• Asia pacific journal of information systems
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• v.17 no.2
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• pp.123-137
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• 2007

The advent of the Internet and related Web technologies has created an easily accessible link between a firm and its customers, and has provided opportunities to a firm to use information technology to support supplementary after-sale services associated with a product or service. It has been widely recognized that supplementary services are an important source of customer value and of competitive advantage as the characteristics of the product itself. Many of these supplementary services are information-based and need not be co-located with the product, so more and more companies are delivering these services electronically. Net-based customer service, which is defined as an Internet-based computerized information system that delivers services to a customer, therefore, is the core infrastructure for supplementary service provision. The importance of net-based customer service in delivering supplementary after-sale services associated with product has been well documented. The strategic advantages of well-implemented net-based customer service are enhanced customer loyalty and higher lock-in of customers, and a resulting reduction in competition and the consequent increase in profits. However, not all customers utilize such net-based customer service. The digital divide is the phenomenon in our society that captures the observation that not all customers have equal access to computers. Socioeconomic factors such as race, gender, and education level are strongly related to Internet accessibility and ability to use. This is due to the differences in the ability to bear the cost of a computer, and the differences in self-efficacy in the use of a technology, among other reasons. This concept, applied to e-commerce, has been called the "e-commerce divide." High Internet penetration is not eradicating the digital divide and e-commerce divide as one would hope. Besides, to accommodate personalized support, a customer must often provide personal information to the firm. This personal information includes not only name and address, but also preferences information and perhaps valuation information. However, many recent studies show that consumers may not be willing to share information about themselves due to concerns about privacy online. Due to the e-commerce divide, and due to privacy and security concerns of the customer for sharing personal information with firms, limited numbers of customers adopt net-based customer service. The limited level of customer adoption of net-based customer service affects the firm profits and the customers' welfare. We use a game-theoretic model in which we model the net-based customer service system as a mechanism to enhance customers' loyalty. We model a market entry scenario where a firm (the incumbent) uses the net-based customer service system in inducing loyalty in its customer base. The firm sells one product through the traditional retailing channels and at a price set for these channels. Another firm (the entrant) enters the market, and having observed the price of the incumbent firm (and after deducing the loyalty levels in the customer base), chooses its price. The profits of the firms and the surplus of the two customers segments (the segment that utilizes net-based customer service and the segment that does not) are analyzed in the Stackelberg leader-follower model of competition between the firms. We find that an increase in adoption of net-based customer service by the customer base is not always desirable for firms. With low effectiveness in enhancing customer loyalty, firms prefer a high level of customer adoption of net-based customer service, because an increase in adoption rate decreases competition and increases profits. A firm in an industry where net-based customer service is highly effective loyalty mechanism, on the other hand, prefers a low level of adoption by customers.

• Asia pacific journal of information systems
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• v.18 no.1
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• pp.25-51
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• 2008

