• 제목/요약/키워드: Leading Journal

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In Vivo Transfer of Foreign DNA into Primordial Germ Cells (PGCs) of Chicken Embryos

  • Eguma, K.;Soh, T.;Hattori, M.;Fujihara, N.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권4호
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    • pp.520-524
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    • 1999
  • The present experiments were designed to examine whether exogenous DNA injected into the germinal crescent region (GCR) of early stage of developing embryos, which is considered to be the main place from which PGCs originate, can be transferred to recipient chicken embryos. In this experiment, Miw Z (DNA) dissolved in the transfection reagent (TR: Boehringer, Germany) was introduced into the GCR of donor embryos at stage 3-5 or 9-11, followed by continued incubation until the stage 13-15 of embryonic development. The PGCs collected from the embryonic blood vessels were examined for the incorporation of the injected DNA into the PGCs by the methods of X-gal staining and PCR analysis. As the results, the foreign DNA was successfully incorporated into the PGCS, leading to their transfer to the gonadal tissues. The present results, therefore, suggest that the early stage (3-5 or 9-11) of chicken embryonic development would be more successful than stage 13-15 in transferring exogenous genes to the recipient embryos, leading to the possibility of producing transgenic chicken medianting the PGCS.

CONTROL OF SWINE DISEASE - Review-

  • Furuuchi, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제5권3호
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    • pp.411-418
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    • 1992
  • Recently, onset of bacterial disease, especially infiltration of chronic respiratory diseases have been increasing at high rate. The main cause of these diseases are originated from inappropriate sanitary management and slow progress in introducing system and herd free system, which are the base of productivity improvement in bigger pig management, Methods for the prevention and removal of these diseases, are divided into four categories. The first category includes prevention and removal of infectious diseases by organizing strict animal quarantine, enforcing vaccination, and legal regulation and disposal at the time of outbreak. The second category includes improvement of production systems. This purpose can be achieved by discontinuing the open herd system, which brings on the invasion of foreign pathogens and replacing the system by the closed type of farm. To Continue eradication process step-wisely by performing the all-in all-out system at every pig pen or herd level is also effective for this purpose. The third category includes introduction of herd free system can be achieved by repopulating conventional pigs with SPF pigs. If these means are unrealizable from economic or technical viewpoint, medicated early weaning system is perfomed. This system consists of disinfection of pigsty at pre-postpartum stage, application of drugs to pregnant sows and newborn piglets in accordance with the medication program, and early weaning and rearing of newborn piglets in isolation. The fourth category is sanital leading by veterinarians, aimed to eliminating incentives for diseases through diagnoses. Their main activities include periodical monitoring and improvement leading on each responsible subject.

A Study on Thai Seaweed Market Segmentation by Purchasing Attributes (구매속성에 의한 태국 김 시장세분화에 관한 연구)

  • Jang, Young-Soo;Kim, Ji-Ung
    • The Journal of Fisheries Business Administration
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    • 제48권3호
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    • pp.1-14
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    • 2017
  • The aim of this study is to examine profiles of consumers in Thai seaweed market segments. A total of 321 consumers were surveyed in bangkok, thailand. The multiple regression analysis performed indicates that consumer preference toward seaweed snack is significantly influenced by seaweed consumption frequency. The cluster analysis performed indicates that there are three segments based on consumer purchasing attributes toward seaweed snack : leading type, pursuing type, beginner type. The results show that there are consumer segment with different purchasing attributes level and seaweed preference. in this study Thai seaweed market's biggest consumer is leading type consumer(n=40.8%) that have high level of purchasing attributes toward seaweed snack when compared to other segments. pursuing type segment(n=27.4%) consists of consumers who have low level of purchasing attributes but have high consumption frequency. beginner type segment(n=31.8%) consists of consumers who rarely eat seaweed snack and have high price sensitivity. This study can inform Thai seaweed consumer's behavior and effective segment market strategies and target consumer based on purchasing behavior toward seaweed snack.

