• Asia pacific journal of information systems
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• v.24 no.2
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• pp.233-253
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• 2014

Can the stock market really be predicted? Stock market prediction has attracted much attention from many fields including business, economics, statistics, and mathematics. Early research on stock market prediction was based on random walk theory (RWT) and the efficient market hypothesis (EMH). According to the EMH, stock market are largely driven by new information rather than present and past prices. Since it is unpredictable, stock market will follow a random walk. Even though these theories, Schumaker [2010] asserted that people keep trying to predict the stock market by using artificial intelligence, statistical estimates, and mathematical models. Mathematical approaches include Percolation Methods, Log-Periodic Oscillations and Wavelet Transforms to model future prices. Examples of artificial intelligence approaches that deals with optimization and machine learning are Genetic Algorithms, Support Vector Machines (SVM) and Neural Networks. Statistical approaches typically predicts the future by using past stock market data. Recently, financial engineers have started to predict the stock prices movement pattern by using the SNS data. SNS is the place where peoples opinions and ideas are freely flow and affect others' beliefs on certain things. Through word-of-mouth in SNS, people share product usage experiences, subjective feelings, and commonly accompanying sentiment or mood with others. An increasing number of empirical analyses of sentiment and mood are based on textual collections of public user generated data on the web. The Opinion mining is one domain of the data mining fields extracting public opinions exposed in SNS by utilizing data mining. There have been many studies on the issues of opinion mining from Web sources such as product reviews, forum posts and blogs. In relation to this literatures, we are trying to understand the effects of SNS exposures of firms on stock prices in Korea. Similarly to Bollen et al. [2011], we empirically analyze the impact of SNS exposures on stock return rates. We use Social Metrics by Daum Soft, an SNS big data analysis company in Korea. Social Metrics provides trends and public opinions in Twitter and blogs by using natural language process and analysis tools. It collects the sentences circulated in the Twitter in real time, and breaks down these sentences into the word units and then extracts keywords. In this study, we classify firms' exposures in SNS into two groups: positive and negative. To test the correlation and causation relationship between SNS exposures and stock price returns, we first collect 252 firms' stock prices and KRX100 index in the Korea Stock Exchange (KRX) from May 25, 2012 to September 1, 2012. We also gather the public attitudes (positive, negative) about these firms from Social Metrics over the same period of time. We conduct regression analysis between stock prices and the number of SNS exposures. Having checked the correlation between the two variables, we perform Granger causality test to see the causation direction between the two variables. The research result is that the number of total SNS exposures is positively related with stock market returns. The number of positive mentions of has also positive relationship with stock market returns. Contrarily, the number of negative mentions has negative relationship with stock market returns, but this relationship is statistically not significant. This means that the impact of positive mentions is statistically bigger than the impact of negative mentions. We also investigate whether the impacts are moderated by industry type and firm's size. We find that the SNS exposures impacts are bigger for IT firms than for non-IT firms, and bigger for small sized firms than for large sized firms. The results of Granger causality test shows change of stock price return is caused by SNS exposures, while the causation of the other way round is not significant. Therefore the correlation relationship between SNS exposures and stock prices has uni-direction causality. The more a firm is exposed in SNS, the more is the stock price likely to increase, while stock price changes may not cause more SNS mentions.

• Journal of Intelligence and Information Systems
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• v.17 no.1
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• pp.127-138
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• 2011