Researchers have been continuously interested in the adoption of information technology (IT) since it is of great importance to the information systems success and it is also an important stage to the success. Adoption alone, however, does not ensure information systems success because it does not necessarily lead to achieving organizational or individual objectives. When an organization or an individual decide to adopt certain information technologies, they have objectives to accomplish by using those technologies. Adoption itself is not the ultimate goal. The period after adoption is when users continue to use IT and intended objectives can be accomplished. Therefore, continued IT use in the post-adoption period accounts more for the accomplishment of the objectives and thus information systems success. Previous studies also suggest that continued IT use in the post-adoption period is one of the important factors to improve long-term productivity. Despite the importance there are few empirical studies focusing on the user behavior of continued IT use in the post-adoption period. User behavior in the post-adoption period is different from that in the pre-adoption period. According to the technology acceptance model, which explains well about the IT adoption, users decide to adopt IT assessing the usefulness and the ease of use. After adoption, users are exposed to new experiences and they shape new beliefs different from the thoughts they had before. Users come to make decisions based on their experiences of IT use whether they will continue to use it or not. Most theories about the user behaviors in the pre-adoption period are limited in describing them after adoption since they do not consider user's experiences of using the adopted IT and the beliefs formed by those experiences. Therefore, in this study, we explore user's experiences and beliefs in the post-adoption period and examine how they affect user's intention to continue to use IT. Through deep literature reviews on the construction of subjective beliefs by experiences, we draw three meaningful constructs which theoretically have great impacts on the continued use of IT: perceived habit, confirmation, and computer self-efficacy. Then, we examine the role of the subjective beliefs on the cognitive/affective attitudes and intention to continue to use that IT. We set up a research model and conducted survey research. Since IT use implies interactions among a user, IT, and a task, we carefully selected the sample of users using same/similar IT to perform same/similar tasks, to exclude unwanted influences of other factors than subjective beliefs on the IT use. We also considered that the sample of users were able to make decisions to continue to use IT volitionally or at least quasi-volitionally. For each construct, we used measurement items recognized for reliability and widely used in the previous research. We slightly modified some items proper to the research context and a pilot test was carried out for forty users of a portal service in a university. We performed a full-scale survey after verifying the reliability of the measurement. The results show that the intention to continue to use IT is strongly influenced by cognitive/affective attitudes, perceived habits, and computer self-efficacy. Confirmation affects the intention to continue indirectly through cognitive/affective attitudes. All the constructs representing the subjective beliefs built by the experiences of IT use have direct and/or indirect impacts on the intention of users. The results also show that the attitudes in the post-adoption period are formed, at least partly, by the experiences of IT use and newly shaped beliefs after adoption. The findings suggest that subjective beliefs built by the experiences have deep impacts on the continued use. The results of the study signify that while experiencing IT in the post-adoption period users form new beliefs, attitudes, and intentions which may be different from those of the pre-adoption period. The results of this study partly demonstrate that the beliefs shaped by the behaviors, those are the experiences of IT use, influence users' attitudes and intention. The results also suggest that behaviors (experiences) also change attitudes while attitudes shape behaviors. If we combine the findings of this study with the results of the previous research on IT adoption, we can propose a cycle of IT adoption and use where behavior shapes attitude, the attitude forms new behavior, and that behavior shapes new attitude. Different from the previous research, the study focused on the user experience after IT adoption and empirically demonstrated the strong influence of the subjective beliefs formed in the post-adoption period on the continued use. This partly confirms the differences between attitudes in the pre-adoption and in the post-adoption period. Users continuously change their attitudes and intentions while experiencing (using) IT. Therefore, to make users adopt IT and to make them use IT after adoption is a different problem. To encourage users to use IT after adoption, experiential variables such as perceived habit, confirmation, and computer self-efficacy should be managed properly.

• The Korean Journal of Nuclear Medicine
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• v.38 no.4
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• pp.306-310
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• 2004

Purpose: The aim was to assess how the background site affects the Gates' glomerular filtration rate(GFR) measurement using Tc-99m-DTPA in correlation with GFR by I-125-lothalamate method. Material and methods: The study populations were 63 adults with 39 men and 24 women aged from 20 to 59 yrs (mean=37.9 yrs). The fellowing five background regions of interest were used in measurement of GFR using Gates' method: 1) lower side of each kidney(subrenal), 2) around each kidney(circumferential), 3) upper side of each kidney(suprarenal), 4) lateral side of each kidney(lateral), 5) between the two kidneys(inter-renal). We also measured GFR using I-125-iothalamate in each subject. The two studies were separated by 1 to 3 weeks. The subjects were divided into two groups by renal depth. Group 1 with renal $depth{\geq}7cm$ and group 2 with renal depth<7cm. We calculated the means and standard deviations of the GFRs measured by two studies. And we statistically analyzed the correlation and differences among GFRs by Gates' method and the GFR by iothalamate method with correlation analysis. Results: The GFRs by Gates' method using suprarenal and inter-renal background correction showed better correlation with the GFR measured by I-125-iothalamate. And GFRs measured by Gates' method showed statistically significant correlation with the GFR measured by I-125-iothalamate in the group with renal depth<7cm. But GFRs measured by Gates' method did not show statistically significant correlation with the GFR measured by I-125-iothalamate in the group with renal $depth{\geq}7cm$. Conclusion: GFRs measured with Gates' method showed higher correlation with the GFR measured by I-125-iothalamate when the regions of interest were plated over the suprarenal and inter-renal backgrounds. And GFRs measured with Gates method showed statistically significant correlation with the GFR measured by I-125-iothalamate in the group with renal depth<7cm.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.45-50
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• 2011

