• Title/Summary/Keyword: Unsuitable

Search Result 662, Processing Time 0.028 seconds

Finite Element Analysis of Incompressible Transient Navier-Stokes Equation using Fractional-Step Methods (Fractional-Step법을 이용한 비압축성 비정상 Navier-Stokes 방정식의 유한 요소해석)

  • Kim, Hyung-Min;Lee, Shin-Pyo
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.27 no.4
    • /
    • pp.458-465
    • /
    • 2003
  • The main objective of the research is to develop a research code solving transient incompressible Navier-Stokes equation. In this research code, Adams-Bashforth method was applied to the convective terms of the navier stokes equation and the splitted equations were discretized spatially by finite element methods to solve the complex geometry problems easily. To reduce the divergence on the boundaries of pressure poisson equation due to the unsuitable pressure boundary conditions, multi step approximation pressure boundary conditions derived from the boundary linear momentum equations were used. Simulations of Lid Driven Flow and Flow over Cylinder were conducted to prove the accuracy by means of the comparison with results of the previous workers.

Characteristics of Temperature Control in the Inverter Type Oil Coolers (인버터 타입 오일냉각기의 온도제어 특성에 관한 연구)

  • 이상호;이찬홍;박천홍
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 2003.10a
    • /
    • pp.233-236
    • /
    • 2003
  • In this Paper, the temperature control error and cooling characteristics of inverter typ coolers are evaluated to predict application validity of coolers under heating pattern and amount The temperature control error of coolers small in 15~70% range of the max. cooling ability. At less than 15% of max. cooling ability has the inverter type cooler a basic temperature control error $\pm0.5^{\circ}C$ and acts as on/off type coolers. The inverter type cooler is unsuitable for precision temperature control under the complex heating pattern. But PID control of cooler including the heating system is an alternative for the case.

  • PDF

Performance Analysis of Backoff Algorithm in Wireless LANs with Prioritized Messages (무선랜 환경에서 우선순위를 고려한 백오프 알고리듬 성능분석)

  • Jeong Seok-Yun;Heo Seon
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2006.05a
    • /
    • pp.1656-1660
    • /
    • 2006
  • Distributed coordination function(DCF) is the primary random access mechanism of IEEE 802.11, which is the basic protocol of wireless LAN based on the CSMA/CA protocol. It enables fast installation with minimal management and maintenance costs and is a very robust protocol for the best effort service in wireless medium. The current DCF, however, is known to be unsuitable for real-time applications such as voice message transmission. In this paper, we focus on the performance issues of IEEE 802.11 which accommodate the prioritized messages. Existing results use the initial window size and backoff window-increasing factor as tools to handle the priority of the messages. Instead, we introduce a novel scheme which chooses the backoff timer with arbitrary probabilities. By this, one can greatly reduce the backoff delay of the lower priority messages without degrading the performance of higher priority.

  • PDF

The Pattern Standardization of Ready-made Korean Traditional Costume for Women in Twenties (여자한복의 기성복화를 위한 패턴개발-20대를 중심으로-)

  • 강순제;황의숙;남윤자;조효숙;홍나영
    • Journal of the Korean Society of Costume
    • /
    • v.44
    • /
    • pp.77-89
    • /
    • 1999
  • The present study aims at developing standardized patterns of ready-made Korean traditional costume for women in twenties and at suggesting classified standards so that consumers can buy high quailty clothes easily without dissatisfaction on unsuitable measurments. It was found from the dressing experiment results that new-concept patterns of Korean jackets onsidering women's bodies were seriously required because jackets fabricated by conventional patterns were not properily fitted to their bodies. During the processes of patten development, dressing experiment, and subsequent pattern adjustment, measurment standards classified by women's bodies were established, and new standardized patterns were developed in accordance with characteristics of women's bodies. These findings suggested that future studies on the pattern modification should be achieved continuously in consideration of ages, tastes, and fashions of modern women consumers.

  • PDF

Trichinosis Caused by Ingestion of Raw Soft-Shelled Turtle Meat in Korea

  • Lee, Sang-Rok;Yoo, Sang-Hoon;Kim, Hyun-Seon;Lee, Seung-Ha;Seo, Min
    • Parasites, Hosts and Diseases
    • /
    • v.51 no.2
    • /
    • pp.219-221
    • /
    • 2013
  • Reptiles, unlike mammals, have been considered to be unsuitable hosts of Trichinella spp., though larvae have been detected in their muscles and human outbreaks related to their consumption have, in fact, occurred. Herein we report 2 Korean cases of trichinosis, possibly transmitted via consumption of reptile meat. Both patients suffered from myalgia, headache, and facial edema. Laboratory examinations revealed leukocytosis with eosinophilia (54% and 39%, respectively) and elevated creatinine phosphokinase. ELISA was performed under the suspicion of trichinosis, showing positivity at the 29th and 60th day post-infection. Since they had consumed raw soft-shelled turtle meat, turtle was strongly suggested to be an infection source of trichinosis in Korea next to the wild boar and badger.

