• 반도체디스플레이기술학회지
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• 제21권2호
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• pp.19-24
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• 2022

The purpose of this research is to determine the hardness of guide hole. A guide pin and a guide hole of SSD(Solid State Drive) tester used to mount SSD in a fixed position accurately. The guide pin and guide hole are worn by friction due to repeated operation, and the wear is concentrated on the guide hole made of weak material rather than the guide pin made of relatively strong material. Because of that reason, it is often overdesigned in the design stage because it can lose its function. If the guide hole is made soft, the manufacturing cost will decrease, but the accuracy will decrease due to wear caused by repeated friction. If the guide hole is manufactured excessively, the manufacturing process becomes complicated and the manufacturing cost increases. It is essential to design a guide hole, but since there is no standard or verified data that can be referenced, it is difficult to design. Experimental device which guides in the same way as the SSD tester is used for this research, and three types of anodizing state are experimented for different hardness. Also, weight of COK(Change over Kit) were analyzed by measuring the wear amount and state of the guide hole according to the number of repeated attachment and detachment.

• Journal of Advanced Marine Engineering and Technology
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• 제37권2호
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• pp.163-169
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• 2013

In order to make the vertical-axis cross flow wind turbine commercially feasible, a guide vane is adopted and the effect of the guide vane shape is examined in order to improve the wind turbine performance. CFD analysis on the performance and internal flow of the turbine is carried out for the wind turbine model. The result shows that when the guide nozzle is installed, almost over two times of power coefficient are achieved in comparison with the case of no guide nozzle installation. The guide nozzle acts as a role of suppressing the flow resistance at the blade passage, which is found when the guide nozzle is installed. Moreover, in this study, two kinds of the guide vane with a straight type and a curved type are adopted and compared. The curved guide vane nozzle produces higher power coefficient in comparison with that of straight guide vane nozzle.

• 한국관광식음료학회지:관광식음료경영연구
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• 제9권
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• pp.67-91
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• 1998

This study reviews the rating system of hotels and restaurants regulated by french gouvernment and compares the french guide books of worldwide reputaion : Guide rouge of Michelin and Guide France of Gault-Millau. The apparatus of gouvernment and the inspectors deciding the grades, the processes and the prior conditions needed for obtaining the adequate grades are mentioned. So it will be a help to understand the present system of hotels and restaurants in France. The publishing firms like Michelin and Gault-Millau not only encourage the trvel and F & B industry by estimating the hotels and restaurants and publishing the results, but also informe the consumer. Ultimately, the guide books would like to play an important role in improving or making better the levels of the tourism and the gastronomy. They support continuously the publishing of guide books with the qualified persons and financial aid. Especially, Michelin doesn't insert the advertisement in his publications. In publishing the guide books, it can be one of the most important points for proving his independence of hoteliers, restaurateurs and the others. The seconde point is impartial, clear and rigid inspection that doesn't admit any corruption. Now is the moment in korea to promote the tourism and the gastronomy by publishing the credible books like 「Guide rouge」 and 「Guide France」in order to present Korean attrations and epicurean foods.

• 한국공작기계학회논문집
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• 제17권1호
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• pp.7-15
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• 2008

Currently existing high-accuracy and high-speed die sets used in reciprocal press create scratches at the surface of guide posts, steel balls, and bushes due to vertical movement of balls with point-contacts between inner surface of bushes and guide posts. Consequently, accuracy of the die set and the life span of the metal mold are reduced. However, those scratches could reduce the pre-load of the steel ball. This research designed and developed a groove-type die set which improves life span of the die set by eliminating point-contacts of steel balls with guide posts. The guide post consisted of a steel-ball retainer, a steel-ball retainer stopper, a guide bush, a guide pin, a snap ring, and a spring. The steel-ball retainer has 72 holes with 8 columns of 9 holes in each column. The inner surface of the guide bush was grinded(surface roughness: $Ra\;\\;0.2{\mu}m$, accuracy: $0\;{\sim}\;-0.002mm$) after NC turning and heat treatment. Also, a line of small intermediate pocket was processed inside of the guide bush for lubrication and elimination of foreign materials. Guide grooves of steel balls were processed using a wire EDM(Electrical Discharge Machining) after heat treatment. With such a design of the guide post stated above, loads against steel balls could be dispersed greatly by the line contacts through the guide groove between the guide post and the guide bush, and the life span of the guide post could be expanded semi-permanently.

• 대한기계학회논문집A
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• 제41권6호
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• pp.543-551
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• 2017

캠퍼스를 자율적으로 주행하면서 내방객을 안내하는 안내로봇을 개발하였다. 이 로봇은 DGPS와 로봇 바퀴에 부착된 엔코더 정보를 이용하여 자신의 최적 위치를 평가하여 사전에 설정된 안내경로를 자율적으로 주행하면서 안내를 수행한다. 본 연구에서는 안내할 정보를 미리 순서대로 설정하는 기존 방법과 달리 이동 중 자신의 현재 위치를 평가하고 그 위치 주변에 안내할 정보가 있으면 그 정보를 이용하여 안내를 수행하는 위치기반 안내방법을 제안한다. 또한 안내효율을 극대화 할 수 있는 안내시나리오 구성방법을 제시한다. 개발된 안내로봇의 성능을 실제 캠퍼스 안내에 적용하여 평가하였다.

