The purpose of this study was to investigate the effectiveness of mental practice in increasing accuracy of performance during motor task. Forty healthy students aged 17 years were randomly assigned to two groups. The experimental group(n=20) performed mental practice; the control group(n=20) performed nothing. The task was dotting. No significant change was seen between pre and post test subtest results following mental practice sessions(p>0.05). The experimental group's accuracy improved a little but this was not valuable statistically(p>0.05). We could not prove that mental practice was effective in increasing accuracy of motor task performance.

In general, research in isokinetic exercise has focussed on studies of peak torque. However, peak torque is not always sufficient to assess the real amount of motion or to determine endurance. In this study, the subjects were 54 healthy students who performed continuous maximal isokinetic knee flexion and extension until their total work per time reached 50% of their maximal total work. Isokinetic curves were then plotted. Total work sums, exercise durations in seconds, and the numbers of repetitions were compared with reference to subject gender, angular velocity and muscle group. The relationship between total work sum, duration and number of repetition and thigh circumference plus leg length was computed. In addition, the characteristics of total work per second and total work per time were calculated. Results showed the total work sums differed greatly from muscle group to muscle group and with different angular velocities. The duration in seconds and the numbers of repetition differed only at higher angular velocity. Males achieved higher levels in every category except for some duration in seconds and some numbers of repetitions. Thigh circumference and leg length were deciding fators in every case, but duration in seconds and number of repetitions were not. These results suggest that measures of endurance should be included along with measures of total work when isokinetic studies are done. Measures of endurance in seconds are more accurate when isokinetic exercise is performed at lower angular velocities and numbers of repetitions at higher angular velocities.

In order to determine the optimum condition and timing for in vitro maturation of oocytes to metaphase of meiosis II (M II), the immatured follicular oocytes were recovered by puncturing the large(1.0~1.5 mm in diameter) and small(<1.0 mm in diameter) follicles in the ovaries of rabbits treated intramuscularly with a single dose of 100 TU PMSG 68 hours previously. The follicular oocytes were classified into three grades by the attachment of cumulus cells. The Grade I and II follicular oocytes from large follicles were cultured in BO-DM medium with 10% FCS, 35 g /nl of FSH, 10 g /ml of LH and 1 g /ml of estradiol-17 at 39t in a 5% incubator for 11 to 23 hours. In 3 hours interval during the culture period, the oocytes were harvested and their cumulus cells were removed with hyaluronidase. The denuded oocytes were stained with Hoechst 33342 dye and their meiotic status and extrusion of the first polar body (PB) were examined under a fluorescence microscope. Also the fragmentation of the first PB and the distance between the first PB and nucleus were examined. The results obtained were as follows: 1. The mean recovery rate of follicular oocytes from the large and small follicles was 59. 9 and 31.3%, respectively. The mean number of oocytes recovered per rabbit and the Grade I percentage were 14.6 and 94.4% in large follicles, but 2.1 and 61.1% in small follicles, respectively. All the parameters examined were different significantly (p<0.05) between both the folliclular size. 2. Most of the follicular oocytes(86.8%) were matured in vitro to M II phase in 14 hours in Grade I oocytes, but the significantly(p<0.05) less oocytes(45.5%) were matured in Grade II oocytes. 3. The first PB was extruded in most of the oocytes(94.7%) in 14 hours of culture with the fragmentation rate of 29.6%, but the fragmentation rate of the first PB increased significantly (p<0.05) as the culture period for maturation was longer to 20 hours(63.5%). 4. The distance between the first PB and nucleus was increased linearly (p<0.05) as the maturation time passed from 14(7.1rn) to 23 hours(58.4m). 5. From the above results it was concluded that the optimum time for in vitro maturation culture might be 14 hours in the follicular oocytes from rabbit primed with PMSG for 68 hours, expecially when these follicular oocytes were used for recipient cytoplasms in embryo cloning.

수산화물법에 의해 제작된 α-stannic acid의 열분해 거동과 SnO2분말의 성질에 미치는 잔류염소이온의 영향을 관찰하였다. SnCl4와 NH4OH 수용액을 중화시켜 α-stannic acid침전물을 제작하고 NH4NO3수용액으로 세척하였다. 분말내의 잔류 염소이온의 양을 주절하기 위하여 세척정도를 3단계로 조정하였다. 세척후 100˚C에서 건조하고, 500˚C ~ 1100˚C에서 하소함으로써 SnO2분말을 제조하였다. α-stannic acid의열분해 거동ㅇ르 DT-TGA 와 FTIR을 통하여 관찰하고, SnO2분말의 조성과 입자크기 및 비표면적을 각각 AES, TEM 및 BET을 통하여 측정하였다. 잔류 염소이온 양이 감소되면, 저온 하소시 일차입자의 상대적 크기가 커지는 반면 고온하소시에는 상대적으로 감소되었ㄷ. 잔류 염소이온의 일부는 α-stannic acid내의 격자산소 자리에 위치함으로써, 저온가열시 결정수탈리와 결정화를 지연시키고 또한 고온가열시에는 이의 증발에 의해 산소공공이 생성되어 소결을 촉진시킨다고 제의하였다.

