• 대한교통학회지
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• 제7권2호
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• pp.89-111
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• 1989

This study concentrates on a basic investigation research related to some of parameters to be used for the analysis of capacity and the level of service for signalized intersections. The parameters to be studied are ideal saturation flow rate, large vehicle's passenger car equivalent(PCE) ane the lane utilization factors of through and left turn vehicles. The field data were collected at six intersections in Seoul using video cameras so as to reflect conditions in urban areas. In this study discharge headway based on a rear bumper of each vehicle was used and all the parameters were estimated using a regression technique. The findings of this research are as follows : 1. The saturation headway and saturation flow rate on a single lane with the lane width of 3.1m are 1.652 seconds and 2,180 pcphgpl. It was found that the frist 5 vehicles in the queue experience some start-up lost time. 2. It was confirmed that the new method adopted for the estimate of large vehicle's PCE gives larger PCE values than those derived from the method commonly used. 3. For the estimate of lane utilization factors of through and left turn vehicles, a relationship was established and the corresponding formulas were developed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.383-385
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• 2007

IEEE 802.15.4 is a standard designed for low rate wireless personal area networks(LR-WPANs). This paper presents the analytical model for to derive the saturation throughput of collision avoidance protocol of IEEE 802.15.4 in ad hoc network. we assume that nodes placed according to a two-dimensional Poisson distribution.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.491-495
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• 2004

The industries use polymer materials for many purposes for they have many merits. The costs of these materials take up too great a proportion of the overall cost of products that use these materials as their major material. It is advantage for polymer industries to reduce these costs. The microcellular foaming process was developed in the early 1980s to solve this problem and proved to be quite successful. Microcellular foaming process uses inert gases such as $CO_2$, $N_2$. As these gases solve into polymer matrices, many properties are changed. The microcellular foaming process makes the glass transition temperature of polymers to low, and diminish the residual stress of polymer matrices. Besides, the microcellular foaming process has several merits, impact strength elevation, thermal insulation, noise insulation, and raw material saving etc. This characteristic of microcellular foaming process has influenced by cell morphology. The cell morphology means cell size and cell density. The cell morphology has influenced by many factors. The examples of factor are pressure drop rate, foaming temperature, foaming time, saturation pressure, saturation time etc. Among their factors, pressure drop rate is the most important factor for cell morphology in microcellular foaming injection molding process. This paper describes about the cell morphology change in accordance with the pressure drop rate of microcellular foaming injection molding process.

• 한국수산과학회지
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• 제15권3호
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• pp.179-184
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• 1982

Lartobacillus bulgricus를 glucose를 제한기질로 하는 합성배지에서 연속배양한 결과를 요약하면 다음과 같다. 1. 본 실험 model은 Monod의 chemostat 이론을 적용시킬 수 있다. 2. 본 실험 model에서의 최대 cell production rate는 $0.178 g/1{\cdot}hr$로서 회석율 $0.414hr^{-1}$ 일 때이다. 3. 연속배양 결과 saturation constant($K_s$)는 7.69g/l, 최대비증식속도$(V_{max})$는 $0.62hr^{-1}$ 이었다. 4. wash out 현상은 $0.51hr^{-1}$에서 일어났으며cell yield coefficient는 0.016g/l 이었다.

• 대한통합의학회지
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• 제11권2호
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• pp.141-147
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• 2023

Purpose : This study aimed to find out the effect of aerobic exercise using Bruce protocol on heart rate, oxygen saturation, and blood pressure after recovery from COVID-19 infection. Methods : In this study, 34 students from D University located in J city were targeted, COVID-19 infected group (17 people) and non-COVID-19 non-infected group (17 people). The Bruce protocol using a treadmill was applied to the aerobic exercise of this study. The Bruce protocol has in the first stage of METs 4 (slope 10 %, speed 2.7 km/h). The second stage was METs 5 (slope 12 %, speed 4 km/h), and the third stage was METs 6 (slope 14 %, speed 5.4 km/h). All measurements were measured 3 times and the average value was used. Results : As a result of this study, as a result of comparing heart rate changes according to aerobic exercise using the Bruce protocol. EG group and the CG group increased significantly according to the progressive exercise load (METs 4~5), and in the third stage of the Bruce protocol between groups, The EG group showed a significantly lower heart rate. As a result of comparing changes in oxygen saturation and blood pressure, there was no significant difference between the EG and C groups according to the gradual exercise load. Conclusion : In conclusion, there was no difference between normal and pressure when MET of moderate intensity exercise (4 to 6) was applied to the effect on heart rate, oxygen saturation, and blood pressure in healthy adults who were fully recovered from COVID-19. Secondary side effects may occur when high intensity exercise with a MET of 6 or higher, so it is strongly recommended that hospitals or specialized institutions measure exercise and physical ability according to individual exercise intensity.

