• Design & Manufacturing
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• 제14권1호
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• pp.42-48
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• 2020

Titanium alloy has been in the spotlight as a core material in high-tech industries that require high strength and light weight because it has excellent strength and corrosion resistance and strength is higher than that of steel. Therefore, in various industries, existing steel products are intended to be replaced with titanium alloys. Titanium alloys can cause cutting tool breakage during cutting, and heat generated during cutting does not dissipate, accumulates in tools and workpieces, resulting in large wear and tear on thin workpieces. In addition, since titanium alloy is a metal with high chemical activity, the wear of the tool becomes more severe when the cutting speed is high, so machining of titanium bolt through cutting is very disadvantageous in terms of productivity. Therefore, the production of bolts using titanium alloys is being produced through a forging process to improve productivity and product quality. In this paper, hot forging molding analysis was performed on bolts used for fastening automobile parts using Ti-6Al-4V alloy, which is the most commonly used titanium alloy.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3307-3312
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• 2015

The papillary patterned lesion of thyroid may be challenging with many diagnostic pitfalls. Tumor stroma plays an important part in the determination of the tumor phenotype. CD34 is thought to be involved in the modulation of cell adhesion and signal transduction as CD34(+) fibrocytes are potent antigen-presenting cells. Smooth muscle actin (SMA) positivity could be diagnostic for fibroblast activation during tumorigenesis. We aimed to examine the expression of CD34 and alphaSMA in the stroma of papillary thyroid hyperplasia, papillary thyroid carcinoma and papillary tumors of uncertain malignant potential in order to elucidate their possible differential distribution and roles. A total number of 54 cases with papillary thyroid lesions were studied by routine H&E staining, CD34 and ASMA immunostaining. ASMA was not expressed in benign papillary hyperplastic lesions while it was expressed in papillary carcinoma, indicating that tumors have modulated stroma. Although the stroma was not well developed in papillary lesions with equivocal features of uncertain potentiality, CD34 was notable in such cases with higher incidence in malignant cases. So ASMA as well as CD34 could predict neoplastic behavior, pointing to the importance of the stromal role. Differences between groups suggest that the presence of CD34 + stromal cells is an early event in carcinogensis and is associated with neoplasia, however ASMA+ cells are more likely to be associated with malignant behavior and metastatic potential adding additional tools to the light microscopic picture helping in diagnosis of problematic cases with H&E.

• 한국멀티미디어학회논문지
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• 제11권9호
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• pp.1245-1257
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• 2008

이 연구에서는 기존의 클레이 애니메이션 제작 공정이 가지는 문제점을 개선하기 위해 3D 컴퓨터그래픽을 도입한 새로운 제작 공정을 제안한다. 그 핵심은 기존 공정을 바탕으로 하되 대단히 노동집약적인 캐릭터 제작 과정을, 3D 컴퓨터그래픽에 의한 디지털 캐릭터로 대체하는 것이다. 클레이 애니메이션에 등장하는 캐릭터를 3D 컴퓨터그래픽으로 구현하기 위해 클레이 캐릭터와 동일한 색상과 종류의 유성찰흙을 사용하여 폴리곤 모델링 캐릭터의 UVW 좌표 값에 맞춘 디퓨즈 맵과 디스플레이스먼트 맵을 제작하였다. 또한 파노라마 HDRI 자동 촬영 시스템을 개발하여 미니어처 세트 촬영 환경의 조명 정보를 초고해상도의 파노라마 HDRI 형식으로 제작, 이를 디지털 라이팅 소스로 사용하였다. 이 과정을 통해 대단히 사실적인 결과물을 얻음과 동시에 숙달된 작업자의 노하우에만 의존하던 스톱모션 제작 공정을 공학적 접근에 의한 자동화된 방식으로 개선할 수 있었다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 1998년도 제14회 학술발표회 논문개요집
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• pp.133-133
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• 1998