This study was designed to develop an objective method of strength measurement of muscles controlling the wrist joint in normal subjects. Forty subjects (20 male, 20 female) with a mean age of 22 years, were tested isokinetically at and . Results were as follows, 1) Peak torque for wrist flexors, extensors were significantly different for both speeds, but wrist ulnar deviator, radial deviator peak torques were not, 2) Mean values for all muscle groups controlling the wrist were not significantly different for both speeds in the female group, 3) All mean values at both and were significantly different between males and females, 4) Means and standard deviations of wrist joint angle of movement at peak torque were determined.

The purpose of this study was to establish a baseline in order that individuals may exercise safely. Sixty healthy students who were divided into two groups participated in the experiment. One group exercised both arms and legs at 60 rpm and the other at 90 rpm. There was a significant difference between arm and leg exercise in diastolic blood pressure (DBP) and time to target heart rate (tTHR). DBP decreased more in the upper (U//E) than the lower extremity (L/E), but tTHR increased more in the L/E than the U/E (p < 0.05). Systolic blood pressure (SBP) was similar for both arm and leg exercise (p > 0.05). There was also no significant difference between 60 rpm and 90 rpm in SBP, DBP or tTHR in either arm or leg exercise (p > 0.05). In conclusion, the slope of the linear increase in heart rate was steeper for U/E than L/E work. Therefore L/E exercise is safer than U/E exercise.

도로 안전 구조물을 썰계하고 동적 퍼포먼스톨 측정하기 위하여 시행되는 충돌시험시 충돌차량의 운동량， 륙히 각가속도를 Euler 방정식의 수치적분을 통하여 구하는 기법을 셜명하였다. 수치척으로 가장 안정적인 9-array 시스댐안에 내재된 여러 형태의 7, 8-array 서브시스댐들의 시스댐 미분 방정식 빛 이들 방정식의 수치 적분시 안정성올 실험데이터를 이용하여 파악하였다. 기본척인 9-array 안에 있는 6개의 8-array 시스댐들은 모두 수치적으로 안정성올 보였고 12개의 7-array 시 스댐들중 6개는 안정성올 보이고 6개는 불안정하였다. 안정성올 보이는 내재된 서브시스댐을 활용하면 기본 9-array 시스댐을 구성하는 센서의 일부 고장시 효과적으로 각가속도를 측정 할 수 있는 fail-safe 시 스댐을 구 성할수있디.

액상요구르트의 제조시에 분유에 의한 산생성불량의 원인을 규명하고 이의 개선방법을 검토하였다. TCA-soluble peptides이 함량이 낮은 탈지분유는 모두 요구르트 제조시에 산생성이 불량하였고, TCA-soluble peptides의 함량이 높은 탈지분유는 모두 산생성이 양호하였다. TCA-soluble peptides의 함량이 낮은 불량탈지분유에 Na-caseinate의 trypsin 분해물 첨가는젖산균의 산생성을 촉진시켰다. 그러나 Na-caseinate의 papain 분해물 첨가는 촉진효과를 나타내지 못했고, 세균성 중성 protease 분해물의 첨가는 억제 효과를 나타내었다. Na-caseinate의 trypsin 분해물 첨가는 탈지분유의 TCA-soluble peptides 함량이 낮고 starter 젖산균의 단백질 분해능력이 약할 경우에 젖산균의 증식 촉진효과와 산생성 촉진효과가 크게 나타났다. TCA-soluble peptides의 함량이 부족한 탈지분유에 Na-caseinate 미분해물을 첨가하여 발효시킨 액상요구르트는 유단백질의 침전이 발생하였으나, Na-caseinate의 trypsin 분해물을 첨가하여 제조한 것은 정상적인 탈지분유에서와 같이 단백질의 침전이 발생하지 않았다.

In the general process of design for aerobic digestion, the design for field plant of which inflow pattern is continuous inflow is performed using the results from lab scale batch reactor. However, the recent researchers reported that the general designs were performed as over-estimated, Therefore, in this study, laboratory batch experiments were carried out at $20^{\circ}C$ and pH 7.5 on the aerobic digestion of waste activated sludge at different solid levels. This treatise could consider the negligence about effective digestion periods the usage of VSS as solid concentration, and the effect of initial solid concentration of solid degration rate coefficient($k_d$) as reasons of the overestimated design, and showed the scheme of how to design for aerobic digestion from batch experiment.

This study was conducted to present a method that determine the optimum conditions for the preparation of chinese whole cabbage kimchi. After Sensory and chemical characteristics of kimchi with various salt concentration in brine, brining time and storage period at equal saltiness were measured, the optimum conditions for the preparation of chinese whole cabbage kimchi were determined with the use of the response surface methodology. The results are summarized as follows; 1. The more salt concentration in brine, the longer brining time and storage period, resulted in the lower pH and the higher titratable acidity of kimchis. As the salt concentration in brine and brining time increased, kimchi reaches at optimum titratable acidity of it within a shorter time. 2. As the salt concentration in brine and brining time increased, content of succinic acid decreased but that of lactic, acetic, and propionic acid increased. Amount of citric, malic and succinic acid decreased but that of lactic, acetic acid increased, with storage day. 3. Sensory data showed that firmness and green cabbage flavor of kimchi decreased while toughness, carbonic mouthfeel, sourness and staled flavor increased with increased salt concentration in brine, brining time and storage day. As the storage period increased, crispness of kimchi decreased. 4. The optimum conditions for the preparation of chinese whole cabbage kimchi were as follows: Optimum salt concentration in brine, brining time, and storage period were 19.5%, 3 hours and 45 minutes, and 12 hours.