Fattepur
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In this article, we have given an overview of medical expert systems, which can be used for the developed of physicians in making decisions such as appropriate, prognostic, and therapeutic decisions which help to organize, store, and gives appropriate medical knowledge needed by physicians and practitioners during medical operations or further treatment. If they support the studies by using these systems, advanced tools in medicine will be developed in the future. New trends in the methodology of development of medical expert systems have also been discussed in this paper. So Authors would like to develop an innovative IT based solution to help doctors in rural areas to gain expertise in Medical Science for treating patients. This paper aims to survey the Soft Computing techniques in treating patient’s problems used throughout the world.Keywords: expert system, fuzzy logic, knowledge base, soft computing, epilepsy
Procedia PDF Downloads 2564625 Interval Estimation for Rainfall Mean in Northeastern Thailand
Authors: Nitaya Buntao
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This paper considers the problems of interval estimation for rainfall mean of the lognormal distribution and the delta-lognormal distribution in Northeastern Thailand. We present here the modified generalized pivotal approach (MGPA) compared to the modified method of variance estimates recovery (MMOVER). The performance of each method is examined in term of coverage probabilities and average lengths by Monte Carlo simulation. An extensive simulation study indicates that the MMOVER performs better than the MGPA approach in terms of the coverage probability; it results in highly accurate coverage probability.Keywords: rainfall mean, interval estimation, lognormal distribution, delta-lognormal distribution
Procedia PDF Downloads 4564624 Architecture of a Preliminary Course on Computational Thinking
Authors: Mintu Philip, Renumol V. G.
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An introductory programming course is a major challenge faced in Computing Education. Many of the introductory programming courses fail because student concentrate mainly on writing programs using a programming language rather than involving in problem solving. Computational thinking is a general approach to solve problems. This paper proposes a new preliminary course that aims to develop computational thinking skills in students, which may help them to become good programmers. The proposed course is designed based on the four basic components of computational thinking - abstract thinking, logical thinking, modeling thinking and constructive thinking. In this course, students are engaged in hands-on problem solving activities using a new problem solving model proposed in this paper.Keywords: computational thinking, computing education, abstraction, constructive thinking, modelling thinking
Procedia PDF Downloads 4574623 Inter-Cell-Interference Mitigation Scheme in Wireless Communication System
Authors: Jae-Hyun Ro, Yong-Jun Kim, Eui-Hak Lee, Hyoung-Kyu Song
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Mobile communication has been developing very rapidly since it appeared. However, although mobile communication market has been rapidly developing, many mobile users are not offered good quality of service (QoS) due to increment of the amount of data traffic. Recently, femtocell is very hot issue in mobile communication because femtocell can solve the problems of data traffic and offer better QoS to mobile users. However, the deployment of femtocell in existing macrocell coverage area is not so simple due to the influence of inter-cell-interference (ICI) with existing macrocell. Thus, this paper proposes femtocell scheme which is able to reduce the influence of ICI to deploy femtocell easily.Keywords: CDD, femtocell, interference, macrocell, OFDM
Procedia PDF Downloads 5024622 Risk Identification of Investment Feasibility in Indonesia’s Toll Road Infrastructure Investment
Authors: Christo Februanto Putra
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This paper presents risk identification that affects investment feasibility on toll road infrastructure in Indonesia using qualitative methods survey based on the expert practitioner in investor, contractor, and state officials. The problems on infrastructure investment in Indonesia, especially on KPBU model contract, is many risk factors in the investment plan is not calculated in detail thoroughly. Risk factor is a value used to provide an overview of the risk level assessment of an event which is a function of the probability of the occurrence and the consequences of the risks that arise. As results of the survey which is to show which risk factors impacts directly to the investment feasibility and rank them by their impacts on the investment.Keywords: risk identification, indonesia toll road, investment feasibility
Procedia PDF Downloads 2804621 Ecorium: The Ecological Project in Montevideo Uruguay
Authors: Chettou Souhaila, Soufi Omar, Roumia Mohammed Ammar
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Protecting the environment is to preserve the survival and future of humanity. Indeed, the environment is our source of food and drinking water, the air is our source of oxygen, the climate allows our survival and biodiversity are a potential drug reservoir. Preserving the environment is, therefore, a matter of survival. The objective of this project is to familiarize the general public with environmental problems not only with the theme of environmental protection, but also with the concept of biodiversity in different ecosystems. For it, the aim of our project was to create the Ecorium which is a place that preserves many species of plants of different ecosystems, schools, malls, buildings, offices, ecological transports, gardens, and many familial activities that participated in the ecosystems development, strategic biodiversity and sustainable development.Keywords: ecological system, ecorium, environment, sustainable development
