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A study on the improvement of distribution system by overseas agricultural investment (해외농업투자에 따른 유통체계 개선방안에 관한 연구)

  • Sun, Il-Suck;Lee, Dong-Ok
    • Journal of Distribution Science
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    • v.8 no.3
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    • pp.17-26
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    • 2010
  • Recently concerns have been raised due to the unbalanced supply of crops: the price of crops has been unstable and at one point the price went up so high that the word Agflation(agriculture+ inflation) was coined. Korea, in particular, is a small-sized country and needs to secure the stable supply of crops by investing in the produce importation at a national level. Investment in foreign produce importation is becoming more important as a measure for sufficient supply of crops, limited supply of domestic crops, weakened farming conditions worldwide, as well as recent changes in the use of crops due to the development of bio-fuels, influence of carbon emission on crops, the price increase in crops, and influx of foreign hot money. However, there are many problems with investing in foreign produce importation: lack of support from the government; lack of farming information and technology; difficulty in securing the capital; no immediate pay-off from the investment and insufficient management. Although foreign produce is originally more price-competitive than domestic produce, it loses its competiveness in the process of importation (due to high tariffs) and poor distribution system, which makes it difficult to sell in Korea. Therefore, investment in foreign produce importation is being questioned for feasibility; to make it possible, foreign produce must maintain the price-competitiveness. Especially, harvest of agricultural products depends on natural and geographical conditions of each country and those products have indigenous properties, so distribution system according to import and export of agricultural products should be treated more carefully than that of other industries. Distribution costs are differentiated into each item and include cost of sorting and wrapping, cost of wrapping materials, cost of domestic transport, cost of international transport and cost of clearing customs for import and export. So transporting and storing agricultural products generates considerable costs compared with other products. Also, due to upgrade of dietary life, needs for stability, taste and visible quality toward food including agricultural products are being raised and wrong way of storage causes decomposition of food and loss of freshness, making the storage more difficult than that in room temperature, so storage and transport in distribution of agricultural products needs specialty. In addition, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. However, existing distribution system of agricultural products is exposed to various problems including problems in distribution channel, making distribution and strategy for distribution and those problems are as follows. First, in case of investment in overseas agricultural industry, stable supply of the products is difficult because areas of production are dispersed widely and influenced by outer factors due to including overseas distribution channels. Also, at the aspect of quality, standardization of products is difficult, distribution system is quite complicated and unreasonable due to long distribution channels according to international trade and financial and institutional support is not enough. Especially, there are quite a lot of ineffective factors including multi level distribution process, dramatic gap between production cost and customer's cost, lack of physical distribution facilities and difficulties in storage and transport due to lack of wrapping containers. Besides, because import and export of agricultural products has been manages under the company's own distribution according to transaction contract between manufacturers and exporting company, efficiency is low due to excessive investment in fixed costs and lack of specialty in dealing with agricultural products causes fall of value of products, showing the limit to lose price-competitiveness. Especially, because lack of specialty in distribution and circulation such as storage and wrapping does not solve limit factors in distance, the distribution and circulation has been limited to a form of import and export within short-distant region. Therefore, need for distribution out-sourcing which can satisfy specialty in managing distribution and circulation and it is needed to establish more effective distribution system. Second, among tangible and intangible services which promote the efficiency of the whole distribution, a function building distribution environment which includes distribution information, system for standard and inspection, distribution finance, system for diversification of risks, education and training, distribution administration and tax system is wanted. In general, such a function building distribution environment is difficult to be changed and supplement innovatively because its effect compared with investment does not appear immediately despite of its necessity. Especially, in case of distribution of agricultural products, as a function of collecting and distributing is performed individually through various channels, the importance of distribution information and standardization is getting more focus due to the problem of repetition of work and lack of specialty. Also, efficient management of distribution is quite difficult due to lack of professionals in distribution, so support to professional education is needed. Third, though effort to keep self-sufficiency ratio of staple food, rice is regarded as important at the government level, level of dependency on overseas of others crops is high. Therefore, plan for stable securing food resources aside from staple food is also necessary. Especially, governmental organizations of agricultural products distribution in Korea are production-centered and have unreasonable structure whose function at the aspect of distribution and consumption is quite insufficient. And development of new distribution channels which can deal with changes in distribution environment and they do not achieve actual results of strategy for distribution due to non-positive strategy for price distribution. That is, it implies the possibility that base for supply will become vulnerable because it does not mediate appropriate interests on total distribution channels such as manufacturers, wholesale dealers and vendors by emphasizing consumer protection excessively in the distribution of agricultural products. Therefore, this study examined fundamental concept and actual situation for our investment to overseas agriculture, drew necessities, considerations, problems, etc. of overseas agricultural investment and suggested improvements at the level of distribution for price competitiveness of agricultural products cultivated in overseas under five aspects; government's indirect support, distribution's modernization and distribution information function's strengthening, government's political support for distribution facility, transportation route, load and unloading works' improvement, price competitiveness' securing, professional manpower's cultivation by education and training, etc. Here are some suggestions for foreign produce importation. First, the government should conduct a survey on the current distribution channels and analyze the situation to establish a measure for long-term development plans. By providing each agricultural area with a guideline for planning appropriate production of crops, the government can help farmers be ready for importation, and prevent them from producing same crops all at the same time. Government can sign an MOU with the foreign government and promote the importation so that the development of agricultural resources can be stable and steady. Second, the government can establish a strategy for an effective distribution system by providing farmers and agriculture-related workers with the distribution information such as price, production, demand, market structure and location, feature of each crop, and etc. In order for such distribution system to become feasible, the government needs to reconstruct the current distribution system, designate a public organization for providing distribution information and set the criteria for level of produce quality, trade units, and package units. Third, the government should provide financial support and a policy to seek an efficient distribution channel for foreign produce to be delivered fresh: the government should expand distribution facilities (for selecting, packaging, storing, and processing) and transportation vehicles while modernizing old facilities. There should be another policy to improve the efficiency of unloading, and to lower the cost of distribution. Fourth, it is necessary to enact a new law covering exceptional cases for importing produce in order to maintain the price competitiveness; currently the high tariffs is keeping the imported produce from being distributed domestically. However, the new adjustment should be made carefully within the WTO regulations since it can create a problem from giving preferential tariffs. The government can also simplify the distribution channels in order to reduce the cost in the distribution process. Fifth, the government should educate distributors to raise the efficiency and to modernize the distribution system. It is necessary to develop human resources by educating people regarding the foreign agricultural environment, the produce quality, management skills, and by introducing some successful cases in advanced countries.

