• Journal of the Korean Society for Precision Engineering
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• v.6 no.4
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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.

• Korean journal of food and cookery science
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• v.3 no.1
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• pp.64-70
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• 1987

The effects of salting on the compositional and textural changes of Korean cabbage were studied. The optimum brining conditions were established ana the dietary fiber composition, mineral contents and moisture content of raw and salted Korean cabbage were determined. The cutting test of cabbage was made by Rheometer and the brittleness and chewiness were evaluated organoleptically. The optimum condition for brining was at 20% NaCl concentration for 6 hours. In the compositional changes of Korean cabbage by salting at 20% NaCl solution for one month, the content of hot water soluble pectin (HW-P) increased from 43.6% to 55.9% and that of hexametaphosphate soluble pectin (HM-P) decreased from 35.9% to 29.5%. The contents of cellulose and hemicellulose increased, but that of lignin decreased slightly by salting, showing no significant differences in raw and salted cabbage. The content of Na increased significantly and those of Ca, Mg and K decreased by salting. And also moisture content decreased from 91% to 79%. In the textural changes of Korean cabbage by salting, the maximum cutting force and cutting work increased five times and two and half times respectively. And organoleptic test did show significant increase in chewiness and decrease in brittleness. The maximum cutting force by Rheometer was well correlated with the sensory parameters. The results taken together showed that the changes in textural properties during salting are relevant to the changes in pectic substances, moisture content and mineral contents, but relatively irrelevant to the changes in cellulose, hemi-cellulose ana lignin. And it is considered that the maximum cutting force by cutting test is good means for the expression of texture of Korean cabbage.

• Journal of Biosystems Engineering
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• v.36 no.4
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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.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.1
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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.

• Korean Journal of Applied Biomechanics
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• v.25 no.3
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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.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.1
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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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• 2001.10a
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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 ...

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.424-429
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• 1996

In an attempt to evaluate the effect of six starch sources-potato starch acetate, corn starch acetate, waxy corn starch, corn starch, potato starch, and wheat starch on properties of frozen noodle, amylograph characteristics of starch-wheat flour composites, cooking quality, maximum cutting force and sensory properties of cooked frozen noodles were examined. Compared with 100% wheat flour as control, potato starch acetate and potato starch-wheat flour composites had slightly lower initial pasting temperature and wheat flour composites with acetylated starches, waxy corn starch and potato starch had slightly higher maximum peak viscosity. At cooking quality examination of noodles made from wheat flour-starch composites, volume and weight of cooked noodles were increased and cook loss was decreased with the addition of acetylated starches and waxy corn starch. Maximum cutting forces of cooked frozen noodles containing more than 15% of potato starch acetate and only 15% of corn starch acetate were higher than that of control. Other starches except potato starch improved sensory properties of cooked frozen noodles and the greatest positive effect was acetated potato starch.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.8
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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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• v.28 no.4
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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.