The core service of most research portal sites is providing relevant research papers to various researchers that match their research interests. This kind of service may only be effective and easy to use when a user can provide correct and concrete information about a paper such as the title, authors, and keywords. However, unfortunately, most users of this service are not acquainted with concrete bibliographic information. It implies that most users inevitably experience repeated trial and error attempts of keyword-based search. Especially, retrieving a relevant research paper is more difficult when a user is novice in the research domain and does not know appropriate keywords. In this case, a user should perform iterative searches as follows : i) perform an initial search with an arbitrary keyword, ii) acquire related keywords from the retrieved papers, and iii) perform another search again with the acquired keywords. This usage pattern implies that the level of service quality and user satisfaction of a portal site are strongly affected by the level of keyword management and searching mechanism. To overcome this kind of inefficiency, some leading research portal sites adopt the association rule mining-based keyword recommendation service that is similar to the product recommendation of online shopping malls. However, keyword recommendation only based on association analysis has limitation that it can show only a simple and direct relationship between two keywords. In other words, the association analysis itself is unable to present the complex relationships among many keywords in some adjacent research areas. To overcome this limitation, we propose the hybrid approach for establishing association network among keywords used in research papers. The keyword association network can be established by the following phases : i) a set of keywords specified in a certain paper are regarded as co-purchased items, ii) perform association analysis for the keywords and extract frequent patterns of keywords that satisfy predefined thresholds of confidence, support, and lift, and iii) schematize the frequent keyword patterns as a network to show the core keywords of each research area and connecting keywords among two or more research areas. To estimate the practical application of our approach, we performed a simple experiment with 600 keywords. The keywords are extracted from 131 research papers published in five prominent Korean journals in 2009. In the experiment, we used the SAS Enterprise Miner for association analysis and the R software for social network analysis. As the final outcome, we presented a network diagram and a cluster dendrogram for the keyword association network. We summarized the results in Section 4 of this paper. The main contribution of our proposed approach can be found in the following aspects : i) the keyword network can provide an initial roadmap of a research area to researchers who are novice in the domain, ii) a researcher can grasp the distribution of many keywords neighboring to a certain keyword, and iii) researchers can get some idea for converging different research areas by observing connecting keywords in the keyword association network. Further studies should include the following. First, the current version of our approach does not implement a standard meta-dictionary. For practical use, homonyms, synonyms, and multilingual problems should be resolved with a standard meta-dictionary. Additionally, more clear guidelines for clustering research areas and defining core and connecting keywords should be provided. Finally, intensive experiments not only on Korean research papers but also on international papers should be performed in further studies.

• Korean Journal of Agricultural Science
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• v.18 no.2
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• pp.164-179
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• 1991

Korean agriculture has encountered two problems. One is internal income disparity between rural and urbarn area and the other is external Uruguay Round trade problems as an abolition of direct and indirect import barriers, reduction in export subsidies and to reduce internal price supports. These problems will be brought severe farm problems such as decreasing farm household income and repressing agricultural growth in the near future. Considering the above inevitable facts Korean government has implemented several development projects such as rural industrial area development project, rural special production area development project, leisuresight seeing farm development project, traditional food development project, unskilled labor training project for off-farm employment and so on, to increase farm household income through off-farm income increase. This study was mainly concentrated on the identification of operational problems and post evaluation of the rural special production area development projects which aimed at increasing non-farm incomes and giving employment opportunity for rural farmers in small factories processing regional special farm products and mine products. The main findings and problems to be solved for the successful project implementation are as followed ; 1. Total number of the special production area development projects as of the end of 1991 was amount to 138, and total number of farm household participated were estimated at 2,079, and total amount of off-farm income per farm household was reached to 3,011 thousand won. 2. The total number of processed special products have increased from 21 items in 1981 to 56 items in 1991. On the other hand the total number of farm household participated in the projects have decreased from 2,518 to 2,079 during same period. 3. Total amount of investment for the projects has increased from 1,429 million won in 1981 to 24,760 million won in 1991 but the rate of G'T loan of the total investment has reduced from 24.5% to 5.2% during same period. 4. 138 special production area development project are classified into 6 kinds of commodity groups such as 19 of general industrial good production areas, 52 of folks-industrial art objects production areas, 39 of food processing areas, 9 of fiber and texstile processing areas, 18 of agricultural and fishery inputs processing areas and 1 of stone processing area. 5. The total production value in 1990 was estimated 20,169 million won of which export was amount to 2,627 million won. 6. The finacial rate of return of the UNGOK KUGIJA Tea processing Project operated by UNGOK coops and BAKSAN ginseng tea processing project were estimated at 45.4% (B/C Ratio=1.17, NPV=152.5 million won) and 17.7% (B/C Ratio=1.12, NPV=120.2 million won) respectively. 7. More favorite terms and condition of the loan including collateral problems have to be given to farmers participated. Heavy investment and G'T subsidy policies should be started for the successful project implementation anf farm household income increase. 8. To expand market demand of the rural special goods G'T have to provide special program of TV or other mass media for commodity propaganda and the total cost concerned must be supported by G'T subsidy. 9. The special farm products as GUGUJA,MOSI'Ramie', Ginseng. SOGOKJU,HEMP,Mushroom.DUGYUNJU and Chesnut processing projects have to be propelled and expanded for off-farm income increase in Chung Nam Province. 10. Direct operational pattern of the special production area by coops is more favorable to farmers and recommendable considering with off-farm income increase and market demand creation throughout Korea. 11. In rural area, special organizations for project appraisal are not exist. Accordingly special training program, project appraisal, formulation and preparation for civil servants concerned have to be prepared for project selection and sound implementation under limited budget and financial support.

