• Journal of Energy Engineering
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• v.28 no.3
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• pp.42-54
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• 2019

The solar and wind power is spreading as a means to $CO_2$ reduction, but it has the characteristics of the volatility depending on the weather changes. This article aims to estimate the additional integration costs in Korea electric system in response to such volatility of increasing solar and wind power generation, using Korea electric power trading analyzer(KEPTA). The analysis utilizes the statistics of "8th Basic Plan for Long-term Electricity Supply and Demand" and "Renewable Energy Plan 3020". As the results, integration costs will be estimated 13.94Won/kWh~32.55Won/kWh, consisting of 8.94Won/kWh as back-up costs, 1.03Won/kWh~4.45Won/kWh as balancing costs, and 3.97Won/kWh~19.16Won/kWh as grid-costs. These results suggest that when the integration costs are secured, Korea electric system will be expected in the stable situation. This article leaves the further studies with taking the technological development of solar and wind power generation, the introduction of energy storage system, and wholesale price of electricity into consideration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.7
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• pp.3127-3134
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• 2013

This paper presents the verified results from the examination of the control algorithm, logic composition, and vehicle condition of the engine that has been adapted for DME fuel. It introduces the development process of the control structure and the logic control based on control map and auto-code generation, and finally verifies the reliability and performance of the overall control. The control structure largely consists of the injection control part that implements driver demand into an engine net torque and the air control system part that satisfies characteristics of exhaust gas and power performance. The control logic is designed with feedforward and feedback control for each of its control functions for an enhanced response. Moreover, the control map of the feedforward controller is created by the use of an engine model created by test data of mass product diesel engine, and it was subsequently calibrated in the test process of the engine and vehicle state. A test mode was completed by attaching the developed controller to the vehicle, and a reduction in gas emission is confirmed by the calibration of EGR, VGT, and injection times.

• Journal of Information Technology Services
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• v.19 no.4
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• pp.31-47
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• 2020

Recently, as the COVID-19 has spread and prolonged worldwide, the 'Untact' society is becoming routinized, and various smart technologies are leading to the spread of the 'Ontact' culture. This is because the desire of consumers to purchase a product and use the service has increased while minimizing the direct contact. In order to quickly respond to this circumstance, the percentage of the companies which are adopting Chatbot in various fields such as orders, delivery, and inquiries is increasing and they are getting a positive result. However as the demand for building Chatbot increases dramatically, there are many confusions among the companies which want to introduce Chatbot to their system, due to the lack of professional technicians and difficulties in understanding AI technologies and how to build them effectively. I believe that in the post COVID-19 era, much more companies will adopt Chatbot, and this will intensify the problem. The purpose of this study was to derive the needs for a guide on the method of buiilding a Chatbot through considering the prior research on Chatbot and analysis of the recent surge in the use of Chatbot services related to COVID-19. There are implications to presenting 5 phases of universal Chatbot implementation methodology using the platform to the stakeholders who want to introduce Chatbot to their customer so that they can understand and build Chatbot more easily and use AI Chatbot actively in response to the POST COVID-19 era.

• Earthquakes and Structures
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• v.10 no.2
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• pp.329-350
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• 2016

A parametric study was conducted to investigate the seismic deformation demands in terms of drift ratio, plastic base rotation and compression strain on rectangular wall members in frame-wall systems. The wall index defined as ratio of total wall area to the floor plan area was kept as variable in frame-wall models and its relation with the seismic demand at the base of the wall was investigated. The wall indexes of analyzed models are in the range of 0.2-2%. 4, 8 and 12-story frame-wall models were created. The seismic behavior of frame-wall models were calculated using nonlinear time-history analysis and design spectrum matched ground motion set. Analyses results revealed that the increased wall index led to significant reduction in the top and inter-story displacement demands especially for 4-story models. The calculated average inter-story drift decreased from 1.5% to 0.5% for 4-story models. The average drift ratio in 8- and 12-story models has changed from approximately 1.5% to 0.75%. As the wall index increases, the dispersion in the calculated drifts due to ground motion variability decreased considerably. This is mainly due to increase in the lateral stiffness of models that leads their fundamental period of vibration to fall into zone of the response spectra that has smaller dispersion for scaled ground motion data set. When walls were assessed according to plastic rotation limits defined in ASCE/SEI 41, it was seen that the walls in frame-wall systems with low wall index in the range of 0.2-0.6% could seldom survive the design earthquake without major damage. Concrete compressive strains calculated in all frame-wall structures were much higher than the limit allowed for design, ${\varepsilon}_c$=0.0035, so confinement is required at the boundaries. For rectangular walls above the wall index value of 1.0% nearly all walls assure at least life safety (LS) performance criteria. It is proposed that in the design of dual systems where frames and walls are connected by link and transverse beams, the minimum value of wall index should be greater than 0.6%, in order to prevent excessive damage to wall members.

