• Structural Engineering and Mechanics
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• v.88 no.3
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• pp.209-220
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• 2023

This study investigates the effectiveness of tuned mass dampers (TMDs) in controlling vibrations in low-rise reinforced concrete buildings. It examines both linear and nonlinear behaviors of concrete structures subjected to strong ground motions from the PEER database. The research follows the ASCE 7-16 provisions to model structural nonlinearity. Additionally, the study explores the effect of varying TMD mass ratios on the performance of these systems in real-world conditions. The findings emphasize the importance of accounting for structural nonlinearity in low-rise buildings, highlighting its significant influence on the controlled response under severe seismic excitations. The study suggests including nonlinear analysis in seismic design practices and recommends customizing TMD designs to optimize vibration control. These recommendations have practical implications for enhancing the safety and effectiveness of seismic design practices for low-rise buildings.

• Journal of Korean Society on Water Environment
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• v.24 no.5
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• pp.523-532
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• 2008

A phase II site investigation and feasibility study was conducted at a military mortar shooting range near the demilitarized zone (Kyunggi, South Korea) to assess the extent of contaminants migration to the nearby Imjin river in which a flood control dam is under construction. The results showed that silty-clay soils around target areas were co-contaminated with heavy metals (Cd, Cu, and Pb) and explosives (HMX, RDX, and TNT). The total amount of contaminant was estimated to be 497.1 kg-RDX, 20.6 kg-HMX, 1.4 kg-TNT, 35.2 kg-Cd, 4,331 kg-Cu, and 5,115 kg-Pb, respectively. Both heavy metals and explosives were almost equally distributed on each soil particle size fraction. Neither subsurface soil samples nor ground water samples showed signs of contamination above the environmental criteria. The major migration route of contaminants was soil particles in surface run-off during rain at which a mass discharge rate of 30.0 mg-RDX/hour was observed.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2000.10a
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• pp.314-321
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• 2000

Excessive torsional behavior of asymmetric building structures is observed to be the main cause of the poor seismic performance. Concepts of current design provisions for torsion are based on the assumption that the strength of the lateral load resisting elements can be adjusted without changing their stiffness. This paper investigates inelastic torsional effects of multi-story high rise residential building in Korea on increase of strength demand and ductility of members using some methods published in literature. The methods analyze the reduction of strength and member ductility resulting from torsional mechanisms. This study shows that use of these concepts control inelastic torsion during preliminary seismic design of multi-story building of irregular plans.

• Structural Engineering and Mechanics
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• v.30 no.3
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• pp.297-316
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• 2008

This paper investigates the structural behavior of Korean traditional wooden structures on the basis of the structural analysis using the commercialized program, SAP 2000. All the structural systems were analyzed, and the rotational stiffness at each joint was inferred from the experimental result for a half scale model of Bongjeong-sa (a temple in South Korea). In addition, the artificial control of analysis parameters was prevented because the structural analysis was focused on the realization of the most exact structural behavior of real structures. The analysis was carried out for the horizontal and vertical static loads, and all the secondary members were excluded in the structural analysis. The obtained results show that the resisting capacity of the primary structural system is greater than that of the expanding structural system.

• Journal of the Korean Home Economics Association
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• v.44 no.8
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• pp.151-160
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• 2006

Consumers want to get healthful food which guarantee the aging control, anti-tumor, immunity-reinforcement, obesity prevention, beauty, prevention of adult disease and well-being. Because they want natural foods without food additives and environmental pollution which were used for convenience, we should develop the various food to guarantee the safety, wholesomeness and convenience. And so, we must study and identify basically the functionality and sanitation in foods to use practically. The companies should develop new products and corporate with universities and government. Because there are much more food informations, people believe unidentified information and continue wrong behavior such as food faddism. Consequently consumers should choose wisely their foods in consideration of their health, time, money and purpose.

• IE interfaces
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• v.13 no.4
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• pp.751-758
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• 2000

Situation awareness is defined as a person's perception of the elements of the environment within a volume of time and space, the comprehension of their meaning and the projection of their status in the near future. Situation awareness is important in attempting to evaluate human behavior in operating complex systems such as aircraft, air traffic control, and nuclear power plant systems. From the literatures this study reviews the relationship between situation awareness and numerous individual, system and environmental factors, and also reviews the methodologies for the empirical measurement of situation awareness applicable to Korea Next Generation Reactor (KNGR) design project. Attention, working memory, workload, stress, system complexity, and automation are presented as critical factors limiting operator's situation awareness. Mental models and goal-directed behavior are hypothesized as important mechanisms overcoming these limits. This study summarized hypothesized guidelines for interface design to improve situation awareness of reactor operators. Some of the guidelines should be tested in the KNGR evaluation experiments in the future.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.5
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• pp.35-43
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• 2014

