• Nuclear Engineering and Technology
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• v.45 no.5
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• pp.613-624
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• 2013

Multi-dimensional two-phase phenomena occur in many industrial applications, particularly in a nuclear reactor during steady operation or a transient period. Appropriate modeling of complicated behavior induced by a multi-dimensional flow is important for the reactor safety analysis results. SPACE, a safety analysis code for thermal hydraulic systems which is currently being developed, was designed to have the capacity of multi-dimensional two-phase thermo-dynamic phenomena induced in the various phases of a nuclear system. To validate the performance of SPACE, a two-dimensional two-phase flow test was performed with slab geometry of the test section having a scale of $1.43m{\times}1.43m{\times}0.11m$. The test section has three inlet and three outlet nozzles on the bottom and top gap walls, respectively, and two outlet nozzles installed directly on the surface of the slab. Various kinds of two-dimensional air/water flows were simulated by selecting combinations of the inlet and outlet nozzles. In this study, two-dimensional two-phase void fraction profiles were quantified by measuring the local gap impedance at 225 points. The flow conditions cover various flow regimes by controlling the flow rate at the inlet boundary. For each selected inlet and outlet nozzle combination, the water flow rate ranged from 2 to 20 kg/s, and the air flow rate ranged from 2.0 to 20 g/s, which corresponds to 0.4 to 4 m/s and 0.2 to 2.3 m/s of the superficial liquid and gas velocities based on the inlet port area, respectively.

• Parasites, Hosts and Diseases
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• v.57 no.1
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• pp.33-38
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• 2019

Trichomoniasis is a common sexually transmitted infection caused by Trichomonas vaginalis, which actually does not exist a vaccine for control or prevention. Thus, the identification of new and potent immunogens in T. vaginalis, which can contribute to the development of a vaccine against this parasite, is necessary. Therefore, the aim of this work was to evaluate the potential of a recombinant Transient Receptor Potential-like channel of T. vaginalis (TvTRPV), as a promising immunogen in BALB/c mice. First, TvTRPV was cloned and expressed as a recombinant protein in Escherichia coli BL21 cells and purified by nickel affinity. Next, BALB/c mice were immunized and the antibody levels in mice serum and cytokines from the supernatant of macrophages and from co-culture systems were evaluated. Recombinant TvTRPV triggered high levels of specific total IgG in sera from the immunized mice. Also, a statistically significant increase of cytokines: $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$ after stimulation with the corresponding antigens in vitro, was identified. Moreover, co-cultures using $CD4^+$ T cells from immunized mice were able to identify higher levels of IL-10 and $IFN-{\gamma}$. These results were useful to validate the immunogenicity of TvTRPV in BALB/c mice, where IL-10-$IFN-{\gamma}$-secreting cells could play a role in infection control, supporting the potential of TvTRPV as a promising target for vaccine against T. vaginalis.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.12
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• pp.1852-1862
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• 2018

Objective: The purpose of this study was to investigate a single step genome-wide association study (ssGWAS) for identifying genomic regions affecting reproductive traits in Landrace and Large White pigs. Methods: The traits included the number of pigs weaned per sow per year (PWSY), the number of litters per sow per year (LSY), pigs weaned per litters (PWL), born alive per litters (BAL), non-productive day (NPD) and wean to conception interval per litters (W2CL). A total of 321 animals (140 Landrace and 181 Large White pigs) were genotyped with the Illumina Porcine SNP 60k BeadChip, containing 61,177 single nucleotide polymorphisms (SNPs), while multiple traits single-step genomic BLUP method was used to calculate variances of 5 SNP windows for 11,048 Landrace and 13,985 Large White data records. Results: The outcome of ssGWAS on the reproductive traits identified twenty-five and twenty-two SNPs associated with reproductive traits in Landrace and Large White, respectively. Three known genes were identified to be candidate genes in Landrace pigs including retinol binding protein 7, and ubiquitination factor E4B genes for PWL, BAL, W2CL, and PWSY and one gene, solute carrier organic anion transporter family member 6A1, for LSY and NPD. Meanwhile, five genes were identified to be candidate genes in Large White, two of which, aldehyde dehydrogenase 1 family member A3 and leucine rich repeat kinase 1, associated with all of six reproduction traits and three genes; retrotransposon Gag like 4, transient receptor potential cation channel subfamily C member 5, and LHFPL tetraspan subfamily member 1 for five traits except W2CL. Conclusion: The genomic regions identified in this study provided a start-up point for marker assisted selection and estimating genomic breeding values for improving reproductive traits in commercial pig populations.

