• Journal of the Korean Association of Geographic Information Studies
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• v.12 no.2
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• pp.120-131
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• 2009

This study measured the centripetal force and effective scope of the population spread from urban center and subcenters in order to diagnose the urban spatial structure of the formation of a multicentric city structure in Busan. The study analyzed the variability of the determination coefficient value (R square) with a negative exponential function derived from the population density model by extending the circular region into 5-km units. The aim of this study was to measure changes in the effective scope of the population centripetal force of the urban center and subcenter in 5-year intervals from 1995 to 2005 using census data. The explanatory adequacy of the population density function was examined with the bias of the function to calculate the distance error between the real location of the urban center and the optimal location, according to the population density function. To summarize the results, the value for the area of Jungangdong showed a continuous reduction, whereas Seomyeon (Bujeondong) maintained explanatory adequacy without a large change. As a whole, Busan was in the process of continuous diversification, in spite of its reduced population. Therefore, it appears necessary to strengthen the function of the urban center and subcenter and to supply adequate dwelling zones close to downtown to form a more efficient urban spatial structure. The results of the present study will be utilized as basic data for the formulation of a political approach to the efficient reorganization of spatial structure by correlating concrete spatial information with the population variability of Busan's urban center and subcenter.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.27 no.4
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• pp.340-360
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• 1982

Because of the continuing rapid increase in pesticide usage in Taiwan, much attention has been focus on pesticide contamination of food and effect of pesticides on human and environmental health. The Plant Protection Center (PPC) conducts safety evaluation of pesticides usee! in Taiwan. The pesticides are classified into different groups based on their acute toxicities. Pesticides which are classified into extremely toxic group are not allow to used on short term crops or the continuously harvest crops. The acute toxicity of pesticides to the beneficial insects are also studied, special attention has been paid to the two predators of rice brown planthopper. 60% of cultivated land in Taiwan are paddy field; therefore, acute fish toxicity was taken into consideration when a pesticide was applied for registration to be used in the paddy. Fish toxicities were evaluated by the dangerous rating value which is the amount of pesticide residue in the field water over the TLM value. Mutagenicity of pesticides was continuously evaluated by using Arne's microbial testing method. Island wide survey of residual levels of pesticides of known pollutants such as chlorinated hydrocarbon . insecticides, mercurial compounds in soil, water and biological samples were carried out constantly. The potential of a new1y Imported esticides to pollute the environment were studied by using model ecosystem. Ecological magnification (EM) of a chemical was calculated from model ecosystem. A chemical was considered as a pollutant when its EM value over 5000. In order to ensure the levels of pesticides residue of the crop within the safety limit. The 'tolerance' of pesticides on different crop groupings were established base on 1) acceptable daily intake value of individual pesticides, 2) average daily consumption of each crop groupings by Chinese person, 3) Actual residues of pesticides. on different crops obtained from supervised trials. Total about 79 pesticides for which the tolerances have been established on different crop groupings. Because the intensive agricultural system was adopted in Taiwan. The phytotoxicity of pesticides to the non-target crops was therefore become one of the important factor in the safety evaluation of pesticide usage. These will include 1) direct injury, 2) injury caused by pesticide polluted irrigation water, 3) injury caused by the pesticide polluted soil, 4) reduction of growth caused by the effect of pesticide on the soil microorganisms. This paper will reviewed all the aspects mentioned in the previous .paragraphs. Most the works have done in Taiwan by the PPC.y the PPC.

• Women's Health Nursing
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• v.5 no.1
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• pp.133-145
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• 1999

