• Smart Structures and Systems
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• v.21 no.4
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• pp.479-491
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• 2018

Shape memory alloys (SMA) exhibit superelasticity which refers to the capability of entirely recovering large deformation upon removal of applied forces and dissipating input energy during the cyclic loading reversals when the environment is above the austenite finish temperature. This property is increasingly favored by the earthquake engineering community, which is currently developing resilient structures with prompt recovery and affordable repair cost after earthquakes. Compared with the other SMAs, NiTi SMAs are widely deemed as the most promising candidate in earthquake engineering. This paper contributes to evaluate the seismic performance of properly designed concentrically braced frames (CBFs) equipped with NiTi SMA braces under earthquake ground motions corresponding to frequently-occurred, design-basis and maximum-considered earthquakes. An ad hoc seismic design approach that was previously developed for structures with idealized SMAs was introduced to size the building members, by explicitly considering the strain hardening characteristics of NiTi SMA particularly. The design procedure was conducted to compliant with a suite of ground motions associated with the hazard level of design-basis earthquake. A total of four six-story CBFs were designed by setting different ductility demands for SMA braces while designating with a same interstory drift target for the structural systems. The analytical results show that all the designed frames successfully met the prescribed seismic performance objectives, including targeted maximum interstory drift, uniform deformation demand over building height, eliminated residual deformation, controlled floor acceleration, and slight damage in the main frame. In addition, this study indicates that the strain hardening behavior does not necessarily impose undesirable impact on the global seismic performance of CBFs with SMA braces.

• Proceedings of the KSCN Conference
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• 2005.10a
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• pp.20-32
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• 2005

With the prosperous economy, the status of diet and nutrition among the urban and rural Chinese population has been improved significantly. This paper will focuses on three main surveys in China. (1)'Food and Nutrition Surveillance System in China': Phase I focused on analysis of previous data. Phase II was a pilot survey initiated in Beijing, Hebei, Heilongjiang, Ningxia, Zhejiang, Guangzhou, and Sichuan in 1990. (2) 'The China Health and Nutrition Survey' is an ongoing longitudinal project covered 8(9) provinces in 1991,1993,1997,2000. This paper will analysis the adults aged 18 45 of 1991, 1993, 1997, and 2000. (3) Survey on the status of nutrition and health of the Chinese (2002) is an across sectional study covered 31 provinces, autonomous region and the municipalities. The data was used to analyze the status of food consumption and dietary nutrients intake of Chinese population. In the past ten years, the prevalence of malnutrition and nutrition deficiency has been continuously decreased. The consumptions of animal products, milk, and edible oil have been increased, while the dairy and legume products consumption decreased. The unbalance was showed with a downward trend in cereals, vegetables and fruits consumption and a significant increase in animal products and oil intake among urban people. Dietary pattern of some subjects went away to 'high energy density' diet. The deficiency of calcium, retinal and ascorbic acid etc, especially in the rural areas still exist. China is undergoing a remarkable, but undesirable, rapid transition towards a stage of the nutrition transition characterized by high rates of DR NCDs in a very short time. China is facing the dual challenges of nutrition deficiency and nutrition imbalance. The results can help to understand the dietary structure and the status of nutrition among Chinese people over the past years. It will provide the basis for formulating relevant state policies.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.220-225
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• 1984

In the grassland ecosystem dominated by Phragmites longivalvis in the delta of Nak Dong River, the production, decomposition, and accumulation of organic were estimated by the theoretical analysis. The amounts of organic carbon and organic matter of litter are $1020.43g/m^2\;and\;591.90g/m^2$, respectively. The amounts of organic matter and organic carbon on the grassland floor is $1154.96g/m^2\;and\;669.93g/m^2$, the ratio of annual litter production 'L' to the amount of accumulation on the top mineral soil (F, H and $A_2$ horizons) provided estimates of decay constant k. Constant k is 0.884 in the Phragmites longivalvis community. The vertical levels of organic matter and organic carbon is the highest in 120-140 cm of photosythetic system and in 0-20 cm of non-photosyntic system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.8
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• pp.1577-1584
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• 2002

