• 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.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.341-350
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• 2009

The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of $10^6\;CFU$, $10^7\;CFU$, $2{\times}10^7\;CFU$, $10^8\;CFU$ of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed $1^{st}$ week, $2^{nd}$, $3^{rd}$ and $4^{th}$ weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries.

• The Korean Journal of Mycology
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• v.29 no.1
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• pp.1-8
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• 2001

To examine the structural properties of the proteoglycan (GMPG, Ganoderma lucidum mycelial proteoglycan) obtained from mycelia in Ganoderma lucidum IY009, we obtained the low and high molecular proteoglycan by ultrafiltration and sepharose CL-4B column chromatography. The physicochemical properties of these fractions were as follows. When the proteoglycan separated by ultrafiltration and sepharose CL-4B column chromatography, its was not fractionated completely. The molecular weight of high molecular proteoglycan by the gel column chromatography (CH) was 250 kD and 2,000 kD, and low molecular proteoglycan was 12kD. The total carbohydrate was consisted of 75.7% (UH) and 96.7% (CH), and the low fraction was 72.7% (UL) and 87.1% (CL), respectively. The sugar of high and low molecular proteoglycan composed of glucose, mannose, fructose, galactose, xylose, ribose and arabinose. Glucose contents of all fraction were ranged from $46.9%{\sim}82.4%$ of the total sugar and the ratio of ${\alpha}$\;and\;{\beta}-glucose$ was $0.84{\sim}1.14$, and its indicated the proteoglycan to be ${\beta}-glucan$. Amino acids pattern showed that the fractions contained a large amount of aspartie acid, glutamic acid, alanine and leucine. These fractions showed the characteristics of IR absorption for ${\beta}-glucan$ at $890\;cm^{-1}\;and\;^{13}C-NMR$ spectroscopy showed the presence of the ${\beta}-1,3-glucan$ and a ${\beta}-1,6-glucan$.

• Research in Community and Public Health Nursing
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• v.13 no.1
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• pp.182-196
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• 2002

The purpose of this study was to provide the basic resources for developing a parish nursing program. We did this by investigating what demands were made on the parish nursing service by the parishes or churches under review. The subjects of this study were 96 pastors located throughout the City of Busan. NP (New paragraph) $\gg$ We conducted our research by utilizing a modified version of the study created by Hwang (2000) and by using the help of prior research and professionals gathered from the parish nurse questionnaire by Djupe (1990). The data in this study were collected from July 1 to Oct. 31, 2001, using the questionnaire method. The Data were analyzed by: (a) frequency: (b) percentage: (c) mean: (d) standard deviation, and x^2-test$ with SPSS/PC program. The study has found the follows: 1. For subjects making demands on the parish nursing service, 95.8% were in need of using the services of parish nurses. On the demands of parish nursing service for the subjects, 95.8% the necessity of parish nursing services. And they answered by their intention of asking for parish nursing service practice. 2. Of the subjects under review, 71.9% were part-time workers and 28.1% were full-time employees 71.9% of part time and 28.1% of full times duty. In terms of the method of pay for work, 41.8% were pay free or freelance while 51.2% were on salary. And engagement intention of parish nurse as preacher was 88.5%. 3. The demand for nursing services in various categories were as follows. (a) hospice care: (4.02 1.11), (b) health screening: (3.98 1.09), (c) home visiting: (3.97 1.16), (d) group health education: (3.81 1.12), (e) organization of volunteer groups: (3.75 1.12), (f) individual health education: (3.75 1.14), (g) advice on choosing hospital or hospital consultation: (3.69 1.21) and (h) individual counseling: (3.51 1.31). 4. In terms of the specific services rendered by parish nurses. our study found that services were needed for the following: physical symptom management; preparation before death in spiritual preparation for death, blood pressure check in health examination, home visiting where the patient makes phone call, management of chronic disease in group health education, disease management in individual health education, advice on choosing hospital, or hospital consultation: and physical problems in individual counseling. 5. With respect to whether there was a correlation between what church a pastor came from and the types of demands made, there was NO significant difference found. 6. In relation to the characteristics of the subjects and their church and the hope demands (duty pattern and method of payment and engagement intention of parish nurse as preacher) for parish nurses, these had non significant differences. In conclusion, the perception of parish nursing service is very high. Moreover, we found that there is a great demand for well ordered parish nursing services to promote the health of each congregation. Before doing so, it would be better to make things known and to consider the relevant characteristics shown in the researched results.

