• Analytical Science and Technology
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• v.29 no.2
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• pp.65-72
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• 2016

This study presented an analytical method for detecting radium in soils using a liquid scintillation counter (LSC). The isotope ²²⁶Ra was extracted from soil using the fusion method and then separated from interfering radionuclides using the precipitation method. Radium was coprecipitated as sulfate salts with barium (Ba) and then converted into Ba(Ra)CO₃, which is soluble in an acidic solution. The isotope ²²²Rn, the decay progeny of ²²⁶Ra, was trapped in a water immiscible cocktail and analyzed by LSC. The pulse shape analysis (PSA) level was estimated using ⁹⁰Sr and ²²⁶Ra standard solutions. The figure of merit was the highest at PSA 80, while the alpha spillover was the lowest at PSA 80. The counting efficiency was 243 ± 2% in a glass vial. This analytical method was verified with International Atomic Energy Agency (IAEA) reference materials, including IAEA-312, IAEA-314, and IAEA-315. The recovery ranged from 60–82%, while the relative bias between the measured value and the recommended value was less than 10%. The minimum detectable activity was 2.1 Bq kg⁻¹ with dry mass 1 g, the background count rate of 0.02 cpm, the recovery rate of 70% and counting time of 30 min.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.281-307
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• 2016

The goal of this study was to verify that effectiveness of transformational leadership in impacting work engagement with the psychological contract breach among members of the organization and organizational anomie as mediating factors. The mediating effect of psychological contract breach and organizational anomie on the relationship between transformational leadership and work engagement was explored using a theoretical approach based on Social Exchange Theory, Social Information Processing Model and Job Demands- Resources Model. To avoid common method bias, the dependent variable was surveyed using employee peer review. 277 surveys were collected from 18 companies in diverse industries including manufacturing, distribution, and finance. The results of the analysis showed that transformational leadership has a significant positive effect on employees' work engagement, while having a significant negative effect on psychological contract breach and organizational anomie. In addition, psychological contract breach and organizational anomie were found to act as partial mediators in the relationship between transformational leadership and employees' work engagement. Overall, this study showed that if leaders at organizations can assist employees to overcome negative factors such as psychological contract breach and organizational anomie through transformational leadership, it is possible to improve employees' work engagement.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.437-445
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• 2013

This study was conducted to develop site index equations and to estimate productive areas of Quercus acutissima by ecoprovince in Korea using environmental factors. Using the large data set from both a digital forest site map and a climatic map, a total of 48 environmental factors including 19 climatic variables were regressed on site index to develop site index equations. Four to six environmental factors for Quercus acutissima by ecoprovince were selected as independent variables in the final site index equations. The result showed that the coefficients of determination for site index equations were ranged from 0.30 to 0.41, which seem to be relatively low but good enough for the estimation of forest stand productivity. The site index equations developed in this study were also verified by three evaluation statistics such as the estimation bias of model, precision of model, and mean square error of measurement. According to the evaluation statistics, it was found that the site index equations fitted well to the test data sets with relatively low bias and variation. As a result, it was concluded that the site index equations were well capable of estimating site quality. Based on the site index equations of Quercus acutissima by ecoprovince, the productive areas by ecoprovince were estimated by applying GIS technique to the digital forest site map and climate map. In addition, the distribution of productive areas by ecoprovince was illustrated by using GIS technique.