• Biomedical Science Letters
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• v.2 no.2
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• pp.167-174
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• 1996

Alcoholics increased susceptibility to microbial infection that is associated with decreased immunity. but there has been little experimental evidence to support alcoholics-induced increase of microbial infection directly in non-specific immunity. Therefore, we were used the method of phagocytic-plaque including all the stimulating factors for the phagocytosis, subtypes of lymphocytes and T-lymphocyte proliferation. The experimental groups were divided into 3 groups: (1) alcoholics who were hospitalized less than 1 week (newly hospitalized alcoholics), (2) alcoholics who were hospitalized more than 2 weeks (old hospitalized alcoholics), (3) healthy blood donors. We have studied 98 alcoholics and 35 healthy blood donors and control groups. A physician has checked the biological markers and diagnosed the body-condition alcoholics. The immunity and non-specific immunity on the alcoholics were analyzed by using the simultest kit and flow cytometry. Proliferation of the lymphocytes was analyzed by the phytohemmagglutinine mitogen. Phagocytosis and migration properties of leukocytes were identified on the layer formed by Staphylococcus aureus Cowan I strain. Biological markers of alcoholics and control groups, by such as blood glucose, ${\gamma}$-glutamyl transpeptidase and mean corpuscular volumes of red blood cells, were determined by biochemical and hematological methods. Compared with control groups, cluster of differentiation (CD)3+, CD8+ and CD19+ in alcoholic were more decreased except CD4+/CD8+ ratio. Proliferation of the T-lymphocytes, phagocytosis and migration properties of the leukocytes in alcoholics were decreased compared with those of control groups. According to the results observed in our experiment, they can be summerized as follows: 1, Cellular, humoral and non-specific immunities, are markedly decreased in alcoholics than those in control groups. 2. It is inferred that Phagocytic plaque formation is a very useful method to evaluate phagocytosis and migration properties of the alcoholic leukocytes 3. It is thought that the subtypes of lymphocytes, especially CD4+/CD8+ ratio, are essential methods to analyzed the alcoholic immunity. 4. Specific and non-specific immunity on the old hospitalized alcoholics was slightly increased, which depends upon the alcoholic medication.