• Journal of the Korean earth science society
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• v.21 no.5
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• pp.611-622
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• 2000

To investigate the exchange rates of mercury(Hg) across soil-air boundary, we undertook the measurements of Hg flux using gradient technique from a major waste reclamation site, Nan-Ji-Do. Based on these measurement data, we attempted to provide insights into various aspects of Hg exchange in a strongly polluted soil environment. According to our analysis, the study site turned out to be not only a major emission source area but also a major sink area. When these data were compared on hourly basis over a full day scale, large fluxes of emission and deposition centered on daytime periods relative to nighttime periods. However, when comparison of frequency with which emission or deposition occurs was made, there emerged a very contrasting pattern. While emission was dominant during nighttime periods, deposition was most favored during daytime periods. When similar comparison was made as a function of wind direction, it was noticed that there may be a major Hg source at easterly direction to bring out significant deposition of Hg in the study area. To account for the environmental conditions controlling the vertical direction of Hg exchange, we compared environmental conditions for both the whole data group and those observed from the wind direction of strong deposition events. Results of this analysis indicated that the concentrations of pollutant species varied sensitively enough to reflect the environmental conditions for each direction of exchange. When correlation analysis was applied to our data, results indicated that windspeed and ozone concentrations best reflected changes in the magnitudes of emission/deposition fluxes. The results of factor analysis also indicated the possibility that Hg emission of study area is temperature-driven process, while that of deposition is affected by a mixed effects of various factors including temperature, ozone, and non-methane HCs. If the computed emission rate is extrapolated to the whole study area we estimate that annual emission of Hg from the study area can amount to approximately 6kg.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.15 no.1
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• pp.113-125
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• 2004

Effect of microwave radiation on physico-chemical properties of cor'n starches was studied. Waxy com, com and high amylose com starches of varying moisture content(20～35%) were subjected to microwave processing(2450MHz) at $120^{\circ}$ and the experimental starch samples were examined by a X-ray diffractometry, rapid viscosity analyzer(RVA) and. with the samples in temperature was observed and the peaks of high amylose com starches at $2^{\circ}$=5.0, 15.0 and $23.0^{\circ}$, were disappeared indicating the melting of crystallines while those of com and waxy com had not changed. A change in gelatinization pattern was observed in the case of corn starches from type A with nearly no peak-viscosity and breakdown to type C. Except a decreased viscosity, no change was observed in those of waxy com starches.

• The Journal of the Society of Korean Medicine Diagnostics
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• v.10 no.1
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• pp.109-140
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• 2006

