• Title/Summary/Keyword: data-based model

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A Population-based Case-control Study on Risk Factors for Gastric Cardia Cancer in Rural Areas of Linzhou

  • Sun, Chang-Qing;Chang, Yu-Bo;Cui, Ling-Ling;Chen, Jia-Jun;Sun, Nan;Zhang, Wei-Jie;Jia, Xiao-Can;Tian, Yuan;Dai, Li-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.2897-2901
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    • 2013
  • Gastric cancer is the second most common cause of cancer-related deaths in the world. Although certain dietary factors and lifestyles have been suggested to be associated with gastric carcinogenesis, there have been few investigations focusing on rural areas. A case-control study was therefore carried out to investigate the risk factors of gastric cardia cancer (GCC) in rural areas of Linzhou. A total of 470 newly diagnosed cases of GCC and 470 healthy controls were included. Face-to-face interviews were conducted, using a uniform questionnaire containing questions on demographics, per capita income, living habits, dietary habits and family history of tumors. The relationship between putative risk factors and GCC was assessed by odds ratios (OR) and their 95% confidence intervals (95%CI) derived from conditional logistic regression model by the COXREG command using SPSS 12.00. Multivariate logistic regression analysis was used to evaluate simultaneously the effects of multiple factors and other potential confounding factors. Multivariate logistic analysis showed that smoking (OR=1.939, 95%CI:1.097-3.426), alcohol drinking (OR=2.360, 95%CI: 1.292-4.311), hot food consumption (OR=2.034, 95%CI: 1.507-2.745), fast eating (OR=1.616, 95%CI: 1.171-2.230), mouldy food (OR=4.564, 95%CI: 2.682-7.767), leftover food (OR=1.881. 95%CI: 1.324-2.671), and family history of tumor (OR=2.831, 95%CI: 1.588-5.050) were risk factors for GCC. High per capita income (OR=0.709, 95%CI: 0.533-0.942), high education level (OR=0.354, 95%CI: 0.163-0.765), consumption of fresh fruits (OR=0.186, 95%CI: 0.111-0.311) and vegetables (OR=0.243, 95%CI: 0.142-0.415), and high BMI (OR=0.367, 95%CI: 0.242-0.557) were protective factors for GCC. Our data indicate that unhealthy lifestyle and dietary habits might be important contributors to GCC in this population.

The Structure of Tidal Front in the Earstern Yellow Sea in the Summer of 1982 (1982년 하계 서해안 조석전선의 구조)

  • CHOO Hyo Sang;CHO Kyu Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.2
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    • pp.83-91
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    • 1984
  • The formation and structure of tidal front in the eastern part of the Yellow Sea were studied based on the oceanographic data compiled during the periods of $1982{\sim}1983$ and $1966{\sim}1970$. Well-defined fronts occurring in the Yellow Sea in summer mark the boundary between the stratified and vertically mixed regimes. The occurrence of vertically mixed regimes may be interpreted in terms of available turbulent kinematic energy of tidal currents. The tidal frontal regions were determined by horizontal gradients of temperature, salinity and dissolved oxygen, and were verified by water colour and transparency. In summer the tidal fronts were found at depths of $15{\sim}25m$ at about 20 miles from the shore. Potential energy of vortical stratification in the tidal frontal region was 10 $Joule/m^3$. The stratification parameter in the frontal region computed from the numerical tidal model was $S_p=1.0.$ Tidal front is formed in regions with $S_p=1-1.5,$ if surface heat flux are constant. Waters in the stratified region have the layer structures of wind-mixed surface layer, thermocline and tidal-mixed bottom layer. In the vertically mixed region, however, sea water is nearly homogeneous. in winter no distinctive tidal front was seen.