This paper develops a finite element model for studying the occupant behavior and injury cofficients of a large-sized cab-over type truck. Since it does not have a room to absorb collision energy and deformation in front of the passenger compartment the deformation is directly transmitted to the passenger compartment. Moreover, since its steering column is attached on the frame, severe deformation of the frame directly affects on the steering wheel's movement. Therefore, if the occupant behavior and injury coefficients analysis is performed using a finite element model developed based on a sled test, it is very difficult to expect acquiring satisfactory results. Thus, the finite element model developing in this paper is based on the frontal crash test in order to overcome the inherent problems of the sled test based model commonly used in the passenger car. The occupant behavior and injury coefficients analysis is performed using PAM-CRASH installed in super-computer SP2. In order to validate the reliability of the developed finite element model, a frontal crash test is carried out according to a test method used fur developing truck occupant's secondary safety system in european community and japan. That is, test vehicle's collision direction is vertical to the rigid barrier and collision velocity is 45kph. Thus, measured vehicle pulses at the lower parts of the left and right B-pilla., dummy chest and head deceleration profiles, HIC(head injury criterial) and CA(chest acceleration) values, and dummy behavior from the frontal crash test are compared to the analysis results to validate reliability of the developed model.

• Journal of Environmental Science International
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• v.18 no.6
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• pp.691-698
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• 2009

Trickling filter has been extensively studied for the domestic wastewater treatment especially for the small scale plants in rural area. The performance of the trickling filter depends on the microbial community and their activity in the biofilms on the media. Nitrification. denitrification, and phosphorus removal of the trickling filter from the wastewater depend on the activity and the amount of the specific microorganisms responsible for the metabolism. For the estimation of the performance of a trickling filter, batch nitrification experiment and fluorescence in situ hybridization (FISH) were carried out to measure the microbial activity and its distribution on the media of the trickling filter. Batch nitrification activity measurement showed that the top part of the 1st stage trickling filter had the highest nitrification activity and the maximum activity was 0.002 g $NH_4$-N/g MLVSS${\cdot}$h. It is thought that higher substrate (ammonia) concentration yields more nitrifying bacteria in the biofilms. The dominant ammonia oxidizer and nitrite oxidizer in the biofilm were Nitrosomonas species and genus Nitrospira, respectively, by FISH analysis. Less denitrifiers were found than nitrifiers in the biofilm by the probe Rrp1088 which specifically binds to Rhodobacter, Rhodovulum, Roseobacter, and Paracoccus. Phosphorus accumulating bacteria were mostly found at the surface of the biofilm by probe Rc988 and PAO651 which specifically binds to Rhodocyclus group and their biomass was less than that of nitrifiers.

• Journal of Preventive Medicine and Public Health
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• v.39 no.5
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• pp.389-396
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• 2006

Objectives: A community-based, cross-sectional survey was conducted to determine theprevalence of osteoporosis and to evaluate the effects of body composition, health behaviors and reproductive history on bone density in postmenopausal women. Methods: The study subjects were 362 postmenopausal women, aged 45 years old or over, who were invited to the hospital. Information on their socio-demographic characteristics and the potential risk factors such as their past medical history, smoking, alcohol intake, exercise, diet and menstrual/reproductive histories were collected by trained interviewers. Weight, height, the body mass index ($kg/m^{2}$), and body composition variables were measured. Bone mineral density of the lumbar spine was measured by dual energy X-ray absorptiometry (DXA). Results: The prevalence of osteoporosis was 30.6% in the $45{\sim}64$ years old women, 52.5% in the elderly women aged $65{\sim}74$, and 68.7% in the women aged 75 years or over. After adjustment for the effect of potential covariates, those women in the highest 25% (4th quartile) of the lean body mass are less likely to have osteoporosis (aOR=0.31, 95% CI=0.12-0.76), compared with the lowest quartile group. More parity also had significantly detrimental effects on osteoporosis. Conclusions: These findings suggest that the prevalence of osteoporosis in postmenopausal women increased with age from 46.3% of those aged 45-64 to 68.7% for those aged 75 and over. Lean body mass and parity appeared significant contributor to bone mineral density in postmenopausal women in this population.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.493-498
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• 1986

