• Journal of Biomedical Engineering Research
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• v.19 no.2
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• pp.119-128
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• 1998

This paper describes a filtering algorithm which employs apriori information of SPECT lesion detectability potential for the filtering of degraded projection images prior to the backprojection reconstruction. In this algorithm, we determined m minimum detectable lesion sized(MDLSs) by assuming m object contrasts uniformly-chosen in the range of 0.0-1.0, based on a signal/noise model which provides the capability potential of SPECT in terms of physical factors. A best estimate of given projection image is attempted as a weighted combination of the subimages from m optimal filters whose design is focused on maximizing the local S/N ratios for the MDLS-lesions. These subimages show relatively larger resolution recovery effect and relatively smaller noise reduction effect with the decreased MDLS, and the weighting on each subimage was controlled by the difference between the subimage and the maximum-resolution-recovered projection image. The proposed filtering algoritym was tested on SPECT image reconstruction problems, and produced good results. Especially, this algorithm showed the adaptive effect that approximately averages the filter outputs in homogeneous areas and sensitively depends on each filter strength on contrast preserving/enhancing in textured lesion areas of the reconstructed image.

• 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 Social Welfare Studies
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• v.47 no.3
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• pp.251-277
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• 2016

The purpose of this study was to examine the effects of adolescents' mobile phone dependency on depression and aggression and to identify mediating effects of parenting attitudes and peer relationships. This study used data from the 4th and 5th waves of 2010 KCYPS (Korean Children and Youth Panel Survey). Structural Equation Model(SEM) was conducted to examine the mediating effects of parenting attitudes and peer relationships. The results showed that adolescents' mobile phone dependency had positive effects on depression and aggression. In addition, the relationship between adolescents' mobile phone dependency and depression was partially mediated by parenting attitudes and peer relationships. The relationship between adolescents' mobile phone dependency and aggression was also partially mediated by parenting attitudes and peer relationships. Based on these findings, further suggestions are provided to reduce adolescents' depression and aggression by decreasing mobile phone dependency and improving parenting attitudes and peer relationships.

• Korean Journal of Social Welfare Studies
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• v.43 no.1
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• pp.59-87
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• 2012

The purpose of this study is to understand the effect of violence in sports on intention to sport continuance among female athletes and to analysis the mediating effect of depression and the difference groups according to help-seeking. In order to accomplish these purposes, this study surveyed from September to October in 2010. The final subjects in the analysis were 345 female athletes who are belong to school athletic team, professional team, business team, and national team. The data were analyzed with SPSS 18.0 and AMOS 10.0 for conducting multiple group analysis. The main results of this study are as follows; First, those who were suffered by emotional violence were 62.4%; those who are damaged by physical violence were 28.6% among the participants in this study. In case of intention to sport continuance, when measured by a rule of five, was average 3.15. 29.9% of the female athletes scored above the standard of depression. Second, depression turned out to have a partial mediating effect within the relationship where violence in sports has effect on intention to sport continuance. Third, between experimental and non-experimental group on help-seeking among female athletes, there was a statistically significant difference in the structural relationship. This means that help-seeking has moderating effect within the path of violence in sports affecting depression. Based on the results, this study suggested that there is a strong need for intervention for the both prevention and cure of the sports violence. It is necessary to develop preventive programs and coping strategies on female athletes' depression and intention to sport continuance.

• Journal of the Korean Society of Child Welfare
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• no.40
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• pp.109-137
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• 2012

The purpose of this study is to examine the effects of direct experience with school violence on internet game addiction and school adjustment focusing on the mediating effect of depression. A survey of 559 middle school students in Seoul, Gyeonggi Province, and Pusan was conducted. The data were analyzed using AMOS 18.0. The results are as follows. First, 43.9% of the study sample experienced school violence in the previous year. In terms of internet game addiction, 45.9% were identified to be potentially addicted, and 6.6% were considered to be addicted to internet games. Second, results from the structural equation model show that school violence has positive effects on depression and internet game addiction. Third, depression has a positive effect on internet game addiction and a negative effect on school adjustment. Fourth, internet game addiction negatively affects school adjustment. Based on these research results, the findings from this study suggest need for intervention programs targeted to prevent school violence, internet game addiction, depression, and school adjustment.

• Korean Journal of Social Welfare Studies
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• v.45 no.3
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• pp.127-150
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• 2014

The purpose of this study was to evaluate the effect of parenting stress on marital conflict in dual earner couples with children in early childhood. Actor and Partner Interdependence Model (APIM) was conducted in order to identify how parenting stress affect husband and wife, respectively and how this make the actor effect as well as the partner effect regarding the marital conflict. The research was conducted with 629 married couples from the forth wave of the Panel Study of Korean Children (PSKC) data. In order to examine the relationships between the variables and to evaluate the appropriateness of the research model, structural equation model was used. The results showed that the parenting stress had significant positive effect on the marital conflict. The partner effect of parenting stress was significantly positive. This result implies that the mutual dependence in dual earner couple's marital conflict and parenting stress should be considered in the process of intervention. In other words, to improve the effectiveness of intervention, practitioners should treat couples together rather than being focused on individuals.