• The Korean Nurse
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• v.29 no.4
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• pp.51-72
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• 1990

The purpose of this study was to determine whether Severance Hospice Home Care Pro gram was able to meet its objectives. This was done in order to show in detail the effects of hospice home care on the quality of life of terminally ill patients and to provide rationale for setting up more hospice home care programs in korea. The results of the study were as follows: The subjects of the study were 100 terminally ill patients who hnd died 'while in the hospice program and 64 family members who were registered with Severance Hospice Home Care Program between march 1988 and Feb. 1990. The nursing needs of these terminally ill patients were assessed by the nursing records of these patients. The need for pain control(82%) was the highest nursing need so far as the physical aspects were concerned. This was followed by poor appetite(37%), 8 dyspnea(34%), nausea and vomiting(30%) in that order of frequency. In reqard to spiritual needs, the need for religious' support was also high at 72%. Their main psychological symptoms were anxiety and fear(34% ). Burn-out was a major problem for 44% of the family members. The psychological process experiencel by the terminal ill patients was compared to the dying process, described by Kiibler Ross. In comparison of the five stages outlined by kubler Ross with the dying process of the subjects it was found that the subjects not only experienced the five stages but also experienced denial and doubt-fulness or denial with acceptance or acceptance with the expectation of a miracle. But rather than acceptance of the dying process, giving up was a frequent end point of the psychological process, of the subjects. However, when the combination of states was observed, most of the patients reached the state of acceptance in the dying process. It was difficult to identify a definite pattern of change in the psychological process of the subjects. Also it was difficult to identify the factors that influenced the psychological process. The symptoms of the terminally j]] subjects just before dying, that is, 3-4 days before dying included apparent signs of dying. These were a reduction of intake(77%), reduction of the amount of urination(63%), increase in sleeping time (64%) and acceptance of dying by patients and their families who had been unaccepting be before that time(66%). The primary care givers(family member's) degree of satisfaction with the care given to the patient by the hospice was 88.7%. The results of this study show that Severance Hospice Home Care Program had a positie effeet on the quality of life of the terminally ill patients and their family members as they faced the death of the patient. It can be seen from this study that there is an urgent need to extend hospice programs - in order to provide quality of care for terminally ill patient and their families. Based upon the reesults of this study several suggestions are presente as follows: 1) A follow up study should be carried out to identify the dying process as it is unique to Korea. 2) A comparison should be made of other hospice care programs. 3) A comparison study should- be made with subjects who do not receive any hospice care as compared to those who do by use of an experimental and control group methodology. 4) There is a need to determine a scientific method to adequeto measure the interventions carried out to meet the hospice patients nursing care needs. 5) A study should be made using quality research methodology to evaluate effects of hospiec care from the patients, their family members and the nurrse's perspective.

• Journal of Preventive Medicine and Public Health
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• v.29 no.1 s.52
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• pp.79-90
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• 1996

The purpose of the study was to determine factors influencing compliance with anti-tuberculosis therapy. The study subjects were 104 tuberculosis patients who have received the initial treatment in 3 health centers of Kyongju-City, Dalseong-Gun in Teagu and Kumi-City. Data were collected between September and October 1995. The patients were classified into the improved group and the non-improved group according to outcomes of 3 month treatment with short-term therapeutic regimen. To find factors influencing compliance with anti-tuberculosis therapy, multiple logistic regression was made. There was no significant differences between the improved group and the non-improved group in sex, age, education level, occupation, family pattern, and habitual change regarding smoking and drinking. The level of knowledge about anti-tuberculosis therapy in the improved group was significantly higher than the non-improved group(p<0.01). Multiple logistic regression analysis revealed that family support for not forgetting medication (p<0.05) wis a predictor of improvement and knowledge about anti-tuberculosis therapy(p=0.054), regularity of medication(p=0.062), and consultation to family, doctor and nurse(p=0.075) were marginal predictors of improvement. Treatment must be given to every patient confirmed as having tuberculosis and must be given free of charge to the patients. The requirements for adequate chemotherapy are prescribed in the correct dosage and taken regularly by the patient for a sufficient period to prevent relapse of the disease after cure. It is suggested that education to the patients should be reinforced and connectedness between patients and tuberculosis control workers and family should be solidated.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.9 no.2
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• pp.162-168
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• 2006

