• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.65 no.6
• /
• pp.979-986
• /
• 2016

At present, electric power industry around the world are being gradually changed to a new paradigm, such as electrical energy storage system, the wireless power transmission. Demand for ESS, the core technology of the new paradigm, has been growing worldwide. However, it is essential to estimate the optimal capacity of ESS facilities for frequency regulation because the benefit would be saturated in accordance with the investment moment and the increase of total invested capacity of ESS facilities. Hence, in this paper, the annual optimal mathematical investment model is proposed to estimate the optimal capacity and to establish investment plan of ESS facility for frequency regulation. The optimal mathematical investment model is newly established for each season, because the construction period is short and the operation effect for the load by seasons is different unlike previous the mathematical investment model. Additionally, the marginal operating cost is found by new mathematical operation model considering no-load cost and start-up cost as step functions improving the previous mathematical operation model. ESS optimal capacity is established by use value in use iterative methods. In this case, ESS facilities cost is used in terms of the value of the beginning of the year.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.24 no.9
• /
• pp.142-149
• /
• 2010

Interest in energy efficiency and savings have been rising internationally. For this reason, the domestic housing construction in the area of power equipment is being actively studied. Currently approximately 400,000 per year of domestic housing is being built. Applies to housing construction during the current transformer capacity low utilization and load factor has been applied has been designed. In other words, excessively high reserve capacity has been applied. According to this problem, initial facility costs and power losses will cause because transformer low utilization be appropriated. Thus, the energy efficiency drops. In this paper, analysis of past utilization of the housing transformer, and applying an appropriate demand factor has been analyzing the energy loss reduction. this analysis of current domestic conditions for the proper housing transformer scheme is to calculate the capacity.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.54 no.3
• /
• pp.139-143
• /
• 2005

Several methods have been proposed to mitigate the market power in foreign electricity markets. In this paper, Hirfindahl-Hirschman Index(HHI) and supply margin assessment(SMA) are compared based upon the Korean future markets. The results show that SMA is better than HHI to estimate market power because it can reflect congestion and capacity reserve effectively.

• Korean Journal of Community Nutrition
• /
• v.4 no.2
• /
• pp.254-259
• /
• 1999

노화는 모든 사람에게 공통적으로 일어나는 자연스러운 현상이다. 그러나 이에 따른 신체적인 변화는 각 개인에 따라, 그리고 한 개인 안에서조차 각종 장기별로 다양한 속도로 진행된다. 노년기의 생리적인 변화는 예비용량(reserve capacity)의 저하에 따라 외부의 스트레스에 대처하여 항상성을 유지하는 능력이 감소되어 나타나게 된다. 안정적 상태에서 기능수준에는 큰 변화가 없으나 활동상태의 기능 수준은 연령증가에 따라 상당히 저하되는 것을 보여준다. 노년기의 생리적 변화에 따라 직병에 대한 감수성은 증가하나 대다수의 만성퇴행성질환은 특정 병리현상에 의해 발생하며 노화가 직접적인 원인으로 작용하지는 않는 것으로 알려지고 있다.

• Proceedings of the KIEE Conference
• /
• 2002.07a
• /
• pp.392-394
• /
• 2002

전력시장에서의 적정 설비예비력을 확보하는 문제는 구조개편의 진행과 캘리포니아 전력비상사태 이후 더욱 더 중요성을 가짐에 따라 이에 대한 심도 있는 논의와 분석이 필요하게 되었다. 이런 이유로 현재 해외전력시장에서 활용중인 적정 설비예비력 확보방안들을 이론적 및 실증적인 방법에 의한 비교 분석을 통하여 한국전력시장에 적합한 방안을 모색하고자 한다. 본 논문에서는 특히 미국 PJM 전력시장 등에서 활용중인 용량의무 방식과 캘리포니아 시장에서 활용중인 시장의존방식을 중심으로 적정 설비예비력 확보방안을 간략하게 비교하고자 한다.

