• Journal of the Korea Society for Simulation
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• v.32 no.4
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• pp.69-76
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• 2023

To improve the financial stability of the National Pension, an appropriate target rate of return should be established based on pension liabilities, and asset allocation policies should be formulated accordingly. The purpose of this study is to calculate the target rate of return considering the contributions of subscribers and the pension benefits, and based on this, derive an asset allocation. To do this, we utilized the internal rate of return methodology to calculate the target rate of return for each cohort. And then, we employed a Monte Carlo simulation-based re-sampling mean-variance model to derive asset allocation for each cohort that satisfy the target rate of return while minimizing risks. Our result shows that the target rate of return for each cohort ranged from 6.4% to 6.85%, and it decreased as the generations advanced due to a decrease in the income replacement rate of the National Pension. Consequently, the allocation of risky assets, such as stocks, was relatively reduced in the portfolios of future generations. This study holds significance in that it departs from the macroeconomic-based asset allocation methodology and proposes investments from an asset-liability management perspective, which considers the characteristics of subscribers' liabilities.

• Journal of Hospice and Palliative Care
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• v.5 no.2
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• pp.136-145
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• 2002

Purpose : This study was designed to develop an instrument that could be used for comprehensive and effective need assessment for patients with cancer. Methods : In the first phase, a conceptual framework for the instrument was established by Wingate & Lackey (1989). In the second phase, the preliminary instrument was drawn up through a review of the literature and in consultation with three professors in Nursing. In the third phase validity and reliability of the preliminary instrument were tested as follows; 1) an expert validity test of the preliminary instrument was done by nine head nurses and charge nurses who had over ten years experience caring for patients with cancer at Wonju Christian Hospital. 2) A construct validity test and reliability test was done for the instrument by 116 staff nurses selected by convience sampling from hospitals located in Kang-Won, Kyoung-Ki, and Choong-Chung Provinces. The collected data were analyzed using SPSS 10.0 WIN program. For the factors of the instrument, factor analysis was used. The reliability of the scale was analyzed by Cronbach's alpha. Results : The results of the experts' test of validity, showed that, of 32 items, only one item had less than 55.4%. It was then deleted and a total of 31 items was selected. On the basis of the results of the factor analysis, the following six components were identified: physiological, informational, spiritual, and emotional needs, available resources, and legal/financial needs. These factors explained 61.8% of the variance. In the factor analysis, the first factor (physiological needs) and the second factor (informational needs) explained 25.4% and 10.9% of the variance respectively, which were major factors for the needs of patients with cancer in Korea. Cronbach' alpha for the scale was .90 indicating internal reliability. Conclusion : This instrument can be effectively utilized for assessment of needs of patients with cancer in Korea. Use of the needs assessment instrument developed in this study will allow nurses to develop nursing interventions that provide comprehensiveness and continuity in meeting the needs of patients with cancer.

• Journal of Animal Science and Technology
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• v.55 no.3
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• pp.165-171
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• 2013

Genomic relationship matrix (GRM) was constructed using whole genome SNP markers of swine and genomic breeding value was estimated by substitution of the numerator relationship matrix (NRM) based on pedigree information to GRM. Genotypes of 40,706 SNP markers from 448 pure Landrace pigs were used in this study and five kinds of GRM construction methods, G05, GMF, GOF, $GOF^*$ and GN, were compared with each other and with NRM. Coefficients of GOF considering each of observed allele frequencies showed the lowest deviation with coefficients of NRM and as coefficients of GMF considering the average minor allele frequency showed huge deviation from coefficients of NRM, movement of mean was expected by methods of allele frequency consideration. All GRM construction methods, except for $GOF^*$, showed normally distributed Mendelian sampling. As the result of breeding value (BV) estimation for days to 90 kg (D90KG) and average back-fat thickness (ABF) using NRM and GRM, correlation between BV of NRM and GRM was the highest by GOF and as genetic variance was overestimated by $GOF^*$, it was confirmed that scale of GRM is closely related with estimation of genetic variance. With the same amount of phenotype information, accuracy of BV based on genomic information was higher than BV based on pedigree information and these symptoms were more obvious for ABF then D90KG. Genetic evaluation of animal using relationship matrix by genomic information could be useful when there is lack of phenotype or relationship and prediction of BV for young animals without phenotype.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.804-811
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• 2010