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Response of Rice Yield to Nitrogen Application Rate under Variable Soil Conditions

  • Ahn Nguyen Tuan;Shin Jin Chul;Lee Byun-Woo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.50 no.4
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    • pp.247-255
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    • 2005
  • ice yield and plant growth response to nitrogen (N) fertilizer may vary within a field, probably due to spatially variable soil conditions. An experiment designed for studying the response of rice yield to different rates of N in combination with variable soil conditions was carried out at a field where spatial variation in soil properties, plant growth, and yield across the field was documented from our previous studies for two years. The field with area of 6,600 m2 was divided into six strips running east-west so that variable soil conditions could be included in each strip. Each strip was subjected to different N application level (six levels from 0 to 165kg/ha), and schematically divided into 12 grids $(10m \times10m\;for\;each\;grid)$ for sampling and measurement of plant growth and rice grain yield. Most of plant growth parameters and rice yield showed high variations even at the same N fertilizer level due to the spatially variable soil condition. However, the maximum plant growth and yield response to N fertilizer rate that was analyzed using boundary line analysis followed the Mitcherlich equation (negative exponential function), approaching a maximum value with increasing N fertilizer rate. Assuming the obtainable maximum rice yield is constrained by a limiting soil property, the following model to predict rice grain yield was obtained: $Y=10765{1-0.4704^*EXP(-0.0117^*FN)}^*MIN(I-{clay},\;I_{om},\;I_{cec},\;I_{TN},\; I_{Si})$ where FN is N fertilizer rate (kg/ha), I is index for subscripted soil properties, and MIN is an operator for selecting the minimum value. The observed and predicted yield was well fitted to 1:1 line (Y=X) with determination coefficient of 0.564. As this result was obtained in a very limited condition and did not explain the yield variability so high, this result may not be applied to practical N management. However, this approach has potential for quantifying the grain yield response to N fertilizer rate under variable soil conditions and formulating the site-specific N prescription for the management of spatial yield variability in a field if sufficient data set is acquired for boundary line analysis.