Users' Status Quo Bias in the Mobile Application Context : From the Myopic Loss Aversion Perspective (근시안적 손실회피 관점에서 본 모바일 애플리케이션 사용자의 현상유지 편향에 관한 연구)

  • Park, Sang-Cheol
    • The Journal of Information Systems
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    • 제24권2호
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    • pp.189-208
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    • 2015
  • Purpose While individuals have unique abilities for planned behavior, they also often act irrationally. In this study, we draw on myopic loss aversion perspective as a meta-theoretical lens to explain why mobile applications users have inertia from updating their applications, ultimately leading them to use current version of applications. Design/methodology/approach Based on a survey of 219 users, this study conducts its research model using partial least square analysis and also demonstrates that both subconscious triggers (habit and anxiety) of system 1 thinking and conscious triggers (sunk cost and transition cost) of system 2 thinking promotes user's inertia, thus leading to the willness to continue use current versions. Findings By grounding the research model in the combination of both status quo bias and dual information processing theory from the behavioral economics, this study provide an alternative theoretical lens to describe why mobile users hesitate to update their applications. The results of this research show that all triggers have significant impacts on inertia. This study also found that the relationship between inertia and willingness to continue to use current version was positively significant.

V2X Technology Trends for Next-Generation Mobility

  • Kim, Young-Hak
    • International Journal of Internet, Broadcasting and Communication
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    • 제12권1호
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    • pp.7-13
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    • 2020
  • We describes V2X technology, a connectivity-based recognition technology that is attracting attention as a key technology for implementing autonomous driving technology, and autonomous communication modules that implement ADAS technology, a sensor-based recognition technology. It also explains the trends in V2X technology standardization centered on IEEE 802.11p, which is a WAVE technology standard based on Wi-Fi/DSRC. Finally, we will discuss the market growth trend of V2X communication modules in the United States, the leading V2X technology module, and the development of technology development trends of major domestic and international companies that are leading the global technology market related to V2X communication modules. V2X and ADAS technologies will be the biggest influence on automotive purchasing decisions. In recent years, V2I mandates have been promoted beyond V2V, mainly in developed countries such as the United States. The related industry needs to focus on the development of information transmission network technology that can support high frequency high efficiency(transmission rate) and sophisticated positioning accuracy beyond conventional vehicle communication.

A Study on Clothing Attitude of Chinese Students in Korea - Focused on Gender, Socio-economic Level and Resident Period - (한국내 중국인 유학생의 의복태도 연구 - 성별, 사회경제적 수준별, 한국거주기간별 -)

  • Yu, Ji-Hun
    • Journal of the Korea Fashion and Costume Design Association
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    • 제11권2호
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    • pp.153-168
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    • 2009
  • The purpose of this study was to identify the clothing attitude of Chinese students in korea according to gender, socio-economic level and resident period. The survey was conducted from October 30th to November 25th 2008, and 267 questionnaires were used for the analysis. Data were analyzed by factor analysis, T-test, ANOVA, Duncan's Multiple Range Test with SPSS 12.0. The results were as follows: 1. Most of Chinese students were middle-class Han race and they have been staying in Korea for 3 years. 2. Fashion leadership was classified as Innovation and Opinion leading factor; conformity as Nonconformity, Identification, and Norm consciousness; pursuit benefit as Practicality, Economy, and Aesthetic. 3. The Innovation factor was highly marked in female student group, the Opinion leading factor was higher in high-class group, and the pursuit benefit factor was significantly different between less than three years group and over three years group who have been in Korea. 4. We need to recommend best-design clothes for high-class Chinese female students who have been in Korea for over three years, and low-price clothes for less than 3 years.