The purposesof the study are to analyze the community nursing center in U.S.A and to develop the model of nursing care system based on nurse-midwifery clinic in community for women's health in Korea. 1. In America nursing center is defined as nurse-anchored system of primary care delivery or neighborhood health center. Nursing centers are identified the following four types: (1) community outreach centers, which are similar to traditional public health clinics: (2) institutional-based centers following the mission of a large institution, such as a hospital or university: (3) wellness/health promotion centers, which offer screening, education, counseling, triage, and health maintenance services: and (4) independent practice. Nursing centers are a concept of services provided by nurses in practice arrangements in a community. Nursing centers offer a variety of services, ranging from primary care provided by advanced practice nurses with medical acute management and nursing care to the more traditional education, health promotion, screening wellness and coordination services. Some services, such as the care provided by advanced practice nurses are reimbursed under various insurance plan in some instances and states, where as others, such as preventive and educational services, are not. Thus, lack of reimbursement has threatened the survival of some centers. Licensing of nursing centers varies by state and program and accreditation of nursing centers is also limited. 52% of centers are affiliated with another facility and 48% are freestanding centers. The number of registered nurse at the nursing centers ranges from just one to 115, with a mean of eight RNs peragency and a median of three. Nursing centers avail ability varies: 14% are open 24 hours, 27% have variable short hours, 23% are open 6-7 days per week, and 36% are open Monday- Friday. As the result of my visiting three health centers in Seattle and San Francisco, the women's primary care nurse practitioners focus on a systematic and comprehensive assessment of the health status of women and diagnosis and management of common physical and psychosocial health concerns of women in ambulatory settings. Therapeutic nursing strategies are directed toward self-care, risk reoduction, health surveillance, stress reduction, healthy nutrition, social support, healthy coping, psychological well-being, and pharmacological therapy. They function as primary care providers for the well ness and illness care of women from adolescence through the older adult years and pregnant families. 2. In Korea a nurse-midwife practices independently for pregnant women's health including childbearing family at her own clinic in community. Her services are reimbursed under national health insurance but they are not paid on a fee-for-service schedule covering items. Analyzing the nursing centers in America, I suggest that nurse-midwifery clinics offer primary care for women and home care for chronic ill patients. The health law and health insurance policy should be reovised in order to expand nurse-midwife's and home care nurse's roles at nurse-midwifery clinic.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6673-6680
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• 2013

Objective: Insulin resistance (IR) is an established risk factor for colorectal cancer (CRC). Given that CRC and IR physiologically overlap and the calpain-10 gene (CAPN10) is a candidate for IR, we explored the association between CAPN10 and CRC risk. Methods: Blood samples of 400 case-control pairs were genotyped, and the lifestyle and dietary habits of these pairs were recorded and collected. Unconditional logistic regression (LR) was used to assess the effects of CAPN10 SNP43 and SNP19, and environmental factors. Both generalized multifactor dimensionality reduction (GMDR) and the classification and regression tree (CART) were used to test gene-environment interactions for CRC risk. Results: The GA+AA genotype of SNP43 and the Del/Ins+Ins/Ins genotype of SNP19 were marginally related to CRC risk (GA+AA: OR = 1.35, 95% CI = 0.92-1.99; Del/Ins+Ins/Ins: OR = 1.31, 95% CI = 0.84-2.04). Notably, a high-order interaction was consistently identified by GMDR and CART analyses. In GMDR, the four-factor interaction model of SNP43, SNP19, red meat consumption, and smoked meat consumption was the best model, with a maximum cross-validation consistency of 10/10 and testing balance accuracy of 0.61 (P < 0.01). In LR, subjects with high red and smoked meat consumption and two risk genotypes had a 6.17-fold CRC risk (95% CI = 2.44-15.6) relative to that of subjects with low red and smoked meat consumption and null risk genotypes. In CART, individuals with high smoked and red meat consumption, SNP19 Del/Ins+Ins/Ins, and SNP43 GA+AA had higher CRC risk (OR = 4.56, 95%CI = 1.94-10.75) than those with low smoked and red meat consumption. Conclusions: Though the single loci of CAPN10 SNP43 and SNP19 are not enough to significantly increase the CRC susceptibility, the combination of SNP43, SNP19, red meat consumption, and smoked meat consumption is associated with elevated risk.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.67-74
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• 2020