A Preliminary Study on Development and Evaluation of Home Health Care Nurse Clinical Practice Program -Focused on Postoperative Orthopedic Patients- (가정간호사 임상실무 훈련프로그램 개발과 평가를 위한 사전 연구 -정형외과 수술 환자를 중심으로-)

  • 서영숙
    • Journal of Korean Academy of Nursing
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    • v.26 no.1
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    • pp.15-32
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    • 1996
  • The clinical practice program for home care nurses was implemented in June 1994, to help to set up a hospital-based home care system in the Kwangju City area as a collaborative work between the Department of Orthopedic Surgery at Chunnam University Hospital and Chunnam University School of Nursing. Under the developed clinical practice strategy, the eight week training was given to five licensed home care nurses who had completed Part I and II of the home health care nursing practicum from June 1994. The purpose of this descriptive evaluation study was to identify the effectiveness of the clinical practice program for home care nurses specialized in the area of patient care for people with musculoskeletal function impairment. As a method in data analysis, data triangulation was used in the five home care nurse case evaluations. The variety of data analyzed include confidence score by home care nurse self-evaluation, patient and family member satisfaction scores, and competency score by preceptor evaluation. The study findings revealed that an increase rate in nursing performance didrate necessarily coincide with an increase not in competency score and also, not with the patient /family member satisfaction scores. And an order derived from the clinical performance scores of five home care nurses corresponded to those from three measurements-competency score, patient satisfaction score, and family member satisfaction score. However, it differed from the order associated with the confidence score. Consistency derived from the three objective evaluation methods may lead to the possibility that the level of competency measured by educator can be further explained by the levels of patient/family member satisfaction. The salient finding of this study was that, in case of nurse A who have had little clinical experience in the orthopedic patient care, there was a significant increase in the level of confidence and competency in subscale of professional skill with the home care clinical practice. Therefore, the effect of the clinical practice program would be successful for nurses who have had little experience in the area of specialization. The study results suggest that there might be some time difference in the development of cognitive sense (confidence) in performance and actual clinical performance (competency). In future research, relationships between the confidence and competency score, and between the confidence score and the patient satisfaction score should to be measured in different time frame to achieve a better explanation power of the study outcome.

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A Study on the Development of the Seismic Fragility Functions of the High Speed Railway Tunnels in use (기존 고속철도 터널의 지진취약도 함수 개발에 관한 연구)

  • Kim, Hongkyoon;Shin, Chulsik;Lee, Taehyung;Lee, Jonggun;Park, Duhee
    • Journal of the Korean GEO-environmental Society
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    • v.15 no.11
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    • pp.67-75
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    • 2014
  • In this study, the staged seismic performance evaluations were conducted to the 91 high speed railway tunnels in use for checking whether to comply with the recent design criteria or not. In addition, the seismic fragility functions of the tunnels were developed to allow the probabilistic risk assessment. The results of the staged seismic performance evaluations which consist of a preliminary assessment and a detailed assessment, show that the tunnels comply with the recent design criteria. With reference to the results of previous studies, a form of the proposed seismic fragility functions was set as a log-normal distribution by PGA, and the parameters of the functions were determined by using the probability of damage for the design PGA level. The seismic fragility functions were developed for each types (Cut & Cover, NATM) of tunnels. The seismic fragility functions from this study and the existing research results (FEMA, 2004) were compared to evaluate the seismic performance level of the tunnels, as a result the tunnels of this study were relatively superior to the ASSM tunnels on the seismic performance.

The Extreme Value Analysis of Deepwater Design Wave Height and Wind Velocity off the Southwest Coast (남서 해역 심해 설계 파고 및 풍속의 극치분석)

  • Kim, Kamg-Min;Lee, Joong-Woo;Lee, Hun;Yang, Sang-Yong;Jeong, Young-Hwan
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.245-251
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    • 2005
  • When we design coastal and harbol facilities deepwater design wave and wind speed are the important design parameters. Especially, the analysis of these informations is a vital step for the point of disaster prevention. In this study, we made and an extreme value analysis using a series of deep water significant wave data arranged in the 16 direction and supplied by KORDI real-time wave information system ,and the wind data gained from Wan-Do whether Station 1978-2003. The probability distributions considered in this characteristic analysis were the Weibull, the Gumbel, the Log-Pearson Type III, the Normal, the Lognormal, and the Gamma distribution. The parameter for each distribution was estimated by three methods, i.e. the method of moments, the maximum likelihood, and the method of probability weight moments. Furthermore, probability distributions for the extreme data had been selected by using Chi-square and Kolmogorov-Smirnov test within significant level of 5%, i,e. 95% reliance level. From this study we found that Gumbel distribution is the most proper model for the deep water design wave height off the southwest coast of Korea. However the result shows that the proper distribution made for the selected site is varied in each extreme data set.