• Journal of Oral Medicine and Pain
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• v.45 no.4
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• pp.97-109
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• 2020

Purpose: Cervicogenic headache (CGH) is pain referred to the head/ face from the structures in vicinity of upper cervical spinal nerves via trigeminocervical pathway. Ponticulus Posticus (PP) and Elongated Styloid Process (ESP) are anatomical structures that cause compression of vasculature present around upper cervical nerve plexus. Recently, computational fluid dynamics (CFD) has shown to play an essential role in identification of these high-pressure zones in the brain. The aim of this research is to study the association of ESP and PP in patients with CGH and to develop a hypothesis by CFD to analyse vertebrobasilar insufficiency as a contributing factor in occurrence of CGH. Methods: Retrospective analysis of 4500 full skull CBCT scans was done for the presence of partial or complete PP and length of Styloid Process (SP). Research was divided into two phases; In first Preliminary Phase, 150 scans that showed the presence of PP and ESP were analysed, and only 134 patients gave consent to fill the questionnaire containing 96 question items pertaining to symptoms associated with CGH. In the second phase, simulation of Vertebral and Carotid Artery was done using Fluent 14.5 Software and by CFD, pressure distribution on arteries was obtained that helped to identify high pressure regions. Results: Both PP and ESP showed a statistically significant association with CGH (p<0.001). By CFD analysis, both steady and transient phases of simulation showed drop in pressure due to constriction of internal carotid and vertebral artery by ESP and PP respectively and were found to decrease the volume of blood reaching the brain, 0.12 /0.13 mL and 0.06 mL respectively. Conclusions: Our analysis proves ESP and PP as contributing factors towards CGH. Hence for proper diagnosis and management of headache disorders, clinicians should have adequate knowledge about these anatomical structures and their resulting clinical symptoms.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.369-375
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• 2004

Gas turbine engine simulation in terms of transient, steady state performance and operational characteristics is complex work at the various engineering functions of aero engine manufacturers. Especially, efficiency of control system design and development in terms of cost, development period and technical relevance implies controlling diverse simulation and identification activities. The previous engine simulation has been accomplished within a limited analysis area such as fan, compressor, combustor, turbine, controller, etc. and this has resulted in improper engine performance and control characteristics because of limited interaction between analysis areas. In this paper, we propose a new simulation methodology for gas turbine engine performance analysis as well as its digital controller to solve difficulties as mentioned above. The novel method has particularities of (ⅰ) resulting in the integrated control simulation using almost every component/module analysis, (ⅱ) providing automated math model generation process of engine itself, various engine subsystems and control compensators/regulators, (ⅲ) presenting total sophisticated output results and easy understandable graphic display for a final user. We call this simulation system GT3GS (Gas Turbine 3D Graphic Simulator). GT3GS was built on both software and hardware technology for total simulation capable of high calculation flexibility as well as interface with real engine controller. All components in the simulator were implemented using COTS (Commercial Off the Shelf) modules. In addition, described here includes GT3GS main features and future works for better gas turbine engine simulation.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06c
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• pp.274-276
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• 2006

