• The Journal of Korean Institute of Communications and Information Sciences
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• v.40 no.8
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• pp.1588-1596
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• 2015

In the Internet of Things (IoT), resource-constrained devices such as sensors are capable of communicating and exchanging data over the Internet. The IETF standard group has specified an application protocol CoAP, which uses UDP as a transport protocol, allows such a lightweight device to transmit data. Also, the IETF recommended the DTLS binding for securing CoAP. However, additional features should be added to the DTLS protocol to resolve several problems such as packet loss, reordering, fragmentation and replay attack. Consequently, performance of DTLS is worse than TLS. It is highly required for lightweight devices powered by small battery to design and implement a security protocol in an energy efficient manner. This paper thus discusses about DTLS performance in the perspective of energy consumption. To analyze the performance, we implemented IEEE 802.15.4 based test network consisting of constrained sensor devices in the Cooja simulator. We measured energy consumptions required for each of DTLS client and server in the test network. This paper compares the energy consumption and amount of transmitted data of each flight of DTLS handshake, and the processing and receiving time. We present the analyzed results with regard to code size, cipher primitive and fragmentation as well.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.384-389
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• 2017

This study was conducted to investigate the patient and hospital characteristics that affect receiving and non-receiving blood transfusion for hepatoma embolization. We analyzed data describing 757 patients of the Health Insurance Review and Assessment Service's 2011 claims sample data. Chi-squared and logistic regression analysis was performed using STATA 12.0. Logistic regression analysis revealed that anemia (Odds ratio (OR)=9.544, 95% confidence interval (CI)=3.362-27.097), female (OR=2.186, Cl=l.240-3.854), age 65-74 (OR=0.506, CI=0.269-0.952), 1000 over bed (OR=0.053, CI=0.018-0.151), out-department (OR=0.211, CI=0.081-0.551), and 700-999 bed (OR=0.105, CI=0.036-0.304) were significant predictors of blood transfusion in tertiary hospitals. Additionally, anemia (OR=69.681, CI=8.545-568.246) and aged 75 or over (OR=0.112, CI=0.025-0.506) were significant predictors of blood transfusion in general hospitals. This research would expected to cost effective and preliminary data of blood transfusion quality.

• Korean Security Journal
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• no.60
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• pp.63-89
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• 2019

The purpose of this research is to examine the impact of the organizational fairness of court security team on organizational citizenship behavior through the mediating effect of self-leadership. The data for this research were collected from court security officials located in six metropolitan cities including Seoul from April 1 to May 3, 2019. After discarding thirty-eight cases with missing values and outliers, a total of 402 cases were analyzed using SPSS 22 and AMOS 22. The results showed that organizational fairness did not have a direct effect on organizational citizenship behavior. However, it was found that self-leadership affected organizational citizenship behavior positively, and organizational fairness had a positive impact on self-leadership. Therefore, organizational fairness had an indirect positive influence on organizational citizenship behavior through the mediating effect of self-leadership. The results of current research suggest that the supervisors of the court security teams should consider policy changes for improved treatment and working conditions of the security officials as well as educational programs aimed at promoting self-leadership which is shown to increase with organizational fairness and affect organizational citizenship behavior positively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.752-757
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• 2016

Machine to Machine (M2M) communications is communications between a business application and devices via a communication network without any direct human interaction. The aim of our research is to connect any M2M device with an M2M AS (Application server) through an IMS (IP Multimedia Subsystem) Network Core using a M2M Gateway, in order to develop an M2M Horizontal Services Platform over IMS. An IP Multimedia Subsystem (IMS) is an architectural framework defined by the wireless standards body of the 3rd Generation Partnership Project (3GPP) for delivering IP multimedia services to mobile users. This paper shows the design and implementation of a Horizontal M2M Network Services Platform over an IP Multimedia Subsystem (IMS) using the Message Session Relay Protocol (MSRP). We summarize the protocols and architectures that formed the basis for the creation of our architecture. We provide a detailed description of our architecture design, describing the call flow of the proposed architecture and the entities operating in each process. We also describe the design and implementation process detailing the different tools used, explaining the selection of each component and its importance; also how we designed and implemented the M2M gateway, M2M Application Server, Open IMS Core, business application and M2M devices.

• Journal of Life Science
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• v.19 no.8
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• pp.1119-1124
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• 2009

Hyperlipidemia has been reported to be associated with the development of fatty liver. Palmitic acid, a major saturated fatty acid, is involved in the development of diverse diseases. The activation of mitogen activated protein kinases (MAPKs), such as Jun N-terminal kinase (INKs) and p38 MAPK is implicated in the apoptosis in diverse cells. Thus, this study was conducted to investigate the effects of palmitic acid on apoptosis and its relationship between JNK and p38 MAPK in cultured rat hepatocytes. In the present study, palmitic acid (>50 uM) decreased cell proliferation and increased lactate dehydrogenase activity in hepatocytes, which was blocked by the treatment of SP600125 (a JNK inhibitor) and SB203580 (a p38 MAPK inhibitor). Indeed, palmitic acid decreased Bcl-2 expression but increased Bax expression in rat hepatocytes, which was blocked by the treatment of SP600125 and SB203580. In addition, palmitic acid decreased glutathione (GSH) content and increased lipid peroxide formation, which was blocked by the treatment of SP600125 and SB203580. Western immunoblotting analysis also revealed that palmitic acid increased JNK and p38 MAPK. In conclusion, palmitic acid induced apoptosis through oxidative stress via JNK and p38 MAPK activation in rat hepatocytes.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.168-174
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• 2014

