• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.861-867
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• 2019

$Li_4Ti_5O_{12}$ is a promising next-generation anode material for lithium-ion batteries due to excellent cycle life, low irreversible capacity, and little volume expansion during charge-discharge process. However, it has poor charge capacity at high current density due to its low electrical conductivity. To improve this weakness, porous $Li_4Ti_5O_{12}$ was synthesized by sol-gel method with P123 as chelating agent. The physical characteristics of as-prepared sample was investigated by XRD, SEM, and BET analysis, and electrochemical properties were characterized by cycle performance test, cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS). $Li_4Ti_5O_{12}$ synthesized by 0.01mol ratio of P123/Ti showed most unified particle size, high specific surface area, and relatively high porosity. EIS analysis showed that depressed semicircle size was remarkably reduced, which suggested resistance value in electrode was decreased. Capacity in rate performance showed 178 mAh/g at 0.2C, 170 mAh/g at 0.5C, 110 mA/h at 5C, and 90 mAh/g at 10C. Capacity retention also showed 99% after rate performance.

• International Area Studies Review
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• v.18 no.3
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• pp.147-173
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• 2014

The economic growth of China, an average of 9% as an external performance, has caused lots of side effects in the country. The social issues such as income gap, especially the wide gap between the rich and poor, and regional divide are the main cause of concerns that China's economic growth is not sustainable. It prompted the Chinese government to realize that institutional regulations on CSR are not optional but required to promote the sustainable development of corporations. In 2006, CSR was addressed for the first time in China, as the government established the November 5 Plan and revised "Company Law". The government garnered social attention by introducing CSR for the first time in November 5 Plan. Also, the government established December 5 Plan in 2011 to set a key goal as 'sustainable development' and reflect concrete measures for CSR in its corporate policy. In particular, Commercial Bank has a social responsibility to establish more concrete, forceful regulations than those of general corporations, as a financial intermediary. Thus, this study is aimed at exploring how the social responsibility of Commercial Bank is reflected in the Banking Act, the issues, and legislative directions on the social responsibility of Commercial Bank in China.

• Journal of Gastric Cancer
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• v.19 no.3
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• pp.301-314
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• 2019

Purpose: Peritoneal carcinomatosis in gastric cancer (GC) patients results in extremely poor prognosis. Malignant ascites samples are the most appropriate biological material to use to evaluate biomarkers for peritoneal carcinomatosis. This study identified exosomal MicroRNAs (miRNAs) differently expressed between benign liver cirrhosis-associated ascites (LC-ascites) and malignant gastric cancer-associated ascites (GC-ascites), and validated their role as diagnostic biomarkers for GC-ascites. Materials and Methods: Total RNA was extracted from exosomes isolated from 165 ascites samples (73 LC-ascites and 92 GC-ascites). Initially, microarrays were used to screen the expression levels of 2,006 miRNAs in the discovery cohort (n=22). Subsequently, quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analyses were performed to validate the expression levels of selected exosomal miRNAs in the training (n=70) and validation (n=73) cohorts. Furthermore, carcinoembryonic antigen (CEA) levels were determined in ascites samples. Results: The miR-574-3p, miR-181b-5p, miR-4481, and miR-181d were significantly downregulated in the GC-ascites samples compared to the LC-ascites samples, and miR-181b-5p showed the best diagnostic performance for GC-ascites (area under the curve [AUC]=0.798 and 0.846 for the training and validation cohorts, respectively). The diagnostic performance of CEA for GC-ascites was improved by the combined analysis of miR-181b-5p and CEA (AUC=0.981 and 0.946 for the training and validation cohorts, respectively). Conclusions: We identified exosomal miRNAs capable of distinguishing between non-malignant and GC-ascites, showing that the combined use of miR-181b-5p and CEA could improve diagnosis.

