• Journal of Periodontal and Implant Science
• /
• 제52권5호
• /
• pp.411-421
• /
• 2022

Purpose: In this study, we aimed to evaluate the degree of heat generation when a novel drill design with an irrigation slot was used with metal sleeve-free (MF) and metal sleeve-incorporated (MI) surgical guides in an environment similar to that of the actual oral cavity. Methods: A typodont with a missing mandibular right first molar and 21 bovine rib blocks were used. Three-dimensional-printed MF and MI surgical guides, designed for the placement of internal tapered implant fixtures, were used with slot and non-slot drills. The following groups were compared: group 1, MI surgical guide with slot drill; group 2, MI surgical guide with a non-slot drill; and group 3, MF surgical guide with a slot drill. A constant-temperature water bath at 36℃ was used. The drilling was performed in 6 stages, and the initial, highest, and lowest temperatures of the cortical bone were measured at each stage using a non-contact infrared thermometer. Results: There were no temperature increases above the initial temperature in any drilling procedure. The only significant difference between the non-slot and slot groups was observed with the use of the first drill in the MI group, with a higher temperature in the non-slot group (P=0.012). When the heat generation during the first and the second drilling was compared in the non-slot group, the heat generation during the first drilling was significantly higher (P<0.001), and there was no significant difference in heat generation between the drills in the slot group. Conclusions: Within the limitations of this study, implant-site preparation with the surgical guide showed no critical increase in the temperature of the cortical bone, regardless of whether there was a slot in the drill. In particular, the slotted drill had a cooling effect during the initial drilling.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 추계학술대회
• /
• pp.114-117
• /
• 2004

The purpose of this study is to investigate geometric effect on the contact stress at a lip seal. The geometries of interest were angle, thickness of lip seal and width of contact surface. The contact stress was calculated by using a coupled thermo-mechanical analysis method. The friction thermal load between lip seal and sleeve was adopted to design load. Based on the FEA results, design variables for controlling the maximum contact stress at the lip seal were identified.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1990년도 하계학술대회 논문집
• /
• pp.308-311
• /
• 1990

This paper presents the insulation design of 345kV OF cable normal joint which is essential to construction of underground transmission system. The insulation designs of stress relief cone, pencilling and sleeve were proposed in this paper, and the final insulation design was decided by the results of the electric field and thermal analysis using FEM. It is shown that the designed normal using proves the effect when the developing test is carried out to construct 345kV OF cable if the domestic underground transmission system.

• 한국감성과학회:학술대회논문집
• /
• 한국감성과학회 2008년도 추계학술대회
• /
• pp.118-121
• /
• 2008

The purpose of this study was to evaluate the wearing sensation of T-shirts made with silver combination yarns. The four different single jersey fabrics were knitted to make long sleeve T-shirts: cotton(C), cotton/silver(CS), polyester(P), and polyester/silver(PS). The four kinds of T-shirts were evaluated by six healthy male subjects in a climatic chamber($25^{\circ}C$, 65%RH, 0.5m/sec). The results were as follows. Thermal and fatigue sensation of wearing CS was best. It was found that overall subjective sensation was improved by using silver yarn with cotton for health knitwear.

• 한국원자력학회:학술대회논문집
• /
• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
• /
• pp.659-665
• /
• 1995

액체금속로는 기존의 가압경수로와는 달리 55$0^{\circ}C$ 정도의 고온에서 운전이 되므로 고온 열응력이 중요한 문제로 대두되며 따라서 고은에서의 크립(Creep) 변형, 반복되는 기동과 정지 등으로 인한 되풀이 소성변형, 라체팅(Ratchetting), 크립과 소성의 상호작용 및 크립과 피로의 상호작용 등의 평가에 대한 기술 확립과 고온구조물에 대한 우리의 독자적인 설계방법을 개발하는 것이 필요하다 본 연구에서는 범용 유한요소해석코드인 ABAQUS의 축대칭 요소를 이용해서 액체 금속로 원자로용기와 이에 부착된 열소매(Thermal sleeve)를 Y-형태의 구조물로 모델링하여 반복되는 열천이하중에 대한 비탄성 구조해석을 수행하고 크립효과에 대한 영향을 분석하였다. 해석결과 액체금속로와 같은 고온구조물에 대하여 반복 열천이 하중과 고온 지속시간이 유발하는 크립효과가 크게 나타남을 알 수 있었다.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 B
• /
• pp.800-802
• /
• 2004

When an accident is happen due to using a bad Wire Compressor, some public resentments are caused and It cause lawsuit for we. In case, we will undergo a colossal financial loss. in addition to, Guide to improve quality of operation by using the number of times of pressing and pressing pressure with cooperative private enterprise. And because of needs for Thermal, Electrical and Chemical factor analysis of connection point of sleeve, expect to try improving problems of wire presser whole our company. We expect that reduce fault and save cost by this process. Consequently, we will prevent power losing and black out due to line faults by expulsion of inferiority equipment and prevent heating and line fault. This is possible using Alarming and Auto Locking Wire Compressor that is improve on this study.