Effect of Sugar Starvation on the Sugar Transport System in Suspension Cultures of Streptanthus trotus (Streptanthus tortus 배양 세포에서 당류고갈이 당류 수송계에 미치는 영향)

  • 조봉희
    • Korean Journal of Plant Tissue Culture
    • /
    • v.27 no.1
    • /
    • pp.47-50
    • /
    • 2000
  • In suspension cultures of Streptanthus. the uptake rate of sugar was increased during the ceil starvation of sugar in the medium. The maximal uptake rate obtained with 3 days of cell starvation. Sugar transport system induced by the sugar starvation was completely inhibited by 10 $\mu$M cycloheximide. Plant cells are known to possess only one sugar transport system, but the uptake rate of glucose obtained a saturated kinetic while the one of sucrose had two different kinetics after the sugar starvation. Induced sugar transport systems had different kinetics compared to plant cell. These results showed that higher plants have adaptable ability to induce new sugar transport systems when the environment changed unsuitable.

  • PDF

The Present and Future of Pheasant Raising in Korea (꿩의 생산기술 현황과 생산전망)

  • 양영훈
    • Korean Journal of Poultry Science
    • /
    • v.23 no.3
    • /
    • pp.153-160
    • /
    • 1996
  • Though pheasants (Korean ring-necked pheasant) have been raised for several decades, their behavior and wild nature are far from domestication. The pheasant is a seasonal breeding species and lays a limited number of eggs in a breeding season. The growth rate and feed efficiency of pheasants are very low as compaired with those of chicken for meat purpose. In addition, the breeder's access to one's herd for care is not easy. From these reasons, pheasants seem to be unsuitable for meat production in a large flock at present. However, pheasant raising is expected to increase slowly in accordance with rising demand for special poultry meat. Therefore, it is necessary to improve techniques about raising, feeding and rnanagement, so that the consumer price of pheasant meat can be lowered down reasonably.

  • PDF

The Calculation of New Dimension & Tolerance due to Change of Datum of Dimension -Development of Interactive Computer Program- (기준(基準)의 변경(變更)에 따른 신치수(新値數) 및 공차계산(公差計算) -대화형식(對話形式)의 컴퓨터 프로그램개발-)

  • Hyun, Chang-Heon;Kim, Sung Joon
    • Journal of Industrial Technology
    • /
    • v.5
    • /
    • pp.65-71
    • /
    • 1985
  • In case that the datums chosen for dimension on engineering drawings are unsuitable for manufacturing and inspecting and inspection purposes and it is necessary to redimension the design from new datum. L. E. Farmer presented a theory for performing this change of datum, discussed a procedure for allocating tolerances to new dimensions and presented the procedure of change of datum as part of a computer aided design system. This paper deals with the development of the interactive computer program which is insufficiently presented without all coding list of program by L. E. Farmer.

  • PDF

A Study on the Operation Status of Rural Childcare Facilities for Better Care through Interviews with Principals (시설장 면담을 통한 농촌보육시설의 실태 및 개선방안 연구)

  • Chung, Duk-Hee
    • Journal of Agricultural Extension & Community Development
    • /
    • v.12 no.1
    • /
    • pp.97-107
    • /
    • 2005
  • The purpose of this study was to make a survey of the operation of childcare facilities in rural regions through in-depth interviews with 5 facility principals. Owing to regional disadvantages, rural childcare facilities have many problems as follows: uneven distribution of facilities, shortage of teachers, financial difficulties, unsuitable programs for rural regions, insufficient reeducation of principals and teachers, and poor operations and accessibility for handicapped or very young children. The principals proposed that many conditions might be made better as follows: evenly distributing facilities in step with needs and supply, raising the salary of teachers of rural facilities, supporting the facilities themselves side by side with supporting children, improving 'childcare fee supporting system' of the Ministry of Agriculture and Forestry, developing and spreading programs suitable for rural regions, and promoting the reeducation of principals and teachers through online programs.

  • PDF

Image Segmentation Using FSCL Neural Network (FSCL 신경망을 이용한 영상 분할)

  • 홍원학;김웅규;김남철
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.32B no.12
    • /
    • pp.1581-1590
    • /
    • 1995
  • Recently, advanced video coding techniques using segmentation technique have been actively researched as candidates for video coding of MPEG-4 standard. The conventional segmentation techniques are unsuitable for real-time process because they have sequential structure. In this paper, we propose a new image segmentation technique using competitive learning neural network for vector quantization. The proposed segmentation procedure consist of prefiltering, primary and secondary segmentation, and a small region ellimination process. Primary segmentation segments input image in detail. Secondary segmentation merges similar region using a repetitive FSCL(Frequency sensitive competive learning) neural network. In this process, it is possible to segment an image from high resolution to low resolution by adjusting the number of repetition. Finally, small regions are merged into adjacent regions. Experimental results show that the procedure described yields reconstructed images of reasonably acceptable quality at bit rates of 0. 25 - 0.3 bit/pel.

  • PDF