• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.174-182
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• 2014

To monitor the wind-induced responses of buildings, conventional real-time kinematic (RTK) methods based on two global positioning system (GPS) receivers (e.g., a reference and a rover) are widely applied. However, these methods can encounter problems such as difficulty in securing and maintaining a space for a reference station. With the recently developed virtual reference station (VRS)-RTK approach, the position of a structure can be measured using only a rover receiver. In this study, to evaluate the applicability of VRS-RTK methods in monitoring the lateral structural responses of frame structures, we performed free vibration tests on a one-story frame model (the first natural frequency of 1 Hz) and a three-story frame model (the first natural frequency of 0.85 Hz). To assess the reliability of the displacement and acceleration responses measured by the GPS, we performed a concurrent measurement using laser displacement sensors and an accelerometer. The accelerometer results were consistent with the GPS measurements in terms of the time history and frequency content. Furthermore, to derive an appropriate sampling rate for the continuous monitoring of buildings, the errors in the displacement responses were evaluated at different GPS sampling rates (5, 10, 20 Hz). The results indicate that as the sampling rate increased, the errors in the displacement responses decreased. In addition, in the three-story model, all modal components (first, second, and third modes) could be recorded at a sampling rate of 20 Hz.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.11a
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• pp.89-94
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• 2004

Up to now a lot of the study on ship collision avoidance systems has proceeded actively. However the frequency of ship collision accidents didn't decreased. If there is collision risk in close quarters situation none the less manouvering ship for collision avoidance according to the system, only use of TCPA and DCPA as input factor for collision risk decision is not useful to avoiding collision action. For the recent 5 years by the analysis of first observation distance about approaching ship in domestic collision accidents, nearly $45\%$ of accidents is close first observation less than 2 miles. Therefor it is essential part for safety navigations to study for collision avoidance action in close encounter. In this paper, as foundation study of supporting collision avoidance manoeuvring for navigators, we proposed ship collision avoidance support model in close quarters situation through analysis of collision accidents for effective getting rid of the causes.

• Asian Oncology Nursing
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• v.9 no.2
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• pp.155-162
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• 2009

Purpose: The purpose of this study was to investigate the of laughter therapy on depression, anxiety, and stress among patients underwent radiotherapy. Methods: Participants in the study were comprised of 60 breast cancer outpatients who received radiotherapy. Thirty-one of the patients were assigned in the experimental group and the other 29 patients made up the control group. Laughter therapy was consisted of the delivery of information and active motion resulting in laughter. We provided laughter therapy 4 times for 2 weeks. Each session lasted 60 min. The experimental group received laughter therapy intervention as a group. An average attendance frequency per person was 2.7. To evaluate the effect of laughter therapy, the degrees of depression and anxiety were measured by Hospital Anxiety and Depression (HAD) and stress was measured by the Brief Encounter Psychosocial Instrument (BEPSI). Data analysis included a 2-test, t-test, and Fisher's exact test using SPSS 12.0 and SAS 8.0. Results: There was significant decrease in the degrees of depression, anxiety, and stress in the experimental group compared to those in the control group (p<.01, p=.04, and p<.01, respectively). Conclusion: This study provides evidence that laughter therapy is an effective intervention in improving depression, anxiety, and stress in breast cancer patients.

• Journal of the Korean Society of Safety
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• v.31 no.2
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• pp.104-111
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• 2016

Our nation has experienced remarkable growth over the half a century. Nonetheless, there is still much room for improvement in the area of Environment, Health and Safety (EHS). In particular, frequency and severity of industrial accidents did not considerably improve compared to the economic and social progress we made. The main objective of this research is to analyze what plans and actions are required for companies to promote industrial safety by 1) fostering functional competencies of EHS staffs and 2) effectively and proactively responding to rapidly changing EHS environment. For this research, EHS staffs from five large companies in Korea were surveyed. Most respondents indicated that one of key expertise required by EHS staffs is capabilities to effectively deal with changes to various domestic and international EHS-related laws and regulations. Furthermore, a predominant number of respondents commented that it is imperative for EHS staffs to have a broad knowledge of business management. As for internal issues that EHS staffs encounter within their organizations, many pointed out that their EHS vision is not sufficiently shared throughout the organization, and that the rules of leadership are critical in solving this issue. On the other hand, the survey respondents also raised an issue of limited EHS-related investments due to slow economy. As a solution, they proposed ways to align EHS organization's performance with the company's performance. Based on this survey, issues and solutions for EHS organizations were identified. Results of this research can benefit companies that plan to newly establish or further expand EHS organization.

