• The Korean Journal of Nuclear Medicine Technology
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• v.14 no.2
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• pp.65-76
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• 2010

Purpose: he use of PET scanners and the number of patient in Korea have been increased for recent several years dramatically. For this reason, technologists have more possibilities to be exposed to the radiation. The hospitals using PET scanners should make an effort to reduce the radiation exposure dose. The purpose of this study was to evaluate the radiation exposure does when using radiation shielding devices. The evaluation was performed through questionnaire survey and experiment. Materials and Methods: First, the technologists who had experience working in PET center in 2008-2009 were surveyed with questionnaire and TLD Figures, personal opinion of utilization of radiation shielding devices are analyzed. Second, we measured the shielding rate of shielding devices which have been using in PET study procedures. We divided the procedures into four steps; distribution, moving, injection of $^{18}F$-FDG and patient setup. Results: First, the results of this survey, using of L-block+Syringe shield, L-block, Syringe shield, No shield during the injection, were each 58.5%, 20%, 9%, 12.3%. The TLD values according to utilization of radiation shield, using both L-block+Syringe Shield and L-block showed the lower TLD values, and Syringe shield only or No shield showed the higher TLD values. Second, the results of experiments according to PET study procedures measured the shielding rates as follows. The shielding rates during the distribution using L-block, L-block+Apron shield were measured 97.4%, 97.7%. The shielding rates during the $^{18}F$-FDG delivery to the injection room using mobile Syringe shield, Syringe holder, Syringe shield carrier were each 81.7%, 98.9%, 99.7%. The shielding rates during the injection using Syringe shield, L-block, L-block+Syringe shield were measured each 51.9%, 98.3%, 98.7%. The shielding rates of Apron were measured in each 30, 60, 90, 120, 150 cm distance. The measurement were each 16.9%, 14.2%, 16.6%, 17.1%, 18.1%, 18.6%. Conclusion: The most effective method for radiation shielding is to using L-block during the $^{18}F$-FDG distribution and Syringe shield carrier during in moving $^{18}F$-FDG. For the $^{18}F$-FDG injection, L-block+Syringe shield have to be used. The shielding effect of Apron has shown average 16.4%. According to the survey of questionnaire, the operators recognized well risk of the radiation exposure but, tended ignore in working. The radiation dose according to recognition of radiation exposure risk was not relevant. but radiation dose according to utilization of radiation shield lower the more use it. The main reason of no use of shielding devices is cumbersome, 55% of the respondents answered. I'm sure, by use of radiation shield in all PET procedure, radiation exposure will be reduced considerably.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.1-18
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• 2014

Recently, many of the mobile network operators or telcos are introducing the LTE service in order to effectively cope with an explosive increasing mobile traffics due to an expansion of the use of smart phones. The 1.8GHz, 2.6GHz, and 800MHz band classes are most widely used for LTE. In particular, the 1.8GHz band class is the most useful one in terms of the reusability of the existing (2G) network, global harmonization, bandwidth, eco-system of equipments and devices, and so on. In recent years, major countries in the world have allocated the 1.8GHz band spectrum in a wide bandwidth unit suitable for the upcoming LTE-Advanced service. This paper surveyed the 1.8GHz band spectrum allocation policies of the 12 OECD countries, including Republic of Korea. From the survey, we have found that they rebuilt or refarmed the existing holders' bands, recovered the public (i.e., military)-use bands, and allocated the bands in a wide bandwidth and in an equal or similar size.

• The Korean Journal of Pesticide Science
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• v.14 no.2
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• pp.116-122
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• 2010

This study was carried out to estimate the risk of pesticide operators who use high toxicological pesticides. The class II (highly hazardous) pesticides registered in korea were 15 products, and 11 products were spray type pesticides at orchard file in 2009. The using information based on the pesticide label and the data searched through survey of actual condition on pesticides were used for calculate the pesticide operator exposure dose. The risk quotients of these pesticides against the pesticides operator were calculated as devide pesticide exposure dose by reference dose which were presented by EFSA (European Food Safety Authority), JMPR (Joint FAO Meeting on Pesticide Residues), and US/EPA (United States Environmental Protection Agency). Omethoate showed the highest risk quotient and the values were 338 and 75 when the operator spray using speed sprayer and motor sprayer respectively. Risk quotients of all class II pesticide were above 1. This result means that the risk potential of these pesticides are very high.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.4
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• pp.284-291
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• 2017

