• The Korean Journal of Mycology
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• v.46 no.1
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• pp.34-42
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• 2018

Tricholoma matsutake (Pine mushroom) is expensive, and its artificial cultivation has been tried in several countries. Until date, the only successful cultivation of artificial pine mushroom in pine forests uses matsutake-infected pine trees. The National Institute of Forest Science in Korea has been restudying this method since 2000. Success in fruit production and reproduction was achieved in 2010 and 2017, respectively, in the same locale. The successes proved that pine mushrooms could be cultivated artificially in the field using matsutake-infected pine trees. The fruiting of pine mushroom in October 2010 occurred 6 years, 6 months after the transplantation of matsutake-infected pine trees. Five pine mushrooms reoccurred in September 2017, 13 years, 5 months and 15 years, 5 months after the transplantation of the respective matsutake-infected pine trees. The distance between the matsutake-infected pine tree and the pine mushrooms was 12 cm at 6.6 years, 90~115 cm at 13.5 years, and 95 cm at 15.5 years. Fruiting bodies occurred 13~16 days after the underground temperature declined to below $19^{\circ}C$. In conclusion, the use of matsutake-infected pine trees remains the only way to artificially cultivate pine mushrooms. More knowledge of the environmental factors affecting matsutake fruiting would be beneficial.

• Journal of Elementary Mathematics Education in Korea
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• v.23 no.1
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• pp.59-74
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• 2019

According to previous studies, it shows that the metacognitive ability that makes the positive element of the problem solver positively affects the problem-solving process of mathematics. In order to accurately grasp causality, this study investigates the specific characteristics of the meta-affect factor in the process of problem-solving. To do this, we analyzed the types and frequency of data collected from collaborative problem-solving situations composed of 4th~6th grade mathematically gifted children in small group of two. As a result, it can be seen that the type of meta-affect in the problem-solving process of mathematically gifted children is related to the correctness rate of the problem. First, regardless of the success or failure of the problem-solving, the meta-affect appeared relatively frequently in the meta-affect types in which the cognitive factors related to the context of problem-solving appeared first, and acted as the meta-functional type of the evaluation and attitude. Especially, in the case of successful problem-solving of mathematically gifted children, meta-affect showed a very active function as meta-functional type of evaluation.

• 대한공업교육학회지
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• v.33 no.1
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• pp.134-148
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• 2008

In this study, a survey was conducted to determine the understanding by teachers at KIPO-funded high schools of the specialized training of invention patent personnel. The subjects were 4 high schools and 126 copies of questionnaires were collected for analysis. The results of this study are as follows. First, teachers understand that it is particularly important to provide a specialized training for students so that they can more effectively adapt to the changes in their lives. They also consider basic job skills training, moral education and job readiness training as equally important. Second, they recognize the necessity for a specialized training of invention patent personnel. Third, they think that redundant teachers arising from the reform of the curriculum for specialized training should be provided with minor training. Fourth, they think that the reform of the curriculum for specialized training should consider the following aspects: the development of a curriculum for invention patent-specialized high schools, the strengthening of administrative financial supports, the creation of a consensus among those involved for the success of the specialized training, the development of textbooks and materials, and the consideration of the future prospects and current conditions of the invention patent industry. Fifth, they think that the successful operation of specialized high schools requires the consideration of the following factors: users' understanding, conformance, selection & concentration and uniqueness.

• Journal of radiological science and technology
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• v.21 no.1
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• pp.52-58
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• 1998

We can and must improve the diagnostic images using available knowledge and technology. At the same time we must strive to reduce the patient's integral and entrance radiation dose. Reducing the integral dose to the patient during the radiologic procedure is a primary concern of the patient, especially the pediatric patient, the radiologist and the technologist. A 100cm focal film distance generally is used for most over-table radiography. The early x-ray tubes and screen film combinations required long exposures, which often resulted in motion artifacts. But nowaday, we have the generators and x-ray tubes that can deliver the energy necessary in a very short time and the receptors that can record the information just as rapidly. And, we performed this studies to evaluate the patient exposure dose and the image quality by increasing focal film distance in diagnostic radiography. There are many factors which affected to exposure factor, but we studied to verify of FFD increase, only. Effect of increasing the focal film distance to a 140 cm distance was tested as follows; 1. The focal film distances were set at 100, 120, and 140cm. 2. A 18cm acryl(tissue equivalent) phantom was placed on the table top. 3. An Capintec 192 electrometer with PM 05 ion chamber was placed at the entrance surface of the phantom, and exposure were made at each focal film distances. 4. The procedure was repeated in the same manner as above except the ion chamber was placed beneath the phantom at the film plane. 5. Exit exposure were normalize to 8mR for each portions of the experiment. Based on the success of the empirical measurements, a detailed mathematical analysis of the dose reduction was performed using the percent depth dose data. The results of this study can be summerized as followings ; 1) Increasing FFD from 100 cm to 140 cm, we would create a situation that would have a significant effect on the overall quality of radiograph and achive the 17.42% reduction of entrance dose and the 18.95% reduction of integral dose that the patient receives. 2) Thickness of Al step wedge for equal film density increased with the long distance. 3) Increasing FFD, Magnification of image was lowered. 4) Resolution of image also increased with the FFD. As the results described above, we strongly recommend using the long FFD to provide better information for our patients and profession in abdomen radiographic studies.