In the thin film alloy formation of the transition metals ion-beam-mixing technique forms a metastable structure which cannot be found in the arc-melted metal alloys. Sppecifically it is well known that the studies about the electronic structure of ion-beam-mixed alloys pprovide the useful information in understanding the metastable structures in the metal alloy. We studied the electronic change in the ion-beam-mixed ppt-Ct alloys by XppS and XANES. These analysis tools pprovide us information about the charge transfer in the valence band of intermetallic bonding. The multi-layered films were depposited on the SiO2 substrate by the sequential electron beam evapporation at a ppressure of less than 5$\times$10-7 Torr. These compprise of 4 ppairs of ppt and Cu layers where thicknesses of each layer were varied in order to change the alloy compposition. Ion-beam-mixing pprocess was carried out with 80 keV Ae+ ions with a dose of $1.5\times$ 1016 Ar+/cm2 at room tempperature. The core and valence level energy shift in these system were investigated by x-ray pphotoelectron sppectroscoppy(XppS) pphotoelectrons were excited by monochromatized Al K ａ(1486.6 eV) The ppass energy of the hemisppherical analyzer was 23.5 eV. Core-level binding energies were calibrated with the Fermi level edge. ppt L3-edge and Cu K-edge XANES sppectra were measured with the flourescence mode detector at the 3C1 beam line of the ppLS (ppohang light source). By using the change of White line(WL) area of the each metal sites and the core level shift we can obtain the information about the electrons pparticippating in the intermetallic bonding of the ion-beam-mixed alloys.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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• pp.28-30
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• 2005

Because of high population diversity in soil microbial communities, it is difficult to accurately assess the capability of biodegradation of toxicant by microbes in soil and sediment. Identifying biodegradative microorganisms is an important step in designing and analyzing soil bioremediation. To remove non-important noise information, it is necessary to selectively enrich genomes of biodegradative microorganisms fromnon-biodegradative populations. For this purpose, a stable isotope probing (SIP) technique was applied in selectively harvesting the genomes of biphenyl-utilizing bacteria from soil microbial communities. Since many biphenyl-using microorganisms are responsible for aerobic PCB degradation In soil and sediments, biphenyl-utilizing bacteria were chosen as the target organisms. In soil microcosms, 13C-biphenyl was added as a selective carbon source for biphenyl users, According to $13C-CO_2$ analysis by GC-MS, 13C-biphenyl mineralization was detected after a 7-day of incubation. The heavy portion of DNA(13C-DNA) was separated from the light portion of DNA (12C-DNA) using equilibrium density gradient ultracentrifuge. Bacterial community structure in the 13C-DNAsample was analyzed by t-RFLP (terminal restriction fragment length polymorphism) method. The t-RFLP result demonstates that the use of SIP efficiently and selectively enriched the genomes of biphenyl degrading bacteria from non-degradative microbes. Furthermore, the bacterial diversity of biphenyl degrading populations was small enough for environmental genomes tools (metagenomics and DNA microarrays) to be used to detect functional (biphenyl degradation) genes from soil microbial communities, which may provide a significant progress in assessing microbial capability of PCB bioremediation in soil and groundwater.

• 한국자동차공학회논문집
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• 제16권5호
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• pp.1-7
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• 2008

A study of new materials that are light-weight, high in strength has become vital to the machinery of auto industries. But then, there are a lot of problems with developing such materials that require expensive tools, and a great deal of time and effort. Therefore, the improvement of fatigue strength and fatigue life are mainly focused on by adopting residual stress. And Influence of corrosive condition for corrosion fatigue crack was investigated, after immersing in 3.5%NaCl, $10%HNO_3$+3.5%HF, $6%FeCl_3$. The immersion period was performed for 365days. The compressive residual stress was imposed on the surface according to each shot velocity based on shot peening, which is the method of improving fatigue life and strength. Fatigue life shows more improvement in the shot peened material than in the un peened material in corrosion conditions. The threshold stress intensity factor range was decreased in corrosion environments over ambient. Compressive residual stress of surface on the Shot-peen processed operate resistance force of fatigue crack propagation. The fatigue crack growth rate of the Shot-peened material was lower than that of the un peened material. Also m, fatigue crack growth exponent and number of cycle of the shot peened material was higher than that of the un peened material. That is concluded from effect of da/dN.

• 한국식품조리과학회지
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• 제9권2호
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• pp.109-115
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• 1993

This study was attempted to investigate the current status of industry food service management in Chonbuk province. The survey for the analysis was conducted through the questionaires to dietitian. The following results are to be noted. 1. Only one dietitian was employed regardless of feeding numbers and feeding times, and the average number of cooks comes to 5∼6 persons. Among 51 food service places for the study, 84.3% provided more than two meals a day. Feeding number were 200∼1000 people per one meal (64.7%) and feeding cost amounts to 700∼1000 won per meal per one person. 2. The food preferences and budget were primary considerations in menu planning. The type of menus was a non-selective menu with a seven-day cycle (83.7%). Most of dietitian (94.1%) had control of food purchasing, receiving and checking procedure and prefered placing orders by phone (94.5%) through the purveyors (86.4%). 3. In many food service places (70.5%), the mass food preparation was controlled of cooking method and standardized recipes were not undertaken by management Also, the food quality control such as flavor, texture, appearance and temperature was not fully established in food service system. 4. They used the method of manual dish washing operations (88%) and about 71.4% of them are dependent on boiling method of ultrabiolet light for disinfection of kitchen utensils. 5. The performance rates of dietitian management responsibility showed as nutritional management 100%, working management 72.4%, sanitary management 85.6%, personnel management 64.5% and nutrition education 40.7%, but they did not perform the objective and systematic their own responsibility as specialized dietitian because only few dietitian used basic check list and management tools. In addition, dietitian (21.6%) worked beyond their field. In the result, only 54.9% dietitian have satisfied their own occupation and most of them emphasized on practical working in educational curriculums.