• Korean Journal of Biological Psychiatry
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• v.25 no.4
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• pp.118-124
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• 2018

Objectives Although impulsivity has long been thought as an important factor influencing suicidal behaviors, it is unknown whether impulsivity increases the risk of dying from suicidal behaviors and what specific component among constructs of impulsivity contributes to the risk of dying among suicide attempters. Methods To elucidate the association between impulsivity and medical lethality of suicide attempt among suicide attempters, we consecutively recruited 46 suicide attempters who visited an emergency room of a general hospital located in a metropolitan area, Seoul, Republic of Korea, due to suicide attempts and consented to participate in this study. Then we assessed medical lethality with the Beck Lethality Scale (LS) and impulsivity with the Korean version of the Barratt Impulsiveness Scale-11-Revised (BIS). Demographic variables were obtained from medical records and structured social work reports for suicide attempters. Results Although total scores of the BIS did not correlate with LS scores, only the scores of self-control, that is one of the Barrett's six theoretical constructs of impulsivity in which the higher score indicates less self-control and more impulsivity, had a significant positive correlation with scores of LS (p = 0.003). The association remained significant after adjusting for variables known to affect suicide lethality such as job status, recent alcohol consumption, diagnosis of depressive disorders, and having a plan for suicide (${\beta}=0.429$, p = 0.009). Conclusions Not impulsivity in general, but poor self-control, in particular, predicts lethal suicidal behaviors among suicide attempters. The degree of self-control should be evaluated when assessing patients with elevated suicide risk, and proper measures should be installed to prevent possible future lethal suicide attempts.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.5
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• pp.75-83
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• 2019

In order to fulfill the obligation to voluntarily reduce greenhouse gas emissions under the Paris Climate Agreement, the proportion of coal and nuclear power generation is reduced worldwide and national efforts are being made to spread renewable energy including solar power generation. Korea also intends to increase the proportion of renewable energy generation to 30~35% by 2040 by introducing laws and regulations. In addition, while the country is trying to apply solar power generation to sidewalks and roads, there is no research related to it in Korea. Therefore, as a precedent study to develop solar power generation roads, solar power generation concrete blocks applicable to sidewalks and plazas were developed and the applicability was evaluated by constructing them on the site. As a result of indoor experiment, compressive strength was measured by 25.5~35.7MPa and flexural strength was measured by 5.1~10.5MPa, which showed that all domestic standards were satisfied. However, the higher the unit cement amount, the lower the strength was measured according to the mixing of the broken fine aggregate. The absorption rate was 5.7%, which satisfied the domestic standard of 7% or less. As a result of the freeze-thawing test, the reduction rate of the compressive strength after 100 cycles was up to 6.3%. As a result of measuring the settlement amount after construction, the maximum of 2.498mm was measured and irregular settlement occurred in the overall area, which is because the resolution of the sand layer was poor during construction. Maintenance techniques of sidewalk concrete block and solar panel need to be established more efficiently through long-term operation in the further.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.3
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• pp.55-71
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• 2019

The purpose of this study is to propose an evaluation method to assess green environments of streetscapes to improve urban street green spaces in Jeonju City. Through a rapid assessment of urban street green spaces, we suggest an objective basis for expanding street green space as well as for adopting sustainable maintenance and improvement measures. We choose 12 sections of streetscapes (roads and sidewalks) to investigate existing street conditions which have more than four lanes and function as major road axes. Six large roads and six medium roads of Jeonju City center area are investigated as pilot assessment study sites. Site inventory checklists consist of environmental characteristics of streetscape, street tree status, and planting condition evaluation. Environmental characteristics of streetscapes are composed of physical and neighborhood factors. For instance, items for physical factors are types and width of road/sidewalks, paving materials, tree protection materials, and green strip. And surrounding landuse is a neighborhood factor. Assessment items for street tree status are street plant names (tree/shrubs/ground cover), size, and planting intervals. Planting condition evaluation items are tree shape, damage, canopy density, and planting types with existence of adjacent green space. Evaluation results are classified into three levels such as A(maintain or repair), B(greening enhancement), and C(structural improvement). In case of grade A, streetscapes have enough sidewalk width for maintaining green strip and a multi-layered planting(in large road only) with fairly good growing conditions of street trees. For grade B and C, streetscapes have a moderate level of sidewalk width with a single street tree planting. In addition, street tree growing conditions are appeared poor so that green enhancement or maintenance measures are needed. For median, only grade B and C are found as its planting growing foundations are very limited in space. As a result, acquiring enough sidewalk space is essential to enhance ecological quality of urban street green. Especially, it is necessary to have green strip with reasonable widths for plant growing conditions in sidewalks. In addition, we need to consider native species with multi-layer plant compositions while designing street green.

