• 한국기계연구소 소보
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• 통권15호
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• pp.91-103
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• 1985

In this paper, temperature distribution and thermal stress are investigated considering engine peak pressure and the time average temperature distribution in the piston under running conditions for the diesel engine. The induced stress are calculated by the Finite Element Method(FEM). The results obtained are summerized as follows. 1) The results calculated by the FEM present good agreement with other numerical solution in literature. 2) It is confirmed that maximum compressive stress are induced in the part of outside wall between the piston crown and the pin bush. 3) In the axial direction, the hoop stresses are changed its sigh at the portion of crown near the inner wall side 4)Large gradient of temperature is shown in the piston crown near the side wall in the axial direction, in the part between the piton crown and the pin bush in radical direction 5)in case of stress distribution of piston wall surface in the axial direction, the hoop stress is a little greater than axial stress, and the latter is greater than the radial stress

• 대한치과의사협회지
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• 제11권11호
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• pp.745-748
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• 1973

The author has studied the effects of pain control by using the Anode-S-3 electro anesthesia in cavity preparations. The electric current value had used 4~10㎂. The results were as follows. 1) The 86 tests in cases of 110 tests as much as 78% of it have showed pain control effects and the 24 of tests as much as 22% had no effects in general. 2) The cases of perfect pain control was only made to 42 tests in cases of 110 tests as much as 38% of it. 3) The pain control with a little inordinary feeilng was 33 tests in 110 of it as much as 30% 4) The slight pain were recorded 22 cases as much as 21% of the tests. 5) The severe pain were recorded 12 cases as much as 11% of the tests. 6) Meanwhlie, the case of increasing pains by using electro-anesthesia was not recorded at all.

• 콘크리트학회지
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• 제6권3호
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• pp.142-151
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• 1994

프리캐스트 콘크리트 대형판 구조물에 있어서 접합부의 강성은 일반적으로 일체식 철근 콘클리트 벽식구조물에 비하여 떨어지는 것으로 알려져있으나 이들 강성에 대한 정량적인 값에 대한 정보가 매우 부족한 실정이다. 이 논문은 몇가지 실험으로부터 도출된 해석적 결과에 근거하여 특히 수평접합부의 압축강도에 관한 정량적 정보를 제공하는 것을 목적으로 한다. 또한 접촉문제로부터의 접근에 의해 구해진 수평접합부의 압축강성값이 위에서 얻은 값들과 매우 유사함을 보여주고 있다.

• 한국관개배수논문집
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• 제17권2호
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• pp.49-56
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• 2010

This study was carried out to survey for morphological change of lower tidal flat near Byunsan-Gosapo beach using single-beam echosounder and sound velocity profiler. Since October 2009 in the center of the region, the erosion occurred about 10~50cm, while either side of the study area is little change. Erosion occurred at the beach, each beach area in the southwest area rather than further accumulation occurred sandbank formed. Observed in the study area near the center of the erosion is the result of ongoing changes that were temporarily due to seasonal changes is not clear. However, the northwestward waves were expected to be a major source of erosion. Because of this, continue to observe the terrain and the local ocean circulation studies will be required.

• 한국농공학회지
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• 제38권2호
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• pp.133-144
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• 1996

To get accurate results, the realistic stress-strain relationships of soils are dependent on a number of factors such as soil types, density, stress levels and stress path. Such attempts are continuously being made by the developement of analytical models for soils incorporating all such factors. Isotropic compression-expansion test and a series of drained conventional triaxial tests with several stress path for Baekma river sand were performed to investigate parameters characteristics of Lade's single work hardening model dependant on the stress path. Using the computer program based on the regression analysis, the values of parameters for the model were determined. In conclusion, the parameters of Lade's model are little influenced by the stress paths. Though yield criterion parameters ( h, ${\alpha}$a) are much influenced by stress level and stress path, the parameters don't have influence on stress-strain behavior.

• 대한치과의사협회지
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• 제53권6호
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• pp.411-417
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• 2015

In an edentulous situation, the oral rehabilitation with complete denture is substantially different from treatment of natural teeth. The artificial teeth arrangement and occlusion are important factor for the stability of the denture. Bilateral balanced occlusion is that stability of the denture is attained when bilateral contacts exist throughout all excursion and static states of the denture during function and, artificial teeth are arrangement in neutral zone where the forces between the tongue and cheeks or lips are equal. This is how dentist make a favorable prognosis. Therefore, dentists are have to be a little more involved in the selection and arrangement of artificial teeth.

• 대한치과의사협회지
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• 제55권1호
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• pp.82-89
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• 2017

Proponents of bilaterally balanced occlusion believe that this occlusal concept is important for denture retention and stability. However, the critical appraisal of the literature reveals no scientific evidence to support the bilaterally balanced occlusion as the ideal occlusal concept for conventional complete dentures. Current evidence suggests that the occlusal concept has little influence on clinical outcomes or patient satisfaction. Additional randomized controlled clinical trials should be developed taking into account the influence of mucosal resiliency, alveolar ridge anatomy, and parafunctional activities on occlusal concept choice. In this paper, various types of complete denture occlusion (bilaterally balanced occlusion, lingualized occlusion, canine-guided occlusion) will be reviewed and compared.

• 한국농공학회지
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• 제30권4호
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• pp.117-126
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• 1988

This paper attempts to characterize general tendency in water level fluctuations at paddy fields, that may be important to efficient irrigation water uses Banweol district was chosen to be the study area, and water levels among irrigation practice parameters were measured daily throughout the irrigation periods of 1985-1986. Time series analyses showed that water levels at fields have strong serial correlationships. A rather long term periodicity was also observed from spectral analyses. Correlationships between water levels at adjacent fields ranged 0.4-0.9, indicating wide variations in irrigation practices. The water levels showed little correlationships with meteorological factors like evapotranspiration, nor with irrigation practices like water supply rates. Standard errors of the average water levels were computed for different number of field plots within a block. The results indicated that low level areal coverage of gauging plots may be applied for field monitoring of daily water level fluctuations.

• 한국농공학회지
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• 제41권1호
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• pp.79-85
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• 1999

Use of soils with crushed expanded polystyrene(EPS) satisfied both recycling of industrial waste and development of new light-weight fill materials. Objectives of the study were to make the mixed the mixed soils with the crushed EPS and to suggest the most rational mixing ration as a fill material. A series of laboratory tests was performed to investigate the relationship between miximum dry density and optimum moisture contenr and to find the variation of CBR for mixtures with 3 soils and 2 sizes of the crushed EPS. Results of the test showed that the sizes fo the curshed EPS had a little effect on the properties of mixed soils. But gradatiion of soils and mixing ration with the crushed EPS were important factors to characterize compaction properties of the mixed soils.

• 대한설비공학회지:설비저널
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• 제16권1호
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• pp.63-73
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• 1987

This research, through the analysis of existing programs, presents a simplified logical program which can show the thermal performance of a system, based only on hourly weather data and the system design data. This program is applicable for analyzing a system of direct heating or recirculation heating which may enhance the performance of an existing solar house. Using these system in the existing systems a little raise in performance. The model analysis of a $100\;m^2$ solar house in the seoul region shows that the following figures are the most efficient and suitable; 1. Installation an81e of collector: $45^{\circ}$ 2. Collector size: $34.56\;m^2$ 3. Capacity of main storage tank: $25\;m^3$