• 한국의류학회지
• /
• 제40권3호
• /
• pp.427-436
• /
• 2016

Protective clothing developed for rose flower farmers has been evaluated to improve the working conditions. The requirements of rose farmers were first identified to design protective clothing for farmers working with thorny plants. A fit test was conducted to assess the thermal comfort and protective function against thorn pricking to compare and evaluate the usability of developed experimental clothing with existing working clothes. Based on the survey results of rose farmers' requirements, protective clothing was designed in the form of an apron (which was the most preferred after gloves) with a pattern designed for the production of experimental clothing. For the developed protective clothing, the strap and buckle closure method was selected to open the back of the body as much as possible; in addition, sleeves were made in the attachable form of a half-sleeve to protect the arms from the thorns. The fit test of the developed protective clothing and existing working clothes revealed the temperature and humidity inside the developed protective clothing to be significantly different in the back compared to existing work clothes. In addition to thermal sensations, the subjective humidity sensations were statistically significant different in the developed protective clothing compared to existing work clothes. The subjective protective function for thorn pricking was also found to be satisfactory.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2009년도 제40회 하계학술대회
• /
• pp.1493_1494
• /
• 2009

초고압 전력 케이블용 도체 접속을 위한 접속방법으로 압축형(compressing type), 용접형(welding type), 압축-용접형(CW type; compressing-welding type)의 슬리브는 물론 동과 알루미늄의 이종(nonidentical materials) 접속을 위한 슬리브를 개발 하였으며, 전기적, 기계적으로 검증된 제품 개발을 위하여, 슬리브의 구조 변경과 접속 방법의 차이뿐 아니라 접속 전후의 응력 평가를 위해 슬리브 시편의 인장시험(tensile strength) 결과에 따른 슬리브 제작 및 시험을 진행하였다. 신뢰성 있는 제품 개발과 데이터를 얻기 위하여 초고압용 지중 고압 케이블을 시험 시료로 적용하여 시험 선로(test loop)를 구성하였으며, 이를 통하여 구조와 재질에 따른 접속 방법, 이상 온도 상승 또는 국부적인 고온 부위 발생 여부 등의 전기 시험 및 열싸이클 전압 시험(heating cycle voltage test) 조건을 설정하여 시험 전후의 열신축 등 전기적, 기계적 특성을 평가하였다. 접속 슬리브의 구조 및 재질에 따른 위치별 발열 양상을 체크하였으며, X-ray 장비를 이용하여 슬리브 내부의 압축 및 충진 정도를 점검함으로써 기존 접속 슬리브 보완은 물론 개발된 접속 슬리브의 설계 기준 및 안전율을 설정 할 수 있었다.

• 한국생활과학회지
• /
• 제12권2호
• /
• pp.253-263
• /
• 2003

The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.

• 대한기계학회논문집A
• /
• 제37권2호
• /
• pp.241-248
• /
• 2013

본 논문에서는 상용 회전체 동역학 해석 툴을 이용하여 경사 운전조건을 고려한 대용량 추진 전동기용 베어링 개발에 상사적 설계 방법과 실험적 방법을 적용하였다. 개발된 베어링은 전기적으로 절연이 되어있으며 각 연결부는 2~4mm 의 에폭시 절연판을 연결하여 낮은 열전도 특성을 가지도록 하였다. 본 연구에서는 기존의 저속운전에서 야기되는 베어링 손상 문제를 해결하기 위해 원활한 유막이 생성될 수 있도록 고안한 정압 윤활장치를 적용하여 우수한 윤활특성을 확보하였다. 또한 대형 중량물에 대한 유지보수를 고려하여 반분할 방식의 조립구조를 적용하였다. 본 논문은 고부하, 저속 운전의 추진 전동기 분야에 사용되는 미끄럼 베어링의 주요 핵심설계요소를 언급하였다. 게다가, 시험벤치상에서 다양한 경사조건을 통해 실링부의 오일누유 현상을 확인하였다.