• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.1
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• pp.17-21
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• 1991

The study was performed to investigate the effects of gaseous emission of sulfur dioxide and hydrogen fluoride on the growth of rice plant under stressed field conditions. This study is specifically dealt with multiple effects of sulfur dioxide and hydrogen fluoride on various plant growth indicators such as leaf damage, weight of grain, panicles per hill, spikelets per panicle and percent fertility. It appears that there is a good correlation between ambient concentrations of sulfur oxides and sulfur contents found in leaves with an average correlation coefficient of 0.868 within a 1% significance level. A better multiple correlation was found between percent leaf damage and sulfur and fluorine contents found in leaf with a significance of 1% level. The correlation coefficient ranges from 0.807 to 0.978 with an average being 0.922. An evaluation of data observed has demonstrated that both panicles per hill and percent fertility are significantly affected by air pollutants. As expected, hydrogen fluorides have more effects than sulfur oxides. It is, however, interesting to note that spikelets per panicle has slightly been affected while no indication of effects on l000-grain weight has been observed. This may lead to a conclusion that a reduction in yield of rice under polluted field conditions may have more been caused by the diminution panicles per hill and percent fertility rather than by the diminution of spikelets per panicle and grain weight.

• The Korean Journal of Nuclear Medicine Technology
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• v.15 no.1
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• pp.106-112
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• 2011

Purpose: Until now, the process was improved by the needs of experimenters personally. But recently, suggestion system in hospital has been activated in various ways. So the department of nuclear medicine laboratory is also aware of the need of operation improvement using suggestion system. It is intend to assist in the development by sharing excellent suggestion cases with other hospitals. Material & Method: A total of 124 suggestion cases from January 2007 to March 2010 were analyzed. Suggestion cases were divided into customer satisfaction, cost reduction, improved testing methods, equipment, environmental improvement, and computational system. Result: Suggestion cases of environmental improvement and computational system were accounted for 26.6% as 33 cases, respectively. Suggestion for customer satisfaction is 25.8% as 32 in a total of 124 cases. Conclusion: Activation of the awareness of operation improvement is induced by suggestion system. By securing system of operation improvement, employees' ideas can lead to the production and systematization. Furthermore, it enhances hospital competitiveness and promotes the development of the hospital.

• Korean Journal of Human Ecology
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• v.7 no.1
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• pp.33-41
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• 2004

The purpose of the study was to analyze in process of circulation market boiled whale meat's rancidity. oxidative rancidity is oil or fat food depend on oxygen in air oxidative change in quality. boiled whale meat faty come to oxidative rancidity food stability and hygiene reasons for people health poisonous point out, however it is not indication study of support. Accordingly confirm lead into circulation process boiled whale meat's rancidity examination and microorganism examination boiled whale meat's stability whether or not. The result obtained were summarized as follows: 1. Proximate percentage of boiled whale meat(pectoral, pelvic, fin, flank) of moisture and crude lipid and crude protein from samples shown to be : moisture was pectoral 16.4%, pelvic 36.2%, fin 46.2%, flank 19.2%, crude lipid was pectoral 54.1%, pelvic 42.8%, fin 15.8%, flank 40.6%,crude protein was pectoral 29.4%, pelvic 20.5%, fin 29.5%, flank 28.6%. 2. The fatty acid composition of total lipid were composed of pectoral 27.2%, pelvic 28.9%, fin 33.3%, flank 23.4% of oleic acid and pectoral 12.7%, pelvic 11.1%, fin 11.3%, flank 14.0% of palmitic acid pectoral 10.8%, pelvic 7.9%, fin 7.6%, flank 2.1% of docosahexaenoic acid, pectoral 14.2%, pelvic 7.5%, fin 1.9%, flank 7.2% of eicosenoic acid, pectoral 5.1%, pelvic 5.7%, fin 4.4%, flank 5.7% of myristic acid, 16: 0 11∼14 % of high saturated fatty acid. generally most of 18: 1ω9 of boiled whale meat's each portion, 22:6 7∼12%, 20:5 1∼14% of polyenoic fatty acid. 18:3 showen to be 1% make an expection of pectoral and fin portion the total lipid were most of netural lipid's about 90%, monoenic fatty acid were most of 19∼22% of saturated fatty acid, 77∼80% of monoenic fatty acid level of 47∼56% of 18:1 16:1 was markelly high to those of total lipid. 3. The storage number days variation of oxidation were shown to be by stages process favorably the past days of boiled whale meat's acid value for 5days. pectoral the day 0.1, five days 1.3, pelvic the day 0.1, five days 1.6, fin the day 0.3, five days 0.7, flank the day 0.2, five days 0.4. 4. The sealer and wrapper the storage number days variation of boiled whale meat oxidation for 7days were shown to be a stage of sealing, the temperature of a room, pectoral the day 0.1 seven days 0.6, pelvic the day 0.1, seven days 1.3, fin.