Purpose: It appears the different value when the injection dose is calculating for patients on each PET/CT systems. It directly affects the technologists' radiation exposed dose. We studied the effect of the variable injection doses from several PET/CT systems to exposure dose for technologists. Materials and Methods: Six technologists have worked for 5 months through unit rotations with 3 PET/CT systems {Scanner 1 (S1): 0.15 mCi/kg, Scanner 2 (S2): 0.17 mCi/kg, Scanner 3 (S3): 0.12 mCi/kg}. Eighteen to 19 patients have had examinations per a day on each PET/CT systems. Examination parameters were adjusted to the same. TLDs were used for checking the exposure dose of technologists. Results: Each technologists' the monthly average exposure dose was as follows; S1: 0.76 mSv, S2: 0.93 mSv, S3: 0.47 mSv. The maximum exposure dose was 1.12 mSv, and minimum was 0.42 mSv. The results showed significance in the correlation between the PET/CT system and the exposure dose (p<0.005). Conclusion: When the amount of injection dose was small, the exposure dose was decreased not only the patients but also the technologists. The exposure dose was decreased by the individual proficiency of technologists. However, the low injection dose can highly reduce the exposure dose for technologist so that there will be needed to following studies.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.229-237
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• 2015

This study aims to offer basic data to effectively preserve and manage pine forests using more precise pine forests' distribution status. In this regard, this study predicts the geographical distribution change of pine forests growing in South Korea, due to climate change, and evaluates the spatial distribution characteristics of pine forests by age. To this end, this study predicts the potential distribution change of pine forests by applying the MaxEnt model useful for species distribution change to the present and future climate change scenarios, and analyzes the effects of bioclimatic variables on the distribution area and change by age. Concerning the potential distribution regions of pine forests, the pine forests, aged 10 to 30 years in South Korea, relatively decreased more. As the area of the region suitable for pine forest by age was bigger, the decreased regions tend to become bigger, and the expanded regions tend to become smaller. Such phenomena is conjectured to be derived from changing of the interaction of pine forests by age from mutual promotional relations to competitive relations in the similar climate environment, while the regions suitable for pine forests' growth are mostly overlap regions. This study has found that precipitation affects more on the distribution of pine forests, compared to temperature change, and that pine trees' geographical distribution change is more affected by climate's extremities including precipitation of driest season and temperature of the coldest season than average climate characteristics. Especially, the effects of precipitation during the driest season on the distribution change of pine forests are irrelevant of pine forest's age class. Such results are expected to result in a reduction of the pine forest as the regions with the increase of moisture deficiency, where climate environment influencing growth and physiological responses related with drought is shaped, gradually increase according to future temperature rise. The findings in this study can be applied as a useful method for the prediction of geographical change according to climate change by using various biological resources information already accumulated. In addition, those findings are expected to be utilized as basic data for the establishment of climate change adaptation policies related to forest vegetation preservation in the natural ecosystem field.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.381-402
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• 2017

