• Journal of Information Management
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• v.37 no.4
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• pp.69-91
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• 2006

The purpose of this study is to improve the effectiveness and quality of web service by analyzing the web service problems and suggesting the solutions through the expert service quality evaluation from the point of view of users and website quality evaluation by measurement tools for a whole NDSL website. In case of website analysis, this study analyzed the website completeness of NDSL site and looked into the problem that users can judge by intuition during their use of the site, and evaluated the searchability and usability for web-based service quality evaluation by centering on the service quality of database quality items. After the results of this analysis, it appeared that there was not a big problem on the use. But after searching, several problems were found on loading rates, website completeness, user sensitiveness, the protection of private information, metadata completeness, website accessability, etc. And as a result of the evaluation of website service quality, it does not show the all satisfactory results in the function of search methods and search result printing, mark list and the items related to full-text in the part of searchability and usability. However, comparing with the results of other information organizations, it shows the similar level of quality.

• Journal of Korean Society of Forest Science
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• v.89 no.5
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• pp.576-584
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• 2000

The term 'greenways' is a fairly new one. The term greenways refer to linear corridors which set aside pieces of nature. The objective of this study was to find out the feasibility of developing greenways in Taegu. Sample of 446 trail users were asked to describe their use patterns and as well as their perceptions of the benefits and problems associated with trails through on-site interviews conducted during the months of July and August of 1999. Trail users in Taegu were predominately male(61%) and over half of the respondents used private vehicle to access to the study areas as compared to 2% of respondents used bicycle. Trail users responded that health & fitness and open space preservation were the two most important benefits, and the provision of trail access to disabled persons was ranked last. As problems at study areas, lack of interpretive information was the biggest problem followed by lack of drinking water, poor trail marking/signs and not enough information. Most(94.1%) of the trail users surveyed indicated that they would support greenways development and 96.8% of respondent would use after greenways development. Willingness to pay for developing greenways was assessed with hypothetical scenario. Average willingness to pay in the survey was 10,200 won as a tax. The development/application of greenways in Taegu would work best when establish a network of trails with environmentally sensitive manner.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.1
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• pp.74-89
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• 2015

The objective of this study is to present countermeasures for mitigation of flood damage with inundation analysis considering the effect of inland and river flood and prediction of flood inundation area, depth and time against emergencies caused by abnormal flood and local torrential rainfall. In this study, 2-D inundation analysis was fulfilled on the basis of river flood analysis applying to HEC-HMS and FLDWAV model and inundation analysis applying to SWMM model for the area of Shineum-dong, Gimcheon-si. Also expected inundation depth and area about probable rainfall of 100 and 200 years frequency were suggested. If expected inundation depth and flooding area is presented on the basis of this inundation analysis considering the effect of inland and river flood, it would be an important preliminary data to establish structural and nonstructural countermeasures for flood prevention. Also if flood risk map is prepared based on the result of inundation analysis, it would be useful to evacuate residents in high-risk area and regulate road and vehicle.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.2
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• pp.103-112
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• 2010

In sensor networks, because sensors are deployed in an unprotected environment, they are prone to be targets of compromise attack, If the number of compromised nodes increases considerably, the key management in the network is paralyzed. In particular, compromise of Cluster Heads (CHs) in clustered sensor networks is much more threatening than that of normalsensors. Recently, rekeying schemes which update the exposed keys using the keys unknown to the compromised nodes are emerging. However, they cause some security and efficiency problems such as single group key employment in a cluster, passive eviction of compromised nodes, and excessive communication and computation overhead. In this paper, we present a proactive rekeying scheme using renewals of duster organization for clustered sensor networks. In the proposed scheme, each sensor establishes individual keys with neighbors at network boot-up time, and these keys are employed for later transmissions between sensors and their CH. By the periodic cluster reorganization, the compromised nodes are expelled from network and the individual keys employed in a cluster are changed continuously. Besides, newly elected CHs securely agree a key with sink by informing their members to sink, without exchangingany keying materials. The simulation results shows that the proposed scheme remarkably improves the confidentiality and integrity of data in spite of the increase of compromised nodes. Also, they show that the proposed scheme exploits the precious energy resource more efficiently than SHELL.

• Korean Journal of Family Social Work
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• no.23
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• pp.5-42
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• 2008

This research utilized the Grounded Theory and Giorgi's phenomenological research method to analyze the experience of battered women who are maintaining a non-violent marriage relationship. Due to the low accessibility of subjects and the distinctiveness of the topic, I have selected 4 participants and conducted in-depth interviews. As for data analysis results, there were 5 superior component elements and 19 inferior component elements for the experience of maintaining a non-violent marriage relationship and these appeared according to time. Thus, it can be analyzed as follows: 'the vicious cycle stage of violence: caught in a trap,' 'stage of breakaway from vicious violence cycle: making the self-rescue measures,' 'entry to a new track: retrieval of autonomy,' 'stage of forming a non-violence track: preventing the recurrence of the violence,' 'stage of maintaining non-violent track: conversion to non-violent relationship.' This research result will be useful in seeking an effective social welfare intervention plan for successful non-violent relationship in order to help 50% of the battered women from family violence who wish to maintain marriage.