• Asia pacific journal of information systems
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• v.23 no.2
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• pp.41-66
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• 2013

IS outsourcing has an important meaning to the Korean SME's (Small and Medium Enterprises) which want to use the IS Services. The objective of this research is to manage IT risks occurred during IS outsourcing project process. This study tries to identify these risks using real option methodology. In order to perform this objective, this study set up the research model which is composed of two main concepts. The first one is the risk factors occurred during IS outsourcing project process: User's Risks, Supplier's Risks and Transaction's Risks. All of these risks are based on Transaction Cost Theory. The second one is the intention to get (or buy) Real Options to manage the risks. In the research model, two types of real option are included: option to abandon (put option) and option to defer (call option). This study uses questionnaires and statistics methodology (PLS) to analyze the hypotheses proposed in the research model. Compared with prior studies, this study is different in two ways. First, this study restricts the range of IT risks. Prior researches of IT Risk management in MIS area cover various range of IT risks, but this study focuses on the Korean SME's IT outsourcing risks on the basis of Transaction Cost Theory. This study tests the relationship between the risks and real option types. Second, this study tries to test the moderating effect of user's risks and supplier's risks on the relationship between transaction's risks and real option types. In IT outsourcing research area, almost studies focus on the direct relationships between IT risks and outsourcing success. But in reality, the co-relationship among IT risks may occur. There are some findings according to the research analysis. First, risks related with user's risks have strong causal relationships with the intention to get option to abandon (put) and option to defer. But risks related with supplier's risks have causal relationships only with option to abandon (put). Second, user's risks and supplier's risks have no moderating effect on the relationship between transaction's risks and real option types. According to the research results, this research have some important and interesting implications on the IS outsourcing business area. First, this study identifies the effective types of real option to minimize the risks occurred during the IT outsourcing projects. So IS outsourcing service users can manage (or minimize) effectively the risks, which occurred during outsourcing projects, using real options. Second, real option gives benefits to suppliers and users at the same time (i.e., win-win strategies between IS outsourcing service providers and users). Vendors (:IS outsourcing service providers) can offer users the real options which can minimize the occurrence of risks in time. "IN TIME" means that before the IS outsourcing project starts, vendors can offer users the opportunity to buy real options in appropriate prices to manage the possibility of the risks of IS outsourcing project. And users also have chance to minimize the IT outsourcing risks occurred during the project process using real options.

• The Journal of Industrial Distribution & Business
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• v.10 no.10
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• pp.35-44
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• 2019

Purpose - This study focuses on the continuance intention of O2O fresh agricultural products e-commerce. By literature review, this paper looks through the classical theories which are often applied to study use behavior and continuance intention on the electronic commerce area. Ultimately based on the expectancy theory, Technology acceptance model, success model as well as trust model, a model of the continuance intention of fresh products O2O electronic commerce application is established. Research design, data, and methodology - Among users Chinese consumers have been chosen who have use experience as the research objects. From October 2, 2018 to November 2, 2018, 685 questionnaires in total were collected by the online release and collection. Expect for the negative questionnaires, the remaining 650 pieces of data are statistically analyzed. The collected data were firstly be analyzed by SPSS Ver. 25 on its frequency, reliability and exploratory factors. Then AMOS Ver. 25 is applied to the Confirmatory Factor Analysis, Discriminant Validity and hypothesis testing of the Structural Equation Modeling. Finally, the following research conclusions could be obtained from the hypothesis testing. Results - Firstly, in the extended IS model, quality factor for hypothesis testing, service quality, information quality and delivery quality have obviously present positive influences on satisfaction respectively. Secondly, in the hypothesis testing part of ECM-ISC model and UTAUT model, all hypotheses have presented accepted results. Especially from expectation confirmation to usefulness perception, the influence factor achieves 12.603, In the hypothesis of continuance intention, the influence factor of social influence on continuance intention is 7.748 and also it is the most remarkable one. Conclusions - The results show that the service quality of O2O fresh agricultural products e-commerce has the greatest impact on satisfaction, while the perceived usefulness of consumers has the most significant impact on O2O fresh agricultural products for sustainable use intention. This thesis makes up for the blank of O2O fresh food e-commerce for sustainable use intentions, and provides a theoretical basis for consumers' sustainable use behavior, and practical enlightenment for the sustainable development of O2O fresh agricultural products e-commerce.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.5
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• pp.105-113
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• 2019

This study focuses on analyzing the key success factors of the traditional market by analyzing the impact on the business performance of merchants in the traditional market. Based on the existing research on entrepreneurship, psychological characteristics, capabilities, and physical characteristics of the market were considered as merchant characteristics. As a result, the risk characteristics and merchant pride, which are internal characteristics of merchants, have a significant effect on business performance. Among the competencies of merchants, product competency, customer management competency, and price competency were found to have a significant impact on business performance. Among the physical characteristics of the market, reputation and product diversity were found to have a significant effect on business performance. The results of this study are meaningful to empirically prove the relevance of the merchant's internal characteristics and capabilities, and the market's physical characteristics to the business performance of market merchants. Could be utilized. However, the limitation of this study is that there may be differences in each industry in the case of market merchant products. In future studies, empirical studies on the trader's relevance to business capability and business performance should be continued.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.2
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• pp.193-198
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• 1997

