• Korean Journal of Environmental Agriculture
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• v.34 no.3
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• pp.161-167
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• 2015

BACKGROUND: For the heavy metal cotamination sites, it is very important to estimate the human bioavailability quotients for heavy metals in paddy soils released from mine tailings, which is a major source of contamination in Korea, and to assess the human health risks of heavy metals. METHODS AND RESULTS: This experiment was carried out to investigate the human bioavailability quotient of the heavy metals in paddy soils below part of the closed metalliferous mine. For estimating the human bioavailability quotients for heavy metals, 30 paddy soils below part of the closed mine were collected, and analyzed for Cd, Cu, Pb, Zn, and As using simple bioavailability extraction test(SBET). The quantities of Cd, Cu, Pb, Zn and As extracted from paddy soils below part of the mine by using the SBET analysis were 28.1, 17.3, 34.1, 14.6 and 2.3% respectively. Specially, the maximum values of Cd, Pb and Zn were 73.3, 81.5 and 58.1% of human bioavailability quotient, respectively, and varied considerably among the sampling sites. The human bioavailability quotient of Cd, Cu, Pb and Zn in soils near the closed mine showed significant positive correlation among soil pH value, O.M. and Ex. Ca. contents, while it correlated negatively between soil Ex. K and Ex. Mg contents in paddy soils. Also, its of Cd, Cu, Pb and Zn in paddy soils showed significant positive correlation with 0.1M HCl extractable and total contents, while in soils, it correlated negatively with As content in soil near the closed mine. CONCLUSION: The results of the simple bioavailability extraction test (SBET) indicate that regular ingestion of soils by the local population could be closed a potential health threat due to long-term heavy metals exposure in these mine areas.

• Journal of Venture Innovation
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• v.3 no.2
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• pp.1-21
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• 2020

Recently, the emergence of new technologies caused by the Fourth Industrial Revolution caused a great change not only in the overall society but also in the retail industry. In the retail industry, unmanned stores based on new technologies have emerged, changing the consumption behavior of consumers. In particular, the global pandemic caused by COVID-19, which appeared in December 2019, raised social risks, and as a result of this, the beginning of the non-face-to-face era, interest in unmanned stores is increasing. In this study, the effects of benefits factors (perceived usefulness, perceived economics, perceived enjoyment, relative advantages) and sacrifice factors (perceived risk, technicality) perceived by unmanned store users on continuous use intention through perceived value. In addition, it is a study to test through empirical analysis what role the social risk from COVID-19 plays in the process of consumption through unmanned stores. The purpose of this study is to provide strategic implications for the activation of unmanned stores in the non-face-to-face era. In this study, a total of 293 copies of data were collected for users of unmanned stores for hypothesis testing. In addition, the collected data was analyzed using SPSS 21.0 and AMOS 21.0 statistical programs. The results of the study are summarized as follows. First, it was found that the perceived benefits (perceived usefulness, perceived economics, perceived playfulness, and relative advantages) of unmanned stores all had a significant positive effect on perceived value. Second, it was found that all perceived sacrifices (perceived risk, technicality) of unmanned stores had a significant negative effect on perceived value. Third, it was found that the perceived value of unmanned stores had a significant positive effect on the intention to continue use. Finally, the social risk from COVID-19 has been shown to play a moderating role when the perceived sacrifice of unmanned stores affects the perceived value.

• Asia pacific journal of information systems
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• v.20 no.4
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• pp.53-79
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• 2010