• Parasites, Hosts and Diseases
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• v.57 no.4
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• pp.341-357
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• 2019

Acanthamoeba, one of free-living amoebae (FLA), remains a high risk of direct contact with this protozoan parasite which is ubiquitous in nature and man-made environment. This pathogenic FLA can cause sight-threatening amoebic keratitis (AK) and fatal granulomatous amoebic encephalitis (GAE) though these cases may not commonly be reported in our clinical settings. Acanthamoeba has been detected from different environmental sources namely; soil, water, hotspring, swimming pool, air-conditioner, or contact lens storage cases. The identification of Acanthamoeba is based on morphological appearance and molecular techniques using PCR and DNA sequencing for clinico-epidemiological purposes. Recent treatments have long been ineffective against Acanthamoeba cyst, novel anti-Acanthamoeba agents have therefore been extensively investigated. There are efforts to utilize synthetic chemicals, lead compounds from medicinal plant extracts, and animal products to combat Acanthamoeba infection. Applied nanotechnology, an advanced technology, has shown to enhance the anti-Acanthamoeba activity in the encapsulated nanoparticles leading to new therapeutic options. This review attempts to provide an overview of the available data and studies on the occurrence of pathogenic Acanthamoeba among the Association of Southeast Asian Nations (ASEAN) members with the aim of identifying some potential contributing factors such as distribution, demographic profile of the patients, possible source of the parasite, mode of transmission and treatment. Further, this review attempts to provide future direction for prevention and control of the Acanthamoeba infection.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1327-1337
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• 2018

Aviation fuel oil is more strictly controlled than other transport fuels because it can lead to major accidents in the event of a problem. The quality standards of the aircraft are specified by the domestic Korean Standard, the American Society for Testing and Materials and the International Air Transport Association, respectively. From 2016 to 2017, the quality analysis of 6 items such as aromatic content, sulfur content and distillation characteristics was carried out on the jet fuel produced at five domestic refineries. Domestic production of jet fuel has been shown to be in conformity with the quality standards and has been maintained at a constant level throughout the year. Compared with the specification of ASTM and IATA the aromatic content of domestic KS specification is set to be strictly 1.5 wt% higher than the ASTM and IATA setting specification, but it satisfies this specification sufficiently. In addition, other items such as sulfur content, distillation property and flash point satisfied both domestic and international specification.