The lower portion of sloping paddy fields normally contains excessive moisture and the higher water table caused by the inflow of ground water from the upper part of the field resulting in non-uniform water content distribution. Four drainage methods namely Open Ditch, Vinyl Barrier, Pipe Drainage and Tube Bundle for multiple land use were installed within 1-m position from the lower edge of the upper embankment of sloping alluvial paddy fields. Knowledge of the spatial variability of soil water properties is of primary importance for management of agricultural lands. This study was conducted to evaluate the effect of drainage in the soil on spatial variability of soil water content using the geostatistical analysis. The soil water content was collected by a TDR (Time Domain Reflectometry) sensor after the installation of subsurface drainage on regular square grid of 80 m at 20 m paddy field located at Oesan-ri, Buk-myeon, Changwon-si in alluvial slopping paddy fields ($35^{\circ}22^{\prime}$ N, $128^{\circ}35^{\prime}$). In order to obtain the most accurate field information, the sampling grid was divided 3 m by 3 m unit mesh by four drainage types. The results showed that spatial variance of soil water content by subsurface drainage was reduced, though yield of soybean showed the same trends. Value of "sill" of soil water content with semivariogram was 9.7 in Pipe Drainage, 86.2 in Open Ditch, and 66.8 in Vinyl Barrier and 15.7 in Tube Bundle.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.4
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• pp.460-470
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• 1985

Experiments were carried out to evaluate the standard gravity in determining potential kernel size and to determine the effective sampling way by analyzing intra - and inter - plant variations for some source and sink characters using eleven semi-dwarf indica and three japonica cultivars including four semi-dwarf indica nearisogenic lines. Also, additional experiments were conducted to understand yearly variation and variety x year interaction effects for ten characters related to source and sink and to characterize the varietal difference of pre- and post-heading self-competition employing three parental varieties and their F$\sub$5/ progenies in 1982 and 1983. It is desirable to determine the potential kernel size by average kernel wight of rice grains showing above 1.15 specific gravity. There was significant difference in leaf area per tiller, spikelets and sink capacity per panicle among vigorous, intermediate and inferior tillers classified by differentiated order and vigorousness. Although it was difficult to find out any significant difference in grain-fill ratio, ratio of perfectly ripened grain, potential kernel size and sink/source ratio between vigorous and intermediate tillers, there was big difference between them and inferior one. The coefficients of variation within each tiller-group for some characters related to source and sink were larger with the order of vigorous tillers < intermediate one '||'&'||'lt; inferior one, and the average heritability of all characters, evaluated by the ratio of varietal variance (equation omitted) to total variance (equation omitted), were higher with the order of inferior tillers '||'&'||'lt; intemediate one '||'&'||'lt; superior one. Therefore, it is desirable to sample the vigorous tillers to represent the varietal difference of these traits. '82-'83 year variations of three parental cultivars were significant for all traits except for leaf area/tiller, panicles/hill, leaf area index and rough rice yield. The characters showing highly significant variance of variety x year interaction were growth duration from transplanting to heading, leaf area/tiller, sink/source ratio, sink capacity/panicle and grain yield. Generalized yearly response of three parental varieties (Suweon 264, Raegyeong, IR1317-70-l) and their F$\sub$5/ progenies on the 1st and 2nd principal components extracted from ten source and sink characters generally exhibited reduction in both source and sink. However, there were diverse variety x year interactions such as progenies showing similar reaction with their parents and intermediate or recombinational yearly response with little or considerable yearly movement on the four-dimensional planes of the two upper principal components between 1982 and 1983. Sink characters revealing highly significant border effect were grain-fill ratio, spikelets and sink capacity per panicle. Among them the latter two especially showed significant variety x border effect interaction. Self-competition characterized by relative weakness of inside plant's sink characters compared to the border one was more severe during the reproductive stage before heading than maturing stage. Though the larger sink capacity per panicle generally disclosed the severer self-competition, some lines (like Suweon 264) revealed severe self-competition with small sink capacity while a few others showed tender self-competition in spite of big sink capacity per panicle.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.163-172
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• 1989