Background: In practicing qigong, People must achieve three Points : adjust their Posture, control their breathing and have a peace of mind. That is, Cho-Sin [調身] , Cho-Sik [調息] , Cho-Sim [調心] . Slow respiration is the important pattern of respiration to improve the human health. However, unsuitable breathing training have been occurred to mental disorder such as insomnia, anorexia etc. So, we think that the breathing training to consider the individual variations are desired. Objectives: We performed this study to examine the physiological effects of controlled respiration on the normal range of frequency domain electroencephalogram(EEC) in healthy subjects Also, to study examine individual variations according to the physiological effects between controlled respiration and Han-Yeol [寒熱] , respiration period, gender and age-related groups on the EEC in healthy subjects. Methods: When the subjects controlled the time of breathing (inspiration and expiration time) consciously, compared with natural respiration, and that their physiological phenomena are measured by EEC. In this research we used breathing time as in a qigong training (The Six-Word Excise) and observed physiological phenomena of the controlled natural respiration period with the ratio of seven to three(longer inspiration) and three to seven(longer expiration) . We determined, heat-cold score by Han-Yeol [寒熱] questionnaire, average of natural respiration period, according to decade, EEC of 140 healthy subjects (14 to 68 years old; 38 males, 102 females) by means of alpha, beta spectral relative power. Results: 1) In Controlled respiration compared with the natural respiration, ${\alpha}\;I\;(Fp2)\;and\;{\beta}$ I (Fpl, Fp2, F3, F4) decreased on the EEC. 2) In controlled respiration compared with the natural respiration, ${\beta}$ I (Fpl, Fp2, F3, F4) increased with cold group, ${\alpha}/{\beta}$(F3) decreased with heat group, ${\alpha}$ I (Fp2)increased with cold group in longer inspiration. But by means of compound effects, ${\alpha}$ II(F3) increased with cold group in longer inspiration, the other side ${\alpha}$ I (F3) decreased with heat group in controlled respiration on the EEC. 3) In controlled respiration compared with the natural respiration, ${\alpha}$ I (Fp2) decreased with decreased-respiratory-rate(D.R.R.) group, ${\beta}$ I (Fpl, Fp2, F3, F4) increased with D.R.R. and D.R.R. groups, ${\alpha}/{\beta}$(F3) decreased with D.R.R. group. But by means of compound effects, in controlled respiration compared with the natural respiration, ${\alpha}/{\beta}$(F3) decreased with D.R.R. group on the EEG. 4) In controlled respiration compared with the natural respiration, ${\beta}$ I (Fpl, F3, F4) increased with female cup, ${\beta}$ I (Fp2) increased with male and female groups, ${\alpha}/{\beta}$(F3) decreased with male group. But by means of compound effects, in controlled respiration compared with the natural respiration, ${\alpha}$ I (Fp2) increased with female group on the EEC. 5) Compared with the natural respiration, in longer expiration ${\alpha}$ I (Fp2) increased in their forties group, in longer inspiration ${\alpha}$ I (Fp2) increased in their fifties group. But by means of compound effects, in controlled respiration compared with the natural respiration, ${\beta}$ I (Fpl) decreased in teens group on the EEG.

• Journal of the Korea Organic Resources Recycling Association
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• v.24 no.4
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• pp.77-83
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• 2016

The objectives of this study was to investigate the difference between organic-farming and conventional-farming soils relatives to soil chemical properties and microbial flora. Fifteen soil sampling sites were chosen from the certified organic upland farm, considered with its location, crop and application of organic compost types. Soil chemical properties were analyzed by standard methods established by National Institute of Agricultural Sciences, Rural Development Administration. For the soil chemical properties, the values of pH were ranged from 4.5 to 7.3. The values of electrical conductivity (EC) in the sampling sites were below 2 dS/m of convention cultivation soil. For analyzing the microbial flora, the bacillus(16S rDNA) and cladothricosis(18S rDNA) were analyzed by using PCR-DGGE (Denaturing Gradient Gel Electrophoresis) in the soil of 15 sampling sites. Cluster analysis of biodiversity index was performed by using pattern of DGGE. DGGE patterns and clustering analysis of bacterial DNA from soil extracts revealed that the bacterial community was differentiated between less than 5 years and more than 5 years depending on the cultivation history. But there was no consistent tendency between cultivation history and regional trend in the case of molds. Therefore, it would be very effective to analyze bacterial clusters of organically cultivated soils in long - term cultivated soil for more than 5 years.