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The Effect of Mineral Trioxide Aggregate on the Production of Growth Factors and Cytokine by Human Periodontal Ligament Fibroblasts (Mineral trioxide aggregate (MTA)가 치주인대 섬유아세포에서 분비되는 cytokine과 성장인자 TGF-β1, FGF-2 발현에 미치는 영향)

  • Kwon, Ji-Yoon;Lim, Sung-Sam;Baek, Seung-Ho;Bae, Kwang-Shik;Kang, Myung-Hoe;Lee, Woo-Cheol
    • Restorative Dentistry and Endodontics
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    • v.32 no.3
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    • pp.191-197
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    • 2007
  • Mineral trioxide aggregate (MTA) would influence healing of periapical tissues by modulating the production of growth factors and cytokines from PDL fibroblasts, however, the studies are insufficient. Therefore, the purpose of this study was to monitor the expression of transforming growth factor-beta1 $(TGF-\beta1)$, fibroblast growth factor-2 (FGF-2), and interleukin-6 (IL-6) from PDL fibroblasts in the presence of MTA. The human PDL fibroblasts were seeded onto the set MTA or IRM at a level of $1\times10^5$ cells per unit well, and further incubated for 6, 12, 24, and 48 hours. The levels of $TGF-\beta1$, FGF-2 and IL-6 from the supernatant were measured by enzyme-linked immunosorbent assay (ELISA) The data were analyzed using one-way ANOVA. The level of $TGF-\beta1$ was down-reg ulated when the cells were grown in the presence of MTA except at 6 hours. The levels of FGF-2 release were significantly suppressed when PDL fibroblasts were grown in the presence of MTA or IRM at all time intervals (p < 0.05). The expressions of IL-6 from MTA treated co)Is were comparable to those of untreated control cells throughout the observation periods. We presume that this material inhibits the stimulatory function of growth factors on granulation tissue formation and in turn, it promotes the healing process modulated by other bone-remodeling cells.

Molecular Analysis of Growth Factor and Clock Gene Expression in the Livers of Rats with Streptozotocin-Induced Diabetes

  • Kim, Joo-Heon;Shim, Cheol-Soo;Won, Jin-Young;Park, Young-Ji;Park, Soo-Kyoung;Kang, Jae-Seon;Hong, Yong-Geun
    • Reproductive and Developmental Biology
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    • v.33 no.3
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    • pp.163-169
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    • 2009
  • Many biological systems are regulated by an intricate set of feedback loops that oscillate with a circadian rhythm of roughly 24 h. This circadian clock mediates an increase in body temperature, heart rate, blood pressure, and cortisol secretion early in the day. Recent studies have shown changes in the amplitude of the circadian clock in the hearts and livers of streptozotocin (STZ)-treated rats. It is therefore important to examine the relationships between circadian clock genes and growth factors and their effects on diabetic phenomena in animal models as well as in human patients. In this study, we sought to determine whether diurnal variation in organ development and the regulation of metabolism, including growth and development during the juvenile period in rats, exists as a mechanism for anticipating and responding to the environment. Also, we examined the relationship between changes in growth factor expression in the liver and clock-controlled protein synthesis and turnover, which are important in cellular growth. Specifically, we assessed the expression patterns of several clock genes, including Per1, Per2, Clock, Bmal1, Cry1 and Cry2 and growth factors such as insulin-like growth factor (IGF)-1 and -2 and transforming growth factor (TGF)-${\beta}1$ in rats with STZ-induced diabetes. Growth factor and clock gene expression in the liver at 1 week post-induction was clearly increased compared to the level in control rats. In contrast, the expression patterns of the genes were similar to those observed after 5 weeks in the STZ-treated rats. The increase in gene expression is likely a compensatory change in response to the obstruction of insulin function during the initial phase of induction. However, as the period of induction was extended, the expression of the compensatory genes decreased to the control level. This is likely the result of decreased insulin secretion due to the destruction of beta cells in the pancreas by STZ.

Cyberknife Dosimetric Planning Using a Dose-Limiting Shell Method for Brain Metastases

