• Korean Journal of Radiology
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• v.19 no.6
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• pp.1053-1065
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• 2018

Objective: To evaluate the clinical impact of using registration software for ablative margin assessment on pre-radiofrequency ablation (RFA) magnetic resonance imaging (MRI) and post-RFA computed tomography (CT) compared with the conventional side-by-side MR-CT visual comparison. Materials and Methods: In this Institutional Review Board-approved prospective study, 68 patients with 88 hepatocellulcar carcinomas (HCCs) who had undergone pre-RFA MRI were enrolled. Informed consent was obtained from all patients. Pre-RFA MRI and post-RFA CT images were analyzed to evaluate the presence of a sufficient safety margin (${\geq}3mm$) in two separate sessions using either side-by-side visual comparison or non-rigid registration software. Patients with an insufficient ablative margin on either one or both methods underwent additional treatment depending on the technical feasibility and patient's condition. Then, ablative margins were re-assessed using both methods. Local tumor progression (LTP) rates were compared between the sufficient and insufficient margin groups in each method. Results: The two methods showed 14.8% (13/88) discordance in estimating sufficient ablative margins. On registration software-assisted inspection, patients with insufficient ablative margins showed a significantly higher 5-year LTP rate than those with sufficient ablative margins (66.7% vs. 27.0%, p = 0.004). However, classification by visual inspection alone did not reveal a significant difference in 5-year LTP between the two groups (28.6% vs. 30.5%, p = 0.79). Conclusion: Registration software provided better ablative margin assessment than did visual inspection in patients with HCCs who had undergone pre-RFA MRI and post-RFA CT for prediction of LTP after RFA and may provide more precise risk stratification of those who are treated with RFA.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.234-237
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• 2003

The Korean housing supply have been provided by the Pre-construction sales system. The Pre-construction sales system contributed to large housing supply. But it followed by the market anomaly. Along the housing market is changing to tile market for consumers, it requires new policy and regulations. This market changes and needs to modify the policy make a discussion about introducing the Post-construction sales system. it concerns to change the time to sale. This paper analyzes the present feasibility study and makes a tool to predict construction cashflow considering changed sales point. The sales timing leads to decide the amount of financial costs in the construction project and that cost affects to the feasibility. The accurate cashflow prediction is required for a successful apartment construction delivery.

• Physical Therapy Korea
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• v.19 no.1
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• pp.86-93
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• 2012

The purpose of this study was to assess the feasibility of task-oriented arm training for chronic hemiparetic stroke patients. The experimental design in this study was the pre-test and post-test with control group for 4-week intervention. Thirty patients with chronic hemiparetic stroke were recruited from 2 rehabilitation units. The subjects were divided randomly into experimental and control groups. The experimental group conducted task-oriented approach, involving 3 subparts of upper extremity activities, and the control group involved in the general upper extremity exercises. Functional movements of the upper extremities were assessed using clinical measures, including the Fugl-Meyer Assessment-Upper Extremity Section, Box and Block Test, and Action Research Arm Test. The score of Fugl-Meyer Assessment showed greater increases in the experimental group than in the control group after training. The improvement in Box and Block Test between pre-test and post-test measurements was significantly greater after task-oriented arm training compared to general upper extremity exercises. Action Research Arm Test scores also improved after task-oriented arm training compared to exercises in the control group. The task-oriented arm training improves the gross and fine motor activities and encouraging the use of the paretic arm through activity dependent intervention expedites the recovery of functional activities in the upper extremities for chronic hemiparetic stroke.

• New & Renewable Energy
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• v.5 no.3
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• pp.40-48
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• 2009

Recovered heat has been considered as a renewable energy in Europe since 2008 because its great effect on energy saving and carbon decreasing in plant process. Energy saving and decreasing green gas are critical issue today, so various technologies to save energy and decrease carbon dioxide in plant process have been applied to many industrial area. In this paper, the feasibility of condenser heat recovery by heat pump in power plant for district heating and fuel line preheating were reviewed by verifying energy (heat) balance and mass balance of power plant model. Some ways to compose proper system to recover heat of condenser are suggested and their possibilities are also reviewed. Limitations on heat recovery in power plant are also reviewed. The results are verified by calculating input/output energy based on actual performance test data of Taean Thermal Power Plant in Korea. There is noticeable improvement of plant performance in some cases which demand low temperature (<100 C) heat like distrcit heating, fuel line heating, and so forth.

• Korean Journal of Agricultural Science
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• v.30 no.1
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• pp.89-101
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• 2003

For the pre-feasibility study and project evaluation, the discount rate or cutoff rate should be given by the government authority. To get the Benefit/Cost Ratio, NPV(Net Present Value) and IRR(Internal Rate of Return) of the public investment projects, the pertinent and realistic discount rate should be determined to be suitable to the present time period. The cut-off rates in Korea were equivalent to 15% in 1970's, 10% in 1980's and 8% in 1990's. The prevailing rate of discount as 8% is considered not to be suitable for the 2000's public project appraisal considering the present interest rates on deposit and national bonds. To determine the socio-economic feasibility of the public projects, the IRR should be bigger than the present cutoff rate. When we still use the high old rate of discount, the analytical results of project appraisal will show always economically unfeasible. Therefore the new rate of discount suitable for present time should be determined by the government. The public projects to be implemented in 2000 year onward are recommended to be adapted 5% of cutoff rate for the project appraisal and evaluation according to the results of reviewing the tendency of discount rates and market rates of interest in Korea.