• Journal of the Korean Home Economics Association
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• v.44 no.5 s.219
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• pp.21-33
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• 2006

The purpose of this study were 1) to analyze customer relationship management(CRM) based on the online customer experiences by product types (i.e., men's, women's, casual, sports wear), 2) to analyze CRM based on the off-line customer experiences by product type, and 3) to examine customer purchase behavior of fashion products and internet usage behavior by product types. Survey and 1:1 interview were conducted from January 13th to May 16th, 2005. Six consumers from each brand (i.e., 3 loyal customers and 3 general customers) in a total of 24 customers were selected from each product type. For the data analysis, content analysis and descriptive statistics (i.e. frequency) were used. Among the key study findings first, as a result of the on-line CRM experience, the customers of men's wear preferred receiving customized information through e-mail or SMS service. The customers of sports wear preferred receiving a different level of information and participating in customized product service. Second, as a result of the off-line CRM experience, the customers of men's wear need to be encouraged to join a membership at a sales encounter and the customers of women's wear preferred receiving quick information of new products and participating in a design development planning of the merchandising process. Third, the purchasing behavior of the customers of women's wear are influenced mostly by the salesperson and the store atmosphere when they purchase clothes and the customers of men's wear are price-sensitive. The results of this study can be used when fashion brands perform strategic planning and decision making on CRM.

• The Bulletin of The Korean Astronomical Society
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• v.42 no.2
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• pp.48.3-49
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• 2017

Interplanetary space of the solar system contains a large number of dust particles, referred to as Interplanetary Dust Particles (IDPs) cloud complex. They are observable through meteors and zodiacal lights. The relative contribution of possible sources to the IDPs cloud complex was an controversial topic, however, recent research (Yang & Ishiguro, 2015 and references therein) suggested a dominance of cometary origin. In this study, we numerically investigated the orbital evolution of cometary dust particles, with special concerns on different evolutionary tracks and its consequences according to initial orbits, size and particle shape. The effect of dust particle density and initial size-frequency distribution (SFD) were not decisive in total cloud complex mass and mass supply rate, when these physical quantities are confined by observed zodiacal light brightness and dust particle SFD at 1 au. We noticed that, if we assume the existence of fluffy aggregates discovered in the Earth's stratosphere and the coma of 67P/Churyumov-Gerasimenko, the required mass supply rate decreases significantly. We also found out that close encounters with planets (mostly Jupiter) are the dominating factor of the orbital evolution of dust particles, as the result, the lifetime of cometary dust particles are shorter than Poynting-Robertson lifetime (around 250 thousand years). As another consequence of severe close encounters, only a small fraction of cometary dust particles can be transferred into the orbit < 1 au. This effect is significant for large size particles of ${\beta}$ < 0.01. The exceptional cases are dust particles ejected from 2P/Encke and active asteroids. Because they rarely encounter with Jupiter, most dust particles ejected from those objects are governed by Poynting-Robertson effect and well transferred into the orbits of small semimajor axis. In consideration of the above effects, we directly estimated probability of mutual collisions between dust particles and concluded that mutual collisions in the IDPs cloud complex is mostly ignorable, except for the case of large sized particles from active asteroids.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.441-444
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• 2008

This paper describes the development of a circularly polarized microstrip antenna, as a part of the Circularly Polarized Synthetic Aperture Radar (CP-SAR) sensor which is currently under developed at the Microwave Remote Sensing Laboratory (MRSL) in Chiba University. CP-SAR is a new type of sensor developed for the purpose of remote sensing. With this sensor, lower-noise data/image will be obtained due to the absence of depolarization problems from propagation encounter in linearly polarized synthetic aperture radar. As well the data/images obtained will be investigated as the Axial Ratio Image (ARI), which is a new data that hopefully will reveal unique various backscattering characteristics. The sensor will be mounted on an Unmanned Aerial Vehicle (UAV) which will be aimed for fundamental research and applications. The microstrip antenna works in the frequency of 1.27 GHz (L-Band). The microstrip antenna utilized the proximity-coupled method of feeding. Initially, the optimization process of the single patch antenna design involving modifying the microstrip line feed to yield a high gain (above 5 dBi) and low return loss (below -10 dB). A minimum of 10 MHz bandwidth is targeted at below 3 dB of Axial Ratio for the circularly polarized antenna. A planar array from the single patch is formed next. Consideration for the array design is the beam radiation pattern in the azimuth and elevation plane which is specified based on the electrical and mechanical constraints of the UAV CP-SAR system. This research will contribute in the field of radar for remote sensing technology. The potential application is for landcover, disaster monitoring, snow cover, and oceanography mapping.