• Korean Journal of Agricultural and Forest Meteorology
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• v.24 no.4
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• pp.201-217
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• 2022

The United States is one of the largest producers of major crops such as wheat, maize, and soybeans, and is a major exporter of these crops. Therefore, it is important to estimate the crop production of the country in advance based on reliable long- term weather forecast information for stable crops supply and demand in Korea. The purpose of this study is to improve the seasonal predictability of the agro-climatic indices over the United States by using regional-scale daily temperature. For long-term numerical weather prediction, a dynamical downscaling is performed using Weather Research and Forecasting (WRF) model, a regional climate model. As the initial and lateral boundary conditions of WRF, the global hourly prediction data obtained from the Pusan National University Coupled General Circulation Model (PNU CGCM) are used. The integration of WRF is performed for 22 years (2000-2021) for period from June to December of each year. The empirical quantile mapping, one of the bias correction methods, is applied to the timeseries of downscaled daily mean, minimum, and maximum temperature to correct the model biases. The uncorrected and corrected datasets are referred WRF_UC and WRF_C, respectively in this study. The daily minimum (maximum) temperature obtained from WRF_UC presents warm (cold) biases over most of the United States, which can be attributed to the underestimated the low (high) temperature range. The results show that WRF_C simulates closer to the observed temperature than WRF_UC, which lead to improve the long- term predictability of the temperature- based agro-climatic indices.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.195-221
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• 2009

According to an industry report, a large number of organizations have invested in Organizational Information System(OIS) in the past few years. Several research results indicate that successful investments in OIS lead to productivity enhancement, while failed ones result in undesirable consequences such as financial losses and dissatisfaction among employees. In spite of huge investments, however, many organizations have failed in achieving the hoped-for returns from OIS. Thus, understanding user acceptance, adoption, and usage of new IS(Information Systems) is an important issue for IS practitioners. Indeed, study of the user acceptance of new information system has been one of the most important research topics in the contemporary IS literature. Several theoretical models are tested to examine 'user acceptance' and 'usage behavior' in IS context. While many research models incorporate 'ease of use' or 'usefulness' as important factors in explaining user acceptance, Technology Acceptance Model(TAM) has been one of the most widely applied models in user acceptance and usage behavior. Even in recent IS studies that employ theories of innovation diffusion in the area of IS implementation, a major focus has been on the user's perception of information technologies. In this research, we study 'voluntariness' as an important factor in IS acceptance by users. Voluntariness is defined as "the degree to which the use of the innovation is perceived as being voluntary, or of free will" When examining the diffusion of accepting OIS, a thoughtful consideration should be given to 'perceived voluntariness.' Current article has following research questions: 1) What models are appropriate to explain the success of OIS? and 2) How does the 'voluntariness' affect the success of OIS? In order to answer these questions, a research model is proposed to describe the detailed nature of association among three independent variables (IT usage level, task interdependency, and organizational support), a mediating variable (IS usage), a dependent variable (perceived performance), and a moderating variable(perceived voluntariness). The central claim of this article is that organizations hardly realize expected returns from OIS investments unless perceived voluntariness is effectively managed after operating OIS. As an example of OIS in this study we have selected the Intranet of Republic of Korea Air Force (ROKAF). ROKAF has implemented the Intranet in an attempt to improve communication and coordination within the organization. To test our research model and hypotheses, survey questionnaires were first sent out to 400 Intranet users. With the assistance of ROKAF, Intranet users were initially identified among its members, and subjects were randomly drawn from the pool. 377 survey responses were finally returned. The unit of measurement and analysis in this research is a personal level. Path analysis based on structural equation modeling was used to test research hypotheses. Construct validity represents accordance between the theoretical base concept of constructs and its measurement items. Tests for the reliability and discriminant validity are accepted, thus verifying our survey instrument. In this research, we have proposed a conceptual framework to highlight the importance of perceived voluntariness after organization deploys OIS. The results of our analysis present several key finding. First, all three independent variables (IT usage level, task interdependency, and organizational support) have significant effects on IS usage, which will eventually improve performance. Thus, IS usage plays a mediating role between antecedent variables (IT usage level. task interdependency, and organizational support) and performance improvement. Second, the effect of the task dependency was the highest for IS usage among the three antecedent variables. This is highly plausible since one of the Intranet's major capabilities is to facilitate communication among members within an organization. Accordingly, we conclude that the higher the task dependency, the higher Intranet usage. The effect of user's IT usage level was the second, while the effect of the organizational support was the third. Finally, the perceived voluntariness plays a pivotal role in enhancing perceived performance in personal level after launching the Intranet. Relationships among investigated variables were significantly different between groups with a high level and a low level of voluntariness. The impact of the Intranet usage on the performance was greater in the higher level voluntariness group than in the lower one. For the lower level voluntariness group, the user's IT usage had the highest effect on the Intranet usage among the three antecedent variables. In short, our study suggests that the higher the perceived voluntariness is the more IS usage will be. Perceived voluntariness was found to have a moderating effect on the relationships among user IT usage level, task interdependency, IS usage, and perceived performance, supporting all the hypotheses on the moderating effect. Most of all, user IT usage level has the strongest influence on IS usage, indicating that users with superior IT usage are more likely to enjoy a high level of perceived performance.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.52-60
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• 2005