In order to investigate distribution of vascular plants along elevational gradient in the Nodong valley of Gyebangsan, vascular plants of eight sections with 100-meter-high were surveyed from the Auto-camping site (800 m) to the top of a mountain (1,577 m). There were a total of 382 taxa: 89 families, 234 genera, 339 species, 7 subspecies, 34 varieties, and 2 forms. As a result of analyzing the pattern of species richness, it showed a reversed hump-shaped with minimum richness at mid-high elevation. As a result of analyzing habitat affinity types, the proportion of forest species increased with increasing elevation. But, the ruderal species decreased with increasing elevation, and then increased at the top of a mountain. As for the proportion of life forms, the annual herbs gradually decreased with increasing elevation, but it did not appear between 1,300 m and 1,500 m and then increased at the top of a mountain. The trees gradually increased with elevation and decreased from 1,300~1,400 m. The vascular plants divided into four groups by using DCA. The arrangement of each stands was arranged in order from right to left on the I axis according to the elevation. The distribution of vascular plants is determined by their own optimal ranges of vegetation. Also, rise in temperature due to climate change affects the distribution of vascular plants, composition, and diversity. Therefore, continuous monitoring is necessary to confirm ecological and environmental characteristics of vegetation, distribution ranges, changes of habitat. Furthermore, plans for conservation and management based on these data should be prepared according to climate change.

• Journal of the Korean Society for Library and Information Science
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• v.46 no.4
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• pp.285-309
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• 2012

The purpose of this study is to analyze whether bibliographic factors influence citation speed and the number of citations or not and whether citation speed affects the number of citations. Another purpose of this study is that if bibliographic factors carry out a significant role. For this analysis, this study is based on the assumption that all papers published by researchers in South Korea distributed power law shape. The main results of this study are as follows: First, the papers written by foreign first authors or reprint authors were cited more quickly from first citation speed and average citation speed. These papers were cited much more from first citation speed and average citation speed than by domestic first authors or reprint authors. The papers, collaborated by international researchers, were cited more quickly from first citation speed but were not different from average citation speed than by only domestic researchers. The papers, collaborated by international researchers, were cited much more than by only domestic stand-alone researchers. The number of authors and the impact factor influenced first citation speed, average citation speed and the number of citations. Second, the faster first citation speed and the slower average citation speed, the more papers were cited. First citation speed more affected the higher number of citations than the average citation speed. Third, all five bibliographic factors influenced the impact relationship from first citation speed to the number of citations through the moderating effect analysis. Fourth, only three bibliographic factors (the country of the first author; the country of the reprint author; the number of the coauthors) affected the impact relationship from first citation speed to the number of citations but two bibliographic factors did not influence through the moderating effect analysis.

• Korean journal of food and cookery science
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• v.31 no.4
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• pp.387-394
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• 2015

The red snow crab lives at a depth 200-2,000 m in the east coast. It has a smooth taste with a rich texture. However mostly red snow crab are only utilized materials. For seafood development, research is needed on using red snow crab in various products. In this study, quality changes in fried rice prepared with red snow crab meat, red snow crab emulsion sauce and red snow crab effluent were investigated. Physicochemical, microbiological and sensory characteristics were determined during storage at -20, 4 and $25^{\circ}C$ for 5 weeks to assess changes in the quality of the fried rice. The pH and acidity values did not show any significant differences at $-20^{\circ}C$. The VBN and TBA values of fried rice stored at 4 and $25^{\circ}C$ were significantly higher than those of fried rice stored at $-20^{\circ}C$ during the same storage period. The viable cell count of the fried rice stored at $-20^{\circ}C$ changed little during the storage period. During storage at $25^{\circ}C$, the overall quality was initially 8.0, but rapidly decreased to 1.0 after 5 weeks. In conclusion, the best storage temperature for both quality and safety was $-20^{\circ}C$. The storage condition for instant rice containing red snow crab affects the quality and we confirmed the applicability of using materials from red snow crab.

• The Korean Journal of Mycology
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• v.40 no.1
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• pp.19-38
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• 2012