• International Journal of Knowledge Content Development & Technology
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• 제4권1호
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• pp.23-37
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• 2014

The Trust and Authority in Scholarly Communications in the Light of the Digital Transition research project1) was a study which investigated the behaviours and attitudes of academic researchers as producers and consumers of scholarly information resources in respect to how they determine authority and trustworthiness. The research questions for the study arose out of CIBER's studies of the virtual scholar. This paper focuses on elements of this study, mainly an analysis of a scholarly publisher's usage logs, which was undertaken at the start of the project in order to build an evidence base, which would help calibrate the main methodological tools used by the project: interviews and questionnaire. The specific purpose of the log study was to identify and assess the digital usage behaviours that potentially raise trustworthiness and authority questions. Results from the self-report part of the study were additionally used to explain the logs. The main findings were that: 1) logs provide a good indicator of use and information seeking behaviour, albeit in respect to just a part of the information seeking journey; 2) the 'lite' form of information seeking behaviour observed in the logs is a sign of users trying to make their mind up in the face of a tsunami of information as to what is relevant and to be trusted; 3) Google and Google Scholar are the discovery platforms of choice for academic researchers, which partly points to the fact that they are influenced in what they use and read by ease of access; 4) usage is not a suitable proxy for quality. The paper also provides contextual data from CIBER's previous studies.

• Nuclear Engineering and Technology
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• 제47권1호
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• pp.26-32
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• 2015

During the course of a severe accident in a light water nuclear reactor, large amounts of hydrogen can be generated and released into the containment during reactor core degradation. Additional burnable gases [hydrogen ($H_2$) and carbon monoxide (CO)] may be released into the containment in the corium/concrete interaction. This could subsequently raise a combustion hazard. As the Fukushima accidents revealed, hydrogen combustion can cause high pressure spikes that could challenge the reactor buildings and lead to failure of the surrounding buildings. To prevent the gas explosion hazard, most mitigation strategies adopted by European countries are based on the implementation of passive autocatalytic recombiners (PARs). Studies of representative accident sequences indicate that, despite the installation of PARs, it is difficult to prevent at all times and locations, the formation of a combustible mixture that potentially leads to local flame acceleration. Complementary research and development (R&D) projects were recently launched to understand better the phenomena associated with the combustion hazard and to address the issues highlighted after the Fukushima Daiichi events such as explosion hazard in the venting system and the potential flammable mixture migration into spaces beyond the primary containment. The expected results will be used to improve the modeling tools and methodology for hydrogen risk assessment and severe accident management guidelines. The present paper aims to present the methodology adopted by Institut de Radioprotection et de $S{\hat{u}}ret{\acute{e}}$ $Nucl{\acute{e}}aire$ to assess hydrogen risk in nuclear power plants, in particular French nuclear power plants, the open issues, and the ongoing R&D programs related to hydrogen distribution, mitigation, and combustion.

• 한국식품영양과학회지
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• 제13권1호
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• pp.1-8
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• 1984

식품이 가지고 있는 고유한 색깔은 소비자의 기호성 또는 영양학적 가치의 지표가 될 수 있으며 가공 및 저장처리조건에 따른 식품의 중요한 인자로 작용 할 수 있다. 따라서, 본 실험에서는 식물성 식품재료의 품종, 성숙도, 성장조건(온도, 수분. 제조공정 별)에 따른 Surface color change를 color & color difference meter와 Munsell disc 색도계(色度計)로 X, Y, Z값을 측정하고 공식에 의하여 Y(one of variation in luminous reflectance), x, y(chromaticity)를 구하여 이로부터 작성한 색도좌표상에서 식품의 색상(hue) 및 강도(chroma)를 산출하여 식품의 색도 변화를 검토하였다. 이와 같이 color & color difference meter와 같은 reflectometer를 이용하여 얻은 data를 중심으로 각각의 chromaticity diagram을 작성, 식품의 저장 및 가공처리별 색도변화를 측정하여 이것을 토대로 식품 품질의 특성을 판정할 수 있는 좋은 기초자료를 얻을 수 있었다.