• 한국정밀공학회지
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• 제6권4호
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• pp.94-102
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• 1989

The effect of plastic strain on the surface integrity of mild steel (SS 41) was studied. This paper shows that the recrystallization technique is adequate to evaluate the plastic strain in a machined surface experimentally. The relations between the plastic strain and the machining conditions are quantitatively evaluated by using the recrystallization technique. The obtained results are summarized as follows. 1. The surface integrity of steel is considerably influenced by the amount of surface region deformation produced by changes in cutting conditions. 2. The plastic strain in machined surface produced by changes of the cutting conditions is evaluated by the recyrstallization technique. 3. The plastic strain increases with the increase of depth of cut and the decrease of rake angle. 4. When the cutting force is high and the rake angle is small, the value of maximum true strain reaches to high. 5. The maximum true strain is related to the cutting energy, and the values increase with the increase of the unit shear and total engergy in constant depth with the increase of the energy values.

• 한국식품조리과학회지
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• 제3권1호
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• pp.64-70
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• 1987

배추의 성분조성 및 조직감의 변화에 대한 염장효과에 대하여 연구하였다. 최적 염장조건을 알아보았으며 원료배추 및 염장배추의 dietary fiber 성분조성 무기질 함량 및 수분함량을 측정하였다. 배추의 조직감은 Rheometer에 의한 cutting test에 의하였으며 아삭아삭한 성질 및 씹힘성은 관능검사에 의해 평가되었다. 배추절임을 위한 최적조건은 절임농도가 20%, 절임시간은 6시간이었다. 배추를 20% NaCl용액에서 한달간 염장에 의한 성분변화에 있어서 HW-P는 43.6%에서 59.5%로 증가하였으며 HM-P는 35.9%에서 29.5%로 감소하였다(P<0.05). 그러나 전체 펙틴함량은 거의 변화하지 않았다. 셀룰로오즈, 헤미셀룰로오즈의 함량은 증가하였으나 리그린 함량은 감소하였는데 유의적인 차이는 없었다. Na함량은 현저히 증가하였으나 Ca, Mg, 및 K 함량은 감소하였다. 또한 수분함량은 91%에서 79%로 감소하였다(p<0.05). 배추를 20% NaCl용액에서 한달간 염장에 의한 조직감의 변화에 있어서 최대절단력 및 절단면적은 각각 5배 및 2.5배로 증가하였으며 관능검사 결과 씹힘성은 높아졌으나 아삭아삭한 성질은 낮아졌다(P<0.05). Rheometer에 의한 조직감 parameter와 높은 상관관계를 나타내었다. 이상의 결과로부터 배추를 20% NaCl 용액에서 한달간 염장과정 중 조직감의 변화는 펙틴질 함량, 수분함량 및 무기질 함량의 변화와 관련이 있으나 셀룰로오즈, 헤미셀룰로오즈 및 리그린 함량과는 비교적 관련이 없는 것으로 나타났다. 또한 cutting test에 의한 최대 절단력이 배추의 조직감을 표현하는 좋은 방법이라고 생각되어진다.

• Journal of Biosystems Engineering
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• 제36권4호
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• pp.252-256
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• 2011

Consumption of chicken feet has been increasing recently, thus it was necessary to produce good quality of bone less chicken feet. In the process of bone removal during chicken feet production, feeding, conveying, cutting and bone removing process takes about 90% of overall labor. Therefore, the development of a chicken feet-bone remover was necessary to reduce the cost of labor. There has been few research on the chicken feet bone removers so far in Korea as well as worldwide. So the main objective of this study was to develop a chicken feet-bone remover which is suitable for domestic circumstances. The average length of chicken feet was 113.3 mm with maximum and minimum lengths of 135.8 mm and 92.2 mm, and the average diameter of chicken leg was 12.5 mm, average width of the toe was 56.2 mm and the average weight of chicken feet was 26.4 g with maximum and minimum weight of 39.3 g and 16.9 g, respectively. Also, the average moisture content was 64.7% (w.b). The average cutting force of little toes was 15.6 N for the size ranges of less than 3.5 mm, 22.5 N, 3.5~6.0 mm and 30.3 N for larger than 6.0 mm in diameter, respectively.

• 한국정밀공학회지
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• 제13권1호
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• pp.123-130
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• 1996

The procedure on the design of a new tungsten cabide throw-away cutting tool system for deep grooving or cut-off machining is suggested. For relieving the maximum stress level at the corner radius of the blade holder, the finite element method is used. Also the pulling test device is proposed for measuring the holding force of the insert between the blade holder and the insert considering the materials in contact and configuration parameters of the holder.

