• Journal of Power System Engineering
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• v.4 no.2
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• pp.40-45
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• 2000

Some engineering materials are often known to have considerable spatial variation in their resisting strength and other properties. The objective of this study is to investigate the averaging effect and the applicability of extremal statistic for the statistical size effect. In the present study, it is assumed that the material property is a stationary random process in space. The theoretical autocorrelation function of the material strength are discussed for several correlation lengths. And, in order to investigate the statistical size effect, the material properties was simulated by using the non-Gaussian random process method. The material properties were plotted on the Weibull probability papers. The main results are summarized as follows: The autocorrelation function of the material properties are almost independent of the averaging length. The variance decreases with increasing the averaging length. As correlation length is smaller, the slope is larger. And also, it was found that Weibull statistics based on the weakest-link model could not explain the spatial variation of material properties with respect to the size effect satisfactory.

• Journal of the Korean Society of School Health
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• v.32 no.3
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• pp.152-164
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• 2019

Purpose: This study was a descriptive methodological study to develop protocols for school health practice to manage health problems of primary school students effectively. Methods: The protocols were verified by 12 experts and 10 health teachers, respectively, to secure a two-step content validity. Results: The main 8 health problems of primary school students were headache, abdominal pain, musculo-skeletal, respiratory, circulatory, ophthalmic, and oral-dental problems, and fever. The developed protocols consist of 8 algorithms, which are to help decision making in the course of assessing health problems and to identify and link related factors and associated symptoms, 8 school nursing records based on the Omaha classification system, and the list of 441 links between nursing assessment and nursing intervention. Conclusion: The use of the protocols is expected to make it easier for health teachers to apply the nursing process in solving the health problems of primary school students and supporting the rational decision making process, eventually improving the quality of primary school health. Repeated studies for protocol standardization as well as studies dealing with various health problems not included in the protocols should be performed for the development of school health practice protocols.

• Journal of the Korean Society of Safety
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• v.6 no.3
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• pp.27-34
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• 1991

This paper is for the properties of the oxidation-proof of the partially discharged and of the molecular motion on chlorinated PE Film. this paper also shows the properties of the molecular motion of the ${\gamma}$ ray irradiated PE Film. 1 In the surface of the PE Film enforce chlorination, C-Cl be distributed up to 10 $\mu$m deep. 2. In according to the development of the chlorination, the measure of crystalization decreased and cross link occured. 3. Chlorination PE Film control the oxidation on ozone to occuratlon by partial discharge and it lost bonding chlorine. 4. in according to chlorination, ${\gamma}$ absorption in motion of CH2 main chain of PE drcreased by chlorine stbstitution.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.7 no.3
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• pp.285-290
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• 2006

In a Vehicle, Safety is the most important factor for drivers. It is well known that tire pressure lower than normal reduces the safety of the vehicle. In a consideration of active safety, tire pressure monitoring system is absolutely required. Tire pressure monitoring using in-tire pressure sensors with an RE data link have proven to be best approach to measuring tire pressure over the widest range of operating conditions. In this paper, we describe the parameters of TPMS, the characteristic of tire pressure and temperature compensation. These are the main factors to design the decision logic. We will show the guidelines for TPMS logic development considering environment variables and vehicle conditions.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.357_358
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• 2009

According to the 4th BPE(Basic Plan for long-term Electricity Supply and Demand), Electricity demand of Jeju island in 2012 will be reached to 682MW. Jeju island will be faced with severe shortage of electricty, also needed to find transport route to supply green energy which will be made from "Carbon free island" energy policy toward land at that time. For that reason, The plan which construct 400MW size HVDC connection line was decided for potential supply stabilization and transportation of green energy. KEPCO organized special construction office not only to observe the successful project completion which aims 2011 December but also to build up professional manpower. KEPCO is putting spur to the HVDC project these days. Construction site of converter stations has been already confirmed and contracts of cable, converter have done as per turn-key early this year. On this report, we would like to discuss about project scheme, main characteristics of system, and the furture progress plan of "Jindo~Jeju HVDC construction project expecially converter station part" which is being pushed by KEPCO.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.3
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• pp.155-162
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• 2018

Delta robots are usually used for industrial manufacturing, but heavy weight and expensive price have been obstacles to rapid propagation of robots in the field. The goal of this research is to make light-weight and price-competitive delta robots. To reduce the weight, we used plastic material for the arm link, and to reduce the price, we used a step-motor as the main actuator. First we formulated the equations of inverse kinematics for the designed delta robot and then verified these equations by using multibody-dynamics simulation. An algorithm of motion control was developed and applied to the motion-processing unit using a timer-interrupt of 8 milliseconds. Finally, we tested the performance of the new delta robot by checking its control of motion along line segments.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.471-481
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• 2017