• Steel and Composite Structures
• /
• v.9 no.3
• /
• pp.223-237
• /
• 2009

The present research aims to develop a methodology to rapidly assess bridges with damage to the superstructure, caused by overheight trucks or lower-than-average overhead clearance. Terrestrial laser scanning and image processing techniques are combined with the finite element method to arrive at an analytical model which is more accurate, with respect to the complex geometrical aspects of the bridge in its damaged configuration. ""Virtual load testing"" may subsequently be carried out on this analytical model to determine the reserve capacity of the structure in an objective manner.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.06a
• /
• pp.339-342
• /
• 2006

The power outputs of renewable energy such as wind turbines and solar energy powers depend on natural sources. Accordingly, the power outputs of renewable energy is different from capacity rate at the time of peak load. Because of this gap, long term electricity power plan can have over-estimated reserve margin. So, this paper suggests the chronological approach to calculate the reliability assessment of renewable energy.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
• /
• v.22 no.2
• /
• pp.65-69
• /
• 2016

Background: The purpose of this study was to determine whether place running exercise that combines thoracic mobility exercise program increases pulmonary function of the 20s subjects. Method: Thirty subjects in their 20s were randomly assigned to on experimental group (n=15) or control group (n=15). Over the course of four weeks, the experimental group participated in place running exercise that combines thoracic mobility exercise program for 30 minutes three times per week and the control group participated in place running exercise and thoracoabdominal stretching exercise for 30 minutes three times per week. Subjects were assessed pre-test and post-test by measurement of pulmonary function Results: Our findings show that the experimental group had significant difference in expiratory reserve volume and vital capacity and maximal voluntary capacity (p<.05). In the comparison of the two groups, the experimental group had higher vital capacity and maximal voluntary capacity than the control group. Conclusion: In this study, the experimental group showed greater improvement in pulmonary function than the control group, which indicates that the place running exercise that combines thoracic mobility exercise program exercise is effective at increasing the pulmonary function.

• Journal of the Korean Society of Physical Medicine
• /
• v.6 no.3
• /
• pp.247-256
• /
• 2011

Purpose : The purpose of this study were to determine whether changes of position might effect the chest expansion and pulmonary function of the 20s men obesity. Methods : Thirty subjects with obesity(M:30, % fat>25.0) and thirty normal subjects(M:30, % fat<24.9) were participated in experiment. Subjects were assessed according to position changes(supine position, $45^{\circ}$ lean sitting position, $90^{\circ}$ sitting position) using chest length(chest length for resting, chest expansion) and pulmonary function (Tidal volume, Inspiratory capacity, Vital capacity, Inspiratory reserve volume, Expiratory reserve volume) by the CardioTouch 3000S(BIONET, USA). Repeated measure ANOVA was used to compare each region data of chest length and pulmonary function according to changes of position with obesity and normal subjects. Results : These findings suggest that the obesity can be appear to low chest expansion and pulmonary function than normal subjects on position method. In comparison of three experimental position, supine position was more low. Conclusion : This study showed position of the obesity appear low chest expansion and function of pulmonary volume than normal subjects, and thus it indicates that the pulmonary function of the obesity will be suggest objective respiratory data through the exercise program.

• Journal of Korean Neurosurgical Society
• /
• v.40 no.6
• /
• pp.434-440
• /
• 2006

Objective : The purpose of this study is to examine the influence of cranioplasty on dynamics of cerebral blood flow[CBF] and cerebrovascular reserve capacity[CVRC], and to investigate the usefulness of single photon emission computed tomography [SPECT] as a prognostic factor for neurological improvement after cranioplasty. Methods : Between March 2003 and December 2005, a prospective study was performed on 24 patients who had undergone total 25 cranioplasty operations. Cerebral blood flow velocities in the middle cerebral artery[MCA] and internal carotid artery[ICA] were obtained by transcranial Doppler ultrasonography[TCD]. The CVRC was assessed by SPECT in the natural state and after stimulation with 1g of acetazolamide. Neurological improvement after cranioplasty was compared between patients who showed hyperactivity to acetazolamide-activated SPECT [Group 1, n=7] and hypoactivity to acetazolamide-activated SPECT [Group 2, n=17]. These measurements were obtained two weeks prior to and two weeks after cranioplasty. Results : The blood flow velocities at the opposite site to the cranioplasty as well as at the cranioplasty site were significantly increased [P<0.05]. Compared with Group 2, there was significant increase in CBF and neurological improvement after cranioplasty in Group 1. Conclusion : Among patients with surgical bony defects, the patients who had normal reactivity of the CVRC showed a significant increase in CBF and neurological improvement after cranioplasty. The authors suggest that CVRC measurement prior to surgery may be an important prognostic factor for neurological improvement after cranioplasty.