• 한국운동역학회지
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• 제25권3호
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• pp.363-370
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• 2015

Objective : The purpose of this study was to give the basic data for the cutting movement with the various angels on the poly urethane. Method : Ten healthy men voluntarily participated in this study. A three-dimensional motion analysis system (VICON) and force plates were used to analyze the movements of the joints for the lower extremities. For the statistical analysis the IBM SPSS 21.0 was used to perform repeated measured ANOVA and post-hoc comparison result was used to perform the Scheffe and the level of significance was set up at ${\alpha}=.05$. Results : There were significant differences for the time required for the increasing angles of the cutting movement(p<.05). In addition, there were significant differences for the maximum dorsiflexion, plantarflexion of ankle joint, maximum flexion of knee joint and hip joint with the increasing the angles of cutting movement(p<.05). Also, there were significant differences for the maximum adduction and abduction angle of the hip joint with the increasing of the angles of cutting movement. There was signigicant difference for the resultant utilized coefficient of friction(RuCOF) for the increasing angles of cutting movement(p<.05). Conclusion : There was a pattern to increase the coefficient friction with the angle of cutting direction. Also, it would be possible to use the poly urethane for the outdoor floor with the results of this study.

• 한국기계가공학회지
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• 제14권1호
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• pp.1-8
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• 2015

Productivity of machining using machine tools is affected by cutting conditions such as cutting speed, feedrate and depth. However, undesirable conditions that lengthen the machining cycle and shorten the tool life occur frequently because determination of cutting condition is known to depend on human experience. This paper presents a method of cycle reduction by removing undesirable conditions. For cycle reduction, maximum cutting load is determined using commercial FEM simulation code. The feedrate in the NC program is altered based on a predetermined cutting load value. To make a decision on the proposed effectiveness, a simulation is performed for the brake hub parts of an automobile. From the evaluation, it was found that the cycle reduction was under 15%.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.47.1-47
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• 2001

The drilling process has a great importance for the production technology due to its widerspread use in the manufacturing industry. In order to enhance a maximum production rate and prevent the drill from the damage, it is important to monitor and control the drilling system. Thrust force and cutting torque are the main output variables in the design of drilling control systems. In this paper, an alternative estimation method of thrust force by using flexible neural networks is proposed. Flexible neural network uses the sigmoid activation function with adjustable parameter in order to enhance the approximation accuracy ...

• 한국식품영양학회지
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• 제9권4호
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• pp.424-429
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• 1996

전분의 첨가가 냉동면의 조직감과 관능적 특성에 미치는 영향을 밝히기 위하여 감자초산변성전분, 옥수수초산변성전분, 찰옥수수전분, 옥수수전분, 감자전분, 밀전분 등 6종의 전분을 함량별로 첨가하여 복합분을 제조하였다. 이들의 아밀로그래프, 제면시의 조리시험, 냉동, 해동후 면의 최대절단강도를 측정하고 관능평가하였다. 감자초산변성전분과 감자전분을 첨가한 복합분의 호화개시온도는 대조구인 소맥분 100%보다 다소 낮아졌다. 최고점수는 초산변성전분류, 찰옥수수, 감자전분을 첨가한 경우 다소 높아졌다. 조리시의 체적과 중량은 다소 증가하고 고형분 용출량은 변성전분과 찰옥수수전분을 참가한 경우 다소 감소하였다. 냉동, 해동 조리 후 면의 최대절단강도는 감자초산변성전분 15%와 20%, 옥수수초산변성전분 15%를 첨가한 경우에 대조구보다 커졌다. 감자전분을 제외한 나머지 5종의 전분을 첨가시에 냉동면의 조직감과 색깔이 다소 향상되는 것으로 나타났다. 그 중에서 감자초산변성전분의 효과가 가장 높았다.

• 한국정밀공학회지
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• 제32권8호
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• pp.693-698
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• 2015

Recently, the quality of products after the corresponding machining processes were scrutinized in the interest of maintaining a high product-quality standard. The structure and stability of machine tools are important for the prediction of product quality. A structural analysis needs to be carried out to achieve the stable design of machine tools before the initial design stage in the manufacturing process of a precision product. In this study, a structural analysis was carried out using a finite element analysis (FEA) simulation to obtain the design stability of the main parts of a grinding machine. The sizes and locations of both the maximum stress and deformation in consideration of the cutting force of the chuck, tail stock, and bearing of the grinding machine were analyzed. Finally the grinding machine was successfully developed.

• Wind and Structures
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• 제28권4호
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• pp.203-213
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• 2019

The topography and geomorphology are complex and changeable in western China, so the railway transition section is common. To investigate the aerodynamic effect of the subgrade-tunnel transition section, including a cutting-tunnel transition section, an embankment-tunnel transition section and two typical scenarios for rail infrastructures, is selected as research objects. In this paper, models of standard cutting, embankment and CRH2 high-speed train with the scale of 1:20 were established in wind tunnel tests. The wind speed profiles above the railway and the aerodynamic forces of the vehicles at different positions along the railway were measured by using Cobra probe and dynamometric balance respectively. The test results show: The influence range of cutting-tunnel transition section is larger than that of the embankment-tunnel transition section, and the maximum impact height exceeds 320mm (corresponding to 6.4m in full scale). The wind speed profile at the railway junction is greatly affected by the tunnel. Under the condition of the double track, the side force coefficient on the leeward side is negative. For embankment-tunnel transition section, the lift force coefficient of the vehicle is positive which is unsafe for operation when the vehicle is at the railway line junction.