In this study, low density polyethylene/organo-clay nanocomposites were prepared by melt blending. Thermal property, structure, and morphology of the LDPE/organo-clay nanocomposites were investigated. When the composition ratios of the compounds of LDPE/PE-g-MA/organo-clay were 90/10/1~10 (w/w/w), X-ray diffractograms of LDPE/organo-clay nanocomposites revealed that the intercalation of polymer chains lead to increase the spacing between clay layers. TEM microphotographs showed that LDPE was intercalated into organo-clay. TGA performed under air atmosphere demonstrated a great increase in thermal stability of the LDPE/organo-clay nanocomposties. The maximum decomposition temperature of LDPE/organo-clay nanocomposite was increased about $80^{\circ}C$ compared with pure LDPE. When the organo-clay contents were 1.0~5.0 wt%, the LOI values were increased with increasing the organo-clay content, but in the case of the contents more than 5.0 wt%, the LOI values were not increased any more.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.37-43
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• 2017

This review investigates the basic principle of physical interactions and failure mechanisms introduced in the materials and inner parts of semiconducting components under electromagnetic pulses (EMPs). The transfer process of EMPs at the semiconducting component level can be explained based on three layer structures (air, dielectric, and conductor layers). The theoretically absorbed energy can be predicted by the complex reflection coefficient. The main failure mechanisms of semiconductor components are also described based on the Joule heating energy generated by the coupling between materials and the applied EMPs. Breakdown of the P-N junction, burnout of the circuit pattern in the semiconductor chip, and damage to connecting wires between the lead frame and semiconducting chips can result from dielectric heating and eddy current loss due to electric and magnetic fields. To summarize, the EMPs transferred to the semiconductor components interact with the chip material in a semiconductor, and dipolar polarization and ionic conduction happen at the same time. Destruction of the P-N junction can result from excessive reverse voltage. Further EMP research at the semiconducting component level is needed to improve the reliability and susceptibility of electric and electronic systems.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.75-89
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• 2004

Long term performance of concrete pavement significantly depends on the given construction and environmental condition. It means that random cracks and extreme crack width due to inappropriate quality control at the early age might lead to decreasing the pavement service life. The temperature and moisture during the construction, cement and aggregate types, curing condition are major components to affect the quality of the concrete pavement at the early age. First of all, the high temperature differential, that is made by increasing air temperature and the heat of cement hydration, is known as the major contributor to severe cracks. In this study, tent covering was used for controlling temperature of the concrete slab. The field measurement data indicates that the effect of the tent covering is very significant to decrease possibilities of random crack occurrence and curling stress and enhance the long-term concrete strength. HIPERPAV(High PERformance PAVing software), a program predicting the strength and stress of an earty-age concrete pavement (72 hour after placement), is used for simulating the effects of tent covering. The HIPERPAVE results showed that the section with the tent covering has higher reliability than the section without the tent covering by 22.5%. In details, reliability is increased 72.5% (without the tent covering) to 95% (with the tent covering).