• 한국운동역학회지
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• 제17권4호
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• pp.17-25
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• 2007

The purpose of the study is to give basic data for the improvement of the skill and to show an exemplary position for squash club members or trainers thru a comparative analysis on the kinematics and kinetics variables on the forehand drive motion in playing squash. The objects of the research are divided into two sections, skilled group(n=8) and unskilled group(n=8). The skilled group is composed of professional players currently working and unskilled group is career of six month, both of lives in B city. In this research, to gather the data 3D motion analysis and test result analysis using force platform was used. The variables are duration, position, segment velocity, segment acceleration and etc. in using force platform. The results are as follows: 1. The duration per phase of the skilled is 0.18sec P1(DS) while that of unskilled is 0.32sec. in P2(FT), the duration of the skilled is 0.29sec, that of unskilled is 0.34sec. Average of the duration of the skilled is 0.48sec, while the unskilled, 0.66sec. 2. Regarding positional movements per event, the unskilled has a relatively higher position in center of gravity, shoulder joint, elbow joint compared with that of the skilled. Generally speaking, positions of the unskilled is higher than the skilled. 3. In segment velocity per event, R-shank, R-upper arm, R-forearm and racket. The skilled is faster than the unskilled. we found a big dig difference in shank. 4. In acceleration per event, there was a big difference in upper-arm and fore-arm of the impact. 5. The skilled group on the force platform shows relatively stable and regular changes while the unskilled shows unstable from the touch down to initial 20% the force value of central support period after the impact moment decreases rapidly and the center of gravity is not moved well. 6. The maximum force value of the skilled is 1019.7N. it is found 19.86% of the total duration. That of the unskilled is 639.2N, it is found 20.67% of total duration.

• 한국식품과학회지
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• 제48권6호
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• pp.565-568
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• 2016

고온에서 가열 살균한 쇠고기의 복합인산염 전처리 유무에 따른 조직 경화 개선 효과를 고기 보수력 증가 측면에서 고찰한 결과 고기 중량 대비 0.35% (w/w) 복합인산염을 갈비살 및 우둔살에 각각 1시간 혼합, 방치한 후 $100^{\circ}C$에서 5-40분간 가열시 무처리구 대비 보수력의 간접 지표인 중량 기반 수율이 5-10% 내외 향상되는 것으로 나타났다. $115^{\circ}C$에서 30분간 가열 살균한 쇠고기에 대한 0.35% (w/w) 복합인산염 1시간 염지 및 $100^{\circ}C$, 2분 조건의 블렌칭 공정 조합 전처리 효과를 무처리구와 비교한 결과 텍스처 개선 효과가 유의차(p<0.05) 있게 나타났다. 전처리 우둔살 및 갈비살의 기계적 질김 강도가 각각 1.3, $1.4kg_f$로서 무처리구의 2.0, $1.8kg_f$에 비해 36, 19% 텍스처 질김 정도가 개선되었다. 전처리 후 가열 살균한 쇠고기에 대한 저장시 질긴 텍스처 변화를 $10^{\circ}C$, 30일 보관 후 기계적 질김 강도 비교를 통해 고찰한 결과 갈비살 및 사태살에서 무처리구 $1.7kg_f$에 비해 $1.1kg_f$의 값을 보여 평균 35% 내외의 질긴 텍스처 개선 효과가 유의차 있게 나타났다(p<0.05).

• 한국식품과학회지
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• 제5권3호
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• pp.174-177
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• 1973

한우(韓牛)의 사태근육(筋肉)에 단백질분해효소(蛋白質分解酵素)를 첨가(添加)해서 total tryptophan 과 free tryptophan을 spectrophotometric method로 분석(分析)한 결과(結果)는 다음과 같다. 1. 단백질분해효소(蛋白質分解酵素)를 0.01%, 0.05%, 0.1%로 첨가(添加)함에 따라 total tryptophan 과 free tryptophan은 계속 증가(增加)하였다. 2. Total tryptophan은 단백질분해효소(蛋白質分解酵素)를 육중량(肉重量)의 0.05% 첨가시(添加時) 그 증가율(增加率)이 가장 높았다. 3. 단백질분해효소(蛋白質分解酵素) 첨가(添加)에 따른 free tryptophan의 함량변화(含量變化)는 그다지 심하지 않았다.