This study was conducted to investigate the diversity of higher fungi and relationship between higher fungi and climatic factors in Naejangsan National Park from April 2004 to October 2010. The obtained results from investigation were as follows. The higher fungi were classified into 48 families, 158 genera and 451 species in Basidiomycotina, 13 families, 26 genera and 39 species in Ascomycotina, and 4 families, 7 genera and 7 species in Myxomycetes, and most of them belonged to Hymenomycetidae in Basidiomycotina. Dominant species belonged to Ttricholomataceae (72 species), Russulaceae (39 species), Polyporaceae (41 species), Boletaceae (40 species), Cortinariaceae (35 species) and Amamtaceae (28 species). For the habitat environment, the ectomycorrhizal mushrooms were 38.8% (15 families, 36 genera and 193 species), litter decomposing and wood rotting fungi 39.4% (36 families, 107 genera and 196 species), grounding Fungi 19.9% (24 families, 51 genera and 99 species) and others 1.8% (3 families, 4 genera and 9 species). Monthly, most of higher fungi were found in July, August and September, and least found in November. In climatic conditions, most higher fungi were occurred in $23^{\circ}C$and above of mean temperature, $20^{\circ}C$and above of minimum temperature, and $29^{\circ}C$and above of maximum temperature. most of higher fungi were found in 73% and above of relative humidity and 200 mm and above of monthly precipitation. In case of ectomycorrhizal fungi like Amamtaceae, Boletaceae and Cortinariaceae, significance levels are not high in $32^{\circ}C$ and above of maximum temperature which mostly affects species occurrence than other climatic factors of mean and minimum temperature and monthly precipitation.

• Korean Journal of Poultry Science
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• v.18 no.2
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• pp.85-95
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• 1991

The investigation concerned an effect of the ground charcoal powder and organic acids on the digestibilities of protein and energy or the contents of uric acid, ammonia, creatine and urea in excreta of 113 week-old White Leghorn strain layers. Birds were fed basal (control) diet composed of mainly corn-soybean meal during a week of previous feeding and subsequent experimental diets during 12 weeks of experimental feeding . The experimental diets were the control diet(CON). diet(CPD) substituted 0.5% of the ground charcoal powder with the defatted rice bran of the CON, diet(PWV) added 0.1mM(based on the acetic acid) wood vinegar in the CPD and diet(PFA) added 0.1mM (based on the acetic acid) fermented acetic acid in the CPD. Birds fed CPD excreted significantly(P＜0.05) more fecal nitrogen(FN) and lower urinary nitrogen (UN) than those of birds fed CON. Digestibility of protein was lower significantly (P＜ 0.05) in CPB-fed bird than in bird fed CON. while birds fed CON. PWV and PFA showed similar values. Also urinary nitrogen per nitrogen intake (UN/NI) or absorbed nitrogen (UN/AN) was significantly (P＜0.05) lower in birds fed CPD compared with those in birds fed CON. And birds fed PWV tended to increase UN/NI and UN/AN, while PFA-fed birds excreted significantly (P＜0.05) higher UN/Nl and UN/Ah than those of birds fed CPD diet. The uric acid nitrogen (UAN) per nitrogen intake (UAN/NI) or absorbed nitrogen (UAN/AN) were lower significantly(P＜0.05) in CPD-fed birds and were tended to decrease in birds fed PWV compared with those in birds fed CON and PFA The ammoniacal nitrogen(AMN) per nitrogen intake (AMN/NI) or absorbed nitrogen (AMN/NI) was tended to increase in birds fed experimental diets and was increased significantly(P＜0.05) in birds fed PFA compared with those of birds fed CON. The excretion of creatine and urea nitrogen per nitrogen intake or absorbed nitrogen was shown similar values among birds fed experimental diets Digestibility of energy (DE/GE) was not shown any significant effect of experimental diet and were in the range of 80~84%. But metabolizability (ME/GE or MEn/GE) was increased in birds fed CPD and PWV and was decreased in birds fed PFA compared with those in birds fed CON. Although birds fed PWV showed significantly(P＜0.05) higher ME/GE than bird fed PFA, the MEn/GE were higher significantly (P＜0.05) in birds fed CON and CPD compared with that in birds fed PFA. Fecal energy affects 10~23% in the change of metabolizability though significant effect of fecal energy on the metabolizability were not found. But the effect of urinary energy on the metabolizability of diet was lowered as 2.3~3, 0% and the effect of experimental diets on the metabolizability of diets was due to change of urinary energy which also was originated from the change of uric acid energy.