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Effects of Job Stress, Fatigue, Burnout, and Job Satisfaction on Turnover Intention among General Hospital Nurses (종합병원 간호사들의 직무스트레스, 피로, 소진 및 직무만족도가 이직의도에 미치는 영향)

  • Lim, Yeon-Hee;Cho, Young-Chae
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.6
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    • pp.264-274
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    • 2018
  • This study constructed a prediction model based on covariance structure to identify the causal relationship between job stress, fatigue, burnout, and job satisfaction on turnover intention in nurses working in general hospitals. The study subjects were 648 nurses at a general hospital in D city. Data collection was surveyed by using self-administered questionnaires structured during the period from November 1, 2016 to December 31, 2016. As a result, the level of turnover intention was significantly higher in the group showing higher job stress, fatigue, and burnout and significantly higher in the group showing lower job satisfaction. The turnover intention of subjects showed a significant positive correlation with job stress, fatigue, and burnout but showed a negative correlation with job satisfaction. As a result of covariance structure analysis, job stress had greater influence on turnover intention than fatigue, burnout, and job satisfaction. Higher job stress, fatigue, and burnout and lower job satisfaction were associated with increased turnover intention. The results of this study show that the turnover intention of general hospital nurses is significantly related to job stress, fatigue, burnout, and job satisfaction. In particular, job stress had a greater effect on turnover than fatigue, burnout, and job satisfaction. Therefore, in order to lower the turnover intention of general hospital nurses, it is necessary to seek ways to mitigate job stress.

User-centered information service and a n.0, pplication of sense-making theory (이용자 중심 정보서비스와 Sense-making 이론의 적용)

  • ;Noh, Jin-Goo
    • Journal of Korean Library and Information Science Society
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    • v.28
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    • pp.447-475
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    • 1998
  • We are seeing a shift of the focus of information service from system-centered(data-centered or intermediary-centered) a n.0, pproach to user-centered a n.0, pproach. Sense-making theory is one of the user- centered a n.0, pproaches. This study focused on user-centered information service paradigm concepts of Dervin's sense-making theory and interpreting sense-making theory in the practical context of library services. The sense-making theory is basically a cognitive a n.0, pproach to information-seeking, in that it recognizes information as something that involves internal cognitive processes. The user of information becomes the focus in this sense-making model. The sense-making theory sees information as subjective, situational, and cognitive. It focuses on understanding information within specific contexts and on understanding how information needs develop and how they are satisfied. It regards the user not as a passive receive of external information but as the center in a active, ongoing process of change. It related to the information needs of users. Dervin's method for studying information needs employs the 'situation-gap-use' metaphor. All information needs stem from a discontinuity or 'gap! in one's knowledge. Dervin believes that information needs can be addressed by understanding the process that each individual goes through in experiencing a gap, in trying to resolve it, and in gaining something (especially new knowledge) from the experience. Sense-making is a process; 'sense' is the product of this process. Sense includes 'knowledge'. However, it includes a host of other subjective factors that reflect an individual's interpretations of a situation including intuitions, opinions, hunches, effective responses, evaluations, questions, etc. For several reasons, however, difficulties are encountered if one attempts a more substantial assessment of the theory. First, it has not yet crystallized into a well-defined theory. Secondly, though the theory has aroused general interest, e.g. within LIS, detailed discussion of its strong and weak points is still lacking. A third source of difficulty is that the basic assumptions of the theory have been explicated metaphorically. If sense-making theory is to be really useful, it needs to be interpreted for library settings. But we have found no attempt to construct an information service based on the theory. Because the research tradition is still relatively young, there are many unanswered questions connected, e.g. with the design of information systems. In any case, e.g. intermediary access systems would be more efficient and effective it their planning could be founded on the user-centered a n.0, pproach.

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VRIFA: A Prediction and Nonlinear SVM Visualization Tool using LRBF kernel and Nomogram (VRIFA: LRBF 커널과 Nomogram을 이용한 예측 및 비선형 SVM 시각화도구)

