• Title/Summary/Keyword: Expansion Method

Search Result 3,557, Processing Time 0.028 seconds

Weighted Integral Method for an Estimation of Displacement COV of Laminated Composite Plates (복합적층판의 변위 변동계수 산정을 위한 가중적분법)

  • Noh, Hyuk-Chun
    • Journal of the Korean Society for Advanced Composite Structures
    • /
    • v.1 no.2
    • /
    • pp.29-35
    • /
    • 2010
  • In addition to the Young's modulus, the Poisson's ratio is also at the center of attention in the field stochastic finite element analysis since the parameters play an important role in determining structural behavior. Accordingly, the sole effect of this parameter on the response variability is of importance from the perspective of estimation of uncertain response. To this end, a formulation to determine the response variability in laminate composite plates due to the spatial randomness of Poisson's ratio is suggested. The independent contributions of random Poisson's ratiocan be captured in terms of sub-matrices which include the effect of the random parameter in the same order, which can be attained by using the Taylor's series expansion about the mean of the parameter. In order to validate the adequacy of the proposed formulation, several example analyses are performed, and then the results are compared with Monte Carlo simulation (MCS). A good agreement between the suggested scheme and MCS is observed showing the adequacy of the scheme.

  • PDF

ECONOMICS OF MINI DAIRY FARMS IN SELECTED AREAS OF BANGLADESH

  • Alam, J.;Yasmin, F.;Sayeed, M.A.;Rahman, S.M.A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.8 no.1
    • /
    • pp.17-22
    • /
    • 1995
  • In this study an attempt was made to evaluate the economics of dairy farming in selected areas of Bangladesh. Data from 20 randomly selected farms were collected by survey method. Results show that cross-bred cows were more in number (2.55) in those farms than that of local cows (0.65). The number of cross-bred cows increased as the farm sizes increased. The production of milk per cross-bred cow was higher (5.66 litres) than the local ones (2.23 litres). Highest (5.74 litres) milk yield per cross-bred cow was recorded in large farms. The average lactation period for crossbred cows was higher (304 days) than the local cows (210 days). In production cost of farms, concentrates took the highest share (35.19%) followed by labour charges (23.64%). The production cost and gross returns for mini dairy farms were higher in large farms (TK. 183,005 and TK. 187,544, respectively), compared to medium and small farms. The benefit-cost ratio of all farms was 1 : 1.03, indicating that mini dairy farming is economically profitable. In addition, each farm created an annual employment opportunity of 649.70 man-days which was met by both male and female labourers. The small farms employed more female family labourers while the large farms depended more on hired labourers. The expansion of dairy farming with cross-bred cows is suggested for accelerating income and employment opportunities in rural Bangladesh.

Optimal Design of Hybrid Motor with HTPB/LOX for Air-Launch Vehicle (공중발사체를 위한 HTPB/LOX 하이브리드 모터의 최적설계)

  • Park, Bong-Kyo;Lee, Chang-Jin;Lee, Jae-Woo;Rhee, Ihn-Seok
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.32 no.4
    • /
    • pp.53-60
    • /
    • 2004
  • Optimal design of the hybrid motor has been performed for the first stage of nanosat air launch vehicle using F-4E Phantom as mother plane. Selected design variables are number of ports, the initial oxidizer flux, the combustion chamber pressure, and the nozzle expansion ratio. GBM(Gradient Based Method) and GA(Genetic Algorithm) are simultaneously used to compare the versatility of each algorithm for optimal design in this problem. Also, two objective functions of motor weight, and length are treated separatedly in the optimization to study how the objective function can affect the optimal design. The design results show that the optimal design can be successfully achieved either using GBM or GA regardless of the choice of the objective function; motor weight or length. And nanosat air launch vehicle which has total mass of 704.74kg, and length of first stage 3.74m is designed.

