• Journal of the Korean Magnetic Resonance Society
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• v.5 no.2
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• pp.99-109
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• 2001

Authors investigated neuronal changes of local cellular metabolism in the cerebral lesions of Parkinsonian symptomatic side between before and after stereotactic neurosurgery by follow-up 1H magnetic resonance spectroscopy (MRS). Patients with Parkinson's disease (PD) (n = 15) and age-matched normal controls (n = 15) underwen MRS examinations using a stimulated echo acquisition mode (STEAM) pulse sequence that provided 2${\times}$2${\times}$2 ㎤ (8ml) volume of interest in the regions of substantia nigra, thalamus, and lentiform nucleus. Spectral parameters were 20 ms TE, 2000 ms TR, 128 averages,2500 Hz spectral width, and 2048 data points. Raw data were processed by the SAGE data analysis package (GE Medical Systems). Peak areas of N-acetylaspartate (NAA), creatine (Cr), choline-containing compounds (Cho), inositols (Ins), and the sum (Glx) of glutamate and GABA were calculated by means of fitting the spectrum to a summation of Lorentzian curves using Marquardt algorithm. After blindly processed, we evaluated neuronal alterations of observable metabolite ratios between before and after stereotactic neurosurgery using Pearson product-moment analysis (SPSS, Ver. 6.0). A significant reduction of NAA/Cho ratio was observed in the cerebral lesion in substantia nigra of PD patient related to the symptomatic side after neurosurgery (P : 0.03). In thalamus, NAA/Cho ratio was also significantly decreased in the cerebral lesion including the electrode-surgical region (P : 0.03). A significant reduction of NAA/Cho ratio in lentiform nucleus was not oberved, but tended toward significant reduction after neurosurgery (P = 0.08). In particular, remarkable lactate signal was noted from the surgical thalamic lesions of 6 among 8 patients and internal segments of globus pallidus of 6 among 7 patients, respectively. Significant metabolic alterations of NAA/Cho ratio might reflect functional changes of neuropathological processes in the lesion of substantia nigra, thalamus, and lentiform nucleus, and could be a valuable finding fur evaluation of Parkinson's disease after neurosurgery. Increase of lactate signals, being remarkable in surgical lesions, could be consistent with a common consequence of neurosurgical necrosis. Thus, IH MRS could be a useful modality to evaluate the diagnostic and prognostic implications fur Parkinsons disease after functional neurosurgery.

• The Korean Nurse
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• v.33 no.3
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• pp.56-69
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• 1994

This study was done to develop self - directed learning modules related to asepsis and elimination including urine and stool for Fundamentals in Nursing practice education contents and to measure the effectiveness of those modules. The subjects of this study were 96 sophomore students in the nursing college. Self-directed learning modules were developed by the researcher on the basis of the Lippincott Learning System of Kruger (1986) and Modules for Basic Nursing Care of Ellis (1992). Videotape was editted by using videotape made by the Lippincott Company and Film strip made by the Trainex Company with Korean dubbing. Self-directed learning was done for one week with the asepsis module and two weeks with the elimination modules after confirming the requiered level of knowledge acquisition through pre-test. For measuring proficiency in self-directed learning, a written test for cognitive domain, a sufficiency test for psychomotor domain, and a confidnece examination for affective domain were given. The data were analyzed using descritive statistics, and Pearson correlation coefficient using a SPSS-PC program. The results are summarized as follows: 1. Sufficiency test and confidence examination grades showed high levels in both asepsis and elimination. 2. Written test grades showed a high level in asepsis and elimination of urine but showed a medium level in eliminationin of stool. 3. Grades of sufficiency and confidence in asepsis and elimination practice were statistically significant with a moderate positive correlation (r=0.4- 0.5, p<0.001). 4. Grades of sufficiency and written tests in asepsis and elimination practice also were statistically significant with a moderate positive correlation (r=0.5-0.7, p<0.001). 5. Students showed relatively high contentment with the self-directed learning modules themselves but revealed relatively low contentment with video program and the self-directed learning process. In conclusion, this study disclosed that proficiency levels in cognitive, affective, and psychomotor domains were high when asepsis and elimination modules were applied. Also students showed high satisfaction with the modules themselves, but didn't show high contentment with the video programs. In considering low contentment with the self-directed learning process, it is estimated the students had experienced some difficulties about using self-directed learning modules because this was their first exposure to the self-directed learning module and they were already accustomed to the demonstration-practice method.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.54-63
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• 2010