In order to study spatial variability of soil physical properties accross the land-partitioned boundary on Hwadong silt clay loam soil (Fine clayey, mixed, mesic family of Aquic Hapludalfs), all measured data were analyzed by means of kriging, fractile diagram, smooth frequency distribution, and autocorrelation. Sampling for soil particle size distribution analysis was made at 225 intersections of $15{\times}15$ grid with 10m interval. Field capacity, bulk density and saturated hydraulic conductivity were measured in situ at 594 intersections of $33{\times}18$ grid with 2.5m interval in only $6,000m^2$ reselected from $22,500m^2$ of sampling area for particle size distribution analysis. Sampled or measured soil depths were 0 to 10cm 25 to 35cm and 50 to 60cm at each intersections. The results are summarized as follows: 1. The coefficient of variance (CV) of various physical properties ranges from 4.8 to 128.8%. Saturated hydraulic conductivity is classified into the high variation group with CV greater than 100%, while the low variation group with CV smaller than 10% consists of bulk density. Other properties belong to the medium variation group with CV between 10 and 100%. 2. The appropriate number of soil samples for the determination of various physical properties with error smaller than 10% are calculated as one for bulk density, six for field moisture capacity, 16 for silt, 19 for clay, 69 for sand and 686 for saturated hydraulic conductivity. 3. Smooth frequency distribution and fractile diagram show that saturated hydraulic conductivity is in lognormal distribution while other physical properties are in normal distribution. 4. Serial correlation analysis reveals that the soil physical properties have spatial dependence between two nearest neighbouring grid points. Autocorrelation analysis of physical properties measured between the serial grid points in the direction of south to north following section boundary shows that the zone of influence showing stationarity ranges from 7.5 to 40m. In the direction of east to west across section boundary, the autocorrelogram of many physical properties shows peaks with the periodic interval of 30m, which are similar to the partitioned land width. This reveals that the land-partitioned boundary causes soil variability.

• Journal of Korean Academy of Nursing
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• v.25 no.1
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• pp.61-79
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• 1995

When children are admitted to hospital, they have to adapt to new and unfamiliar stimuli. Children may respond with fear to stimuli such as pain or unfamiliar experiences. One goal of nursing is to help hospitalized children to adapt effectively to their hospital experience. Accordingly, nurses need to assess childrens' fears of their hospital experience to contribute to the planning of care to alleviate these fears. The problem addressed by this study was to identify and measure hospital-related fears(hereafter called HRF) in hospitalized school-aged children. The study was conceptualized with Roy's model. A descriptive qualitative approach was used first, followed by a quantitative approach. This study was conducted from November 30, 1989 to January 12, 1991. The sample consisted of 395 hospitalized school-aged children selected through an allocated sampling technique in nine general hospitals. The HRF questionnaire (three point likert scale ) was developed by a delphi technique. The data were analyzed by an SAS program. Factor analysis was used for the examination of component factors. Differences in the HRF related to demographic variables were examined by t-test, analysis of variance and the Scheffe test. The crude scores of the HRF scale were transformed into T- scores to calculate the standard scores. The results included the following : 1. Forty-four items were derived from 188 statements identifying the childrens' hospital-re-lated fears. These items clustered into 14 factors, fear of injections, operations, bodily harm others' pain, medical rounds, physical examinations, medical staff, disease process, blood and X-rays, drugs and cockroaches, tests, harsh discipline from parents or staff, being absent from school, and separation from family. The 14 factors was classified into four categories,'pain','the unfamiliar','the un-known' and 'separation'. 2. The reliability of the HRF instruments was .92(Cronbach's alpha). In the factor analysis, Cronbach's alpha coefficients for the 14 factors ranged from .84 to .86 and Cronbach's alpha coefficients for the four categories ranged from .70 to .84. Pearson correlation coefficient scores for relationships among the 14 factors ranged from ,11 to .50, and among the four categories, from ,44 to ,63, indicating their relative independence. 3. The total group HRF score ranged from 45 to 130 in a possible range of H to 132, with a mean of 74.51. The fears identified by the children were, in order, injections, harsh discipline by parents or staff, bodily harm, operations, medical staff, disease process, and medical rounds ; the least feared was others' pain. The fear item with the highest mean score was surgery and the lowest was examination by a doctor. HRF scores were higher for girls than for boys, and for grade 1 students than for grade 6 students. HRF scores were lower for children whose fathers were over 40 than for those whose fathers were in the 30 to 39 age group, and whose mothers were over 35 than for those whose mothers were in the 20 to 34 age group. HRF scores were lower when the mother rather than any other person stayed with the child. The expressed fear of pain, the unfamiliar, the un-known and of separation directs nurses' concern to the threat felt by hospitalized children to their concept of self. This study contributes to the assessment of fears of hospitalized children and of stimuli impinging on those fears. Accordingly, nursing practice will be directed to the alleviation of pain, pre-admission orientation to the hospital setting and routines, initiation of information about procedures and experiences and arrangments for mothers to stay with their children. Recommendations were made for further research in different settings and for development and testing of the instrument.