• Journal of Hospice and Palliative Care
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• v.18 no.2
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• pp.136-147
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• 2015

Purpose: This study was conducted to evaluate the effects of integrated palliative care intervention on quality of life in terminally ill patients. Methods: A comprehensive literature search was performed via PubMed, Cochrane Library CENTRAL, LWW (Ovid), CINAHL and several Korean databases. The main search strategy was to combine terms indicating palliative care intervention, presence of terminal illness and study design. Methodological quality was assessed using Cochrane's Risk of Bias for randomized studies and Risk of Bias Assessment tool for non-randomized studies. Data were analyzed by the Stata 10 program. Results: Eight clinical trials met the inclusion criteria with a total of 356 participants. Integrated palliative care interventions were administered for a mean of 6.5 weeks, 5.6 sessions and an average of 47.8 minutes per session. Effect sizes were heterogeneous, and subgroup analysis was done. Integrated palliative care interventions had a significant effect on quality of life (ES=1.83, P=0.018, $l^2=92%$), spiritual well-being (ES=0.78, P=0.040, $l^2=0$), depression (ES=0.86, P<0.001, $l^2=32$) and anxiety (ES=0.69, P=0.041, $l^2=71.1$). But integrated palliative care interventions had no significant effect on pain (ES=0.365, P=0.230, $l^2=69.8$). Conclusion: Results support findings that integrated palliative care interventions were helpful in lessening depression and anxiety and improving quality of life and spiritual well-being, however, the interventions did not assist pain management in terminal cancer patients. These findings suggest that various integrated palliative care interventions can assist terminal cancer patients with better quality of life in the socio-psycho-spiritual dimension.

• Journal of Chest Surgery
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• v.37 no.2
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• pp.113-118
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• 2004

The studies on cryopreserved arterial allograft have been focused on cooling methods, pre-treatment, cryoprotectant agents, and preservation temperature. But recently, several studies have reported that thawing methods also play an important role in the occurrence of macroscopic and microscopic cracks. This study was designed to investigate the cell injury after thawing, using a rabbit model to clarify the effect of thawing methods on cryopreserved arteries. Material and Method: Segments of the rabbit aorta were obtained and divided into 3 groups (n=60) according to whether the specimens were fresh (control, n=20), cryopreserved and rapidly thawed (RT) at 37$^{\circ}C$ (n=20), or cryopreserved and subjected to controlled, automated slow thawing (ST)(n=20). Cell damage was established using the TUNEL method and the morphological changes were also evaluated. Result: In the group that was rapidly thawed, the expression of TUNEL (＋) cells increased significantly more than in the slowly thawed group. In addition, the endothelial denudation, microvesicles and edema were significant in the rapidly thawed group compared with those changes in the slowly thawed group. Conclusion: Our study suggests that the rapid thawing method may be one of the major causes of cellular damage and delayed rupture in cryopresewed arterial allografts. The expression of TUNEL (＋) cells and structural changes were significantly low in the slowly thawed group, which might have contributed to the improvement of graft failure after transplantation.

• Korean Journal of Social Welfare
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• v.67 no.4
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• pp.279-299
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• 2015

This study examines the impact of Long-Term Care Insurance(LTCI) on family caregivers(especially focused on female household members) labor supply in South Korea. When public care and informal care are substitutes, LTCI will change allocation of time of family caregivers to spend more time to paid work. The impact of LTCI on labor supply depends on each country's institutional level of public care services. If public care can not substitute for informal care, labor supply of family caregivers will not rise significantly. The conclusions of vigorous empirical study from western countries' are incompatible and problem of endogeneity in terms of methodology has been raised consistently. The dataset of this study are used the third and ninth waves of Korea Welfare Panel. As a result, the introduction of LTCI had no effect on labor supply of household members. Robust findings suggest the positive effects of caregiving on labor market outcomes in simple comparison t-test, but not in fixed-effect regression. Compared with western countries, South Korea's public care services can be interpreted as a supplement to only part that remained at the level does not substitute informal care. These findings may suggest that if LTCI become much more prevalent in the future, senior citizens and family members will be able to choose the LTCI arrangement that best suits their needs.