To evaluate the efficacy of transabdominal myomectomy in the management of infertile patients, and to analyze on the results of abdominal myomectomy in 38 infertile patients with no other detectable cause except myomas were undertaken at the Department of Obstetrics and Gynecology in Yonsei University Hospital from 1990 to 1996. The results are as follows; 1. Average age of patients was 31.1 years. The infertility duration ranged 12 months to 144 months, and average infertility period of patients was 29.4 months. 2. Fourteen of the 38 patients (8 of 23 patients with primary infertility, 6 of 15 patients with secondary infertility) conceived following myomectomy, with a pregnancy rate of 36.8%. 3. Patients with less than 4 years of infertility showed a higher pregnancy rate after myomectomy than those with more than 4 years of infertility (42.4% vs 0%, p<0.05). 4. Patients younger than 35 years showed significantly higher pregnancy rate than those older than 35 years (46.4% vs 9.0%, p<0.05). 5. The removal of a solitary myoma produced a significantly higher pregnancy rate than that of multiple myomas (47.8% vs 20.0%, p<0.05), and the size of the myomas did not influenced the pregnancy rate after myomectomy (p>0.1). 6. The average time period from operation to conception was 12.1 months. Eight of the 14 patients (57.1%) conceived in the first year after operation and 12 patients (85.7%) condeived within two years. In conclusion myomas are a possible cause of infertility and myomectomy can be strongly recommended with good success expectation for the infertile women if uterine myoma be considered as the main cause of infertility. And factors affecting the pregnancy rate after myomectomy in these patients are the age of the patient, the duration of infertiluty, and the number of myoma.

• Tuberculosis and Respiratory Diseases
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• v.84 no.4
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• pp.282-290
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• 2021

Background: Radial probe endobronchial ultrasound-guided transbronchial lung biopsy (RP-EBUS-TBLB) has improved the diagnostic yield of bronchoscopic biopsy of peripheral pulmonary lesions (PPLs). The diagnostic yield and complications of RP-EBUS-TBLB for PPLs vary depending on the technique, such as using a guide sheath (GS) or fluoroscopy. In this study, we investigated the utility of RP-EBUS-TBLB using a GS without fluoroscopy for diagnosing PPLs. Methods: We retrospectively reviewed data from 607 patients who underwent RP-EBUS of PPLs from January 2019 to July 2020. TBLB was performed using RP-EBUS with a GS without fluoroscopy. The diagnostic yield and complications were assessed. Multivariable logistic regression analyses were used to identify factors affecting the diagnostic yields. Results: The overall diagnostic accuracy was 76.1% (462/607). In multivariable analyses, the size of the lesion (≥20 mm; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.27-3.33; p=0.003), positive bronchus sign in chest computed tomography (OR, 2.30; 95% CI, 1.40-3.78; p=0.001), a solid lesion (OR, 2.40; 95% CI, 1.31-4.41; p=0.005), and an EBUS image with the probe within the lesion (OR, 6.98; 95% CI, 4.38-11.12; p<0.001) were associated with diagnostic success. Pneumothorax occurred in 2.0% (12/607) of cases and chest tube insertion was required in 0.5% (3/607) of patients. Conclusion: RP-EBUS-TBLB using a GS without fluoroscopy is a highly accurate diagnostic method in diagnosing PPLs that does not involve radiation exposure and has acceptable complication rates.

• Journal of Life Science
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• v.31 no.10
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• pp.960-968
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• 2021

Since microalgae research started on late 18 century, they have been recognized as one of the most important bioresources used in bioindustry. Owing to the large efforts paid to industrial application of this microorganisms, their importance on food/feed and bioactive compounds has been further extending into the environmental research areas including alternative energy resources, mitigation of the carbon emission, and waste-water treatment. However, despite the importance on their industrial application, the fundamental research field related to the long-term preservation of microalgae culture has not received much attention. However, a less labor intensive and cost-efficient preservation technology enabling biologically active and stable microalgae-culture provides a key success factor in the biotechnological application. Therefore, this study investigated various cutting-edge microalgae cryopreservation technologies currently developed so far, mainly targeting Chlorophyta, which occupies the largest taxon in the classification system of microalgae. In addition, for the development of successful cryopreservation technique, the key factors such as temperature control effect and preservative effect during cryopreservation of microalgae culture were investigated. In addition, the problems with current preservation technology that is being used in Korean domestic biological resource banks and the international microalgal resource banks are described. According to our investigation, currently no standard method for long-term preservation of microalgae is available due to their various morphological and physiological characteristics. To overcome such issues, much more efforts on fundamental research area on the identification of specific biomarker used for microalgae taxonomical classification and further systemic approaches based on strain-specific cryopreservation methods needed.