The canonical transient receptor potential channels (TRPCs) constitute a series of nonselective cation channels with variable degrees of $Ca^{2+}$ selectivity. TRPCs consist of seven mammalian members, TRPC1, TRPC2, TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7, which are further divided into four subtypes, TRPC1, TRPC2, TRPC4/5, and TRPC3/6/7. These channels take charge of various essential cell functions such as contraction, relaxation, proliferation, and dysfunction. This review, organized into seven main sections, will provide an overview of current knowledge about the underlying pathogenesis of TRPCs in cardio/cerebro-vascular diseases, including hypertension, pulmonary arterial hypertension, cardiac hypertrophy, atherosclerosis, arrhythmia, and cerebrovascular ischemia reperfusion injury. Collectively, TRPCs could become a group of drug targets with important physiological functions for the therapy of human cardio/cerebro-vascular diseases.

• Journal of the Korean Society of Physical Medicine
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• v.13 no.3
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• pp.141-150
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• 2018

PURPOSE: This study was conducted to understand the adaptive responses of different modes of physical exercises utilizing skeletal muscle and the comprehensive relevance of AMPK signaling that can be activated by physical exercise as a potential molecular target in human health problems such as neuromuscular disorders (NMDs). METHODS: Most of the contents in this review article are based on recent publications concerning the main topics of interest. The reference literatures cited were obtained by basic searches of overseas academic databases such as PubMed and ScienceDirect using EndNote X7.8. RESULTS: The phenotypic adaptive responses of skeletal muscle during endurance- and resistance-based exercise training (ET and RT respectively) appear to be distinct. To explain the adaptive responses in each single mode of exercises (ET, RT) along with combined exercise training (CT), AMPK signaling is proposed as an important molecular link among those differential modes of exercise and a promising molecular target of NMDs. CONCLUSION: Based on the available evidence, intracellular AMPK signaling activated by diverse stimuli including physical exercise can be a potential and promising therapeutic target for the prevention, amelioration or cure of various human health problems including NMDs and may also be beneficial for physical rehabilitation and emergency situations that may elicit acute metabolic stresses.

• Journal of Soil and Groundwater Environment
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• v.22 no.3
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• pp.18-26
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• 2017

The increasing frequency of droughts has been increasing the necessity of utilizing subsurface dams as reliable groundwater resources in areas where it is difficult to supply adequate agricultural water using only surface water. In this study, we analyzed the current status and actual conditions of five agricultural subsurface dams as well as the effect of obtaining additional groundwater from subsurface dams operated as one aspect of the sustainable integrated water management system. Based on the construction methods and functions of each subsurface dam, the five subsurface dams are classified into three types such as those that derive water from rivers, those that prevent seawater intrusion, and those that link to a main irrigation canal. The classification is based on various conditions including topography, reservoir location, irrigation facilities, and river and alluvial deposit distributions. Agricultural groundwater upstream of subsurface dams is obtained from four to five radial collector wells. From the study, the total amount of groundwater recovered from the subsurface dam is turned out to be about 29~44% of the total irrigation water demand, which is higher than that of general agricultural groundwater of about 4.6%.

• Computers and Concrete
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• v.8 no.6
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• pp.693-715
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• 2011

The main object of this study is to evaluate the seismic response effects on a reinforced concrete building isolated by triple concave friction pendulum (TCFP) bearings. The site-response effects arise from the difference in the local soil conditions at the support points of the buildings. The local soil conditions are, therefore, considered as soft, medium and firm; separately. The results on the responses of the isolated building are compared with those of the non-isolated. The building model used in the time history analysis, which is a two-dimensional and eight-storey reinforced concrete building with and without the seismic isolation bearings and/or the local soil conditions, is composed of two-dimensional moment resisting frames for superstructure and of plane elements featuring plane-stress for substructure. The TCFP bearings for isolating the building are modelled as of a series arrangement of the three single concave friction pendulum (SCFP) bearings. In order to investigate the efficiency of both the seismic isolation bearings and the site-response effects on the buildings, the time history analyses are elaborately conducted. It is noted that the site-response effects are important for the isolated building constructed on soft, medium or firm type local foundation soil. The results of the analysis demonstrate that the site-response has significant effects on the response values of the structure-seismic isolation-foundation soil system.