• Industrial Engineering and Management Systems
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• 제14권2호
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• pp.122-128
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• 2015

The purpose of this paper is to propose an appropriate evaluation scheme for improvement activities, based on a simple model comprising cash inflow by sales as well as variable and fixed cost expenditures. The paper distinguishes capacity surplus and capacity shortage situations, and examines economic benefits gained by yield increase improvement and capacity increase. The paper then proposes a basic rule of thumb for economic evaluation of improvement activities. The logic is simple but useful in practice, being conducive towards improvement activities under current economic conditions with uncertainties.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2002년도 춘계학술대회
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• pp.257-262
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• 2002

There are two methodologies to increase transport capacity of railway. The one is to invest railroad equipment or vehicles, and the other is to improve operation efficiency through optimization. All of these is intended to increase transport capacity by improving line capacity So far, we treat line capacity as the criteria for evaluating investment alternatives or for restricting tram frequencies, and this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that change dynamically according to operational condition, so there is a need of new line capacity estimation system. The Purpose of this paper is to present a new line capacity estimation system based on the probability simulation and its applications.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 춘계학술대회 논문집
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• pp.122-127
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• 2002

There are two methodologies to increase transport capacity of railway. The one is to invest railroad equipment or vehicles, and the other to improve operation efficiency through operation optimization. All of these is intended to increase transport capacity by improving line capacity. So far, we treat line capacity as the criteria for evaluating investment alternatives or for restricting train frequencies, and this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that change dynamically according to operational condition, so there is a need of new line capacity estimation system. The Purpose of this paper is to present a new line capacity estimation system based on the probability simulation and its applications.

• 대한안전경영과학회지
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• 제4권3호
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• pp.167-175
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• 2002

There are two methodologies to increase transport capacity of railway. One is to invest railroad equipment or vehicles, and the other is to improve operation efficiency through optimization. All of these is intended to increase transport capacity by improving the line capacity. So far, we treat the line capacity as the criteria for evaluating investment alternatives or for restricting train frequencies, and this criteria is calculated statical and experimental numerical formula. But, line capacity has special attribute that changes dynamically according to operational conditions, so there is a need of new line capacity estimation system. The Purpose of this paper is to present a new estimation system of line capacity based on the probability simulation and its applications.

• 사물인터넷융복합논문지
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• 제8권4호
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• pp.17-23
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• 2022

이동통신사 주도의 LPWA(Low Power Wide Area) 기반 IoT 기술은 NB-IoT와 LTE Cat.M1이 상용화되어 서비스되고 있다. LPWA 기반 IoT에 대한 서비스 요구사항이 증가되면서 이러한 서비스 가입자도 증가하고 있는 상황이다. 서비스 초기에는 NB-IoT 및 LTE Cat.M1을 수용하기 위한 기지국 용량에 이슈가 없었으나, 가입자 증가로 하나의 셀에서 수용하기 위한 용량이 부족해지는 문제가 발생하고 있다. 이러한 Active UE 용량 문제는 지속적인 증가로 인한 과부하와 일시적인 증가로 인한 과부하 문제가 발생할 수 있다. 본 논문에서는 기지국에서 NB-IoT 및 LTE Cat.M1 단말의 일시적인 증가로 인해 발생 하는 LTE 접속제어 채널인 RRC(Radio Resource Control) Active UE 용량 부족 및 기지국 과부하 문제를 해결하기 위한 방안을 제시한다. 제시한 방안은 이동통신의 셀 분할 및 추가 기지국 투자 없이 셀 용량을 증대 시킬 수 있는 방안을 제시함으로써, 증가하는 IoT 단말을 수용해 서비스 성능을 개선시킨다.

• The Korean Journal of Physiology
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• 제14권1호
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• pp.7-13
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• 1980

In the previous experiment, authors have shown that during the latter half of estrous cycle there was an increase in plasma testosterone level in the rats stimulated with hCG. To determine the physiologic significance of elevated plasma testosterone, changes of the plasma concentrations of TeBG and testosterone following hCG stimulation were analyzed in the rats having a regular 5 day cycle. The rats were divided into three groups; the control, the rats stimulated with single hCG on the day of proestrus and stimulated with hCG throughout the entire cycle. Blood samples were obtained once a day for an estrous cycle and analyzed for the binding capacity of TeBG using ammonium sulphate precipitation method and testosterone concentration by means of radioimmunoassay. Followings were the results; 1) There was no significant variation in the binding capacity of TeBG in peripheral blood during the estrous cycle of the control rats. 2) No cyclic variation in the binding capacity of TeBG was observed in the rats stimulated with single hCG on proestrus. although the levels tended to be higher in the rats with stimulation than in the control rats. 3) Continual stimulation of hCG produced a marked increase in the binding capacity of TeBG especially on the day of metaestrus. 4) The changes in the plasma level of testosterone followed the same basic pattern seen in the TeBG binding capacity. 5) From above results, the followings were suggested. a. hCG related increase of the binding capacity of TeBG is probably secondary to a modest increase in estrogen as well. b. hCG related increase of plasma testosterone in female rats is not entirely due to excess production rather in part due to decreased metabolism induced by the rise in TeBG. c. It seems likely that most of elevated testosterone shown in the rat stimulated with hCG is bound to TeBG and only small portion is unbound form which influence cellular activity. It is rather possible that an increase in TeBG could augment estrogen activity.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 추계학술대회 논문집
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• pp.407-414
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• 1999