• Korean Journal of Occupational Health Nursing
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• v.7 no.1
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• pp.5-19
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• 1998

This descriptive-correlational study was conducted to identify the major factors affecting health promoting behaviors. 344 workers who employed in four different manutacturing plants in Taegu and Kyungbuk area were selected by convenience sampling method. Data were collected from April let to April 18th, 1998 by ready structured questionaires. The purpose of this study was to offer the basic data for health promotion theory development and health promotion strategy planning. This study was based on Pender's Health Promotion Model and examined three variables health promoting behavior, self-concept and perceived importance of health. The Life Style and Health Habit Assessment scale(LHHA) developed by Pender(1982).The Self-concept scale developed by Choi(1972) and the Health Value scale developed by Wallston, Maides and Wallston(1980) were used for this study. Data was analyzed by percentage, mean. t-test. ANOVA, Pearson Correlation Coefficient, and Stepwise Multiple Regression. The major findings of this study are as follows ; 1. The average level of health promoting behavior practice was 63.2% and possible range was from 62 to 248 point. The mean score of respondent's positive self-concept was 75.8. 81.4% of respondents put a high priority on the importance of health. 2. There was a significant difference between the practice level in the category of general self care and less amount of working hours per day(P=0.000), less amount of working hours per week(P=0.000). There was a significant difference between the practice level in the category of nutrition and age(0.002), marital status(0.000), working hour per day(0.008), working hours per week(0.001), There was a significant difference between the practice level in the category of nutriton and sex(0.000), age(0.000), marital status(0.025), education level(0.000), working hours per day(0.002), working hours per week(0.006). There was a significant difference between the practice level in the category of sleep and rest and age(0.003), marital status(0.002), working hours per day(0.001), working hours per week(0.001). There was a significant difference between the practice level in the category of stress management and working hours per day(0.001), working hours per week(0.002). There was a significant difference between the practice level in the category of self-actualization and working hours per day(0.050). 3. General characteristics influencing the respodent's self-concept were level(P=0.009) and worksite(P=0.001). 4. The results of the hypothesis tests are as follows The first hypothesis, that "The respondent who have more positive self-concept will have higher scores in the practice of health promoting behavior." was supported(r=0.2973, P=0.0001). The second hypothesis that "The respondent who have higher perception level on importance of health will have higher scores in the practice health promoting behavior." was rejected(r=- 0665, P=0.2225). 5. The most important factor that affects health promoting behavior practice was working hours per week(6.0%). The combination of working hours per week, age, education level accounted for 10.0% of the variance in health promoting behavior. In conclusion, the results of this study on industrial workers supported Pender's health promotion model in partial and showed the relatedness between self concept and the practice of health promoting behavior. Further research is required to find factors influencing health promoting behaviors of industrial workers.