The study was originated from recognition that project participants' satisfaction should be Improved to raise project performance and to make progress of a successful project since the above dissatisfaction was operated as a danger factor of the project. The study selected one large-scale sample project and attempted measuring characteristics of the project, participants' satisfaction and project performance with the whole project participants. The study analyzed correlations between individual level (team members) and group level (development team), and examined what effect a sub project manager under complicated hierarchical organization of the large-scale project, namely PL (project leader)'s leadership style had on each individual project participant's satisfaction and what effect project uncertainty in organization/technology environment had on project participants' satisfaction and project performance. The study verified that development team (group) had an effect on team member (individual)-level project participants' satisfaction by disclosing that there was a significant dispersion among groups within project participants' satisfaction by each individual. It is analyzed that it is necessary to make improvement through approach by each pertinent team to raise individual-level project participants' satisfaction. The study also verified PL's ideal leadership under strict methodology and hierarchical control of the large-scale project. Based on the verification of the hypotheses, the results of the analysis were produced as follows. First, the development team affects the satisfaction level that an individual has when he/she participates in a project. This suggests that the satisfaction with project participation should be improved at the team level. In addition, the project management style and leadership orientation of the manager of a sub project who is mostly affected by the team proved to have a direct influence on the satisfaction with project participation and project performances. Second, both the performance-oriented leadership and the relationship-oriented leadership of the PL of the development team were verified to have a significant effect on the satisfaction of the team members associated with project participation. In other words, when the team members recognize that the PL of the development team shows both the performance-oriented leadership and the relationship-oriented leadership, their satisfaction with project participation increases accordingly. Third, it was verified that the uncertainty of the organizational environment significantly affects the satisfaction level when the PL of the development team exerts a relationship-oriented and performance-oriented leadership. The higher the uncertainty of the organizational environment is, the more the satisfaction with project participation decreases whereas the relationship-oriented leadership has a more positive effect on the satisfaction than the performance-oriented leadership style. Fourth, when the PL of the development team exerts the relationship-related and performance-related leadership, the uncertainty of the technological environment has a significant influence on the satisfaction level. The higher the uncertainty of the technological environment is, the more the satisfaction with project participation decreases whereas the performance-oriented leadership has a more positive effect on the satisfaction than the relationship-oriented leadership style. The result of the research on the uncertainty of the project environment suggests that when the development team leader exerts a relationship-oriented and performance-oriented leadership style, the uncertainty of the organizational environment has a significant effect on the satisfaction with project participation; the higher the uncertainty of the organizational environment, the more the satisfaction level decreases, and the relationship-oriented leadership style affects the satisfaction level more positively than the performance-oriented leadership style. In addition, when the development team leader displays a relationship-oriented and performance-oriented leadership style, the uncertainty of the technological environment has a significant effect on the satisfaction with project participation; the higher the uncertainty of the technological environment. the more the satisfaction level decreases. The performance-oriented leadership style as well affects the satisfaction level more positively than the relationship-oriented leadership style. Based on the above results, the research provides the following implications when handling multiple concurrent projects. First, the satisfaction with the participation in the multiple concurrent projects needs to be enhanced at the team (group) level. Second. the manager of the project team, particularly the middle managers should have both a performance-oriented and relationship (task and human)-oriented attitude and exert a consolidated leadership in order to improve the satisfaction of team members with project participation and their performances. Third, as the uncertainty factor of the technological and organizational environment among the characteristics factors of the project has room for methodological improvement depending on one's effort even though there are some complications, we need to continuously prevent and control the risks resulting from the uncertainties of the technological and organizational environment of the project in order to enhance the satisfaction of project participation and project performances. Fourth, the performance (task)-oriented leadership is required when there is uncertainty in a technological environment while the relationship (human)-oriented leadership is required when there is uncertainty in an organizational environment. This research has the following limitations. First, this research intended to select one large-sized sample project and measure the project characteristics, the satisfaction of all the participants associated with project participation, and their performances. Therefore, it is inappropriate to generalize and apply the result of this result onto other numerous projects. Second, as this case study entailed a survey to measure the characteristics factors and performance of the project, since the result value was based on the perception of project team members, the data may have insufficient objectivity. Third, though this research targeted on all the project participants, some development teams did not provide sufficient data and questionnaires were collected from some specific development teams among the 23 development teams, causing a significant deviation in the response rate among the development teams. Therefore, we need to continuously conduct the follow-up researches making comparisons among the multiple projects, and centering on the characteristics factors of the project and its satisfaction level.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7509-7515
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• 2013