The Construction of Superconcentrator Based on Linear Expander Bounds (선형 팽창기 영역에 기초한 초집중기의 구성)

  • Cho Tae-Kyung;Park Byoung-Soo
    • The Journal of the Korea Contents Association
    • /
    • v.5 no.1
    • /
    • pp.179-187
    • /
    • 2005
  • Linear order Concentrators and Superconcentrators have been studied extensively for their ability to interconnect large numbers of devices in parallel, whether in communication systems or in parallel computers. One major limitation on the efficiency of parallel computer designs has been the prohibitively high cost of parallel communication between processors and memories. Linear order concentrators, O(n), can be used to construct theoretically optimal interconnection network schemes. Existing explicitly the defined constructions are based on expanders, which have large constant factors, thereby rendering them impractical lot reasonable sized networks. It demands the construction of concentrator which uses the expander with the smaller expansion constant. This paper introduces an improvement on the method of constructing concentrators using expanders, which reduce the size of resulting concentrator built from any given expander by a constant factor.

  • PDF

CGV's China Market-Oriented Growth Strategy for the Korean Wave (한류 증진을 위한 CGV의 성장 전략: 중국 시장을 중심으로)

  • Kwon, Sang-Jib
    • The Journal of the Korea Contents Association
    • /
    • v.16 no.6
    • /
    • pp.576-588
    • /
    • 2016
  • The main objective of this study is to investigate the overseas performance of CGV in order to boost Korean wave and movie platform competitiveness. The focus of this study is to on how CGV may enhance the market share of china market, emphasizing the entrepreneurial orientation of top management team and differentiated entrant strategy based on Korean wave. This study suggests key factors in the china movie platform market expansion process of CGV. In order to analyze this mechanism, we employ a case study method design. The case study results show that there are differences of CGV strategy in movie platform characteristics and the important key factors of growth depending on market situation. The most important thing is that entrepreneurial orientation of top management including differentiated entrant strategy and Korean wave-oriented vision enhance between brand loyalty and market share in china market. In addition, growing overseas impacts of CGV support on Korean wave entertainment and globalization of movie platform industry. Contributions and implications for the academic and managerial field are discussed.

A Study on the Users' Perception of Autonomous Vehicles using Q Methodology (Q 방법론을 활용한 자율주행 자동차에 대한 사용자 인식에 관한 연구)

  • Lee, Young-Jik;Ahn, Hyunchul
    • The Journal of the Korea Contents Association
    • /
    • v.20 no.5
    • /
    • pp.153-170
    • /
    • 2020
  • With the recent development of AI and ICT, autonomous vehicles are becoming a reality, and sales of the vehicles equipped with partial autonomous driving technology are also rapidly expanding. In this situation, technology research on autonomous vehicles has been actively conducted, but research on exploring the perception of autonomous vehicles from the user's perspective is relatively insufficient. Therefore, this study categorizes autonomous vehicle users into four types - , , , and . Then, it examines the characteristics of each type. For this purpose, we applied Q-methodology, a qualitative research method, to observe self-referent subjectivity of 32 P-samples using a Q-sample which consists of 34 statements. The results of our study have significance in that they provide domestic and global automakers with strategic directions for technological development and market expansion of autonomous vehicles, and academically provide hypotheses for subsequent quantitative research.

Analysis of Empathy-Related Research Trends in Social Selfare Studies (사회복지학문 분야에서 공감 관련 연구동향 분석)

  • Kweon, Sin-Jung;Kim, Kangmin
    • The Journal of the Korea Contents Association
    • /
    • v.20 no.10
    • /
    • pp.544-553
    • /
    • 2020
  • This study was intended to examine the academic role of social welfare by analysis the trends of empathic research in the field of social welfare studies in Korea, and to explore the direction and tasks to move forward. For this purpose, technical analysis and language network analysis were performed based on the category system and the frequency of simultaneous language presentation by selecting academic papers related to empathy in the field of social welfare studies in Korea from 2000 to June 2020. According to the analysis, the number of empathic studies in the social welfare field has increased steadily since 2000, and the number of studies in the last three years has increased significantly, and the research field has been mainly in the "social welfare general" category. In terms of research, the most common research was related to empathy and the relationship between other variables, while quantitative research was the most important method used in the research. As empathic-related research increase in social welfare studies, such research results require efforts such as expansion of research field and research contents and attempts of various research methods.