Sand drain as a vertical drainage is widely used in soft ground improvement. Recently, sand, the principal source of sand drain, is running out. A laboratory model test was carried out to utilize gravel as a substitute for sand. Though which the characteristics of gravel are compared to those of sand for engineering purpose. According to the test, the settlement was found to be smaller in gravel drain than in sand drain. The increase in bearing capacity by gravel rile explains the result. The clogging effect was not found in gravel column. As a result, it is assumed that gravel is relatively acceptable as a drainage material. Gravel material seems better than sand material in bearing capacity and it is found that bearing capacity is larger when gravel is used as compaction pile than as drain from in-situ test on bearing capacity. Increase of bearing capacity with gravel pile means an effect of composite ground by stiffness of gravel material. It can lie supposed to use gravel pile instead of sand pile in view of consolidation effect and bearing capacity.

• 국제물리치료학회지
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• 제2권2호
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• pp.339-343
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• 2011

The purpose of this study is to see the effect of functional electrical stimulation on forced vital capacity and alternating motion rate in children with spastic cerebral palsy. This study divided 20 children with spastic cerebral palsy into two groups; functional electrical stimulation treatment group and control group. Functional electrical stimulation treatment group had 20min per day treatment three times a week for four weeks and the control group did not have any treatment. Before and after intervention, this study measured forced vital capacity and alternate motion rate(/peo/,/teo/) for all children. Forced vital capacity showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). Alternate motion rate showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). This result shows that functional electrical stimulation affected the ability of the children with spastic cerebral palsy who have decreased breathing and phonation capability.

• Journal of the Korean Wood Science and Technology
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• 제33권6호통권134호
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• pp.38-45
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• 2005

본 연구는 다섯 종류의 서로 다른 형태의 목재 대 목재 결합부를 제작하여 각 결합부 그룹의 강도 성능 증가를 살펴보았다. 가장 높은 강도 성능 증가를 보인 그룹은 동일 단면 손실을 고려한 소경 볼트를 사용한 결합부 그룹이었고, 이어서 합판을 삽입한 결합부 그룹, 접착제를 볼트에 도포한 결합부 그룹, 그리고 마지막으로 고무판을 삽입한 결합부 그룹 순으로 나타났다. 이들 여러 형태의 결합부 그룹은 전체적으로 기존의 결합부 형태에 비해 최소 약 10% 이상의 강도 성능 증가를 보였다. 이 결과는 새로운 고 성능 결합부 개발에 다양한 형태로 응용이 가능할 것으로 판단된다. 하지만, 추가적인 작업으로 인한 시공상의 어려움과 추가적인 작업을 통해 얻을 수 있는 강도 성능 증가의 정도와 경제적인 이점 등을 종합적으로 고려해서 각 구조물에 적합한 결합부 형태와 재료를 선택해야 할 것으로 판단된다.

• 상하수도학회지
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• 제26권2호
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• pp.191-199
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• 2012

Rainwater harvesting systems (RWHS), one of measures for on site rainwater management, have been promoted by laws, regulations and guidelines and have been increased. However, more evaluation of economic feasibility on RWHS is still needed due to seasonal imbalance of rainfall and little experiences and analysis on design and operation of RWHS. In this study, we investigated tank capacity of RWHS to secure economic validity considering catchment area and water demand, which is affected by building scale. Moreover, sensitivity analysis was performed to examine the effect of design factors, cost items and increase rate of water service charge on economic feasibility. The BCR (benefit cost ratio) is proportional to the increase in tank capacity. It is increased steeply in small tank capacity due to the effect of cost and, since then, gently in middle and large tank capacity. In case of 0.05 in the rate of tank volume to catchment area and 0.005 in water demand to catchment area, BCR was over one from the tank capacity of 160 $m^{3}$ taking into account of private benefits and from the tank capacity of 100 $m^{3}$ taking into account of private and public benefits. Sensitivity analysis shows that increase of water demand can improve BCR values with little cost so that it is needed to extend application of rainwater use and select a proper range of design factor. Decrease of construction and maintenance cost reduced the tank volume to secure economic validity. Finally, increase rate of water service charge had considerable impact on economic feasibility.