There is no doubt that advances in UAV technology have improved military performance. However, these advances require humans to adapt to new and complex operational systems. UAV has been rapidly expanding to a variety of fields such as reconnaissance, transportation, communication and aerial photographing recently. Also, with the development of UAV automation technology, one operator is able to supervisory-control multiple-UAVs. However, as the number of assigned UAV increases, the amount of information increases and this results in the workload of the operator increasing and deterioration in controlling performance. Accordingly, there is a need for a model to determine the level of overload an operator may encounter with regard to multiple-UAV but nationally this kind of research is currently lacking. Therefore, this paper provides an experimental platform for evaluating workload index effectiveness integrating multiple-UAV operational environments, GCS, and eye-tracking system followed by a limited survey of domestic and international studies of multi-UAV overload studies.

• Management & Information Systems Review
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• v.28 no.4
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• pp.1-26
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• 2009

Among food-service managers, a survey was conducted to grasp the their work-related education conditions and the demand for education program development. This study focuses on food-service managers in web-based training and analyzes the critical factors involved in their learning process in order to clarify the factors that lead to the maximization of training programs. The results of all this study process are as follows. First, the characteristics of web-based education including component of education factor, system factor, deepening learning factor have meaningful effect on commitment of the participants and education performance(except deepening learning factor to education performance). Second, the analysis that the characteristics of individuals including self-efficacy in learning, purpose-directivity factor have meaningful effects on commitment of the participants and education performance(except purpose-directivity factor to education performance). Third, commitment of the participants has meaningful effects on the education performance. Thus, it is advisable for education managers or operators to emphasize in foodservice organizations.

• Journal of the Korean Institute of Navigation
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• v.21 no.2
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• pp.47-58
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• 1997

The purpose of this study is to find out the impacts of VTS on the marine safety and users' opinion on the VTS which have been being operated in the port of Pohang for the last 3 years and is to suggest a guideline to the successful operation of VTS in the future. This study is based upon the questionnaire survey and the respondents include 236 masters/mates of merchant vessels who have visited the port of Pohang and 6 pilots who have been working in the port. From the questionnaire results, this study notes the following conclusions related to the VTS operations. (1) A few of the respondents (mainly foreigners) do not understand the entering procedure of the port and the fundamental concept of VTS. Accordingly, the more active VTS services have to be provided for the mariners. (2) It was found that themost dangerous factors in tehvicinity of the port were the floating materials, fishing nets, andillegal fishing activities inthe fairway. Therefore, the proper surveillance, stricter enforcement of Acts and the instructive education for the fishermen are required to avoid the risks. (3) A majority of the respondents agreed the VTS has contributed to the safety of vessel traffic, and they pointed out ' the assiatances in reduced visibililty conditions' is the most important task of VTS. The amount of 75.6% of the respondents answered that they have experienced the assistance from VTS more than 1 time since the system was established in the port of Pohang . Also 44.2% of the respondents considered they were able to avoid marine casualties such as collision, ramming or agrounding with the VTS assistances. (4) 49.2% of the respondents preferred the passive information services , while, 38.8% of them preferred the positive control advices in the case of encountering any potential risks. VTS iperators have to consider seriously when they provide the positive control advices of ship's course and speed. (5) A majority of the respondents confirmed that the prot and its approaches is suitable for the VTS coverge . To extend the service areas of the VTS and to improve radar detecting ability, the use of radar transponders are seen as the ideal method. (6) A minority of the respondents pointed out 'the improper orders or recommendatinos caused by the poor decision making' firstly, ' the language problem(sea-speaking in English)' secondly, as the deficiency of personal qualification. It seems, therefore, theat the personal efforts of the operators and systematic training programmes for them are necessary to solve the problems.

• The Journal of Industrial Distribution & Business
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• v.8 no.6
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• pp.87-95
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• 2017

