• International Journal of High-Rise Buildings
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• v.9 no.2
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• pp.127-154
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• 2020

Disproportionate collapse triggered by local structural failure may cause huge casualties and economic losses, being one of the most critical civil engineering incidents. It is generally recognized that ensuring robustness of a structure, defined as its insensitivity to local failure, is the most acceptable and effective method to arrest disproportionate collapse. To date, the concept of robustness in its definition and quantification is still an issue of controversy. This paper presents a detailed review on about 50 quantitative measures of robustness for building structures, being classified into structural attribute-based and structural performance-based measures (deterministic and probabilistic). The definition of robustness is first described and distinguished from that of collapse resistance, vulnerability and redundancy. The review shows that deterministic measures predominate in quantifying structural robustness by comparing the structural responses of an intact and damaged structure. The attribute-based measures based on structural topology and stiffness are only applicable to elastic state of simple structural forms while the probabilistic measures receive growing interest by accounting for uncertainties in abnormal events, local failure, structural system and failure-induced consequences, which can be used for decision-making tools. There is still a lack of generalized quantifications of robustness, which should be derived based on the definition and design objectives and on the response of a structure to local damage as well as the associated consequences of collapse. Critical issues and recommendations for future design and research on quantification of robustness are provided from the views of column removal scenarios, types of structures, regularity of structural layouts, collapse modes, numerical methods, multiple hazards, degrees of robustness, partial damage of components, acceptable design criteria.

• Journal of the Korean Operations Research and Management Science Society
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• v.42 no.3
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• pp.51-69
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• 2017

TVarious studies in different industries have proven the effectiveness of nanotechnology, which is considered as a representative technology that makes lives faster and more convenient and economical. However, as nanomaterials are tiny, consumers are concerned on whether they can do any physical harm. Therefore, based on the perceived usefulness and ease of use from the generally used Technology Acceptance Model (TAM), this study added additional variables including perceived risk. Moreover, this study introduced three kinds of trust (institution, people, and technology trust) as moderating variables, which can reduce the negative effect of perceived risk. Based on the analysis using the Structural Equation Model, we determined that perceived usefulness and ease of use positively influenced the intention to adopt nanotechnology products. Thus, when consumers regarded nanotechnology products as efficient and convenient, they showed increased intention to adopt the technology. Furthermore, perceived risk negatively affected the intention to adopt nanotechnology products, that is, when customers' perceived risk increased, the adoption intention of nanotechnology product decreases because of the potential risk from nanotechnology. On the one hand, the negative effect of perceived risk on adoption intention decreased when trust in nanotechnology washigh and when consumers highlytrust experts or administrators. On the other hand, trust in government, public institutions, and companies which produce nanotechnology products showed no significant moderating effect. This study is meaningful as it generalized TAM by applying the model to new nanotechnology products and extended existing studies by the addition of perceived risk and various trust factors to the model.

• Journal of The Korean Association of Information Education
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• v.20 no.6
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• pp.617-628
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• 2016

For the education on information, information appliances and operating systems of the information curriculum in elementary schools, precedent studies on the content structure of domestic and foreign curricula and etc. were compared and analyzed, and the ways of improvement and implications were examined. In addition, the necessity to select these contents, time of education, appropriateness of the selected contents were surveyed by professionals, and as the research results, the contents for the education on information, information appliances and operating systems in elementary schools were chosen, and achievement standards were set and proposed. The paper results can be used for the development of national level of elementary information curriculum and for the cultivation of elementary school students' key educational capacities. This paper has the limit that its results cannot be generalized because its analysis was based on the outcome surveyed only by some experts. Nevertheless, it is meaningful in that it specifically tried to analyze the appropriateness of the content achievement standards of the elementary information curriculum, and through which, it offers the information necessary for the stable management of elementary information curriculum and the improvement of elementary information curriculum.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.17 no.2
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• pp.55-62
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• 2017