  • Kim, Sung-Chul;Yu, Hwan-Jo
    • Journal of Korea Multimedia Society
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    • v.13 no.5
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    • pp.722-729
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    • 2010
  • Prediction problems are widely used in medical domains. For example, computer aided diagnosis or prognosis is a key component in a CDSS (Clinical Decision Support System). SVMs with nonlinear kernels like RBF kernels, have shown superior accuracy in prediction problems. However, they are not preferred by physicians for medical prediction problems because nonlinear SVMs are difficult to visualize, thus it is hard to provide intuitive interpretation of prediction results to physicians. Nomogram was proposed to visualize SVM classification models. However, it cannot visualize nonlinear SVM models. Localized Radial Basis Function (LRBF) was proposed which shows comparable accuracy as the RBF kernel while the LRBF kernel is easier to interpret since it can be linearly decomposed. This paper presents a new tool named VRIFA, which integrates the nomogram and LRBF kernel to provide users with an interactive visualization of nonlinear SVM models, VRIFA visualizes the internal structure of nonlinear SVM models showing the effect of each feature, the magnitude of the effect, and the change at the prediction output. VRIFA also performs nomogram-based feature selection while training a model in order to remove noise or redundant features and improve the prediction accuracy. The area under the ROC curve (AUC) can be used to evaluate the prediction result when the data set is highly imbalanced. The tool can be used by biomedical researchers for computer-aided diagnosis and risk factor analysis for diseases.

The Determinants of New Supply in the Seoul Office Market and their Dynamic Relationship (서울 오피스 신규 공급 결정요인과 동태적 관계분석)

  • Yang, Hye-Seon;Kang, Chang-Deok
    • Journal of Cadastre & Land InformatiX
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    • v.47 no.2
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    • pp.159-174
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    • 2017
  • The long-term imbalances between supply and demand in office market can weaken urban growth since excessive supply of offices led to office market instability and excessive demand of offices weakens growth of urban industry. Recently, there have been a lot of new large-scale supplies, which increased volatility in Seoul office market. Nevertheless, new supply of Seoul office has not been fully examined. Given this, the focus of this article was on confirming the influences of profitability, replacement cost, and demand on new office supplies in Seoul. In examining those influences, another focus was on their relative influences over time. For these purposes, we analyzed quarterly data of Seoul office market between 2003 and 2015 using a vector error correction model (VECM). As a result, in terms of the influences on the current new supply, the impact of supply before the first quarter was negative, while that of office employment before the first quarter was positive. Also, that of interest rate before the second quarter was positive, while those of cap rate before the first quarter and cap rate before the second quarter were negative. Based on the findings, it is suggested that prediction models on Seoul offices need to be developed considering the influences of profitability, replacement cost, and demand on new office supplies in Seoul.

Water Quality Modelling of the Keum River - Effect of Yongdam Dam (용담댐의 영향분석을 위한 금강의 수질모델링)

  • Lee, Eun-Hyung;Seo, Dong-Il
    • Journal of Korea Water Resources Association
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    • v.35 no.5
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    • pp.525-539
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    • 2002
  • Effects of Yongdam Dam discharge conditions on water quality of the Keum River and Daechung Lake inflow were analyzed for various scenarios using WASP5 water quality model. Three different groups of scenarios were tested: 1) Two different weather conditions; the lowest flow year and the highest flow year since the beginning of Daechung Dam operation in 1981, 2) Fine discharge flow rates; 5.4, 8.9, 12.4, 16.4 ㎥/s and field observed flow during the study period, 3) Three conditions of discharge water quality; first grade, second grade by Korean water quality standard and field observed water quality. Effect of changes in Yongdam Dam discharges was greater for dry year. The increase of discharge from the Yongdam Dam will improve water quality of downstream areas only when the water quality of the discharge is equal or better than that of downstream areas. Field observed water qualify data show that BOD concentrations are lower than first grade level but TN and TP concentrations are exceeding 5th and 3rd grade level in Korean standard, respectively. Considering that nutrient control methods in watershed areas of Yongdam dam are limited, it is expected that nutrient concentrations from Yongdam Dam discharge will be higher than 2nd grade water quality standard level. Therefore, it would be important to develop practical management strategies in the watershed area of Yongdam Dam based on field conditions for conservation of water quality in downstream areas.