Purpose - The structural changes of Korean agriculture are complex due to heterogeneous production processes and farms' features. This study analyzed trends of dualism in Korean agriculture over the period 2000-15 based on farm-level data to clarify the specific trends of dualism in terms of farm income, farm-size, and farm operators' age. From the results of this study, we would be able to understand the features of structural changes in Korean agriculture more profoundly. Research design, data, and methodology - We incorporated farm-level data in South Korea: Agricultural census and Farm household economy survey. As measures of inequality, we used size-weighted quantiles, and normalized Gini coefficients as well as mean and conventional quantiles. The size-weighted quantiles are more robust to changes in the number of small farms, but they are more sensitive to changes in the distribution of farm-size. Thus, they would be more useful to identify trends of dualism of Korean agriculture. Results - The results show that the farmland distribution of crop farms became more skewed and dispersed. However, the herd distribution of livestock farms became more concentrated. To be specific, their mean and 1st quantile increases more rapidly than their size-weighted 2nd quantile and size-weighted 3rd quantile. Gini coefficients of livestock farms regarding their herd distribution decreased by 0.1 on average. In the case of income distribution, the results indicate that the polarization regarding farm household/agricultural/non-agricultural income became more severe. However, we also found that the distribution of transfer income became concentrated continuously. The results imply that transfer income including subsidies would decrease farm income polarization. Lastly, during the study periods, Korean farms were aging over time, and age distribution of them more concentrated. Conclusions - The structure of Korean agriculture has been changing, even though the absolute size of it decreased over time. Land (herd) distribution became more dispersed (concentrated). Inequality regarding agricultural income became more severe, and it made farm household income more polarized even though transfer income would decrease income gaps among farms. Lastly, farms continue to age regardless of farm types and this might affect the structural changes in Korean agriculture in the future.

• Journal of agricultural medicine and community health
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• v.43 no.2
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• pp.97-107
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• 2018

Objectives: The purpose of this study was to examine the success and barrier factors of hypertension registration program in Goseong community health center proven improving hypertension treatment rate by community health survey. Methods: We conducted a qualitative research using both a performance review of the program and in-depth interviews with the 8 operators who had worked for this program in April 2018. Results: In this study, the success factors were analysed as follows: First, the willingness to improve health indicators, second, the implementation of large-scale projects, third, improving program processes, fourth, continuous efforts for achievement of goal, not output or reward, and the barrier factors are as follows. First, uniform output monitering, second, evaluation after the fashion of contest, third, the confusing concept of an integrated health promotion program, fourth, the attitude of the person worried with task change. Conclusions: This study suggested that the health community health center should follow the basic principles of public health, and the central government should introduce a health policy of decentralization.

• Culinary science and hospitality research
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• v.20 no.6
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• pp.1-12
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• 2014

This study was conducted by empirically analyzing the relation between effects of positive emotional response of female customers, who have at some point consumed food at Korean restaurants in Busan, and behavioral intention according to their food service consumption propensity. In order to achieve the objective of the study, the questionnaire survey was performed from March $10^{th}$ to $25^{th}$, and frequency analysis, confirmatory factor analysis, reliability analysis, correlation analysis, and SEM (structure equation model) were conducted by using SPSS 18.0 and AMOS for 248 questionnaires. As a result of an exploratory factor analysis, five factors were confirmed. In a confirmatory factor analysis, the average variance extracted (AVE) and composite reliability (CR) were confirmed as .508 to .665 and .905 to .946 respectively, which proved the convergent validity. In a hypothesis test, Hypothesis 1 was determined that the food service consumption propensity positively effects on emotional response. The results were as follows: the taste driven (${\beta}$=.325, t=3.907, p<.001), the health driven (${\beta}$=.190, t=2.688, p<.001), and the atmosphere driven (${\beta}$=.188, t=2.515, p<.001). Therefore, Hypothesis 1 was selected. Hypothesis 1 has determined that positive emotional response beneficially affects behavioral intention. As a result of an analysis, the standardized path coefficient was (${\beta}$=.496, t=6.388, p<.001), so Hypothesis 1 was selected. This result suggests that the taste driven factor has the biggest influence on emotional response in the food service consumption propensity for female customers, and food service business operators should strive to make a good restaurant atmosphere for customers to get positive emotional response (pleasure, comfort, satisfaction, and joy).

• Journal of the Korea Society of Computer and Information
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• v.24 no.12
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• pp.75-84
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• 2019

The Naval Combat System has several equipment needed to operate the system, such as radar equipment, underwater sensor equipment, guns and missile control and armed control equipment, and a multi function console is configured to control it. The multi function console is equipped with HCI(Human Computer Interaction)-based software for displaying the status information of equipment and controlling equipment, and the operator uses the installed software to operate the Naval Combat System. However, when operating a Naval Combat System for a long time, there are problems such as physical discomfort caused by the structure of the multi function console display and increase in fatigue of the person who operates various and complicated user interface configuration. These issues are important factors in reducing Naval Combat System operability. In order to solve these issues, in this paper, based on a questionnaire survey conducted for Naval Combat System development personnel, multi function console screen design to reduce physical discomfort and HCI design to reduce fatigue and increase intuition are proposed. The proposed design is expected to provide convenience to future Naval Combat System operators and improve operation over existing Naval Combat System.