• Earthquakes and Structures
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• v.10 no.2
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• pp.367-388
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• 2016

Eccentrically braced frames (EBFs) represent an attractive lateral load resisting steel system to be used in areas of high seismicity. In order to assess the likely damage for a given intensity of ground shaking, fragility functions can be used to identify the probability of exceeding a certain damage limit-state, given a certain response of a structure. This paper focuses on developing a set of fragility functions for EBF structures, considering that damage can be directly linked to the interstorey drift demand at each storey. This is done by performing a Monte Carlo Simulation of an analytical expression for the drift capacity of an EBF, where each term of the expression relies on either experimental testing results or mechanics-based reasoning. The analysis provides a set of fragility functions that can be used for three damage limit-states: concrete slab repair, damage requiring heat straightening of the link and damage requiring link replacement. Depending on the level of detail known about the EBF structure, in terms of its link section size, link length and storey number within a structure, the resulting fragility function can be refined and its associated dispersion reduced. This is done by using an analytical expression to estimate the median value of interstorey drift, which can be used in conjunction with an informed assumption of dispersion, or alternatively by using a MATLAB based tool that calculates the median and dispersion for each damage limit-state for a given set of user specified inputs about the EBF. However, a set of general fragility functions is also provided to enable quick assessment of the seismic performance of EBF structures at a regional scale.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.5
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• pp.799-806
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• 2020

The rapid growth of smartphone-to-Internet of Things (IoT) connections and the explosive demand for data usage centered on mobile video are increasing day by day, and this increase in data usage creates many problems in the IP system. In a full-based environment, in which information requesters focus on information providers to receive information from specific servers, problems arise with bottlenecks and large data processing. To address this problem, CCN networking technology, a future network technology, has emerged as an alternative to CCN networking technology, which reduces bottlenecks that occur when requesting popular content through caching of intermediate nodes and increases network efficiency, and can be applied to military information and communication networks to address the problem of traffic concentration and the use of various surveillance equipment in full-based networks, such as scientific monitoring systems, and to provide more efficient content.

• Design & Manufacturing
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• v.11 no.1
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• pp.39-44
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• 2017

The domestic mold industry is composed of 6,560 small and medium sized mold companies as of 2015. The structure of mold industry centered on less than 10 people in the past has been improved in the direction of increasing number of medium and large scale companies with more than 20 competitors with global competitiveness and has maintained its position as the world's second largest mold exporter with global competitiveness. Nevertheless, the manpower structure and corporate competitiveness structure of the mold industry is very high, with the proportion of production manpower reaching 70% and shortage rate of 10% or more in order to respond to the orders of customers. However, the development base for new employees with technological skills required by the industrial field is poor, and the inflow of young people is very limited due to factors such as the avoidance of small and medium enterprises and production jobs. It is expected that the labor shortage of mold enterprises will be further increased in the future. In the mold industry, due to the characteristics of small quantity multi-product production corresponding to the demand of the consumer, many production processes are individually and independently carried out, resulting in low labor productivity, and the structural time required for the worker to increase the working time Due to limitations, the working hours per week of the employees are about 50 hours. The implementation of the working time reduction bill, which is recently promoted by the government, is a crisis factor. In order to cultivate the mold industry, it is necessary to expand the base of molds to meet the intensification of global competition, the convergence of technologies to actively respond to the restructuring of the industrial structure, and the response to the new industry, It is necessary to improve labor productivity through policies such as development and dissemination of system, and to secure price, delivery and quality competitiveness in global market.