It was conducted to evaluate the control efficacy of Bordeaux mixture on pepper anthracnose in vitro and in vivo. The suppressive efficacy of Bordeaux mixture on mycelial growth and spore germination of Colletotrichum acutatum was investigated on PDA, cellophane membranes and pepper fruits, respectively. Furthermore, its control value was evaluated on detached pepper fruits inoculated with C. acutatum by wound and non-wound inoculation method, and in fields. The mycelial growth of C. acutatum JC24 was inhibited by 90.0% on PDA amended with $937{\mu}g\;mL^{-1}$ of Bordeaux mixture. While the spore germination of C. acutatum JC24 was inhibited perfectly on cellophane membranes treated at $187{\mu}g\;mL^{-1}$ of Bordeaux mixture, that on fruits inoculated with the pathogen by wound inoculation and non-wound inoculation method was inhibited by 88.1% and 91.3%, respectively. Although the control value on fruits treated with $937{\mu}g\;mL^{-1}$ of Bordeaux mixture was 17.6% in wound inoculation method, it was 58.8% in non-wound inoculation method. In fields, when Bordeaux mixture was sprayed five times at 14 day-intervals, it showed 55.7% and 61.7% of control value in 2012 and 2013, respectively. We think Bordeaux mixture was able to use as an eco-friendly organic farming material to control pepper anthracnose based on the above-mentioned results.

• Journal of KIISE:Computing Practices and Letters
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• v.11 no.3
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• pp.235-245
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• 2005

The rapid development of computer network technology has brought the Internet as the major infrastructure to our society. But the rapid increase in malicious computer intrusions using such technology causes urgent problems of protecting our information society. The recent trends of the intrusions reflect that the intruders do not break into victim host directly and do some malicious behaviors. Rather, they tend to use some automated intrusion tools to penetrate systems. Most of the unknown types of the intrusions are caused by using such tools, with some minor modifications. These tools are mostly similar to the Previous ones, and the results of using such tools remain the same as in common patterns. In this paper, we are describing design and implementation of attacker-traceback system, which traces the intruder based on the multi-agent architecture. The system first applied SOM to classify the unknown types of the intrusion into previous similar intrusion classes. And during the intrusion analysis stage, we formalized the patterns of the tools as a knowledge base. Based on the patterns, the agent system gets activated, and the automatic tracing of the intrusion routes begins through the previous attacked host, by finding some intrusion evidences on the attacked system.

• Journal of the Korean Institute of Intelligent Systems
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• v.20 no.1
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• pp.54-59
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• 2010

This paper present to study the guidance system as localization technique using sensor fusion and line tracking technique using virtual line for AGV(autonomous guided vehicle). An existing AGV could drive on decided line only. And representative guidance systems of such guidance system are magnet-gyro guidance and wired guidance. However, those have had the high cost of installation and maintenance, and the difficulty of system change according to variation of working environment. To solve such problems, we make the localization system which is fused with a laser navigation and gyro, encoder. The system is robust against noise, and flexible according to working environment through sensor fusion. For line tracking of laser navigation without wire guidance, we set the virtual line in program, and design the driving controller based on difference of angle and distance between AGV's position and decided virtual line. To experiment, we use the AGV which is made by ourselves, and experiment the line tracking repeatedly on same experimental environment. In result, maximum distance error between decided virtual line and AGV's position was less than 49.93mm, and we verified that the proposed system is efficient for line tracking of actual AGV.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.10
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• pp.6114-6125
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• 2014

This paper analyzed the issues related to focus on farmers behaviors of energy saving facilities. This study conducted questionnaire and field surveys of controlled horticulture farmers and economic analysis using an IPA(Importance-Performance Analysis) matrix. According to the research results, the performance level was low on average ranging from 2.33 to 2.56 in a five point Likert-scale on greenhouse mandarin and grape-related facilities. On the other hand, the importance levels were high in the mean rating from 2.69 to 4.8. The results show that energy loss reduction of complementary facility and alternative energy supply support for low cost implementation are more important in terms of the respondents concerns than performance quadrant III. Therefore, it is important to provide financial support to energy-saving facilities to promote the use of energy efficiency improvement. In addition, the government should invest continuously in research and development.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.621-637
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• 2019

This study verifies the impact of emotional labor of online shopping mall call center counselor on customer orientation and the medium effect of job burnout. The study targets call center counselors from four companies that operate online shopping malls, and 271 copies are used for final data analysis. The results are as follows. First, deep action, a subfactor of emotional labor, has shown to have a significant positive effect on customer orientation. Second, the deep action of emotional labor has shown to have a negative effect on depersonalization and reduced personal accomplishment, while the surface action has a positive effect on job exhaustion and depersonalization. Third, deep action of emotional labor is found to increase customer orientation through depersonalization and reduced personal achievement, which are sub-factors of job burnout, while surface action of emotional labor is mediated by depersonalization, lowering customer orientation. The results of this study confirm that it is necessary to increase deep action and reduce job burn-out in order to improve customer orientation. Also, it is meaningful that the study verifies the role and the mediating effect of job burn-out.