• 한국가금학회지
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• 제50권2호
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• pp.91-99
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• 2023

본 연구는 생산 능력이 우수한 삼계용 토종닭을 개발하기 위한 것으로 국내 고유 토종닭 종자들 간 교잡으로 생산한 6개 조합의 재래토종닭(KNC-SCYC, SCYD, SDYC, SDYD, SYYC, SYYD)과 상업용 토종실용닭인 GSP-한협 토종닭의 생산 능력을 백세미와 비교 분석하였다. 생산 능력의 검정은 품종별 각 100여수씩 총 756수를 대상으로 발생 후부터 7주령까지 생존율, 체중, 정강이 길이, 사료 섭취량, 사료요구율 및 도체율을 조사하였다. 분석 결과, 발생 후부터 7주령까지 전체 시험구의 평균 생존율은 거의 100%로서 품종 간 차이는 없었다. 체중은 모든 주령에서 품종 간에 유의한 차이를 보이며(P<0.01), 5주령 체중에서 백세미는 863.8±76.9 g, GSP-한협 토종닭은 804.7±72.5 g, 재래토종닭 조합구들의 평균 체중은 543.0±61.8 g이었다. 삼계 출하체중인 850 g 도달일령은 백세미는 34.5일, GSP-한협 토종닭은 37.5일, 재래토종닭 조합들은 45.8-48.8일로 추정되었다. 850 g 생체중 기준 도체율은 재래토종닭은 63.3%, 백세미는 60.4%, GSP-한협 토종닭은 56.1%로 분석되었다. 체중 850 g을 기준으로 품종 간 정강이 길이를 비교하였을 때 재래토종닭 KNC-SYYD구는 7.6 cm, 백세미는 7.8 cm, GSP-한협 토종닭은 8.0 cm로 측정되었다. 체중 850 g 도달일 동안 품종 간의 사료요구율을 비교하였을 때 백세미는1.81, GSP-한협 토종닭은 2.17, 재래토종닭 KNC-SCYC구는 2.27으로 나타났다. 이상의 결과를 종합할 때 토종닭의 산육 능력 및 사료 이용성은 백세미에 미치지 못하나 토종닭은 도체율이 양호하고 백세미보다 짧은 정강이 길이 때문에 삼계탕 원료육으로의 활용 가치가 높다고 판단된다. 토종닭 중 GSP-한협 토종닭과 재래토종닭 KNC-SYYD 조합 등은 상대적으로 산육능력, 정강이 길이 및 도체 성적이 우수함으로 백세미를 대체할 수 있는 토종 삼계 후보로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권3호
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• pp.426-433
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• 2008

Heat stress is major welfare problem in the poultry industry. Huge economic losses occur every year because of mortality and decreased production due to high environmental temperatures. This experiment was conducted to determine the effects of level of inclusion of ascorbic acid supplementation to the diet on performance, carcass composition and bone characteristics of male turkeys during high summer temperature. A total of 120 day-old turkey chicks were wing banded at hatch and randomly distributed into 3 treatment groups. Three diets were formulated to provide a similar nutrient profile with the exception of using three graded levels of ascorbic acid, namely 0, 150 and 300 mg/kg of the diet. The experimental diets were used from 0 to 18 weeks of age. Body weights, feed intake and feed conversion ratio, slaughter weight, carcass yield, portions, composition and thigh and breast pigmentation of the turkeys were not affected by ascorbic acid (p>0.05). Also, shank and tibia bone characteristics were not affected by ascorbic acid (p>0.05).

• 대한기계학회논문집
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• 제18권8호
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• pp.1952-1966
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• 1994

The body segment parameters of twelve young male Korean were measured to compare with the results of foreign cadaver studies. A human body was assumed to have fourteen body segments. The mass of each segment was measured with a water immersion test and the mass center of a segment was determined on the balance platform by changing postures. In the case of Korean, because of the difference in body proportion, the mass center of whole-body is located further from the distal end of head(Korean : 44.9% vs. Caucasian : 41.2%), and the mass center of each segment also located in different proportional locations. The existing regression equations, which can estimate segment mass based upon the anthropometric dimensions, estimates segment mass (the mass of shank) for Korean with 13% error. Therefore, it is not recommended to estimate the mass, and the moment of inertia of body segment of Korean based on the existing equations. However, the density information of body constituents was similar enough to apply it to Korean density. It was validated by the comparison between the results of the direct immersion method and 3-dimensional volume reconstruction of segment form the cross sectional images of CT-scan. The average body density measured form twelve subjects was $1.035{\;}kg/m^3$ and showed deceasing trendency.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1993년도 Proceedings of International Conference for Agricultural Machinery and Process Engineering
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• pp.1043-1052
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• 1993