  • Yoon, Kyoung Jun;Cho, Byungchul;Kwak, Jung Won;Lee, Doheui;Kwon, Do Hoon;Ahn, Seung Do;Lee, Sang-Wook;Kim, Chang Jin;Roh, Sung Woo;Cho, Young Hyun
    • Journal of Korean Neurosurgical Society
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    • v.61 no.6
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    • pp.753-760
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    • 2018
  • Objective : We investigated the effect of optimization in dose-limiting shell method on the dosimetric quality of CyberKnife (CK) plans in treating brain metastases (BMs). Methods : We selected 19 BMs previously treated using CK between 2014 and 2015. The original CK plans ($CK_{original}$) had been produced using 1 to 3 dose-limiting shells : one at the prescription isodose level (PIDL) for dose conformity and the others at low-isodose levels (10-30% of prescription dose) for dose spillage. In each case, a modified CK plan ($CK_{modified}$) was generated using 5 dose-limiting shells : one at the PIDL, another at intermediate isodose level (50% of prescription dose) for steeper dose fall-off, and the others at low-isodose levels, with an optimized shell-dilation size based on our experience. A Gamma Knife (GK) plan was also produced using the original contour set. Thus, three data sets of dosimetric parameters were generated and compared. Results : There were no differences in the conformity indices among the $CK_{original}$, $CK_{modified}$, and GK plans (mean 1.22, 1.18, and 1.24, respectively; p=0.079) and tumor coverage (mean 99.5%, 99.5%, and 99.4%, respectively; p=0.177), whereas the $CK_{modified}$ plans produced significantly smaller normal tissue volumes receiving 50% of prescription dose than those produced by the $CK_{original}$ plans (p<0.001), with no statistical differences in those volumes compared with GK plans (p=0.345). Conclusion : These results indicate that significantly steeper dose fall-off is able to be achieved in the CK system by optimizing the shell function while maintaining high conformity of dose to tumor.

A Backup Node Based Fault-tolerance Scheme for Coverage Preserving in Wireless Sensor Networks (무선 센서 네트워크에서의 감지범위 보존을 위한 백업 노드 기반 결함 허용 기법)

  • Hahn, Joo-Sun;Ha, Rhan
    • Journal of KIISE:Information Networking
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    • v.36 no.4
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    • pp.339-350
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    • 2009
  • In wireless sensor networks, the limited battery resources of sensor nodes have a direct impact on network lifetime. To reduce unnecessary power consumption, it is often the case that only a minimum number of sensor nodes operate in active mode while the others are kept in sleep mode. In such a case, however, the network service can be easily unreliable if any active node is unable to perform its sensing or communication function because of an unexpected failure. Thus, for achieving reliable sensing, it is important to maintain the sensing level even when some sensor nodes fail. In this paper, we propose a new fault-tolerance scheme, called FCP(Fault-tolerant Coverage Preserving), that gives an efficient way to handle the degradation of the sensing level caused by sensor node failures. In the proposed FCP scheme, a set of backup nodes are pre-designated for each active node to be used to replace the active node in case of its failure. Experimental results show that the FCP scheme provides enhanced performance with reduced overhead in terms of sensing coverage preserving, the number of backup nodes and the amount of control messages. On the average, the percentage of coverage preserving is improved by 87.2% while the additional number of backup nodes and the additional amount of control messages are reduced by 57.6% and 99.5%, respectively, compared with previous fault-tolerance schemes.

Correlation between fish consumption and the risk of mild cognitive impairment in the elderly living in rural areas (농촌지역에 거주하는 노인의 생선 섭취량과 인지기능저하 위험도 간의 상관성)

  • Yu, Areum;Kim, Jihye;Choi, Bo Youl;Kim, Mi Kyung;Yang, Yoonkyoung;Yang, Yoon Jung
    • Journal of Nutrition and Health
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    • v.54 no.2
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    • pp.139-151
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    • 2021
  • Purpose: This study examines the correlation between fish consumption and the risk of mild cognitive impairment in the elderly living in rural areas. Methods: The Yangpyeong cohort data collected from Yangpyeong in July 2009 and August 2010 was used as the data set. Adults greater than or equal to 60 years who have completed the Korean version of the Mini-Mental State Examination (MMSE-KC) were selected for the study. After excluding participants with less than 500 kcal of energy intake (n = 2), a total of 806 adults were enrolled as the final subjects. Cognitive function was assessed using the MMSE-KC, and dietary intake was collected using the quantitative food frequency questionnaire comprising 106 foods or food groups. Results: The educational level, proportion of people who exercise, fruits and vegetable intake, and energy intake, tended to increase with fish intake among men, while increasing age resulted in decreased fish consumption. Among women, the educational level, proportion of subjects who exercise, proportion of subjects currently taking dietary supplements, fruits and vegetable intake, and energy intake, tended to increase with fish consumption, whereas increasing age showed decreasing fish consumption. Increased fish intake resulted in a higher MMSE-KC score after adjusting for the confounding variables in women (p for trend = 0.016), but no significant trend was observed between fish intake and MMSE-KC score in men. Fish intake was inversely related to the risk of mild cognitive impairment after adjusting for covariates in women (Q1 vs. Q4; odds ratio, 0.46 [0.23-0.90]; p for trend = 0.009). Conclusion: This study determined that increased fish consumption is correlated with reduced risk of mild cognitive impairment in the female elderly. Further longitudinal studies with larger samples are required to determine a causal relationship between fish intake and cognitive function.