Procedia PDF Downloads 3424620 Consumer Complicity toward Luxury in Developing Countries
Authors: Marisa Hakim
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After all, collectivism moderate is one of the biggest issues that drive complicit behavior toward luxury in Indonesia and Thailand. The nature of collectivism that we find on this research would probably break the problems of the gap about the nature of complicit behavior. Precisely, we could probably drive to the further research about: 'Is there any pattern to describe consumer behavior toward counterfeit luxury goods among market in developing countries? Furthermore, is there any possibility to manipulate that pattern and bring the new concept of local/traditional luxury teste toward consumers in developing countries?'Keywords: complicity, consumer complicity, counterfeit, consumer behavior, luxury goods, marketing, Indonesia, Thailand
Procedia PDF Downloads 2704619 Bayesian Analysis of Change Point Problems Using Conditionally Specified Priors
Authors: Golnaz Shahtahmassebi, Jose Maria Sarabia
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In this talk, we introduce a new class of conjugate prior distributions obtained from conditional specification methodology. We illustrate the application of such distribution in Bayesian change point detection in Poisson processes. We obtain the posterior distribution of model parameters using a general bivariate distribution with gamma conditionals. Simulation from the posterior is readily implemented using a Gibbs sampling algorithm. The Gibbs sampling is implemented even when using conditional densities that are incompatible or only compatible with an improper joint density. The application of such methods will be demonstrated using examples of simulated and real data.Keywords: change point, bayesian inference, Gibbs sampler, conditional specification, gamma conditional distributions
Procedia PDF Downloads 1894618 Practical Approach to Development Automated System of Record Research Results Architectural Cultural Heritage Objects Island-Town Sviyazhsk
Authors: Timur R. Azizov, Eugenia F. Shaykhutdinova, Ayrat G. Sitdikov
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In this article, we consider problems of automatic research result analysis and current monitoring of cultural legacy objects in island-city Sviyazhsk. We make basic concept of creating Automatic system, including developing the knowledge library with all conditions of three historical objects. In addition, we made described process of developing Automatic system of research result analysis of cultural legacy objects in island-city Sviyazhsk.Keywords: automated system, record, results of research, unity3D, ASP .NET
Procedia PDF Downloads 2454617 Development of Instructional Material Using Scientific Approach to Make the Nature of Science (NOS) and Critical Thinking Explicit on Chemical Bonding and Intermolecular Forces Topics
Authors: Ivan Ashif Ardhana, Intan Mahanani
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Chemistry education tends to change from triplet representation among macroscopic, microscopic, and symbolic to tetrahedron shape. This change set the aspect of human element on the top of learning. Meaning that students are expected to solve the problems involving the ethic, morality, and humanity through the class. Ability to solve the problems connecting either theories or applications is called scientific literacy which have been implemented in curriculum 2013 implicitly. Scientific literacy has an aspect of nature science and critical thinking. Both can be integrated to learning using scientific approach and scientific inquiry. Unfortunately, students’ ability of scientific literacy in Indonesia is far from expectation. A survey from PISA had proven it. Scientific literacy of Indonesian students is always at bottom five position from 2002 till 2012. Improving a scientific literacy needs many efforts against them. Developing an instructional material based on scientific approach is one kind of that efforts. Instructional material contains both aspect of nature of science and critical thinking which is instructed explicitly to improve the students’ understanding about science. Developing goal is to produce a prototype and an instructional material using scientific approach whose chapter is chemical bonding and intermolecular forces for high school students grade ten. As usual, the material is subjected to get either quantitative mark or suggestion through validation process using validation sheet instrument. Development model is adapted from 4D model containing four steps. They are define, design, develop, and disseminate. Nevertheless, development of instructional material had only done until third step. The final step wasn’t done because of time, cost, and energy limitations. Developed instructional material had been validated by four validators. They are coming from chemistry lecture and high school’s teacher which two at each. The result of this development research shown the average of quantitative mark of students’ book is 92.75% with very proper in criteria. Given at same validation process, teacher’s guiding book got the average mark by 96.98%, similar criteria with students’ book. Qualitative mark including both comments and suggestions resulted from validation process were used as consideration for the revision. The result concluded us how the instructional materials using scientific approach to explicit nature of science and critical thinking on the topic of chemical bonding and intermolecular forces are very proper if they are used at learning activity.Keywords: critical thinking, instructional material, nature of science, scientific literacy