• The Korean Journal of Pharmacology
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• v.19 no.1
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• pp.61-69
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• 1983

Hypothermia is an essential preparatory procedure for cardiac surgery, which lows the metabolic rate and myocardial oxygen demand. However, hypothermia itself is a stress enough to change the tonus of sympathoadrenal system, especially the cardiovascular responses to the catecholamines. It is reported that the positive chronotropic and inotropic response of catecholamines is exaggerated during hypothermia because of decreased norepinephrine uptake at the junctional cleft or decreased catecholamine metabolism. On the other hand, there are evidences of diminished catecholamines responses in low temperature ana further, interconversion of adrenergic receptors is also suggested. Present investigation was planned to observe the cardiovascular changes and its responses to catecholamines during surface hypothermia in cat. Healthy mongrel cats, weighing $2{\sim}3\;kg$, anesthetized with secobarbital(30 mg/kg), were permitted to hypothermia by external cooling technic. Esophageal temperature, ECG (lead II), heart rate, left ventricular pressure with dP/dt, carotid artery pressure and left ventricular contractile force were monitored with Polygragh (Model 7, Grass), and the respiration was maintained with artificial respirator (V 5 KG, Narco). Followings are summarized results. 1) Surface cooling caused progressive decrease of body temperature and reached $l8.8{\pm}0.8^{\circ}C$ and $16.9{\pm}0.6^{\circ}C$ in 120 and 150 min respectively, after immersion into ice water, and ventricular fibrillation was developed at $20.4{\pm}0.65^{\circ}C$. 2) Heart rate, blood pressure and myocardial contractility were decreased after initial increase as the body temperature falls. 3) Systolic and diastolicdd P/dt of left ventricular pressure were decreased and that the decrement of diastolic dP/dt was more marked. 4) On ECG, ST depression, Twave inversion and prolongation of PR interval were prominent in hypothermia, and moreover, the prolongation of PR interval was marked just prior to the development of ventricular fibrillation. 5) The cardiovascular responses to catecholamines, especially to isoproterenol, were suppressed under hypothermia.

• Journal of Genetic Medicine
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• v.5 no.2
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• pp.89-93
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• 2008

"Personalized medicine," the goal of which is to provide better clinical care by applying patient's own genomic information to their health care is a global challenge for the $21^{st}$ century "genomic era." This is especially true in Korea, where provisions for clinical genetic services are inadequate for the existing demand, let alone future demands. Genomics-based knowledge and tools make it possible to approach each patient as a unique biological individual, which has led to a paradigm-shift in medical practice, giving it more of a predictive focus as compared with current treatment oriented approach. With recent advancements in genomics, many genetic tests, such as susceptibility genetic tests, have been developed for both rare single gene diseases and more common multifactorial diseases. Indeed, genetic tests for presymtomatic individuals and genetic tests for drug response have become widely available, and personalized medicine will face the challenge of assisting patients who use such tests to make appropriate and wise use of genetic risk assessment. A major challenge of genomic medicine lies in understanding and communicating disease risk in order to facilitate and support patients and their families in making informed decisions. Establishment of a health care system with provisions for genetic counseling as an integral part of health care service, in addition to genomic literacy of health care providers, is vital to meet this growing challenge. Realization of the promise of personalized medicine in the era of genomics for improvement of health care is dependent on further development of next generation sequencing technology and affordable sequencing test costs. Also necessary will be policy development concerning the ethical, legal and social issues of genomic medicine and an educated and ready medical community with clinical practice guidelines for genetic counseling and genetic testing.

• Journal of the Korea Society of Computer and Information
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• v.16 no.12
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• pp.265-271
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• 2011

High-quality customized services demand was growing due to the increase of aging, extremely nuclear family, disaster vulnerable of society. Ambulance service is required of fast and professional rescue and emergency service because of preventable death rate such as acute diseases, cerebral and cardiovascular diseases, suicides, etc. was higher than in developed countries. First aid will be available using patients information when emergency occurs, before arriving at the hospital. And emergency department is equipped with that patient care can be prepared in advance, increase the efficiency of emergency care. We received a variety of complex emergency call using high social awareness of 119 number and propose an efficient emergency medical service advancement strategy building an integrated response system with relevant organization.