The recently-introduced Special Use Permit system is an exceptional approval system for private park developers to develop unexecuted urban park sites into urban parks with the implementation of profit-generating businesses within the boundary of preserving the original function of the park under an agreement with local authorities. This thesis studies the application of this system. This is a feasibility study of cases that have contributed to the acceptance of intended park sites by developing some parts of park sites as public housing, focused on unexecuted urban park areas for the long term in Suwon City based on the Special Use Permit, and creating other sites as park area. First, it has been judged that realization of business is possible at 300 percents of the floor area ratio in case of flatland neighborhood park which has high appraised land values. It is judged that realization of business is possible within a 10 percents size of private land at 200 percents of the floor area ratio in case of woodland and waterside neighborhood parks that have low appraised land values on the outskirts of the city. Second, through working expenses combining compensation and money for park construction, a balance of business profit can be understood within about 50 percents of total expenditures. Because the public contribution ratio by the Special Use Permit can be presumed as about 50 percents of total expenditures, it implies that windfall profits by the Special Use Permit can be adequately collected.

• Journal of Navigation and Port Research
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• v.39 no.1
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• pp.77-82
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• 2015

Slamming means that the hull hits the waves and receives impact pressure. This slamming effect may cause harm to people and when you put the hull at risk. so it is very harmful for cargo safety. Therefor slamming impact pressure should be fully considered in ship designing. In this study the model of wedged type structure are produced aimed to simulate a free fall that the experiments were carried out on different weight and free fall height. The flow field has been obtained by 2-frame grey level cross correlation PIV(Particle Image Velocimetry) method and experiment was divided into water entry and water exit. The impact pressure of free fall structure by a pressure acquisition system apply to dewetron system. The angles between a model and the water surface are adapted $15^{\circ}$ respectively. The weight change of models was given as 1.5, 1.8 and 2.0kg. To study slamming phenomenon for free fall height the experiments were carried out by the free fall height of 100, 200 and 300mm. The experimental value of the impact pressure according to the changes in weight was increase impact pressure in proportion to the increase in weight and higher free falling height has also influenced the increase in impact pressures.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.3
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• pp.244-250
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• 2018

Multilateration acquires the transponder signal of target from receivers installed on the ground and calculates the position of the target using the difference of the signal acquisition time of each receiver. One of the factors that influence the positioning accuracy of Multilateration using the TDOA calculation method is the error due to the precision measurement of signal input time. When measuring the signal input time at the receiver, the input signal is sampled using the reference clock of the receiver and a reference sample having the same sampling rate is applied to the cross correlation technique. Therefore, the accuracy of the signal input time is proportional to the reference clock. In this paper, the algorithm for precisely measuring the signal input time by performing cross correlation between the input signal of the receiver and DRS(Delayed Reference Sample) is proposed. In order to verify this, we implemented the pulse signal of the transponder that is transmitted from the target using Matlab. Through the simulation, cross correlation between the proposed DRS and the input signal was performed. From this result, the performance of the precise measurement of signal input time was analyzed.

• Journal of Broadcast Engineering
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• v.22 no.2
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• pp.214-233
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• 2017

For people with physical or sensory limitations, broadcasting is the main means of information acquisition and leisure. Recently, changes in the media environment, such as convergence of broadcasting and communication, digital mobile conversion of broadcasting, and active media usage behavior of users, make broadcasting accessibility of the disabled difficult, and as a result, the information gap between the disabled and the non-disabled is increasing. A notice on broadcasting rights for the disabled was enacted in consequence of the amendment of the Broadcasting Law in July 2011 and the web accessibility guideline became more effective with the amendment of the National Informatization Act in 2013 so that legal basis for the right of media access for the disabled was established. However, media services for them are still lacking quantitatively and qualitatively. In this study, we describe the present status of the audio description service for the visually impaired, and analyze the results of the questionnaire survey on the usage status, satisfaction and improvement requirements of the audio description service for 100 visually impaired people.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.99-116
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• 2018