• Korean Journal of Social Welfare
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• v.67 no.4
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• pp.153-180
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• 2015

The purpose of this study is to analyze the research articles on social work practice and discuss tasks of social work practice research in broadening and deepening social welfare knowledge body in Korea. First, this paper arranges critical discussion and results on social work practice research since the dawn of history in Korean social welfare research. Second, this paper examines 874 research articles published in Korean Journal of Social Welfare from the volume one in 1998 to the volume 66(4) in 2014. The appearance rate of social work practice research was 16.6%(145 articles), and empirical research in relation to social work practice was 40.5%(363 articles). Among 145 articles, 8.6% were practitioners, and the rest of them were in the position of professors. In addition, 26.2% were researches on program effectiveness, and 29.0% were researches on social worker. Third, this paper was interviewed 8 professors who majored social work practice. They evaluate the present states of social work practice research as positioning to boundary, crisis and confusion. Finally, this paper discusses the tasks of Korean social work practice research in order to more solidly develop the knowledge body of social work practice in Korea.

• Journal of Korean Society of Forest Science
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• v.98 no.6
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• pp.633-638
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• 2009

This study was conducted to develop stem taper equations and stem volume tables for Eucalyptus pellita and Acacia mangium plantations in Kalimantan, Indonesia. To derive a most adequate taper equation for the plantations, three models - Max & Burkhart, Kozak, and Lee models - were applied and their fitness were statistically analyzed by using fitness index, bias, and standard error of bias. The result showed that there is no significant difference between the three models, but the fitness index was slightly higher in the Kozak model. Therefore, the Kozak model was chosen for generating stem taper equations and stem volume tables for the Eucalyptus pellita and Acacia mangium plantations. The resulted stem volume table was compared to the local volume table used in Kalimantan regions, but no significant difference was found in the stem volume estimation. It is expected that the results of this study would provide a good information about the tree growth in abroad plantations and support a reliable decision-making for their management.

• Journal of Advanced Marine Engineering and Technology
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• v.41 no.4
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• pp.345-352
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• 2017

In this study, the effect of cryogenic liquefied natural gas leakage and loading on liquefied natural gas cargo hold is investigated to observe the performance of the polymer foam material that comprises the cryogenic insulation of the cargo hold. The primary barriers of liquefied natural gas carrier that are in contact with the liquefied natural gas will leak if damage is accumulated, owing to fluid impact loads or liquefied natural gas loading / unloading over a long period. The leakage of the cryogenic fluid affects the interior of the polymer foam, which is a porous closed cell structure, and causes a change in behavior with respect to the working load. In this study, mechanical properties of polyisocyanurate foam specimen, which is a polymer material used as insulation, are evaluated. The performance of the specimens, owing to the cold brittleness and the impregnation effects of the cryogenic fluids, are quantitatively compared and analyzed.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.311-324
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• 2006

In the Pohang-Gampo area, several diatomite beds occurred in mostly thinner than 1 m are embedded in the Pohang Formation of marine environment and the pyroclastic Eoil Formation. The diatomite from the Eoil Formation is constituting the high-grade ore altered slightly by diagenesis. In contrast, the diatomite intercalated within the upper horizon of the Yeonil Group is comparatively low-grade and highly altered in places. During diagenesis, an increasing of crystallinity of opal, i.e., the original mineral component of diatom, results in ultimately the mineral transition to quartz with accompanying a drastic change in morphology and texture of the altered diatomite. The diagenetic alteration appears to have undergone by way of the chemical diagenesis, which is largely controlled by degree of fluid contact, rather than burial diagenesis. For the diatomite from the Pohang-Gampo area, careful SEM observations, XRD, chemical analyses, and determination of specific surface area were done to identify the fossil species, mineral and chemical composition, and other physical properties in the view of assesment of grade and quality. The domestic diatomite ores are evaluated to be not good in grade and quality, compared to those of famous foreign localities. However, some diatomite deposits of marin,: origin from the Pohang Formation is constituting a peculiar clay-rich type, i.e., moler applicable to the special usage such as a manufacturing of lightweight brick. Because such a diatomite is frequently intercalated relatively as a thicker bed in the upper part of the Yeonil Group, a systematic and careful investigation should be done for the exploitation and development of an economic diatomite deposit of the moler type.