• Journal of the Korean Geosynthetics Society
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• v.18 no.1
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• pp.91-101
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• 2019

Recently, small-scale excavation like ground cavity restoration and buried pipe replacement works are being carried out in urban area, in order to improve living convenience. This paper describes experiment results on the ground reinforcement method that can reduce the buried pipe damage, when the differential settlement occurred due to poor compaction of ground below the buried pipe. Plate load tests were conducted to evaluate a reinforcement effect of ground using concrete mat and expansion mat in the ground below the buried pipe. The results showed that the stress reduction ratio by concrete mat and expansion mat according to the surcharge load was about 46%~48% and 39%~42%, respectively. Therefore, the differential settlement of the buried pipe and the ground deformation below the buried pipes were reduced by the reinforcement effect of the concrete mat and expansion mat. This means that it is possible to prevent a buried pipe damage due to underground cavity and ground subsidence, if concrete mat and expansion mat are reinforced in the ground below the buried pipe or on the ground between the buried pipes.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.39 no.3
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• pp.15-21
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• 2021

This study studied the value of the spatial organization of the temple and the form of the garden located in the Seojang area in the southwestern regions of China. The value of the Lama temple was looked into by examining the relationship between Lamaism and Lama temple through the spatial organiz ation, building arrangement, and garden of temples that served as the center of history, culture, and politics of the time in the process of converging Buddhism introduced through China's central districts and India with folk beliefs in Seojang through the poor environment. To this end, the value of the space and garden of the Lama temple was derived through the representative Lama temples, Potala Temple, Norbulingka Temple, and Dazhao Temple. First, due to the unique environment in which ice caps and green areas coexist, the representative Lama temples in Seojang, Potala Temple, Norbulingka Temple, and Dazhao Temple, are widely distributed in the form of leaning against valleys and mountain ranges based on folk beliefs and Buddhism's Jatabuli(自他不二) and mandala. the target sites are largely divided into upper and lower spaces. Second, the target sites are largely divided into upper and lower spaces. Buildings for worship are located in the upper space, and spaces for practice and garden are located in the lower space. The garden existed in two main forms. Third, the garden existed in two main forms. Located in the center of the practice space, the garden had an ideal structure to plant bo tree to escape from the two false obsession and go to a world of truth that is with the Buddha behind the world through practice like Sakyamuni, and there was a garden around the temple where meditation and exchange took place. Evergreen coniferous forests are mainly planted in the forests.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.148-159
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• 2021

This study focused on searching for optimal locations for general high schools by considering the minimum move distance and the maximum student capacity upon starting a common curriculum based on a high school credit system by taking Seoul as an illustration. The main results were as follows. First, the results from P-median showed that the students' average move distance was below 625m when more than 30% of general high schools offer the common curriculum courses. In addition, the results from MCLP indicated that it was possible to hold all the students. Second, although all the universities located in Seoul open the common curriculum courses, it would not be available to hold all students. On the other hand, when more than 20% of the universities open the courses, MCLP indicated that it was possible to hold the same capacity. In addition, the Office of Education should support moving to the universities offering courses for students affiliated with high schools located in the southeastern area of Seoul and in poor transportation areas. It is expected that by suggesting a problem solving framework regarding space with a spatial optimization method, the study results can be used as a basic data for selecting schools offering common curriculum courses.

• Research in Plant Disease
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• v.26 no.4
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• pp.256-263
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• 2020

Incidence of Fusarium wilt was surveyed in fields of summer radish in Gangwon province in Korea in 2018 and 2019. The disease started in early July and spread rapidly in hot summer of late July and August and in severe case, reached up to 80% in a field in Gangneung area. Symptoms in the seedling stage include poor growth and browning of internal tissue of root. During mid-growth, the leaves of diseased plant turned yellow over time, the surface of the roots changed from white to blackish, and the vascular tissues turned brown. A total of 23 isolates was obtained from the diseased plants and identified as Fusarium oxysporum f. sp. raphani by elongation factor-1α and intergenic spacer sequence analysis. Pathogenicity of the isolates was tested by artificial inoculation to the radish and other plants. All the isolates tested were pathogenic to radish plant, although there were differences in virulence on radish 11 cultivars. However, the isolates were not virulent to other plants except some cruciferous vegetables including Brussels sprouts, rocket, stock, and turnip. The results of pathogenicity test showed that it is necessary to rotate with crops other than cruciferous vegetables in order to prevent Fusarium wilt from radish fields.