• Restorative Dentistry and Endodontics
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• 제30권3호
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• pp.170-177
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• 2005

본 연구에서는 shade guide를 이용하여 치아의 색상을 결정하는데 있어 shade guide의 형태가 미치는 영향을 평가 하기 위해 시행하였다 8가지 서로 다른 색상 code (Al, A2, Bl, B2, B3, C2, C3, D3)를 사용하는 광중합 복합레진 (Esthet-X, Dentsply, USA)을 이용하여 각 색상마다 상악 중절치 모형, 치아형 shade guide, 도넛형 shade guide, 및 회색 shield를 포함하는 shade guide를 제작하고 무작위로 기호를 부여하였다. 제작된 치아 모형을 배열하고 전남 대학교병원 치과 진료처에 근무하는 19명의 수련의와 전남대학교 치과대학 2, 3학년 학생 65명을 대상으로 회색 배경 판과 D$_{65}$ 표준광 하에서 각 치아의 색상과 일치하는 shade guide를 선택하게 하였다. 연구 결과 Bl 색상은 실험에 적용한 3가지 형태의 모든 shade guide에서 약 95%의 가장 높은 정확도를 보였으며 , 색상간 색차가 가장 적은 B2와 C2는 3가지 형태의 모든 shade guide에서 서로 비슷한 정도의 교차 선택율을 보였다. 또한 관찰자에 상관없이 치아 형태의 shade guide는 가장 높은 정확도를 보인 반면 (p < 0.05), 도넛 형태의 shade guide는 가장 낮은 정확도를 보였다 (p <0.05).

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 봄 학술발표회 논문집
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• pp.69-77
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• 1999

The stabbing guide is often used to guide an add-on pile into an existing pile in offshore jacket installation. It provides a pile alignment for a welding tie-in in static condition as well. Even stabbing guide is an essential component in pile installation, it is not considered as a permanent offshore structure. In this regard, there is not a define design guideline proposed. In API RP 2A WSD, it briefly define the design considerations of stabbing guide. The failure of stabbing guide can cause a greate economical loss and a serious impact to the project schedule. Stabbing guide design should consider many factors considering actual work conditions for both static and dynamic situations. In the paper, a design method is proposed by appling the plate theory and it is confirmed numerically with FEM modeling. The geometry of stabbing guide is assumed as a cylinder shape with various wall thickness and effective length. The various thickness, effective length and pile size are compared for stable stabbing guide design.

• International Journal of Fluid Machinery and Systems
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• 제9권3호
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• pp.256-264
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• 2016

To meet the demand of higher handling capacity, a mixed-flow submersible deep well pump was designed and tested. The main hydraulic components are made of plastics, which is free of erosion, light-weight, and environment-friendly. To simplify plastic molding process, and to improve productivity, an axial-radial guide vane was proposed. To clarify its effect on the performance, a radial guide vane and a space guide vane are developed as well. By comparison, the efficiency of the pump equipped with the axial-radial guide vane is higher than the radial guide vane and is lower than the space guide vane, and its high efficiency range is wide. The static pressure recovery of the axial guide vane is a bit lower than the space guide vane, but it is much larger than the radial guide vane. Taking the cost and molding complexity into consideration, the axial-radial guide vane is much economic, promoting its popularity for the moderate and high specific speed submersible deep well pumps.

• 한국초등과학교육학회지:초등과학교육
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• 제35권2호
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• pp.205-215
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• 2016

This study aims to investigate how elementary teachers use teachers' guide in preparation for science lessons. First, different uses of teacher's guide were analyzed. Second, how and why teachers use each section in teacher's guide were analyzed. For the study, 24 elementary school teachers were interviewed in depth. The semi-structured in-depth interviews were conducted individually and/or in small group, and additional interviews were held when necessary. The results showed that most of the teachers used teacher's guide only substitutionally, and some teachers rarely use teacher's guide, while only 3 out of 24 teachers used teacher's guide in detail. The reasons that teachers used the teacher's guide substitutionally or rarely were that most science lessons include experiments, and science textbook itself provides enough information for preparation of science lessons for 3rd and 4th grade students. The results also revealed that only few teachers read the general guideline in teacher's guide. Some sections of teacher's guide were not used. The sections that many teachers used were the aims of lesson, the learning system of the unit, background knowledge, flow of lesson, learning contents and activities. This study specifically examined the actual use of teacher's guide for lesson preparation and discussed implications for the development of more helpful teacher's guide.

• International Journal of Fluid Machinery and Systems
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• 제6권4호
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• pp.200-205
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• 2013

In order to investigate the characteristics of unsteady flow in a mixed flow pump guide vane under the small flow conditions, several indicator points in a mixed flow pump guide vane was set, the three-dimensional unsteady turbulence numerical value of the mixed flow pump which is in the whole flow field will be calculated by means of the large eddy simulation (LES), sub-grid scale model and sliding mesh technology. The experimental results suggest that the large eddy simulation can estimate the positive slope characteristic of head & capacity curve. And the calculation results show that the pressure fluctuation coefficients of the middle section in guide vane inlet will decrease firstly and then increase. In guide vane outlet, the pressure fluctuation coefficients of section will be approximately axially symmetrical distribution. The pressure fluctuation minimum of section in guide vane inlet is above the middle location of the guide vane suction surface, and the pressure fluctuation minimum of section in which located the middle and outlet of guide vane. When it is under the small flow operating condition, the eddy scale of guide vane is larger, and the pressure fluctuation of the channel in guide vane being cyclical fluctuations obviously which leads to the area of eddy expanding to the whole channel from the suction side. The middle of the guide vane suction surface of the minimum amplitude pressure fluctuation to which the vortex core of eddy scale whose direction of fluid's rotation is the same to impeller in the guide vane adhere.