Procedia PDF Downloads 2654616 Congruences Induced by Certain Relations on Ag**-Groupoids
Authors: Faisal Yousafzai, Murad-ul-Islam Khan, Kar Ping Shum
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We introduce the concept of partially inverse AG**-groupoids which is almost parallel to the concepts of E-inversive semigroups and E-inversive E-semigroups. Some characterization problems are provided on partially inverse AG**-groupoids. We give necessary and sufficient conditions for a partially inverse AG**-subgroupoid E to be a rectangular band. Furthermore, we determine the unitary congruence η on a partially inverse AG**-groupoid and show that each partially inverse AG**-groupoid possesses an idempotent separating congruence μ. We also study anti-separative commutative image of a locally associative AG**-groupoid. Finally, we give the concept of completely N-inverse AG**-groupoid and characterize a maximum idempotent separating congruence.Keywords: AG**-groupoids, congruences, inverses, rectangular band
Procedia PDF Downloads 3424615 Expansion of Subjective Learning at Japanese Universities: Experiential Learning Based on Social Participation
Authors: Kumiko Inagaki
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Qualitative changes to the undergraduate education have recently become the focus of attention in Japan. This is occurring against the backdrop of declining birthrate and increasing university enrollment, as well as drastic societal changes of advance toward globalization and a knowledge-based society. This paper describes the cases of Japanese universities that promoted various forms of experiential learning around the theme of social participation. The opportunity of learning through practical experience, where students turn their attention to social problems and take pains to consider means of resolving them, creates opportunities to demonstrate “human power” applicable to all sorts of activities the following graduation, thereby guaranteeing students’ continuous growth throughout their careers.Keywords: career education, experiential learning, subjective learning, university education
Procedia PDF Downloads 3114614 Robust Processing of Antenna Array Signals under Local Scattering Environments
Authors: Ju-Hong Lee, Ching-Wei Liao
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An adaptive array beamformer is designed for automatically preserving the desired signals while cancelling interference and noise. Providing robustness against model mismatches and tracking possible environment changes calls for robust adaptive beamforming techniques. The design criterion yields the well-known generalized sidelobe canceller (GSC) beamformer. In practice, the knowledge of the desired steering vector can be imprecise, which often occurs due to estimation errors in the DOA of the desired signal or imperfect array calibration. In these situations, the SOI is considered as interference, and the performance of the GSC beamformer is known to degrade. This undesired behavior results in a reduction of the array output signal-to-interference plus-noise-ratio (SINR). Therefore, it is worth developing robust techniques to deal with the problem due to local scattering environments. As to the implementation of adaptive beamforming, the required computational complexity is enormous when the array beamformer is equipped with massive antenna array sensors. To alleviate this difficulty, a generalized sidelobe canceller (GSC) with partially adaptivity for less adaptive degrees of freedom and faster adaptive response has been proposed in the literature. Unfortunately, it has been shown that the conventional GSC-based adaptive beamformers are usually very sensitive to the mismatch problems due to local scattering situations. In this paper, we present an effective GSC-based beamformer against the mismatch problems mentioned above. The proposed GSC-based array beamformer adaptively estimates the actual direction of the desired signal by using the presumed steering vector and the received array data snapshots. We utilize the predefined steering vector and a presumed angle tolerance range to carry out the required estimation for obtaining an appropriate steering vector. A matrix associated with the direction vector of signal sources is first created. Then projection matrices related to the matrix are generated and are utilized to iteratively estimate the actual direction vector of the desired signal. As a result, the quiescent weight vector and the required signal blocking matrix required for performing adaptive beamforming can be easily found. By utilizing the proposed GSC-based beamformer, we find that the performance degradation due to the considered local scattering environments can be effectively mitigated. To further enhance the beamforming performance, a signal subspace projection matrix is also introduced into the proposed GSC-based beamformer. Several computer simulation examples show that the proposed GSC-based beamformer outperforms the existing robust techniques.Keywords: adaptive antenna beamforming, local scattering, signal blocking, steering mismatch
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