Purpose: Microbial colonization of the intestine begins just after birth and development of the normal flora is a gradual process. The first bacteria colonizing the intestine in newborns are Staphylococcus, Enterobacteriaceae and Streptococcus. For several days after birth, the number of Bifidobacterium spp. increase. The aim of this study was to investigate the changes of microflora for seven days postnatally in neonatal stool. Methods: Fifteen neonates (breast : formula : mixed feeding 1 : 8 : 6, vaginal delivery : cesarean section 3 : 12) who were born at the Kangdong Sacred Heart Hospital, Hallym University were enrolled. First meconium and stools of postnatal 1-, 3-, and 7-day were innoculated. Blood agar plates for total aerobes, trypton bile X-glucuronide agar for E. coli, phenylethyl alcohol agar for gram positive anaerobes, MRS agar for Lactobacillus spp., bifidobacterium selective agar for Bifidobacterium spp. and cefoxitin-cycloserine-fructose agar for Clostridium difficile were used in the general incubator ($CO_2$ free incubator), $CO_2$ incubator or the anaerobic chamber for 48 or 72 hours at $37^{\circ}C$ and then colony forming units were counted. Results: No microflora was identified in the first meconium. Total aerobes, E. coli, and gram positive anaerobes were significantly increased with advancing postnatal days. In only one baby, Lactobacillus acidophilus was detected $2{\times}10^5CFU/g$ in the seven-day stool. Bifidobacterium spp. was detected in two babies. Clostridium difficile was not detected during the seven days. There were no significant differences in the bowel flora depending on the delivery pattern and feeding method. Conclusion: This study shows many changes in the intestinal normal flora in neonatal stool during seven days postnatally. If these findings are confirmed with larger studies, the data may be preliminary findings to support use of probiotics in neonates.

• Journal of KIISE:Information Networking
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• v.29 no.6
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• pp.595-612
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• 2002

One of the most important issues in guaranteeing the high degree of QoS on mobile computing is how to reduce hand-off drops caused by lack of available bandwidth in a new cell. Each cell can request bandwidth reservation to its adjacent cells for hand-off calls. This reserved bandwidth can be used only for hand-offs, not for new calls. It is also important to determine how much of bandwidth should be reserved for hand-off calls because reserving too much would increase the probability of a new call being blocked. Therefore, it is essential to develop a new mechanism to provide QoS guarantee on a mobile computing environment by reserving an appropriate amount of bandwidth and call admission control. In this paper. bandwidth reservation and call admission control mechanisms are proposed to guarantee a consistent QoS for multimedia traffics on a mobile computing environment. For an appropriate bandwidth reservation, we propose an adaptive bandwidth reservation mechanism based on an MPP and a 2-tier cell structure. The former is used to predict a next move of the client while the latter to apply our mechanism only to the client with a high hand-off probability. We also propose a call admission control that performs call admission test only on PNC(Predicted Next Cell) of a client and its current cell. In order to minimize a waste of bandwidth caused by an erroneous prediction of client's location, we utilize a common pool and QoS adaptation scheme. In order evaluate the performance of our call admission control mechanism, we measure the metrics such as the blocking probability of new calls, dropping probability of hand-off calls, and bandwidth utilization. The simulation results show that the performance of our mechanism is superior to that of the existing mechanisms such as NR-CAT2, FR-CAT2, and AR-CAT2.

• Journal of agricultural medicine and community health
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• v.23 no.1
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• pp.65-78
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• 1998