Gaucher disease (GD) is an autosomal recessive lysosomal storage disorder caused by beta-glucosidase deficiency. An 18 month-old male with hepatosplenomegaly, anemia, thrombocytopenia, and growth retardation referred to our hospital. The patient showed neurological symptoms, such as supranuclear gaze palsy and developmental delay. Bone marrow biopsy performed to rule out malignancy and the results revealed no malignant cell; however, abnormal histiocytes suggesting storage disease was noted. Based on hepatosplenomegaly, bicytopenia and unexplained neurologic manifestations, enzyme activity and genetic analysis were conducted emergently with a strong suspicion of GD. Beta-glucosidase activity in leukocyte was decreased. GBA sequencing to confirm the diagnosis revealed compound heterozygous pathogenic variants (i.e., c.754T>A, c.887G>A), both previously reported as the cause of neuronopathic GD. Under the diagnosis of type 3 GD, the patient immediately received enzyme replacement therapy (ERT). After 17 months of ERT, the size of spleen decreased, and hemoglobin and platelet count returned to normal. In addition, the activity of chitotriosidase and angiotensin converting enzyme decreased. However, myoclonic movement and generalized seizure occurred at the age of 19 months and antiepileptic drug was started. Other neurological deterioration including supranuclear gaze palsy and developmental delay also persisted. A new therapy to overcome neurologic problems should be developed for patients with type 3 GD.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.4
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• pp.364-370
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• 2015

Fixed restoration using implants for patients with posterior partial edentulism is generalized technique. As patient demands increase, the functional and esthetic implant restoration to achieve similar results to lost natural teeth is becoming an important issue. It is inevitable to use customized CAD/CAM abutments rather than ready-made abutments for the creation of implant prosthesis which closely resembles natural teeth. Using CAD/CAM abutment made it possible to obtain natural emergency profiles for posterior implant prostheses, ensuring more comfortable, efficient management of oral hygiene. However, keratinized gingiva with sufficient width and height for a natural emergence profile is required to use a large diameter CAD/CAM abutment which ensures stability and esthetics of hard/soft tissue around the implants. In this case, for esthetical and functional implant zirconia prosthesis, soft tissue graft was performed and customized CAD/CAM abutments were used following ridge augmentation, sinus graft and implantation. Satisfactory results were obtained functionally and esthetically through periodic clinical evaluation, and I hereby report this case.

• Korean Journal of Environment and Ecology
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• v.30 no.3
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• pp.369-375
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• 2016

This survey was conducted during March to April 2014 in the main stream and tributaries of Xe Pian and Xe Namnoy in order to investigate fish fauna in the Bolaven Plateau. Fish belonging to twenty eight species and eight families were collected from the main stream and tributaries of Xe Namnoy and Xe Pian during the survey period. Among them, Devario salmonatus, Poropuntius bolovenensis, Annamia sp., Sewellia elongata, Schistura bolavenensis, Schistura sp.1, Schistura sp.2, Schistura sp.3, Schistura sp.4, and Macronathus sp. were endemic species in the Bolaven Plateau, indicating a high prevalence rate of endemic species (35.7%) in the area. Meanwhile, Kottelat (2000, 2013) has been reported that four species of Poropuntius inhabit the Bolaven Plateau. However, the major morphic characteristics of Poropuntius species found in the Bolaven Plateau were mostly overlapped, except for the shape of their mouth. The young fish of Poropuntius (> 70 mm SL) have only generalized mouth while the of adult fish the shape of their mouth have two phenotype (narrow and broad). Therefore, it is assumed that Poropuntius species in the Bolaven Plateau has trophic polymorphism as the same species exhibits two different mouth shapes.

• Journal of Korea Water Resources Association
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• v.53 no.1
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• pp.1-13
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• 2020

The most common approach for computing engineering flow problems at high Reynolds number is still the Reynolds-averaged Navier-Stokes (RANS) computations based on turbulence models with wall functions. The recently developed generalized wall functions blending between the wall-limiting viscous and the outer logarithmic relations ensure a smooth transition of flow quantities across two regions. The performances and convergence properties of widely used turbulence models with wall functions that are applicable for turbulence kinetic energy (TKE), turbulent and specific dissipation rates, and eddy viscosity are presented through a series of near wall flow simulations. The present results show that RNG k-𝜖 model should be carefully applied with small tolerance to get the stable solution when the first grid lies in the buffer layer. The standard k-𝜖 and RNG k-𝜖 models are not sensitive to the selection of wall functions for both TKE and eddy viscosity, while the k-ω SST model should be applied together with kL-wall function for TKE and nutUB-wall functions for eddy viscosity to ensure accurate and stable boundary conditions. The applications to a backward-facing step flow at Re=155,000 reveal that the reattachment length is reasonably well predicted on appropriately refined mesh by all turbulence models, except the standard k-𝜖 model which about 13% underestimates the reattachment length regardless of the grid refinement.