The automobile industry requires technological innovations to reduce fuel consumption with the public interest in environmental conservation in recent years. Thus, the hybrid system is applied not only to passenger cars but also commercial vehicles. The purpose of this paper is to develop engine ECU_ILS to develop commercial hybrid vehicles. In order to develop the engine and vehicle, the dynamometer and exhaust gas analyzer is needed. However, a lot of time and cost are required. In contrast, the model-based development environment that can be applied to a variety of test conditions can reduce development time. Therefore, a HILS system environment that can consider the behavior of actual vehicles for evaluation of the control logic, fuel consumption and exhaust gas is required. This engine ECU_ILS system was developed in this study, can analyze parameter such as the fuel injection rate, fuel injection time, fuel consumption and exhaust gas like the actual vehicle test using map data. Also, this system is expected to be able to analyze the characteristic of vehicle behavior and the development of peripheral device in relation to engine and vehicles. This HILS system can be used to develop control strategies of commercial hybrid vehicle systems in the future.

• International Journal of Industrial Entomology and Biomaterials
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• v.38 no.1
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• pp.1-5
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• 2019

Bee's population is declining and disappearing at alarming rate. There are many factors responsible for declining the population of bees including diseases, natural enemies, environmental conditions and pesticides. Insecticides play its role dramatically for their population decline and neonicotinoid insecticides are critically important due to their wide application for pest control. Keeping in view of above problem, effect of neonicotinoid insecticides on olfactory learning behavior in Apis mellifera was observed using Proboscis Extension Reflex (PER) method. In this method, bees were harnessed in centrifuges tubes and feed on insecticides mixed sugar solution after three hours hunger. Bees were checked by feeding on non-treated sugar solution to observe PER response. Minimum proboscis extension was observed for acetamiprid and imidacloprid with 26% and 20% respectively at their recommend field doses while it was maximum for dinotefuran and thiamethoxam with 73% and 60% respectively. Only 40% bees showed response when exposed at 1/10 concentration of field dose for imidacloprid and the least at 1/100 of field dose. At control (Sugar solution) about 90% bees showed PER response. Among these neonicotinoid insecticides tested, imidacloprid and acetamiprid were the most damaging which impaired the olfactory learning performance in Apis mellifera.

• Journal of Environmental Health Sciences
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• v.50 no.3
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• pp.212-220
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• 2024

Background: 2-Ethylhexyl diphenyl phosphate (EHDPP) is widely used as a flame-retardant plasticizer in the production of polyvinyl chloride, adhesives, and food packaging. This chemical has been frequently detected in water, sediment, and indoor environments, and its lipophilicity raises concerns about bioaccumulation. Objectives: In this study, the effects of EHDPP on the development, behavioral changes, and growth hormone (GH) endocrine system of zebrafish larvae were investigated. Methods: Fertilized embryos were exposed to various concentrations (control, solvent control, 0.07, 0.7, 7, 70, and 700 ㎍/L) of EHDPP for 96 h. Developmental toxicity endpoints were observed daily. Behavioral changes under light-dark-light conditions and changes in hormones and genes related to GH/insulin-like growth factors (IGFs) axis were determined. Results: Significant decreases in survival, body length and moving distance were observed in zebrafish larvae exposed to 70 and 700 ㎍/L EHDPP. The concentrations of GH and IGF-1 were significantly decreased in zebrafish larvae exposed to 70 and 700 ㎍/L EHDPP. This change was well supported by changes in the transcription of genes involved in GH, IGF, IGF receptors, and IGF binding proteins. Conclusions: Our observations showed that exposure to 70 and 700 ㎍/L EHDPP could disrupt the feedback circuits of the GH/IGFs axis, ultimately leading to developmental toxicity, hypoactivity, and mortality.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.6
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• pp.2323-2326
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• 2015

It is urgently necessary to be aware of the distribution and risk areas of liver fluke, Opisthorchis viverrini, for proper allocation of prevention and control measures. This study aimed to investigate the human behavior, and environmental factors influencing the distribution in Surin Province of Thailand, and to build a model using stepwise multiple regression analysis with a geographic information system (GIS) on environment and climate data. The relationship between the human behavior, attitudes (<50%; $X_{111}$), environmental factors like population density ($148-169pop/km^2$; $X_{73}$), and land use as wetland ($X_{64}$), were correlated with the liver fluke disease distribution at 0.000, 0.034, and 0.006 levels, respectively. Multiple regression analysis, by equations OV= -0.599 + 0.005(population density ($148-169pop/km^2$); $X_{73}$) + 0.040 (human attitude (<50%); $X_{111}$) +0.022 (land used (wetland; X64), was used to predict the distribution of liver fluke. OV is the patients of liver fluke infection, R Square= 0.878, and, Adjust R Square= 0.849. By GIS analysis, we found Si Narong, Sangkha, Phanom Dong Rak, Mueang Surin, Non Narai, Samrong Thap, Chumphon Buri, and Rattanaburi to have the highest distributions in Surin province. In conclusion, the combination of GIS and statistical analysis can help simulate the spatial distribution and risk areas of liver fluke, and thus may be an important tool for future planning of prevention and control measures.