e-seal은 RFID(Radio Frequency IDentification) 기술을 사용하여 원격에서 자동으로 봉인상태를 확인할 수 있는 컨테이너 봉인 장치를 말한다. RFID의 특징상 반도체 칩에 기록된 정보를 제 삼자가 쉽게 판독 및 변조할 수 있다는 취약점으로 인하여 활성화되지 못하고 있는 실정이다. ISO에서는 RFID의 취약점을 보안하기 위한 표준작업(ISO 18185)을 진행 중이다. 이 중, ISO 18185-4는 e-seal에 저장되는 자료나 리더와의 RF통신에서 데이터 보호를 위한 표준이다. 이와 관련된 연구로는 인증 프로토콜과 ISO 18185-4를 위한 보고서로 제출된 보안 프로토콜이 있다. 제안된 e-seal 보안 프로토콜을 적용하기 위해서는 e-seal과 리더 간의 데이터를 암/복호화할 키가 필요하지만, 키 서버를 통해 전달받은 마스터 키를 데이터 암/복호화 키로 바로 사용하는 것은 보안 상의 문제점을 야기할 수 있기 때문에 PRF(Pseudo Random Function)을 이용하여 마스터 키로부터 MTK(Mutual Transient Key)를 유도하고, MTK를 암/복호화 키로 사용해야 한다. 기존의 PRF는 일방향 해시 함수(MD5, SHA 등)를 기반으로 하는 HMAC[2. 3]을 일반적으로 사용하였다. 그러나 일방향 해시 함수는 e-seal과 같은 제한된 자원을 갖는 환경에 적합하지 않다. 따라서, 본 논문에서는 e-seal 보안 프로토콜을 위한 효율적인 PRF을 제안한다. 기존의 일방향 해시 함수 기반이 아닌 블록 암호화 알고리즘을 기반으로 하는 MAC을 이용하여 PRF을 보다 효율적으로 구현하였고, 블록 암호화 알고리즘은 AES를 선택 합성체 $GF((2^4)^2)$을 통해 하드웨어 모듈을 최적화 하였다. AES를 기반으로 하는 MAC은 HMAC에 비해 면적 및 처리율에서 뛰어난 결과를 보여주었다.<0.01).이상의 연구 결과, cook-chill생산 시 녹차 추출물의 첨가가 미생물적 품질유지에 효과가 있다고 사료되는 바 본 연구결과를 기초로 급식소에서 음식 생산 시 녹차 추출물 및 천연 항균성 물질 첨가에 따른 미생물적 품질 및 관능적 품질검사를 통한 레시피 개발에 관한 지속적인 연구가 수행되어야 하겠다.다.다리다보니 점심시간을 활용할 수 없게 되는 문제점에 대한 재검토가 필요하다. 따라서 차후 학교급식의 안전성 확보를 위한 급식환경 개선의 일환으로 식당공간 확보 시 신속한 시간 내에 급식이 가능하도록 넓은 공간과 쾌적한 환경의 식당 조성에 대해 관심을 기울여야 할 것으로 사료된다. 이상 여부를 반영하는 임상증상의 빈도가 높은 청소년기 남녀 중학생의 경우 아침과 저녁의 결식빈도 및 외식과 간식의 빈도가 높았고, 아침식사의 질과 체형만족도가 낮은 것으로 나타나 청소년의 건강과 식습관 및 체형만족도가 상호 관련성이 높은 것으로 나타났다. 따라서 본 연구 결과는 성장기 청소년의 건강 유지를 위하여 바람직한 식습관의 중요성을 재인식할 수 있었으며, 올바른 식습관 확립을 위한 영양교육의 중요성이 재확인되었다.경제적일 것으로 판단된다.er 90 % of good relative dynamic modulus of elasticity due to fineness of formation caused by the increase of the unit powder content and the improvement of flowability, without regard to the replacement of crushed stone fines. Therefore, it can be said that the usage of crushed stone fines can control the strength of super flowing concrete by replacement and re

• Management & Information Systems Review
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• v.31 no.4
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• pp.559-592
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• 2012

In spite of the transitional changes in the shoe industry in Busan area, regular academic studies on the management plan to improve the practical competitiveness of footwear industry focused in the materials, bio-dynamics, components, and designs, etc. in the engineering viewpoint are very rare. Many reports of policies were published from late 190's to 2000's but they were limited to the identification of practical situations and the measures for strategic alternatives and were not developed to be the academic studies to improve the competitiveness in terms of management control. It is intended to seek for the measures to be reviewed as the alternatives to improve the self-competitiveness of footwear companies by approaching the problems limited to such specific area in the viewpoint of management control. The core of this study is to provide the alternative plans for expansion of the industrial foundation by seeking for the measures to improve competitiveness with application of knowledge management as an alternative for improvement of not transient but sustainable industrial competitiveness, in order to help the export of shoes from Busan area which has been rapidly increased since the Korea-USA FTA and Korea-EU FTA. In such viewpoint, in the study, a questionnaire survey was performed related with the issues of Busan's footwear industry and the plan to implement knowledge management was discussed for improvement of the competitiveness of footwear industry based on the result of such questionnaire survey. As most of studies and directions have been focused in functional shoes, designs, materials, and components, etc., which are related with the properties of human dynamics, as the alternatives for improvement of the footwear industry of Busan area and did not suggest the measures to make basic changes in the management of companies, the implementation of knowledge management was emphasized in order to seek for the direction of such plan. The purpose of this study is to suggest an alternative for construction of industrial eco-system for high added value by seeking for the probability of knowledge management for conversion of footwear industry into knowledge industry. In order to accomplish the effect of increased export as the result of FTA, current management method of footwear companies is limited and the effect of FTA should be maximized by improving the competitiveness with implementation of knowledge management methods. Settlement of such knowledge management will act as the momentum to improve the competitiveness of footwear companies and, in a long-term viewpoint, will be able to maximize the improvement of knowledge industry and creation of job opportunities.