A Study of Reserve Book System (지정도서제도에 관한 연구)

  • 고성수
    • Journal of Korean Library and Information Science Society
    • /
    • v.4
    • /
    • pp.1-38
    • /
    • 1977
  • This paper intend to analyze, review and point out the actual conditions of "Reserve Book System" of university libraries in Korea, then to present several proposals. I took six national universities and six private universities as researching objects and the materials were collected by questionnaires. 1) There are so many libraries which have no seperate reserve books room, while every colleges, and their departments are putting into forces the reserve book system. This makes many unresonable problems. 2) Many volumes were not adequate to the courses of each depertment and so many problems arose to set up reserve books owing to Lhe lack of library budget. 3) Insincerities of professors and librarians make no good conditions for the reserve book system. 4) For insufficiency of understanding about the reserve book system cf professors and students with university authorities, we must persuade and guide them about this system. 5) We imust evaluate about the problems of the reserve book system. I show the methods which is necessary to solve the problems of this system in the following. 1) As to methods of improving the field of menagement for running about the reserve book system, a) Establishment of the independent reserve books room. b) Gradual expansion of the reserve book system. c) Evaluation of the actual using of reserve books. 2) As to contents to improve the reserve book system, a) Improving the selection method of reserve books. b) Increasing the library budget enable to purchase more reserve books. c) Making more close connections between the curricula ard reserve books. 3) Settlment of coordinating system for carrying out reserve book system, a) We must have mutual understanding and co-operation among university authorities, faculties and libraries. b) We must have co-operation between professors and librariars.ibrariars.

  • PDF

A Qualitative Study on the Learning Outcome of PBL Instruction (PBL 수업적용에 따른 학습 성과에 관한 질적 연구)

  • Kim, Kyung-Hwa
    • The Journal of the Korea Contents Association
    • /
    • v.17 no.12
    • /
    • pp.191-201
    • /
    • 2017
  • The purpose of this study was to examine the learning outcome of problem-based learning as an efficient teaching method to improve the competencies of great talents for future society. A general education course of a university that was one of teaching profession courses titled "prevention of school violence and countermeasures" was provided in the form of PBL, and data were gathered, which were reflective journals, evaluation sheet and observational journals. As a result, PBL produced learning effects such as understanding and applying learning contents, fostering cooperativeness, problem-solving skills and a sense of responsibility, extended thinking and good understanding of PBL. Also, that provided a great opportunity for the students to build up their character by learning caring and by improving cooperativeness, a sense of responsibility and communicative competency, which preservice teachers should have. The findings of the study suggest that the expansion of PBL is necessary to bolster problem- solving skills, self-directed learning, cooperativeness and creativity that are competencies required in the era of the Fourth Industrial Revolution.

The development of a GIS-based gas accident management system (GIS 기반의 가스사고 관리시스템 개발에 대한 연구)

  • Kim, Kye-Hyun;Kim, Tae-Il;Park, Tae-Og
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.10 no.2 s.20
    • /
    • pp.97-105
    • /
    • 2002
  • Nowadays the gas utilities has been increasing constantly due to the expansion of the urban areas. The gas utility companies have adopted GIS technologies and been trying to computerize the management system for gas facilities to maintain up-to-dated information to forecast possible accidents and to minimize the casualties from the accidents. The major objective of this study is to develop a GIS-based gas accident management system which could facilitate early response and alternatives in the cases of the accidents. The system is able to provide the information for the pipes to be closed followed by selecting the location of the accident, and search all the relevant values connected to the location to provide all the information to minimize the casualties. In addition to that, the system can calculated the remaining amount of the gas in the pipes closed from the accident thereby providing more safer alternatives. In the future, more practical method needs to be made such as GPS-linked more integrated gas accident management system.

  • PDF