• Journal of Distribution Science
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• v.14 no.2
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• pp.83-92
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• 2016

Purpose - The purpose of this study is to identify the relations among perceived organizational support, career planning, and subjective career success (career satisfaction and job satisfaction). In particular, this study focuses on the mediating effect on the career planning between perceived organization and subjective career success. The target cases are employees of a Korean branch of a global company (A), which operates formal career program to support a career development for employees. Research design, data, and methodology - The data were collected from December, 2014 to March, 2015. 211 out of 300 questionnaires were returned (response rate 70.3%). After the data cleaning, 209 questionnaires were used for the data analysis. These data were analyzed through descriptive statistics, correlation analysis, exploratory factor analysis (EFA), confirmatory factor analysis (CFA), and structural equation modeling (SEM). The whole process of the data analysis was accomplished using the SPSS 21.0 for windows and the AMOS 21 program. Results - The findings of the study are as follows: First, the better the organizational support is perceived, the higher career satisfaction and job satisfaction is. That is, the employees' career and job satisfaction is higher, when they feel themselves received more supporting. Second, perceived organizational support has a positive impact on employees' career planning. This result means that it is important to support employees in their career development. Third, career planning has a positive impact on career satisfaction, but not on job satisfaction. Lastly, it is verified that career planning has a mediating effect between the perceived organizational support and career satisfaction. Not only has the perception of an organizational support a direct impact on career satisfaction, but also an indirect impact through career planning. However, there is not an indirect relationship through career planning, just an direct relationship between the perception of an organizational support and job satisfaction Conclusions - Based on the findings of this study, the major conclusion of the study was as follows: The study provides theoretical values and practical implications for the fact that the differences of the subjective perception about organizational support exist among employees, and the differences have an impact on their career planning as well as subjective career success. Furthermore, some recommendations for workplace were suggested: The companies should support the career development for employees in organization level. Even though employment instability makes individual workers themselves to be responsible for their own career development, it is an important issue in organizational level that employees' career success could have positive effects on organizational development and success, as well. However, there is a limit in the study that analyzing results cannot be generalized due to the data from a single company. Some recommendations for future research are suggested: First, a comparative study should be conducted with other various companies. Second, a hierarchical analyzing model needs to be applied to substantiate how organizational context influences on subjective career success of employees.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.4
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• pp.94-99
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• 2009

The purpose of this study was to utilize hydroculture by the vital means of the improvement of indoor relative humidity. This experiment employed a search of the effect of Scindapsus aureus and Syngonium podophyllum that are generalized for hydroculture foliage plant by a difference of volume ratio, pot media and plants species. In the case of Scindapsus aureus, relative humidity was high for growth chamber in which plants presented as opposed to control growth chambers in which there were no plants. Although relative humidity was 25% in control chamber, there was an increase of 40% at a 2% volume ratio, 45% at a 3% volume ratio and 50% at a 5% volume ratio. The relative humidity of Syngonium podophyllum was 40% at a 2% volume ratio, 44% at a 3% volume ratio and 46% at a 5% volume ratio, while the control treatment was 25% relative humidity in hydroculture. Both the control treatment and hydroball pot in a hydroball container were high at first. As time progressed, artificial soil pots in water containers was similar when housed within the control chamber by about 45% relative humidity. Hydroball pots in water container had about 30% relative humidity. Ardisia pusilla of hydroball poIt in hydroball container had about 38% relative humidity.

• Journal of Preventive Medicine and Public Health
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• v.36 no.4
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• pp.303-313
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• 2003

General information is summarized, that is necessary to introduce a scientific assessment of the human health and exposure issue concerning dioxin and dioxin-like compound. Scientific literatures were reviewed to assess the background exposures to the dioxin-like compounds for normal residents. Epidemiologic studies were also reviewed to assess malignant and nonmalignant sweets of dioxins. In 1997, the International Agency for Research on Cancer classified 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a human carcinogen, primarily based on occupational cohort studies. The US Environmental Protection Agency made the same decision in it's Draft Dioxin Reassessment. Epidemiologic evidences point to a generalized excess of all cancers, without any pronounced excess at specific sites. Reported non-cancer effects included a range of conditions affecting most systems. Among them, chloracne, elevation in gamma glutamyl transferase(GGT), and alterations in reproductive hormones are related to TCDO, Other adverse outcomes, such as lipid concentrations, diabetes, circulatory and heart diseases, immunologic disorders, neurobehavioral effects, and developmental outcomes require further study before their respective relationships to TCDD can be more definitively assessed.