• Journal of Hydrogen and New Energy
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• v.29 no.1
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• pp.124-129
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• 2018

Methane is the cleanest fuel and supplies by many distributed type: liquefaction natural gas (LNG), compressed natural gas (CNG), and pipeline natural gas (PNG). Natural gas is mainly composed by methane and has been discovered in the oil and gas fields. Coal bed methane (CBM) is also one of them which reserved in coalbed. This significant new energy sources has emerge to convert an energy source, hydrogen and hydrogen-driven chemicals. For this CBM, this paper was written to analyze the geological analysis and reserves in Mongolian Tavan Tolgoi CBM coal mine and to examine the application field. This paper is mainly a preliminary feasibility report analyzing the business of Tavan Tolgoi CBM and its exploitable gas.

• Korean Journal of Radiology
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• v.23 no.10
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• pp.949-958
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• 2022

Objective: To investigate the feasibility of using a deep learning-based analysis of auscultation data to predict significant stenosis of arteriovenous fistulas (AVF) in patients undergoing hemodialysis requiring percutaneous transluminal angioplasty (PTA). Materials and Methods: Forty patients (24 male and 16 female; median age, 62.5 years) with dysfunctional native AVF were prospectively recruited. Digital sounds from the AVF shunt were recorded using a wireless electronic stethoscope before (pre-PTA) and after PTA (post-PTA), and the audio files were subsequently converted to mel spectrograms, which were used to construct various deep convolutional neural network (DCNN) models (DenseNet201, EfficientNetB5, and ResNet50). The performance of these models for diagnosing ≥ 50% AVF stenosis was assessed and compared. The ground truth for the presence of ≥ 50% AVF stenosis was obtained using digital subtraction angiography. Gradient-weighted class activation mapping (Grad-CAM) was used to produce visual explanations for DCNN model decisions. Results: Eighty audio files were obtained from the 40 recruited patients and pooled for the study. Mel spectrograms of "pre-PTA" shunt sounds showed patterns corresponding to abnormal high-pitched bruits with systolic accentuation observed in patients with stenotic AVF. The ResNet50 and EfficientNetB5 models yielded an area under the receiver operating characteristic curve of 0.99 and 0.98, respectively, at optimized epochs for predicting ≥ 50% AVF stenosis. However, Grad-CAM heatmaps revealed that only ResNet50 highlighted areas relevant to AVF stenosis in the mel spectrogram. Conclusion: Mel spectrogram-based DCNN models, particularly ResNet50, successfully predicted the presence of significant AVF stenosis requiring PTA in this feasibility study and may potentially be used in AVF surveillance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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• pp.133-136
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• 2005

This study provides the method how to improve the productivity of a project using CM's constitutive methods. Construction industry in Korea was protected by the government and they have been grown with only their construction technology until today. It results Korean Construction is behind the advanced countries in terms of Engineering fields and construction management skills. This study compares the difference between the construction system of Korea and Europe and Asia. And then, it proposes the method how to compete with the other countries. which introduce the CM technique into the construction project in the beginning stage. Hopefully, this study is recognised as the basic strategy to improve the capability of Korean construction management.

• Journal of the Korean Institute of Educational Facilities
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• v.16 no.2
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• pp.37-45
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• 2009

The purpose of this study is to suggest the plan formation for university dormitory's living unit by the modular unit of the pre-fabricated architecture, Pursuing this, this study conducts the investigation of present domestic situation of prefabricated construction and practices plan formation for living unit concentrating on the dweller's satisfaction by solving the problems which hitherto constructed dormitory had, especially collapse of dweller's territoriality. Consequently, this study presents the feasibility of modular unit of present prefabricated construction as a new method of dormitory's living unit construction, and suggests the pertinent plan formation for the improvement of the dweller's territoriality.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.3
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• pp.1-6
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• 2012

This paper aims to suggest a validity analysis model that would be helpful for local governments considering u-City construction projects and a methodology for them to promote build-transfer-lease (BTL) u-City projects. This methodology mainly uses quantitative and qualitative analysis based on the Value For Money (VFM) designed by the Public and Private Infrastructure Investment Management Center (PIMAC) under the Korea Development Institute (KDI). BTL projects requires a large amount of capital and involves long-term investments. Therefore, multi-faceted validity analysis is required for the success of a project. This study will enumerate various factors to be considered in the pre-analysis of validity of BTL projects and suggest a methodology to verify them. A case study of a BTL project promoted by Ansan City assisted in designing this study in detail.