• Korean Journal of Acupuncture
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• 제26권4호
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• pp.23-38
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• 2009

Objectives : The purpose of this study was to identify the effect of the tonification & sedation manipulation for LI4 and KI7 on lacking of sweating in cold environment. Methods: The participants were divided into 3 groups as intact group without acupuncture, acupuncture group inserting and twisting with LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) and acupuncture group inserting and twisting with LI4 sedation and KI7 tonificaton method(LI4-purge KI7-tonify). We obtained baseline data at cold condition with the temperature $14{\pm}1^{\circ}C$. After making the participant staying in cold condition for 10 minute, we measured sweating rate in skin surface, body temperature, oxygen saturation, pulse rate, systolic blood pressure, diastolic blood pressure, deoxy-Hb and oxy-Hb in subcutaneous. Results : After acupuncture in cold environment, the sweating rate in skin surface significantly decreased in KI7-purge LI4-tonify group comparing the intact groups. The body temperature significantly increased in LI4-tonify KI7-purge and LI4-purge KI7-tonify groups comparing the intact group. The oxygen saturation significantly increased in LI4-tonify KI7-purge group comparing the intact group. Conclusions : These findings indicated that LI4 tonificaton and KI7 sedation method(LI4-tonify KI7-purge) could be effective for production of sweating in cold condition.

• 대한물리의학회지
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• 제17권4호
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• pp.37-43
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• 2022

PURPOSE: To find out how wearing a mask due to COVID-19 affects cardiovascular function as the pace of walking changes. METHODS: Forty-nine college students (27 men, 22 women) were subjected to treadmill exercises without masks (Group I) and wearing masks (Group II). The body temperature, heart rate, oxygen saturation, and blood pressure were measured to determine the changes in cardiovascular function. These parameters were measured at rest (Control I), low-intensity (Control II), medium-intensity (Control III), and high-intensity (Control IV) before and after exercise. RESULTS: Significant differences in heart rate were observed between Control III and Control IV, and a significant difference in oxygen saturation was noted in Control IV. Significant differences in the exercise intensity change in Group II were as follows: Body temperature was Control IV compared to Control I and Control II, heart rate was Control III and Control IV compared to Control I and Control II, and Control IV compared to Control III. The heart rate was Control III and Control IV compared to Control I and Control II, Control IV for Control III, oxygen saturation was Control IV compared to Control I, blood pressure was Control II and Control III and Control IV compared to Control I, and Control IV compared to Control II. CONCLUSION: Exercising when wearing a mask affects the cardiovascular system. Therapists should consider the patient's condition when setting the exercise intensity. In particular, therapists should be more careful when setting the exercise intensity of patients with cardiovascular disease.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1993년도 춘계학술대회
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• pp.116-119
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• 1993

In this paper, we implemented a pulse wave type oximeter system that continuously measure the of oxyhemoglobin saturation of the arterial blood(SaO2) and pulse rate with non-invasively. We use the transmission type and reflection type transducer for comparison the percentage of hemoglobin oxgen saturation. The light Iron the two kind of LEDs is transmitted through the tissue, then received by a single photodiode with alternatively. By the phase sensitive detection circuit, the output of the photodiode is separated in to red and near infrared signal. We calculated a ratio of light transmittance between two kind of LEDs, and then, it is applied to the oxgen saturation coefficent calculation formular.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2001년도 추계종합학술대회
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• pp.349-352
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• 2001

본 논문에서는 1400nm 대역에서 이득을 갖는 TDFA의 증폭 특성과 과도응답 특성을 이론적으로 해석하였다. 수치모델은 밀도반전의 형성과정, 여기파워, 증폭기를 따라 변화하는 신호파워를 포함한다. 본 이론해석의 결과는 광섬유증폭기의 이득 포화와 복구시간을 예측할 수 있게 해주고, 펌핑율과 포화 율이 이득의 포화와 복구시간에 미치는 영향을 예측할 수 있게 한다.

• 한국광학회지
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• 제1권2호
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• pp.162-168
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• 1990

내경이 2.1mm인 Pyrex 모세관을 사용하여 길이가 150mm인 도파형 이산화탄소 레이저를 제작하였으며, 공진기내에 임의의 손실을 가할 수 있는 ZnSe 손실판을 설치하여 공진기의 내부손실에 따른 출력변화를 여러 방전조건에 대해 측정하였다. 본 실험에 Rigrod 이론을 적용하여 내부손실에 따른 출력변화를 예측했으며 실험치로부터 포화출력 및 불포화 이득계수를 구할 수 있었다. 방전전류와 혼합기체의 유입률이 증가함에 따라 포화출력은 증가하며, 불포화 이득계수는 감소하는 경향을 볼 수 있었다.