Middle-aged women experience physical and mental changes along with the loss of femininity, and they feel psychologically empty according as their child's growth and independence reduces the role of care and parenting. These women understand the sense of loss and emptiness caused of their role reduction as an opportunity to maintain their values and beliefs for their leisure life. Accordingly, middle-aged women overcome negative emotions facing in the middle-aged such as depression or empty mind, and establish self-esteem and social support in recognizing it as an opportunity for building relationship and self-realization in social relations, which come through human to human communication by doing craft activities. In this study, in order to analyze the effect of the experience factor of craft activity to self-esteem and social support for middle-aged women, we set up a research model with the experience factor of craft activity as an independent variable and self-esteem and social support as dependent variables. As a result of the study, educational experiences, recreational experiences, and deviant experiences had a meaningful effect on self-esteem, but aesthetic experiences did not have meaningful effect. And, recreational experiences and aesthetic experiences had a meaningful effect on social support, but educational experiences and deviant experiences did not have meaningful effect on social support. Therefore, the institutional system for craft experiences, that can provide content of environmental characteristics for aesthetic factor and visual elements are required. It influences to the change of senses and emotions of middle-aged women. Also, there are limitations that this study did not consider factors of ultimate life changes through craft activities. Thus this study suggests development of new model for variables of wellbeing-related matters.

• Korean Chemical Engineering Research
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• v.53 no.2
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• pp.150-155
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• 2015

Recently, LNG receiving terminals have been widely constructed and expanded for an increase in LNG demand. Selection of the storage tank for send-out and estimation of send-out flow rate have significant influence to process operation and economics. In this study, a send-out flow rate of each storage tank is optimized in order to minimize the total BOG generation rate. Considering a size and characteristic of each storage tanks, BOG flow rates are estimated using a dynamic simulation with varying liquid levels in the tanks. The regression model is developed fitting BOG flow rates and tank liquid levels, which are boil off rate model to predict BOG flow rates with particular level data. The objective function and constraints including required total send-out flow rate and level limit in the tanks are formulated to optimize a send-out flow rate of each tank. This method for optimization of send-out operation is applied to the Incheon LNG receiving terminal considering two scenarios for various liquid levels and maximum and minimum required send-out flow rates. For maximum required send-out flow rate, this method achieves BOG reduction of 9% comparing with assumed conventional operation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.2
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• pp.88-96
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• 1983

The effect of lowering water activity of various humectants has been reported in the previous papers. In this study, that effect of humectants used in combination with each other was discussed. Additionally, the Aw measurements were also compared to the predicted values of Aw derived from the equation of Raoult's law and the linear slope method by Sloan and Labuza. Each mixed humectant was thought to be salted-out by the other, and thus Aw values were observed to be somewhat lower as the result in all model preparations. The effect of lowering water activity by NaCl was the highest, and the efficiency of reduction of Aw was decreased in the order of NaCl, sodium lactate, glycerin, propylene glycol and sorbitol when each of them was combinated with other humectants. Aw values calculated by the equation of Raoult's law were not agreed so well to the measured Aw, so it was likely not to be the useful method for predicting Aw values in mixed humectants to far as they have showed higher ability for lowering Aw in the previous papers. The equations of prediction were derived from Aw values to be measured actually in the model Kamaboko.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.11-18
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• 2014

Most of the energy efficient MAC protocols for wireless sensor networks (WSNs) are based on duty cycling in a single channel and show competitive performances in a small number of traffic flows; however, under concurrent multiple flows, they result in significant performance degradation due to contention and collision. We propose a multi-channel pipelining (MCP) method for convergecast WSN in order to address these problems. In MCP, a staggered dynamic phase shift (SDPS) algorithms devised to minimize end-to-end latency by dynamically staggering wake-up schedule of nodes on a multi-hop path. Also, a phase-locking identification (PLI) algorithm is proposed to optimize energy efficiency. Based on these algorithms, multiple flows can be dynamically pipelined in one of multiple channels and successively handled by sink switched to each channel. We present an analytical model to compute the duty cycle and the latency of MCP and validate the model by simulation. Simulation evaluation shows that our proposal is superior to existing protocols: X-MAC and DPS-MAC in terms of duty cycle, end-to-end latency, delivery ratio, and aggregate throughput.