Field experiments were conducted to determine the optimum combination of performance parameters of a single-shank, tractor-mounted oscillating subsoiler. Tests were conducted at frequencies of oscillation of 3.7 , 5.67, 7.58, 9.48 and 11.456Hz ; amplitudes of 18, 21, 23.5, 34 and 36.5 mm ; and forward speeds of 1.84, 2.19 and 3.42 kmph at moisture content close to the plastic limit of the soil. It was observed that there was a reduction in average draft but an a increase in average total power requirement for oscillating than non-oscillating subsoiling. The draft and power ratios were significantly affected by the forward speed, frequency and amplitude. Their combined interaction expressed in terms of the velocity ratio parameter( the ratio of peak tool velocity and forward speed) however has the strongest influence. At the same velocity ratio, the draft reduction and power increase were less at higher amplitude of oscillation . As the oscillating frequency is increased toward the soil resonance the draft requirement becomes less. For the field conditions tested. the optimum operation was obtained at an amplitude of 36.5mm, frequency of 9.48Hz and speed of 2.19 kmph with a draft ratio of 0.33 and a power ratio of only 1.24.

• 한국해양공학회지
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• 제7권2호
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• pp.121-130
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• 1993

A study off riction welding of high speed steel(SKH 51) bar for blade side to carbon steel(STC 3)bar for shank side was carried out experimentally through tensile test, hardness test, microstructure, and acoustic emission (AE) test. So, this paper deals with optimizing the welding conditions and the real-time quality (strength) evaluation of friction weleded joints by acoustic emission technique. The results obtained are summarized as follows: (1) For friction welded joints of SKH 51to STC 3 steel bars, the total upset (U) increases linearly with an increase of heating time (t sub(1)). (2) The determined optimum welding conditions are heating time (t sub(1)) 7-9 sec, upsetting time (t sub(2)) 5 sec, heating pressure(P sub(1)) 12 kg sub(f)mm supper(2), upsetting pressure (P sub(2)) 15 kg sub(f) mm supper(2) and rotating speed (n) 2, 000 rpm, resulting in a computed relationship between the tensile strength of the joint .sigma. (kg sub(f) mm supper(2)) and the heating time t sub(1) (sec) as the following. sigma.=2.39t sub(1)

• 한국정밀공학회지
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• 제10권1호
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• pp.34-41
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• 1993

SUS304 is wellknown as difficult-to-machine materials. It is easy to appear workhardened, and workhardening is one of the causes of groove wear on the tool. In this paper, the author would like to compare the width of flank wear with that of groove wear, and to find whether the groove wear can be used as a criterion of a tool life. The design of the twelve tests provides three levels for each variable (speed: 200m/min, 118m/min, 70m/min; feed: 0.3mm/rev, 0.17mm/rev, 0.1mm/rev; depth of cut: 0.4mm, 0.28mm, 0.2mm). The study of tool-life testing by statistical technique follows usual most scientific sequence. So the tool-life predicting equation is calculated by the method of least squares. The overall adequacy of the model can be verified by the analysis of variance. The results obtained are as follows : 1) When SUS304 is cut in 200(m/min), the width of flank wear is much larger than that of groove wear. 2) In cutting speed 118m/min, flank wear is a little larger than groove wear and in the cutting speed 70m/min, the latter is a little larger so that it is reasonable to determine the tool life according the crierion by groove wear in the low cutting speed (less than 70m/min). 3) Owing to the burr the depth of engagement along the cutting edge is extended toward the shank.

• 한국군사과학기술학회지
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• 제14권3호
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• pp.414-422
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• 2011

In this paper, we analyze the standards of the bolts for maintaining the products. The maintainer don't know the detail information of bolts by seeing the shape of bolts when they repair the products. So they waste much time and cost. To solve the these problem, we propose the new systematical discrimination of bolts. To propose the discrimination code, we divide the shapes of the bolts into four classes(head, internal drive, shank and end). User can fine preferentially similar standards by just the shapes of bolts under the this discrimination code. And, User can find the standards of bolts that they want by using the additional information such as measurements. We will reduce the cost and time for the maintaining the products by using the proposed discrimination code.