• Journal of the Korea Convergence Society
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• v.10 no.11
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• pp.165-172
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• 2019

This study attempted to ascertain convergent influence on hopelessness and its association with academic burnout, anxiety, psychosocial stress and hopelessness among health college students. The subjects of this study were 214 health college students in J region, which were randomly selected. The survey period was from October 1, 2018 to October 31, 2018, and the data were collected using a self-administered questionnaire. Hopelessness was positively correlated with academic burnout, anxiety and psychosocial stress. As a result of the analysis of covariance structure, it was found that the higher academic burnout, the higher anxiety and the higher psychosocial stress tend to increase hopelessness. In conclusion, in order to lower the hopelessness of health college students, efforts to reduce academic burnout, anxiety and psychosocial stress are needed. The results of the analysis are expected to be used for educational counseling and guidance intervention to reduce the hopelessness of health college students. Further research is needed to investigate various additional factors related to the hopelessness of health college students.

• Korean Journal of Psychosomatic Medicine
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• v.24 no.1
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• pp.109-116
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• 2016

Objectives : This study aimed to investigate the effects of resilience on posttraumatic stress symptoms and dissociation and whether depression mediates the relationships between resilience and posttraumatic stress symptoms and dissociation. Methods : A total of 115 firefighters participated in the study. Data were collected via the Life Events Checklist, Impact of Event Scale-Revised, Dissociative Experience Scale, Beck Depression Inventory, and Connor-Davidson Resilience Scale. Structural equation modeling and path analysis were applied to estimate the relationships between resilience, depression, posttraumatic stress symptoms, and dissociation. Results : Greater resilience was associated with lower posttraumatic stress symptoms and dissociation, and the relationship between them was fully mediated by depression. Conclusions : Specific aspects of depression may help explain the relationships between resilience and posttraumatic stress symptoms and dissociation. Tailored prevention programs and treatments based on resilience and depression may prevent posttraumatic stress symptoms and dissociation in firefighters and improve treatments outcomes among firefighters with posttraumatic stress symptoms and/or dissociation.

• 한국노년학
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• v.38 no.4
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• pp.1127-1148
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• 2018

Care-stress among the dementia caregivers has been an important issue. The purpose of this study is to examine the effects of the dementia elderly's symptoms on the primary caregivers'care -stress. In addition, the moderators, the expert support and the family support, were used to examine the moderating effects between the symptoms and the care-stress. The data was obtained at 10 day-care facilities and services in Seoul, Gyeonggi and Busan province in South Korea. A total of 191 participants were analyzed. They were the spouses or the adult children of the dementia elderly who were diagnosed with dementia within five years. This study was conducted in multiple regression analysis. The main findings are as follows. First of all, the symptoms that the dementia elderly show were significantly associated with the primary caregivers' care-stress. Also, the interactive variable with the expert support was statistically significant. However, it was not significant with the family support. This means that only the expert support from doctors, nurses or social workers decreased the caregivers' care-stress. The implications of this study are 1) the necessities of the education that covers the specific symptoms of the dementia patients', 2) the extension of the supportive policies for caregivers' care-stress, 3) the necessities of more allocation of the dementia specialists in the practical settings and cooperative systems among the dementia specialists in various fields, and 4) the enhancement of the family function among families who have a dementia elderly as a family member.

• Journal of vocational education research
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• v.33 no.3
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• pp.57-81
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• 2014

The purpose of this study is to identify the latent classes depending on trajectories of intrinsic and extrinsic work values amongst college students and to test the effects of gender, socioeconomic status, academic achievement and career maturity on determining the latent classes. The results indicated that intrinsic and extrinsic work values, respectively, have two types of latent classes. The latent classes were defined as a increasing group(29.4%) and a slight decreasing group(70.8%) in intrinsic work values, a slight decreasing group(18.1%) and a increasing group(81.9%) in extrinsic work values. It was also found that the higher academic achievement levels were more likely to belong to the increasing group in intrinsic work values, male college students were more likely to belong to the increasing group in extrinsic work values, and the higher socioeconomic status were more likely to belong to the increasing group in extrinsic work values. The findings of this study can enrich future research into career counseling and education of college students and provide basic data for the strategies and intervention of career counseling. Both the implications and limitations of this study were also discussed, along with suggestions for future research.