• The Journal of Korean Institute of Communications and Information Sciences
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• v.42 no.3
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• pp.639-648
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• 2017

Electronic warfare systems for extracting information of the threat signals can be employed under the circumstance where the power of the received signal is weak. To precisely and rapidly detect the threat signals, it is required to use methods exploiting whole energy of the received signals instead of conventional methods using a single received signal input. To utilize the whole energy, numerous sizes of windows need to be implemented in a detector for dealing with all possible unknown length of the received signal because it is assumed that there is no preliminary information of the uncooperative signals. However, this grid search method requires too large computational complexity to be practically implemented. In order to resolve this complexity problem, an approach that reduces the number of windows by selecting the smaller number of representative windows can be considered. However, each representative window in this approach needs to cover a certain amount of interval divided from the considering range. Consequently, the discordance between the length of the received signal and the window sizes results in degradation of the detection performance. Therefore, we propose the weighted energy detector which results in improved detection performance comparing with the conventional energy detector under circumstance where the window size is smaller than the length of the received signal. In addition, it is shown that the proposed method exhibits the same performance under other circumstances.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.173-184
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• 2008

Development of an accident estimation model based on accident data can be made after accident occurrences. However, the taking of historical accident data is not easy, and there have been differences between real accident data and police-reported accident data. Also, another difficult shortcoming is that historical traffic accident data better consider driver behavior or intersection characteristics. A new method needs to be developed that can predict accident occurrences for traffic safety improvement in black spots. Traffic conflict decision techniques can acquire and analyze data in time and space, requiring less data collection through investigation. However, there are shortcomings: as existing traffic conflict techniques do not operate automatically, the analyst's opinion could easily affect the study results. Also, existing methods do not consider the severity of traffic conflicts. In this study, the authors presented traffic conflict decision criteria which consider conflict severity, including opposing left turn traffic conflict and cross traffic conflict decision criteria. In order to test these criteria, the authors acquired three signalized intersection images (two intersections in Sungnam city and one intersection in Paju) and analyzed the acquired images using image processing techniques based on individual vehicle tracking technology. Within the analyzed images, level 1 conflicts occurred 343 times over three intersections. Some of these traffic conflicts resulted in level 3 conflict situations. Level 3 traffic conflicts occurred 25 times. From the study results, the authors found that traffic conflict decision techniques can be an alternative to evaluate traffic safety in black spots.

• Korean Journal of Culture and Social Issue
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• v.16 no.3
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• pp.355-383
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• 2010

In this study, the effects of skill-utilization based underemployment on self-esteem and mental health were examined. Also the moderating effects of employment commitment and social support were verified. Data obtained by a longitudinally designed survey with the reemployed (N=153) after job loss were used. The skill-utilization based underemployment was measured in two ways. One is measured in the way that use objective data, the ratio of education - 'educational requirement for the current job' divided by 'individual educational attainment.' The other is measured in the way that use psychological and self-reported measure, two factors of overqualification - the absence of opportunity for growth (no-growth) and the occupational mismatch in educational attainment, skills and experiences (mismatch). The main effect revealed that the no-growth made self-esteem lower and mental health (GHQ-social maladjustment) worse. The significant interaction of the ratio of education and employment commitment indicates that the negative effects of underemployment measured by the ratio of education on mental health (GHQ-social maladjustment, GHQ-depression/anxiety) were greater for those perceiving low employment commitment than for those perceiving high employment commitment. The significant interaction of the ratio of education and social support indicates that the negative effects of underemployment measured by the ratio of education on mental health (GHQ-depression/anxiety) were greater for those perceiving low social support than for those perceiving high social support. The two moderators also interacted with the two factors of perceived overqualification. Employment commitment had significant interaction effects with the no-growth and the mismatch on self-esteem and mental health (GHQ-depression/anxiety), whereas social support had a significant interaction only with the no-growth on mental health (GHQ-depression/anxiety). The significant interactions show that employment commitment and social support function as buffers in reducing the negative effects of skill-utilization based underemployment on self-esteem and mental health.

• Explosives and Blasting
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• v.28 no.2
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• pp.76-85
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• 2010

In this paper, we present the result of an analytical investigation concerning the demolition range for the pre-weakening of load-bearing wall in explosive demolition. Pre-weakening of load-bearing wall is usually conducted based on field experience because reliable specifications or guidelines for the design of pre-weakening have not yet been established in Korea. This study is one of the efforts to develop such a reliable specification or guideline for the pre-weakening process. Hence, the focus of the study is on the estimation of pre-weakening range of load-bearing wall. For the purpose, a finite element analysis (FE analysis) was conducted, and a pre-weakening range of load-bearing wall was suggested based on the analysis result.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.2
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• pp.195-206
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• 2020

Although the national radiological emergency response system has been improved by incorporating lessons from the Fukushima nuclear power plant accident and recent domestic natural disasters, it has not fully incorporated these lessons. In addition, it cannot deal with a variety of aftermath of the radiological disaster. Even for the same disaster, the national emergency response system should comply with multiple domestic laws in our country. Furthermore, there are a few discrepancies between the articles of the domestic laws that the national radiological emergency response system should address. Therefore, this study investigates the characteristics of radiological disasters, examines articles on the domestic laws related to the national radiological emergency response system, and analyses the Japanese government's responses to the Fukushima nuclear power plant accident. Based on the results of the review, suggestions for the improvement of the national radiological emergency response system in terms of response organization and framework have been proposed in this study.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.7
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• pp.569-578
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• 2017