To assess the risk of cancers associated with sleep duration using meta-analysis of published cohort studies, we performed a comprehensive search using PubMed, Embase and Web of Science through October 2013. We combined hazard ratios (HRs) from individual studies using meta-analysis approaches. A random effect dose-response analysis was used to evaluate the relationship between sleep duration and cancer risk. Subgroup analyses and sensitivity analyses were also performed. Publication bias was evaluated using Funnel plots and Begg's test. A total of 13 cohorts from 12 studies were included in this meta-analysis, which included 723, 337 participants with 15, 156 reported cancer outcomes during a follow-up period ranging from 7.5 to 22 years. The pooled adjusted HRs were 1.06 (95% CI: 0.92, 1.23; P for heterogeneity =0.003) for short sleep duration, 0.91 (95% CI: 0.78, 1.07; P for heterogeneity <0.0001) for long sleep duration. In subgroup analyses stratified by cancer type, long duration of sleep showed an inverse relation with hormone-related cancer (HR=0.79; 95% CI: 0.65, 0.97; P for heterogeneity =0.009) and a greater risk of colorectal cancer (HR=1.29; 95% CI: 1.09, 1.52; P for heterogeneity =0.346). Further meta-analysis on dose-response relationships showed that the relative risks of cancer were 1.00 (95% CI: 0.99, 1.01; P for linear trend=0.9151) for one hour of sleep increment per day, and 1.00 (95% CI: 0.98, 1.01; P for linear trend=0.7749) for one hour of sleep increment per night. No significant dose-response relationship between sleep duration and cancer was found on non-linearity testing (P=0.5053). Our meta-analysis suggests a positive association between long sleep duration and colorectal cancer, and an inverse association with incidence of hormone related cancers like those in the breast. Studies with larger sample size, longer follow-up times, more cancer types and detailed measure of sleep duration are warranted to confirm these results.

• Journal of Applied Tourism Food and Beverage Management and Research
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• v.13 no.2
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• pp.45-69
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• 2002

This study is designed to examine feasibility and limitation of outsourcing in cooking Western food in a hotel, to interpret importance of outsourcing(eg. outside order, outside procurement, outside supply) in a broad sense in order to reinforce the core capacity in the cooking department, and to know whether the cooking human power is efficiently used and how much the chefs recognize outsourcing of food materials. As many companies conduct restructuring to cut down its size, the reduction of human power led the Western food cooking in the hotel to lower core capacities, lower quality, and lower efficiency. In addition, the sagging morale of chefs undermined creativity. To change from the traditional kitchen to an economic kitchen needs to look into importance of outsourcing, cognitive attitude of chefs, relation with outside suppliers. Here suggests performance of positive changes in the structure The study examined feasibility and limitation of outsourcing in the hotel kitchen as well as chefs' cognitive attitude toward outsourcing of food materials to reinforce core capabilities of the hotel kitchen. 1. Companies of outsourcing are selected according to variability of price conditions, flexibility of contract conditions, popularity of the outsourcing company, and reputation of the outsourcing company. 2. The importance of outsourcing in the Western food cooking is divided into 4 factors such as standard of selecting outsourcing companies, policies of cooking manu, quality of cooking, and quantity of cooking. 3. The most feasible section in outsourcing of food materials is a process of kneading flour for bread, which shows that many Western-food chefs expect to put higher possibility of outsourcing on the kneading. In other words, when it comes to confectionery and bakery, there are many outside expert processing companies supplying high quality products. In the order of outsourcing feasibility, sauce is followed by processed vegetable, garnish of main dish, and soup. The least feasible section in outsourcing of food materials is appetize. Appetize includes a concept of a improvised dish and needs speed. Due to its color, freshness, and sensibility of taste, the appetize plays a key role in the Western food cooking. 4. When outsourcing is taken in place, the highest risk is to lower the inner cooking skills. Therefore chefs in charge of the Western food sequently recognize both internal problems including storage of cooking skills, unstability of layoffs, and loss of cooperation between departments, and external problems including inferior goods, difficulty of differentiating manu, delay of delivery, and expiration date. It shows that most of the Western food chefs consider risks of the internal problems at first. 5. A effective outsourcing needs appropriate selection of outsourcing companies, maintenance of credibility, active communication, check and management of hygiene. However regardless of their position or career, chefs in charge of the Western food have the same cognitive attitude toward selecting successful outsourcing companies after the outsourcing system is enforced. The core of cooking, or a final stage in the full process of so-called artistic cooking, should be treated with insourcing. Reduction of several cooking processes resulted in shortened cooking time, increased efficiency, faster cooking, cutting the waiting-lines, and finally more room for customers. The outsourcing system can reduce or eliminate the following processes in cooking: buying various food materials, checking, storing, preparing, and processing. Especially in the Western food cooking department of a hotel, the outsourcing system should be enforced to make an economic kitchen and to efficiently manage it. Wow it's time to change from the traditional kitchen to an economic kitchen in the hotel cooking department. For that, the cooking department should become a small but strong organization by outsourcing except its core work.