• Journal of Intelligence and Information Systems
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• v.17 no.4
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• pp.109-130
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• 2011

One of the major problems in the area of data mining is the size of the data, as most data set has huge volume these days. Streams of data are normally accumulated into data storages or databases. Transactions in internet, mobile devices and ubiquitous environment produce streams of data continuously. Some data set are just buried un-used inside huge data storage due to its huge size. Some data set is quickly lost as soon as it is created as it is not saved due to many reasons. How to use this large size data and to use data on stream efficiently are challenging questions in the study of data mining. Stream data is a data set that is accumulated to the data storage from a data source continuously. The size of this data set, in many cases, becomes increasingly large over time. To mine information from this massive data, it takes too many resources such as storage, money and time. These unique characteristics of the stream data make it difficult and expensive to store all the stream data sets accumulated over time. Otherwise, if one uses only recent or partial of data to mine information or pattern, there can be losses of valuable information, which can be useful. To avoid these problems, this study suggests a method efficiently accumulates information or patterns in the form of rule set over time. A rule set is mined from a data set in stream and this rule set is accumulated into a master rule set storage, which is also a model for real-time decision making. One of the main advantages of this method is that it takes much smaller storage space compared to the traditional method, which saves the whole data set. Another advantage of using this method is that the accumulated rule set is used as a prediction model. Prompt response to the request from users is possible anytime as the rule set is ready anytime to be used to make decisions. This makes real-time decision making possible, which is the greatest advantage of this method. Based on theories of ensemble approaches, combination of many different models can produce better prediction model in performance. The consolidated rule set actually covers all the data set while the traditional sampling approach only covers part of the whole data set. This study uses a stock market data that has a heterogeneous data set as the characteristic of data varies over time. The indexes in stock market data can fluctuate in different situations whenever there is an event influencing the stock market index. Therefore the variance of the values in each variable is large compared to that of the homogeneous data set. Prediction with heterogeneous data set is naturally much more difficult, compared to that of homogeneous data set as it is more difficult to predict in unpredictable situation. This study tests two general mining approaches and compare prediction performances of these two suggested methods with the method we suggest in this study. The first approach is inducing a rule set from the recent data set to predict new data set. The seocnd one is inducing a rule set from all the data which have been accumulated from the beginning every time one has to predict new data set. We found neither of these two is as good as the method of accumulated rule set in its performance. Furthermore, the study shows experiments with different prediction models. The first approach is building a prediction model only with more important rule sets and the second approach is the method using all the rule sets by assigning weights on the rules based on their performance. The second approach shows better performance compared to the first one. The experiments also show that the suggested method in this study can be an efficient approach for mining information and pattern with stream data. This method has a limitation of bounding its application to stock market data. More dynamic real-time steam data set is desirable for the application of this method. There is also another problem in this study. When the number of rules is increasing over time, it has to manage special rules such as redundant rules or conflicting rules efficiently.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.11 no.1
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• pp.79-90
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• 2000

Objective：This study was performed in order to develop a measuring instrument for assessing and predicting delinquent behavior of the adolescents in Korea. Methods：This study was methodological research for developing a questionnaire for measuring delinquent behavior. Through the relevant literature review and personal interview using open-ended question with 12 adolescents in schools, outpatient basis and the juvenile corrective institutions, the author developed a pre-questionnaire with 31 items for assessing delinquent behavior among delinquentprone adolescents. Statistical method employed were test-retest reliability and Cronbach's alpha coefficient for testing reliability and factor analysis for testing validity of this questionnaire, and t-test for mean difference between student adolescents and delinquent adolescents, using SAS program. Subject served for this study consisted of 2,177 adolescents including 1,206 students and 971 delinquent adolescents by proportional stratified random sampling method. Results：1) Three stable factors were emerged and these contributed 52.2% of the variance in the total score. All 31 items loaded above .40 on each factor. 2) Factor I was named as antisocial delinquent behavior(17 items), factor II was named as aggressive delinquent behavior(8 items), and factor III was named as psychopathic delinquent behavior(6 items). 3) Comparison of these 3 factors between student adolescents and delinquent adolescents showed that there was a significant difference in factor Ⅰ(t=-42.91(student), -41.71(delinquent), p=.0001), factor II(t=-34.10(student), -35.72(delinquent), p=.0001), factor III(t=-14.24(student), -14.26 (delinquent), p=.0000), and total score(t=37.02(student), -36.38(delinquent), p=.0001). 4) Internal consistency reliability was tested by Cronbach's ${\alpha}$. Cronbach's ${\alpha}$ was .952 for total 31 items and .950, .866 and .721 for each 3 factors related to delinquent behavior. Conclusions：The author confirmed that this scale can use for measuring delinquent behavior, and hope to make a contribution to screening test and prevention of juvenile delinquency in Korea.