In order to evaluate the effect of various cultural methods developed during last 30 years on grain yield of wheat and barley and structure of plant stand for uptake of nutrient and water, solar energy use and com-petitive capacity with weed, 10 kinds of cultural practices were compared in the clayey upland soil. Row fertilization is more effective for uptake of N,P and K than rotary fertilization. Weed occurrence was deeply related with width of non-seeded area in the row and affected yield decrease. Winter injury was more serious in the cultural practices with thick plant community than in those with isolated individual plant. Root distribution was more remarkable in drill seeding or broadcasting than row seeding and had positively correlated with water consumption of barley.

• Journal of Microbiology and Biotechnology
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• v.26 no.5
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• pp.867-875
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• 2016

Archaea substantially contribute to global geochemical cycling and energy cycling and are impacted by land-use change. However, the response of archaeal communities to a change from upland field to paddy field has been poorly characterized. Here, soil samples were collected at two depths (0-20 cm and 20-40 cm) from one upland field and six paddy fields that were established on former upland fields at different times (1, 5, 10, 20, 30, and 40 years before the study). Barcoded pyrosequencing was employed to assess the archaeal communities from the samples at taxonomic resolutions from phylum to genus levels. The total archaeal operational taxonomic unit (OTU) richness showed a significant positive correlation with the land-use change duration. Two phyla, Euryarchaeota and Crenarchaeota, were recorded throughout the study. Both the relative abundance and OTU richness of Euryarchaeota increased at both depths but increased more steadily at the subsurface rather than at the surface. However, these data of Crenarchaeota were the opposite. Additionally, the archaeal composition exhibited a significant relationship with C/N ratios, total phosphorus, soil pH, Olsen phosphorus, and the land-use change duration at several taxonomic resolutions. Our results emphasize that after a change from upland fields to paddy fields, the archaeal diversity and composition changed, and the duration is an important factor in addition to the soil chemical properties.

• Journal of Distribution Science
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• v.4 no.1
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• pp.161-173
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• 2006

The most important two decision-makings which a retail store owner face require which place of the store should geographically be established and which stock should be properly placed on the shelves. The problem of geographic positioning is the decision-making for the store's positioning and stock arrangement within the retail store is the decision-making for the placement store. In order to determine the positioning, the expected area should be analyzed so that the analysis of commercial area can usually be implemented in accordance with retail marketing strategy and therefore the sized of the potential market for example each distric's clientele, competition and, a municipal community's regulations, could be evaluated. But I contend that with only the size of potential market does not give an adequate answer to the problem of a store's positioning. Through the estimation of commercial are in combination with feng-shui, the theory of divination based on topography, the store's position could be selected, taking a positive energy, Gi. This thesis is the starting point of these trials. In the long run, the actual analysis of the study should be continued in a more scientific, systematic, statistical way.

• Journal of Korea Technology Innovation Society
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• v.18 no.1
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• pp.126-150
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• 2015

Korea's experiences in the use and development of nuclear energy are recognized as a successful model as a developing country in the international nuclear community. With these experiences, Korea is able to contribute to the progress of Korean nuclear industry and international society as a nuclear advanced country. This paper reviews and analyzes the current situation and major issues in securing the international legal status of RCA Regional Office hosted by Korean Government since 2002. In this connection, major political environments and relevant issues in facilitating the revision of RCA Agreement and securing legal status of the RCARO are also investigated. It is essential to amend the 1987 RCA Agreement or to conclude the its supplementary agreement for the securing of the international legal status of RCA Regional Office at the RCA policy meeting prior to extension of the agreement in 2017 and after. It is recommended for the Korean Government to establish and operate the inter-ministry governmental task force teams to facilitate and support the required actions in the national and diplomatic actions in the regional level for the sustainable development of the RCA and RCA Regional Office.