• Journal of Life Science
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• v.19 no.12
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• pp.1750-1757
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• 2009

The purpose of this study was to investigate the effects of regular walking exercise on health-related parameters in the elderly with chronic diseases - apoplexy, overweight, impaired fasting glucose, and overweight + impaired fasting glucose. A total of 85 subjects, 27, 17, 21 and 20 in apoplexy (A), overweight (O), impaired fasting glucose (IFG), overweight + impaired fasting glucose group (O_IFG), respectively, completed a 12-week walking exercise. The health-related parameters were measured before and at the completion of the exercise program including anthropometric measurements, functional physical fitness levels, blood pressure, fasting glucose, blood lipid profiles and chronic inflammatory markers (CRPs). Significant improvements in body weight, BMI, %body fat, blood pressure, all blood lipid measurements and all measured physical fitness items were shown in A; those in %body fat, TC, HDL-C and LDL-C in O; those in body weight, BMI, %body fat, fasting glucose, TC, TG and HDL-C in IFG; and those in body weight, HDL-C and LDL-C in O_IFG (p<0.05). The results of the present study demonstrated that a 12-week walking exercise brought positive effects on body weight, bloody lipid profiles, fasting glucose and functional physical fitness levels in the elderly with chronic diseases. In conclusion, this study suggested that walking regularly is very effective in lowering the risks of developing chronic diseases.

• Pediatric Infection and Vaccine
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• v.3 no.2
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• pp.175-184
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• 1996

Purpose : This study was intended to measure seropositivities and the levels of mumps- and rubella-specific IgG of MMR vaccinees over 17 months of age in Korea. Materials and Methods : From June 1994 to April 1995 we obtained sera from visitors of well baby clinic and patients in Korea University Hospital, who were MMR vaccinees over 17 months of age and had no evidence of immunodeficiency. These 275 study population include 145 males and 130 females. Mumps- and rubella-specific IgG antibody levels were measured by ELISA. Cut-off values for seropositivity were 20 GU(Gamma Unit) in mumps and 0.17 in rubella. Results : 1) As age increased, seropositivities of mumps-specific IgG increased significantly, being 69.0% in 1.5~2 year, 75.0% in 3~4 year, 76.0% in 5~6 year, 90.0% in 7 year, 100% in 8 year, 96.9% in 9 year, 97.4% in 10 year, 97.4% in 11 year, and 96.6% in 12 year of age(p<0.001). 2) As age increased, the levels of mumps-specific IgG antibody(mean${\pm}$standard deviation, GU) increased significantly, being $64.9{\pm}66.5$ in 1.5-2 year, $117.7{\pm}126.4$ in 3~4 year, $152.3{\pm}147.1$ in 5~6 year, $194.3{\pm}168.2$ in 7 year, $258.1{\pm}190.6$ in 8 year, $193.1{\pm}130.1$ in 9 year, $225.7{\pm}119.6$ in 10 year, $220.7{\pm}114.3$ in 11 year, and $222.3{\pm}127.1$ in 12 year of age(p<0.001). There was positive correlation between age and mumps-specific antibody level (r=0.3282, p<0.001). 3) As age increased, seropositivities of rubella-specific IgG decreased significantly, being 72.4% in 1.5~2 year, 75% in 3~4 year, 72% in 5~6 year, 60% in 7 year, 44.4% in 8 year, 40.6% in 9 year, 28.2% in 10 year, 23.1% in 11 year, and 17.2% in 12 year of age(p<0.001). 4) As age increased, rubella-specific IgG decreased significantly, being $0.462{\pm}0.356$ in 1.5~2year, $0.438{\pm}0.306$ in 3~4 year, $0.287{\pm}0.179$ in 5~6 year, $0.204{\pm}0.139$ in 7 year, $0.189{\pm}0.153$ in 8 year, $0.124{\pm}0.121$ in 9 year, $0.093{\pm}0.114$ in 10 year, $0.104{\pm}0.135$ in 11 year, and $0.080{\pm}0.001$ in 12 year of age(p<0.001). There was negative correlation between age and rubella-specific IgG titer (r=-0.551, p<0.001). Conclusions : Eventhough seropositivities and the level of mumps-specific IgG increased as age increased, they are not enough to prevent mumps infection in 1.5 to 6 years of age. Seropositivities and the level of rubella-specific IgG decreased as age increased. Appropriate change in vaccine schedule may be needed to decrease the risks of mumps and rubella infection.