This study was conducted to find out the factors which have an effect on the rural aged's natural history by disability in Activities of Daily Living(ADL) and ADL decline with 475 old people which were chosen except the dead 90 and unconfirmable 56 old people by performing follow-up survey for 4 years since 1993 on the basis of presurveyed data about 621 home old people over 60 years residing in 13 villages at Kangdong-myon, Kyongju-city, Kyongsangbuk-do Province, Korea. Such activities of daily living as bathing, dressing, going to toilet, transfer, feeding and continence were examined. 1. In the follow-up survey for 4 years, the ADL distribution of the dead was remarkably lower than the subject group. 2. It was also shown in the 4-year follow-up survey that 82.1% of high ADL group maintained high ADL while 77.8% of low ADL group died within 4 years. 3. The occurrence percentage of disabilities of each group by ADL item for 4 years appeared high in such an order as bathing, continence, dressing, going to toilet, transfer and feeding. 6.7%(8.1% for female and 4.6% for male) of the old people who were the high ADL group at the time of the first survey had disabilities that occurred after 4 years. 4. In the change of ADL according to general characteristics used to analyse the factors which have an effect on ADL decline, there was a significant difference in age and job, that is, the jobless old people had the higher degree of ADL decline. In the change of ADL according to behavioral pattern, for the male old people there was a significant difference in support of living expenses and subjective health condition. In this case, the degree of ADL decline was higher if they depended on their sons & daughters or spouses and felt that they were not healthy.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.11 no.1
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• pp.5-13
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• 2004

The home health care industry has grown rapidly and can be expected to continue to grow in the foreseeable future. Home health care refers to the practice of nursing applied to clients with a health condition in the clients place of residence. clients and their designated care givers are the focus at home health nursing practice. The goal of care is to initiate. manage and evaluate the resources needed to promote the clients optimal level of well-being and function. Nursing activities necessary to achieve this goal may warrant preventive maintenance and restorative emphases to prevent potential problems from developing. Many project program were suggested home health care model for Korea's health care system and policy direction for expansion and establishment of home health care .But the aim of this paper is to provide on overview for theoretical frame work in home health care. Theories and conceptual frameworks or models are important nursing because they define and guide the boundaries of professional practice and identify key nurse-patient-caregiver relationships that emerge with caring. Following is the research with an investigation of the literature review in the University of Arizona international medline database, In conclusion, are as followers: First, many nursing theorists have had a tremendous impact on nursing practice. the following highlights those nursing theorists that are particularly helpful in understanding home health care. 1. Florence Nightingale : Our earliest theoretical legacy. Nightingale's believes are reflected in basic infection control practice such as hand washing and infectious waste disposal and are key nursing interventions in home care. 2. Martha Roger's :Science of unitary human beings theory. Rorger's believed that the focus of shared. non invasive healing modelities is the human environmental field rather than direct physical care. These modelities continue to evolve as our awareness (reflecting greater diversity, faster rhythms, motions, and ways of knowing) transcends time and space, allowing individuals to get in touch with their integral nature of unbroken wholeness. On people as ever changing energy fields have special relevance in home care especially with hospice and palliative care applications. 3. Madeline Leininger's; Transcultural nursing theory. Home care nurses move through a variety of communities and often care for patients from different cultural back grounds. Therefore Leininger's work has a good that with home care because home care nursing practice is very culturally focused. 4. Dorothea Orem's : Self care deficit theory. Orem's theory views care as something to be performed by both nurses and patients. The role of the nurse is to provide education and support that help patients acquire the necessary activities to perform self-care. Orem's theory is foundational to have care because it begins to truly acknowledge the role of the patient in managing his or her own health. which is referred to as self-care. 5. Margaret Neuman's; Health as expending consciousness theory. Neuman believes that health compasses disease and reflects an underlying pattern of person-environment interaction. A key application of 'Neuman's work to home care is for nurses to understand that health and illness do not necessarily exist at opposite ends of a continuum. 6. Jean Watson's: Theory of human caring. Watson's theory of human caring in nursing proposes human caring as the moral ideal of nursing. Nurses participate human caring to protect, enhance and preserve humanity by assisting individuals to fing meaning in illness. pain and existence and to help others gain self knowledge. self control. and self healing such thinking lends richness to theory development. as well as clinical practice in home care. Second, Robin Rice : Dynamic self determination for self care. (A theoretical framework for home care) Dynamical self determination for self care can be useful to home care nurses in a variety of ways. As research tool it can be reflected in the interview process when the home visit. The home care nurse's role is that of facilitator of patient self-determination for self care through numerous strategies. including patient education and case management.