• Journal of Nutrition and Health
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• v.31 no.5
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• pp.897-905
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• 1998

Docosahexaenoic acid(DHA), a $\omega$3 series fatty acid and arachidonic acid(AA). a $\omega$6 series fatty acid were found in relatively high concentrations in the phospholipids(PLs) of cell membranes of nerve tissues, and they can be affected by various factors. The present study examined the effects of dietary $\omega$6 and $\omega$3 fatty acid composition on P/M/S and on $\omega$3/$\omega$6 fatty acid ratios in brain PLs of 2nd generation rats. The expeimental diets consisted of 10% fat(by wt), which were computer- searched mixed oil('M') with P/M/S ratio, 1 : 1.4 : 1 and $\omega$6/$\omega$3 ratio, 6 : 1 and safflower oil('S') poor in $\omega$3 fatty acids. The experimental diets were started 3-4 wks prior to conception. During the lactation period, the feeding mothers were switched 1 wk after birth and provided the pups for 2 wks with milk which had compositions different from that of their natural mother. The same diet as their mothers was provided from weaning to 9 wks of age. The 'M'and 'S' rats were again subdivided into MM, MS, SS, SM rats according to diet which their lactating mothers were fed from the begining of the experiment. The relative percentage of P/M/S fatty acids in brain PLs in all experimental groups converged to a very similar value at 9 wks of age, indicating the existence of a control mechanism for the degree of fatty acids, unsaturation. The $\omega$3/$\omega$6 fatty acid ratios of brain PLs converged to about 1.0 in MM & SM groups and to 0.7 in SS & MS groups, suggesting also the existence of some balance between $\omega$3 and $\omega$6 fatty acids in developing rat brain. The concentrations of $\omega$3 fatty acids, especially DHA, in the SM group were increased and became similar to those in MM group at 9 wks of age. The increase in DHA of brain PLs was counterbalanced b)r a decrease in 22 5$\omega$6. Therefore, the ratios of 22 : 6$\omega$6/22 : 5$\omega$6 were higher in both MM & SM groups than those of SS & MS groups at 9 wak of age. Although dietary $\omega$3 and $\omega$6 fatty acids affected 22 : 6$\omega$S and 22 : 5$\omega$6 contained in rat brain PLs reciprocally, the relative percentage of AA did not appear to be significantly influenced by the diet in all groups at 9 wks of age, suggesting that a mechanism for the maintenance of a certain level of AA in brain PLs exists. In conclusion, the $\omega$3/$\omega$6 fatty acid and 22 : 6$\omega$3/22 : 5$\omega$6 ratios, but not P/M/S ratio, of rat brain PLs were affected by the postnatal dietary changes. Futher studies are required to clarify the mechanism(S) of ensuring a certain level of DHA and of maintaining a similar level of AA in rat brain PLs after. weaning(9 wk) regardless of prenatal and postnatal dietary changes. (Korean J Nutrition 31(5) : 897-905, 1998)

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.488-496
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• 2017

Emissions of pollutants from ship-based sources are controlled by the International Maritime Organization (IMO). Since pollutants emitted from ship may be dispersed to the land, controlling emissions from ships is necessary for efficient air quality management in Incheon, where exposure to ship-based pollution is frequent. It has been noted that the ratios of air pollutant emissions from coastal areas to inland areas are about 14% for NOx and 10% for SOx. The air quality of coastal urban areas is influenced by the number of ships present and the dispersion pattern of the pollutants released depending on the local circulation system. In this study, the dispersion of pollutants from ship-based sources was analyzed using the numerical California Puff Model (CALPUFF) based on a meteorological field established using the Weather Research and Forecasting Model (WRF). Air pollutant dispersion modeling around coastal urban regions such as Incheon should consider point and line sources emitted from both anchored and running ships, respectively. The total average NOx emissions from 82-84 ships were 6.2 g/s and 6.8 g/s, entering and leaving, respectively. The total average SOx emissions from 82-84 ships, entering and leaving, were 3.6 g/s and 5.1 g/s, respectively. The total average emissions for NOx and SOx from anchored ships were 0.77 g/s and 1.93 g/s, respectively. Due to the influence of breezes from over land, the transport of pollutants from Incheon Port to inland areas was suppressed, and the concentration of NOx and SOx inland were temporarily reduced. NOx and SOx were diffused inland by the sea breeze, and the concentration of NOx and SOx gradually increased inland. The concentration of pollutants in the area adjacent to Incheon Port was more influenced by anchored ship in the port than sea breezes. We expect this study to be useful for setting emission standards and devising air quality policies in coastal urban regions.