Impact Assessment of Climate Change on Drought Risk (기후변화가 가뭄 위험성에 미치는 영향 평가)

  • Kim, Byung-Sik;Kwon, Hyun-Han;Kim, Hung-Soo
    • Journal of Wetlands Research
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    • v.13 no.1
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    • pp.1-11
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    • 2011
  • A chronic drought stress has been imposed during non-rainy season(from winter to spring) since 1990s. We faced the most significant water crisis in 2001, and the drought was characterized by sultry weather and severe drought on a national scale. It has been widely acknowledged that the drought related damage is 2-3 times serious than floods. In the list of the world's largest natural disaster compiled by NOAA, 4 of the top 5 disasters are droughts. And according to the analysis from the NDMC report, the drought has the highest annual average damage among all the disasters. There was a very serious impact on the economic such as rising consumer price during the 2001 spring drought in Korea. There has been flood prevention measures implemented at national-level but for mitigation of droughts, there are only plans aimed at emergency (short-term) restoration rather than the comprehensive preventive measures. In addition, there is a lack of a clear set of indicators to express drought situation objectively, and therefore it is important and urgent to begin a systematic study. In this study, a nonstationary downscaling model using RCM based climate change scenario was first applied to simulate precipitation, and the simulated precipitation data was used to derive Standardized Precipitation Index (SPI). The SPI under climate change was used to evaluate the spatio-temporal variability of drought through principal component analysis at three different time scales which are 2015, 2045 and 2075. It was found that spatio-temporal variability is likely to modulate with climate change.

The Estimation of Shear Stress in Uniform and Nonuniform Flow by the Entropy Concept (엔트로피 개념을 이용한 개수로에서 등류 및 부등류 흐름의 전단응력 산정)

  • Choo, Yeon Moon;Choo, Tai Ho;Yang, Da Un;Kim, Joong Hoon
    • Journal of Wetlands Research
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    • v.19 no.2
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    • pp.202-210
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    • 2017
  • Shear stress is one of the most important mechanical factors used in various fields and is important for the design of artificial channels. Current shear stresses have been used in the past, but there are factors that are difficult to actually measure or calculate, such as bed shear stress and energy slope in the equation used. In particular, the energy slope is a very difficult factor to estimate, and it is difficult to estimate the slope and flow velocity of the boundary layer although the energy slope can be used to obtain the shear stress distribution. In addition, the bed shear stress among the shear stress distribution is very difficult to measure directly, and the research is somewhat slower than the velocity. In this study, we have studied the simple calculation of the average flow velocity and the shear stress distribution using entropy M without reflecting the energy gradient, and we used existing laboratory data to demonstrate the utility of the applied equation. The stress distribution in the graphs was comparatively analyzed. In the case of the uniform flow and the non-uniform flow, the correlation coefficient was almost identical to 0.930-0.998.

Altitudinal Pattern of Evapotranspiration and Water Need for Upland Crops in Jeju Island (제주도 지역의 고도에 따른 증발산량 및 용수량 특성 평가)

  • Kim, Chul Gyum;Kim, Nam Won
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.915-923
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    • 2015
  • A method of estimating irrigation water need based on water balance and net water consumption concept is proposed, and applied to four watersheds in order to assess the regional and altitudinal characteristics of evapotranspiration and water need for upland crops in Jeju Island. Potential and actual evapotranspiration, and net water need were calculated during the period 1992 to 2013 using SWAT-K watershed model. The annual potential evapotranspiration decreased linearly with increasing elevation, while actual evapotranspiration showed increase with elevation to 400 m around and gradual decrease at higher elevation due to vegetation species, water availability, and cold limitation. Altitudinal pattern of net water need showed linear decrease with increasing elevation for three watersheds (Han-cheon, Cheonmi-cheon, and Oedo-cheon), and annual values of net water need for upland areas (below 200 m in elevation) were 559~680mm/yr. The comparison between actual pumping rate from wells and net water need for irrigation area showed that the amount of pumping water significantly increased during summer season (June to August), while net water need for crop cultivation relatively decreased during this period. To ensure these results, more water use data from pumping wells and additional watersheds should be investigated in the next study.