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A Behavior of the Diffuser Rotating Stall in a Low Specific Speed Mixed-Flow Pump

  • Miyabe, Masahiro;Furukawa, Akinori;Maeda, Hideaki;Umeki, Isamu;Jittani, Yoshinori
    • International Journal of Fluid Machinery and Systems
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    • 제2권1호
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    • pp.31-39
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    • 2009
  • The flow instability in a low specific speed mixed-flow pump, having a positive slope of head-flow characteristics was investigated. Based on the static pressure measurements, it was found that a rotating stall in the vaned diffuser occurs at about 65% flow rate of best efficiency point (BEP). A dynamic Particle Image Velocimetry (DPIV) measurement and the numerical simulations were conducted in order to investigate the flow fields. As a result, the diffuser rotating stall was simulated even by Computational Fluid Dynamics (CFD) and the calculated periodic flow patterns agree well with the measured ones by DPIV. It is clarified that a periodical large scaled backflow, generated at the leading edge of the suction surface of the diffuser vane, causes the instability. Furthermore, the growth of the strong vortex at the leading edge of the diffuser vane induces the strong backflow from the diffuser outlet to the inlet. The scale of one stall cell is covered over four-passages in total thirteen vane-passages.

Survey for Technology Forecasting for Crop Production using Delphi Method (경종작물분야의 델파이 기술예측조사)

  • Young-Am Chae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • 제49권3호
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    • pp.261-270
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    • 2004
  • The study was designed to forecast and derive future core technologies using Delphi method in Korea agriculture. Based on the technologies, agriculture in Korea will be expected to improve as a core and strategic industry producing high value added in 21 century. Questions were given to specialists by each technology in order to survey importance, realization time, level of R&D in Korea and the leading country, leading group of R&D, effective policy, etc. for each technology. The survey for Delphi was confined to the specialists in the area of crop production. The 44 core technologies were derived and 39 specialists answered the survey.

A Study of an Airfoil for Optimal Aerodynamic Performance of Flapping Motion (Flapping운동의 최적공력성능을 위한 익형 연구)

  • Lee J. S.;Kim C.;Rho O. H.
    • Journal of computational fluids engineering
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    • 제8권2호
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    • pp.24-32
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    • 2003
  • In this work, we propose a new idea of flapping airfoil design for optimal aerodynamic performance from detailed computational investigations of flow physics. Generally, flapping motion which is combined with pitching and plunging motion of airfoil, leads to complex flow features such as leading edge separation and vortex street. As it is well known, the mechanism of thrust generation of flapping airfoil is based on inverse Karman-vortex street. This vortex street induces jet-like flow field at the rear region of trailing edge and then generates thrust. The leading edge separation vortex can also play an important role with its aerodynamic performances. The flapping airfoil introduces an alternative propulsive way instead of the current inefficient propulsive system such as a propeller in the low Reynolds number flow. Thrust coefficient and propulsive efficiency are the two major parameters in the design of flapping airfoil as propulsive system. Through numerous computations, we found the specific physical flow phenomenon which governed the aerodynamic characteristics in flapping airfoil. Based on this physical insight, we could come up with a new kind of airfoil of tadpole-shaped and more enhanced aerodynamic performance.

A Study on the Spray Atomization Characteristics of a Multi-Hole Diesel Nozzle using PDPA System (PDPA계측에 의한 다공 디젤 노즐의 분무 미립화 특성에 관한 연구)

  • Lee, J.K.;Oh, J.H.;Kang, S.J.;Rho, B.J.
    • Journal of ILASS-Korea
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    • 제4권1호
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    • pp.45-54
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    • 1999
  • The spray characteristics of a direct injection multi-hole diesel nozzle having the 2-spring nozzle holder were investigated by using the image processing system and a PDPA(phase Bowler particle analyzer) system. The spray tip penetration, the spray angle, and the droplet diameter and velocity with the variation of the pump speed, injection quantity were measured. From, the experiments, we know that there are small droplets which are not to be detected with spray image around the leading edge of the spray. In order to represent the mean characteristics of the intermittent spray very well, it is very important to set the time windows accurately. From the measurements along the axis of the spray, close to the nozzle, the initially injected droplets are overtaken by droplets that follow them. And also there are the maximum axial mean velocity and SMD at the following part of the leading edge of the spray.

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