The purpose of this study is to suggest the integrated entrepreneurial competency models that reflect critical entrepreneurial competencies that entrepreneurs should have at different stages, thereby enhancing the success rate of ventures. To accomplish the purpose, this study developed the hypotheses about the positive effects of entrepreneurial competencies on business performance, and the moderating effect of learning competency to strengthen the relationship between entrepreneurial competencies and business performance. The results of this study are as follows. First, the technological functional competency of entrepreneurial teams, the resource utilization and business planning competency of entrepreneurs in the early stage of business development were found to significantly affect both non-financial and technological performance. The opportunity recognition competency has a significantly positive effect on non-financial performance. In addition, it is analyzed that learning competency significantly moderated the relationship between entrepreneurial competencies(technological functional, resource utilization) and non-financial performance. The moderating effect of learning competency between business planning competency and technological performance was also found to be significant. Second, leadership and resource acquisition competency of entrepreneurs in the late stage of ventures have significantly positive effects on both non-financial and technological performance. The strategic competency has a significantly positive effect on non-financial performance. It was also found that the moderating effect of learning competency between strategic competency and non-financial performance was significant. Finally, the results show that both non-financial and technical performance of NTBVs are significant determinants of financial performance.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.3
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• pp.145-158
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• 2020

Because individuals come together to form a society, society has characteristics that are different or similar. Furthermore, as globalization and language acquisition in other countries have been activated, the frequency of studying abroad has increased. While Korea also studies abroad, the number of students coming to Korea from other countries continues to increase, increasing. In particular, when there was interest in start-up businesses, the factors were discovered through exploratory research in order to identify factors affecting the level of growth in start-ups when they had different nationalities. In order to conduct exploratory research, the government wanted to check more in-depth information through semi-structured interviews with co-founder companies composed of Koreans and Chinese. The main keywords were repeated or emphasized continuously during the interview, and other keywords were obtained through additional questions. As a result, it has been confirmed that self-acceptance, cultural distance, entrepreneurship, knowledge quality and growth are very large keywords in the co-founding start-up of different countries. The proposition was established as having a relationship of justice with self-acceptance, cultural distance and entrepreneurship as independent variables and with the degree of growth as dependent variables. In particular, in the case of co-founding with different nationalities, the most important knowledge quality was represented the effect of reverse U in each relationship (the relationship between self-acceptance, cultural distance, entrepreneurship and growth).

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.3
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• pp.181-189
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• 2016

An analytical model was developed by Sim to estimate the two-phase damping ratio for upward two-phase flow perpendicular to horizontal tube bundles. The parameters of two-phase flow, such as void fraction and pressure loss evaluated in the model, were calculated based on existing experimental formulations. However, it is necessary to implement a few improvements in the formulations for the case of tube bundles. For the purpose of the improved formulation, we need more information about the two-phase parameters, which can be found through experimental test. An experiment is performed with a typical normal square array of cylinders subjected to the two-phase flow of air-water in the tube bundles, to calculate the two-phase Euler number and the two-phase friction multiplier. The pitch-to-diameter ratio is 1.35 and the diameter of cylinder is 18mm. Pressure loss along the flow direction in the tube bundles is measured with a pressure transducer and data acquisition system to calculate the two-phase Euler number and the two-phase friction multiplier. The void fraction model by Feenstra et al. is used to estimate the void fraction of the two-phase flow in tube bundles. The experimental results of the two phase friction multiplier and two-phase Euler number for homogeneous and non-homogeneous two-phase flows are compared and evaluated against the analytical results given by Sim's model.

• Investigative Magnetic Resonance Imaging
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• v.9 no.1
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• pp.50-56
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• 2005

Contrast extravasation in hyperacute intracerebral hemorrhage (ICH) indicative of active bleeding is a predictor of possible enlargement of hematoma, providing clinician with valid management decisions. We report unusual MR imaging features of contrast extravasation in hyperacute ICH in three patients: Case 1 with hypertension revealed dual foci of contrast extravasation, one in right basal ganglia and the other in left lateral ventricle, suggesting simultaneous bleeding of the two foci. Case 2 with presumed diagnosis of vasculitis showed relatively large area of contrast extravasation mimicking enhancing tumor or vascular lesion. Case 3 with hypertension showed the findings of active bleeding which was likely to occur during the time of MR imaging acquisition.