• Journal of the Korean Society of Child Welfare
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• no.36
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• pp.7-27
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• 2011

This study empirically examines the effects of after-school self-care on children's development. More specifically, we examine whether the level of after-school self-care experiences that a child had during the 4 to 6 grade period affects the levels of school achievement, internalizing problem behaviors, externalizing problem behaviors, and delinquent behaviors during the child's middle school years. The study utilized the data from the Korea Welfare Panel Study's 1st and 4th year child supplementary surveys. The results show that the level of after-school self-care experiences negatively affects children's school achievement and internalizing problem behaviors. The study finds that, as the level of after-school self-care experiences increase, school achievement decreases and internalizing problem behaviors increase. The effects of after-school self-care on school achievement and internalizing behaviors were statistically significant even after controlling for the other variables that are known to be important factors on child development including child, parent, and family characteristics. The findings suggest that there is an independent effect of the level of after-school self-care on school achievement and internalizing problem behaviors. We also provide policy implications of the study. The policy considerations for latchkey children should include not only increasing the quantity of after-school programs, but also paying attention to the need of child development support programs beyond basic protection and care.

• Journal of Legislation Research
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• no.53
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• pp.269-310
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• 2017

This article aims at the study on Improvement of legal System which is related to automated vehicles in the era of the 4th industrial revolution. Legal aspects of driving automation have two view points. One is to permit a automated vehicle, the other is to regulate the behavior of driver on the road. Signifying elements of the 4th industrial revolution are IoT, AI, big data, cloud computing etc. Automated vehicles are the imbodiment of those new ICT technologies. The vehicle management act(VMA) rules about vehicle registration and approval of vehicle types. VMA defines a automated vehicle as a vehicle which can be self driven without handling of driver or passenger. Vehicle makers can take temporary driving permission for testing and research the driving automation. Current definition of automated vehicle of VMA is not enough for including all levels of SAE driving automation. In the VMA must be made also a new vehicle safty standard for automated vehicle. In the national assembly is curruntly pending three draft bills about legislation of artificial intelligence. Driving automation and AI technologies must be parallel developed. It is highly expected that more proceeding research of driving automation can be realized as soon as possible.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.459-467
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• 2019

The landing gear is a component that requires a high degree of safety to protect the lives of rotary-wing aircraft and boarding personnel, absorbing the impact on transfer/landing and supporting the fuselage during taxiing and mooring on the ground. In particular, the wheel landing gear supporting the aircraft fuselage absorbs most of the shock from the ground through the shock absorber and tires. This ensures the safety of the pilot on board the aircraft and satisfies the operational capability of the soldiers between missions. During the operation of a rotary-wing aircraft, a number of piston pins, which are a component of the right main wheel landing gear, were found to be broken. Therefore, this study examined the root cause of the piston pin crack phenomenon found in the main wheel landing gear. For this purpose, various causes were identified from fracture surface analysis of a flight test. In particular, the possibility of cracking was analyzed based on the influence on the fastening torque with the drag beam component applied to the piston pin at the time of development. This ensures the fatigue life and structural integrity.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.10
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• pp.18-25
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• 2019

Recently, micro-grids based on a CVCF inverter have been replacing diesel generators to reduce CO2 emissions in island areas with the increase of renewable energy sources. Stable operation methods are also being researched. These micro-grids may cause energy sinking if the total output of renewable energy sources is larger than the total customer loads. In the case of energy sinking, the voltage of a CVCF battery could rapidly increase according to the condition of SOC, and blackout could occur in the micro-grid due to the operation of a protection device in a CVCF inverter. Therefore, this paper analyzes the operation characteristics of a CVCF-inverter-based micro-grid when energy sinking occurs and proposes a transient operation strategy to prevent shut-down of the CVCF inverter. A test device of a 30-kW CVCF-inverter-based micro-grid was implemented, and the transient operation characteristics for the energy sinking phenomenon are presented. The simulation results confirm that blackout can be properly prevented according to the conditions of SOC and voltage in a CVCF battery.

• Journal of The Korean Association For Science Education
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• v.39 no.4
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• pp.563-571
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• 2019

The purpose of this study is to analyze the safety contents presented in high school science textbooks of the 2015 revised national science curriculum. For these, we found safety contents in the inquiries and appendices of 63 science textbooks: integrated science, science inquiry experiment, physics I, II, chemistry I, II, biology I, II, and earth science I, II. We analyzed these safety contents using six safety factors based on the seven standards for safety education. The main results are as follows: First, 81(46.0%) inquiries among 176 curriculum inquiries contain safety contents, and these contents are mainly found in chemistry textbooks, and the least in 'science inquiry experiment' textbooks. Second, safety contents are found the most in 'laboratory safety rule', followed by 'safety symbol' and 'usage of protection equipment'. Third, the safety contents of appendices are mainly in 'laboratory safety rule' and 'accident treatment'. Based on these results of this study, it is concluded that these textbooks have problems; that there is a big difference in describing safety contents in each textbook; that these safety contents are not presented in detail and that the educational effect is reduced. Furthermore, the safety symbol is not standardized. We also discussed ways to improve the safety contents of science textbooks.