• Proceedings of the KSRS Conference
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• 2008.10a
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• pp.344-347
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• 2008

Ocean surface waves may be modified by ocean current and their observation may be severely distorted if the observer is on a moving platform with changing speed. Tidal current near a sill varies inversely with the water depth, and results spatially inhomogeneous modulation on the surface waves near the sill. For waves propagating upstream, they will encounter stronger current before reaching the sill, and therefore, they will shorten their wavelength with frequency unchanged, increase its amplitude, and it may break if the wave height is larger than 1/7 of the wavelength. These small scale (${\sim}$ 1 km changes is not suitable for satellite radar observation. Spatial distribution of wave-height spectra S(x, y) can not be acquired from wave gauges that are designed for collecting 2-D wave spectra at fixed locations, nor from satellite radar image which is more suitable for observing long swells. Optical images collected from cameras on-board a ship, over high-ground, or onboard an unmanned auto-piloting vehicle (UAV) may have pixel size that is small enough to resolve decimeter-scale short gravity waves. If diffuse sky light is the only source of lighting and it is uniform in camera-viewing directions, then the image intensity is proportional to the surface reflectance R(x, y) of diffuse light, and R is directly related to the surface slope. The slope spectrum and wave-height spectra S(x, y) may then be derived from R(x, y). The results are compared with the in situ measurement of wave spectra over Keelung Sill from a research vessel. The application of this method is for analysis and interpretation of satellite images on studies of current and wave interaction that often require fine scale information of wave-height spectra S(x, y) that changes dynamically with time and space.

• The Korean Nurse
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• v.28 no.3
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• pp.83-93
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• 1989

This study analysed marital comflicts, related factors, and adjustments to those conflicts described by urban Korean women. The purpose was to discover directions for resolution that would enhance the helpfulness of volunteers or prfessionals working with women in counselling settings. The investigator interviewed 20 married women, all mothers and housewives living in Seoul, attending marriage encounter programs and the Lifeline telephone counselling service. An interview schedule using six open-ended questiona guided the data colleciton which took place between May 31 and December 29, 1988. Content analysis of the data revealed, in order of reported frequency, the following areas of conflict: relationships between husband wife, relationships with children, relationships between the wife and her mother-in-Law, unsatisfied sexual needs, the husband's extra marital relationships, lack of self actualization and finacial matters. Analysis of the data suggested the following factors were related to the conflicts: reasons for marriage, traditional views about marriage and divorce including to accept a marriage arranged by the parents, the husband's traditonal attitude toward the sex role of the wife, the husband's patriarchical authoritarianism, and his attitude toward the wife;s empolyment outside the home. The women thought these conflicts severely affected their relationships within the famaily, particularly with their children. Literature suggests links with such poor parent-child-family relationships and adolescent or young people's social problems. Volunteers or professionals working with married women in counselling situation need to be conscious of the possibility of these conflict during assessment, and direct their guidance toward such conflict resolution. The researcher makes several suggestions which include the need for the husband to give emotional supports to his wife, to recognize the worth of housework, to share the work of the home, to fine ways to enhance the wife's self-actualization and to ease dreary housework routines by prviding modern appliances.

• Korean Institute of Interior Design Journal
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• v.21 no.6
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• pp.137-146
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• 2012

This study introduced the concept of Primacy Effect for the analysis of the observation characters by time so as to analyze the characters of information which the users observing the lobby in a public space get when they encounter the space. From the viewpoint that the first impression on any space can motivate the judgement of space and continuous activities, the time range with the observation characters which can be regarded as Primacy Effect was analyzed in the aspects of continuity and saccade. First, with the case of alignment by time on three times of continuous observation, the perception attributes of subjects were shown to be very different among one another depending on which time range was applied for alignment. Second, the subjects with low average value of continuous observation times were found to be relatively stable in "ii~iii time ranges" and the time range of "0~5.10 seconds" was known to be the time range of relatively stable analysis for the characters of subjects' primacy effect to be analyzed. Third, the change of the amount of acquired information could be examined concretely through the analysis of observation attributes by time range, and the time range of "iii time range" showed more stable changing characters than other time ranges. Fourth, in the "iii time range" set up as a proper time range for the analysis of primacy effect had higher average value of 3.9 times of observation frequency compared with 6 times of continuous observation. As a grand average, 6 times(19.3) of average observation value was between 3 times(21.3) and 9 times(16.9), which enabled to set up 6 times of continuous observation as the number of observation times for stable analysis of primacy effect.