The purpose of this study is to investigate the effects of informational diversity-sensitive orientation on employee attitudes, focusing on the moderating effects of communication. Recently, diversity within organizations has intensified and the importance of diversity management within organizations is increasing. Diversity studies have focused on the variance of objective diversity characteristics, and have provided mixed results. In order to overcome limitations in the research, this study focuses on members' perception of diversity. To this end, the variable of informational diversity-sensitive orientation(IDSO) was used. Sample data is derived from 301 surveys of employees in firms located in South Korea. Results show that informational diversity-sensitive orientation(IDSO) had a positive effect on job satisfaction and organizational commitment. Regarding the moderating effect of communication, a positive moderating effect was exhibited only in co-worker communication, and differential influence derived from communication type. Based on the analysis results, we discuss research implications and directions for future research.

• Journal of the Korean Society for information Management
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• v.26 no.4
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• pp.319-336
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• 2009

Semantic web technology is the evolution of current World Wide Web including a machine-understandable knowledge database, ontology, it may be enable machine and people to work together. However, problems arise when we try to communicate with different data, which are annotated by different ontologies created by different people with different concepts. Thus, to communicate between ontologies, it needs to align between heterogeneous ontologies. When it is aligned between concept nodes of heterogeneous ontologies, one of main problems is a misalignment situation caused by false negative of automatic ontology mapping. So, in this paper, we present a new method to minimize the false negative error in the process of aligning concept nodes of different ontology.

• Journal of the Korea Society of Computer and Information
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• v.24 no.12
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• pp.151-155
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• 2019

The purpose of this study is to investigate the knowledge and performance ability of cardiopulmonary resuscitation (CPR) of physical therapist. A total of 105 physical therapists participated in this study. All participants were responded a self-administered method questionnaire to investigate the knowledge of CPR, and measured on their performance ability of CPR by Braden Pro application. We identified the performance ability of CPR and compared between educated and uneducated group. Among the 7 items on the knowledge of CPR questionnaire, educated group scored higher than uneducated group in Sequence of CPR, Ratio of compression and ventilation, Position of hands for chest compressions, Compression rate of chest and Ventilation volume. However, Depth of chest compressions and Airway maneuver were scored higher in uneducated group. The performance ability of CPR was not significantly different between two groups. However, Compression rate of chest was higher than guideline of CPR in both groups. There were inconsistent results between the knowledge and performance ability of CPR whether educated or not. This study suggests that it needs to provide repeated educations that improve knowledge and performance ability of CPR in physical therapists.

• Journal of Cadastre & Land InformatiX
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• v.47 no.2
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• pp.121-133
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• 2017

Technical regulations in the spatial information domain have been developed by a variety of independent organizations and raised inconsistent and overlapping problems with spatial information standards. Many research projects have been done to solve these problems but due to the difficulty of changing or modifying existing administrative regulations, almost nothing has happened for the harmonization. As a response to the fundamental problem, KATS (Korean Agency for Technology and Standards) recently switched the existing system to "trans- governmental participatory standard operation system" and the administrative change created an independent and consistent standard system in the Ministry of Land, Infrastructure and Transport. The Ministry, as a part of the effort, established its own KSDI(Korean Spatial Data Infrastructure) Standard system. From this context this paper presents a redefinition of technical regulation for the harmonization with spatial information standards, an association model between the standards and regulations, and a maintenance methodology to solve the fore-mentioned problems.

• Journal of Korean Elementary Science Education
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• v.18 no.2
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• pp.21-33
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• 1999

The purpose of this study was to develop an Instrument for the Measurement of Cognitive Conflict Levels of students who confronted with an anomalous situation in science teaming. Anomalous situation is generated when students' prediction is disconsistent with the observed fact. In this study, the researchers identified 4 components of cognitive conflict and developed three items for each component. The items were developed and revised by four pilot tests. In the first pilot test, 55 elementary school students participated in the test In the second pilot test, 88 students of the 5th and 6th grader participated in the test. The instrument of measuring cognitive conflict levels was given to the subjects right after demonstrating anomalous situation. For the demonstration, two different problem situations were developed: one was a pulley problem and the other was electric bulbs in parallel. Answered reasons for each items were analyzed to assess students' understanding on each items. In third pilot test, 125 elementary school students participated in the test. A factor analysis of the responses was carried out and reliability of the test was assessed by calculating internal consistency values. The items were finalized by three pilot tests. After 1 month after the third pilot test, researchers conducted the finalized test items to 323 students of the 5th and 6th grader. The final instrument showed moderate reliability (Cronbach-α 0.82∼0.87) and good content validity(0.93). A factor analysis of the response was carried out. 4 main factors completely coincided with 4 components that we supposed to be the conducts of cognitive conflict. The instrument can provide a means for both teachers and researchers to assess the cognitive conflict of a large number of students within a single class period. The results can be used by teachers to better understand the process of conceptual change of their students and to match instruction and materials accordingly.