• Journal of Food Hygiene and Safety
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• v.35 no.1
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• pp.51-59
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• 2020

This study evalutated the risk of foodborne illness from Vibrio spp. (Vibrio vulnificus and Vibrio cholerae) through sea squirt consumption. The prevalence of V. vulnificus and V. cholerae in sea squirt was evaluated, and the predictive models to describe the kinetic behavior of the Vibrio in sea squirt were developed. Distribution temperatures and times were collected, and they were fitted to probabilistic distributions to determine the appropriate distributions. The raw data from the Korea National Health and Nutrition Examination Survey 2016 were used to estimate the consumption rates and amount of sea squirt. In the hazard characterization, the Beta-Poisson model for V. vulnificus and V. cholerae infection was used. With the collected data, a simulation model was prepared and it was run with @RISK to estimate probabilities of foodborne illness by pathogenic Vibrio spp. through sea squirt consumption. Among 101 sea squirt samples, there were no V. vulnificus positive samples, but V. cholerae was detected in one sample. The developed predictive models described the fates of Vibrio spp. in sea squirt during distribution and storage, appropriately shown as 0.815-0.907 of R² and 0.28 of RMSE. The consumption rate of sea squirt was 0.26%, and the daily consumption amount was 68.84 g per person. The Beta-Poisson model [P=1-(1+Dose/β)^-α] was selected as a dose-response model. With these data, a simulation model was developed, and the risks of V. vulnificus and V. cholerae foodborne illness from sea squirt consumption were 2.66×10^-15, and 1.02×10^-12, respectively. These results suggest that the risk of pathogenic Vibrio spp. in sea squirt could be considered low in Korea.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.2
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• pp.65-74
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• 2013

A research program for the roe deer (Capreolus pygargus) has been set up at the Jeju Experimental Forest of Warm-temperate and Subtropical Forest Research Center in Jeju Island. To explore the home range size and habitat environment, 3 males and 3 females have been captured and released with GPS-CDMA based telemetry since 24th April 2012. Among them 2 females were captured at Hannam Forest of Seoguipo, were pregnant and monitored by the tracking system. There are significantly different patterns in behavior around the parturition. After parturition they show recurrence behavior toward one point in the forest, while they have irregular patterns in moving before. To calculate the home range size, the MCP (minimum convex polygon) and Kernel Method are applied through the extension of ESRI ArcView GIS 3.2a. The pregnant female captured 9th May 2012 has the size of MCP=67ha and Kernel 95%=0.5ha and the pregnant female captured 12th July 2012 has the size of MCP=82ha and Kernel 95%=0.9ha. Although a fawn could move immediately just after the birth likely others to avoid any risks, they stay at very narrow space significantly, and the size become wider when more time goes by. Furthermore, they mainly have a home range away from human activity area such as forest tracking roads. The habitat environment for the parturition is summarized as 40years old cryptomeria forests with new sprouting shrubs for foods, which are the controlled forest through the thinning and removing shrubs 2 years ago. This means that forest works could cause positive results for the parturition and survival of young. The period of parturition is earlier than highland in Jeju Island, the size of home range is narrower than other countries, and the habitat environment of the shelter for a fawn is similar to previous research in other countries.