• The Korea Journal of Herbology
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• v.36 no.5
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• pp.81-91
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• 2021

Objectives : Osteoporosis is a systemic skeletal disease that decreases bone density and increases the risk of fractures. Bisphosphonates and SERMs are mainly used to treat osteoporosis, but, long-term use increases the risk of side effects such as jaw bone necrosis and breast cancer. Therefore, it is necessary to develop a therapeutic agent for a natural product with few side effects. Water extract of Lonicerae Japonicae Flos (wLF) was mainly found to have anti-cancer and anti-inflammatory effects. However, the effect of wLF on osteoporosis has not been elucidated. Therefore, this experiment investigated the effect of wLF on osteoclasts, osteoblasts and osteoporosis models. Methods : In order to study the effect of wLF on osteoporosis, the OVX-induced rat model was used for in vivo study. After 8 weeks, we measured body weight, uterine weight, liver weight, femur weight, bone density, trabecular area and tibia ash weight. To determine the effect of wLF on osteoclast differentiation, we measured the number of TRAP-positive cells and TRAP activity. To examine the effect of wLF on the expression of osteoblast-related genes, we measured the mRNA expression of alkaline phosphatase (ALP, Alpl) and osteocalcin (OCN, Bglap2). Results : In vivo experiment, wLF inhibited the reduction of femur weight, trabecular area, bone density and tibia ash weight. In vitro experiment, wLF had no significant effect on osteoclast differentiation. However, wLF increased the mRNA expression of Alpl and Bglap2 in MC3T3-E1 cell. Conclusions : This result suggested that wLF may be used for the treatment and prevention of postmenopausal osteoporosis.

• Asia Marketing Journal
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• v.16 no.1
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• pp.35-69
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• 2014

The impact of competition on pricing has been studied in the context of counterfactual merger analyses where expected optimal prices in a hypothetical monopoly are compared with observed prices in an oligopolistic market. Such analyses would typically assume static decision making by consumers and firms and thus have been applied mostly to data obtained from consumer packed goods such as cereal and soft drinks. However such static modeling approach is not suitable when decision makers are forward looking. When it comes to the markets for durable products with indirect network effects, consumer purchase decisions and firm pricing decisions are inherently dynamic as they take into account future states when making purchase and pricing decisions. Researchers need to take into account the dynamic aspects of decision making both in the consumer side and in the supplier side for such markets. Firms in a two-sided market typically subsidize one side of the market to exploit the indirect network effect. Such pricing behaviors would be more prevalent in competitive markets where firms would try to win over the battle for standard. While such qualitative expectation on the relationship between pricing behaviors and competitive structures could be easily formed, little empirical studies have measured the extent to which the distinct pricing structure in two-sided markets depends on the competitive structure of the market. This paper develops an empirical model to measure the impact of competition on optimal pricing of durable products under indirect network effects. In order to measure the impact of exogenously determined competition among firms on pricing, we compare the equilibrium prices in the observed oligopoly market to those in a hypothetical monopoly market. In computing the equilibrium prices, we account for the forward looking behaviors of consumers and supplier. We first estimate a demand function that accounts for consumers' forward-looking behaviors and indirect network effects. And then, for the supply side, the pricing equation is obtained as an outcome of the Markov Perfect Nash Equilibrium in pricing. In doing so, we utilize numerical dynamic programming techniques. We apply our model to a data set obtained from the U.S. video game console market. The video game console market is considered a prototypical case of two-sided markets in which the platform typically subsidizes one side of market to expand the installed base anticipating larger revenues in the other side of market resulting from the expanded installed base. The data consist of monthly observations of price, hardware unit sales and the number of compatible software titles for Sony PlayStation and Nintendo 64 from September 1996 to August 2002. Sony PlayStation was released to the market a year before Nintendo 64 was launched. We compute the expected equilibrium price path for Nintendo 64 and Playstation for both oligopoly and for monopoly. Our analysis reveals that the price level differs significantly between two competition structures. The merged monopoly is expected to set prices higher by 14.8% for Sony PlayStation and 21.8% for Nintendo 64 on average than the independent firms in an oligopoly would do. And such removal of competition would result in a reduction in consumer value by 43.1%. Higher prices are expected for the hypothetical monopoly because the merged firm does not need to engage in the battle for industry standard. This result is attributed to the distinct property of a two-sided market that competing firms tend to set low prices particularly at the initial period to attract consumers at the introductory stage and to reinforce their own networks and eventually finally to dominate the market.