• Asia pacific journal of information systems
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• v.23 no.4
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• pp.103-128
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• 2013

When a consumer needs a product or service and multiple sellers are available online, the process of selecting a seller to buy online from is complex since the process involves many behavioral dimensions that have to be taken into account. As a part of this selection process, consumers may set minimum trust expectation that can be used to screen out less trustworthy sellers. In the previous research, the level of consumers' trust expectation has been anchored on two important factors: product involvement and perceived risk. Product involvement refers to the extent to which a consumer perceives a specific product important. Thus, the higher product involvement may result in the higher trust expectation in sellers. On the other hand, other related studies found that when consumers perceived a higher level of risk (e.g., credit card fraud risk), they set higher trust expectation as well. While abundant research exists addressing the relationship between product involvement and perceived risk, little attention has been paid to the integrative view of the link between the two constructs and their impacts on the trust expectation. The present paper is a step toward filling this research gap. The purpose of this paper is to understand the process by which a consumer chooses an online merchant by examining the relationships among product involvement, perceived risk, trust expectation, and intention to buy from an e-tailer. We specifically focus on the mediating role of perceived risk in the relationships between enduring product involvement and the trust expectation. That is, we question whether product involvement affects the trust expectation directly without mediation or indirectly mediated by perceived risk. The research model with four hypotheses was initially tested using data gathered from 635 respondents through an online survey method. The structural equation modeling technique with partial least square was used to validate the instrument and the proposed model. The results showed that three out of the four hypotheses formulated were supported. First, we found that the intention to buy from a digital storefront is positively and significantly influenced by the trust expectation, providing support for H4 (trust expectation ${\rightarrow}$ purchase intention). Second, perceived risk was found to be a strong predictor of trust expectation, supporting H2 as well (perceived risk ${\rightarrow}$ trust expectation). Third, we did not find any evidence of direct influence of product involvement, which caused H3 to be rejected (product involvement ${\rightarrow}$ trust expectation). Finally, we found significant positive relationship between product involvement and perceived risk (H1: product involvement ${\rightarrow}$ perceived risk), which suggests that the possibility of complete mediation of perceived risk in the relationship between enduring product involvement and the trust expectation. As a result, we conducted an additional test for the mediation effect by comparing the original model with the revised model without the mediator variable of perceived risk. Indeed, we found that there exists a strong influence of product involvement on the trust expectation (by intentionally eliminating the variable of perceived risk) that was suppressed (i.e., mediated) by the perceived risk in the original model. The Sobel test statistically confirmed the complete mediation effect. Results of this study offer the following key findings. First, enduring product involvement is positively related to perceived risk, implying that the higher a consumer is enduringly involved with a given product, the greater risk he or she is likely to perceive with regards to the online purchase of the product. Second, perceived risk is positively related to trust expectation. A consumer with great risk perceptions concerning the online purchase is likely to buy from a highly trustworthy online merchant, thereby mitigating potential risks. Finally, product involvement was found to have no direct influence on trust expectation, but the relationship between the two constructs was indirect and mediated by the perceived risk. This is perhaps an important theoretical integration of two separate streams of literature on product involvement and perceived risk. The present research also provides useful implications for practitioners as well as academicians. First, one implication for practicing managers in online retail stores is that they should invest in reducing the perceived risk of consumers in order to lower down the trust expectation and thus increasing the consumer's intention to purchase products or services. Second, an academic implication is that perceived risk mediates the relationship between enduring product involvement and trust expectation. Further research is needed to elaborate the theoretical relationships among the constructs under consideration.