• Nuclear Engineering and Technology
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• v.26 no.2
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• pp.257-264
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• 1994

Experimental studies hate been peformed to investigate vapor explosion phenomena which may threaten the containment integrity during severe accidents in nuclear power plants. In this study, experimental equipment is constructed for vapor explosion experiments, and the vapor explosion experiments were conducted using water/R22. During the experiments, water/R22 interaction phenomena were observed using the high speed camera, and the explosion pressure and released mechanical energy were measured with pressure transducer and pressure relief tube. And the effects of some important parameters-hot liquid temperature, hot liquid injection velocity, hot liquid injection velocity, hot liquid injection time, and cold liquid depth-were investigated on the vapor explosion. Also, the experiment with grid was conducted to study reactor -vessel-lower-structure effect on fuel/coolant interaction. Water/R22 explosion conversion ratios were measured between 0.5∼1.6%.

• Journal of Life Science
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• v.21 no.1
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• pp.159-164
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• 2011

Microbial whole-cell biosensors can be excellent analytical tools for monitoring environmental pollutants. They are constructed by fusing reporter genes (e.g., lux, gfp or lacZ) to inducible regulatory genes which are responsive to the relevant pollutants, such as aromatic hydrocarbons and heavy metals. A large spectrum of microbial biosensors has been developed using recombinant DNA technology and applied in fields as diverse as environmental monitoring, medicine, food processing, agriculture, and defense. Furthermore, their sensitivity and target range could be improved by modification of regulatory genes. Recently, microbial biosensor cells have been immobilized on chips, optic fibers, and other platforms of high-throughput cell arrays. This paper reviews recent advances and future trends of genetically modified microbial biosensors used for monitoring of specific environmental pollutants.

• Korean Journal of Metals and Materials
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• v.49 no.1
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• pp.1-8
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• 2011

To measure the sensitivity of the hydrogen embrittlement from plated high strength bolts (SWCH18A, F11T), the bolt was stressed by a corresponding to the amount of tensile strain of 5% and 20%, and then the bolt developed a crack on the surface. The bolt that didn't have concentrated hydrogen, even though it was stressed by a corresponding the amount of tensile strain of 5% and 20%, no crack developed. However, the bolt that had concentrated hydrogen, developed cracks from the thread crest to the root. It is impossible to measure the hydrogen amount from plated high strength bolts using Hydrogen-Determinator, because of the limitation of the minimum sample size (about 1g as a mass or $5{\times}5{\times}5 mm^3$ as a volume). Therefore, the sensitivity of hydrogen embrittlement can be measured by observing the presence of cracks on the surface of plated high strength bolts which are stressed by a corresponding to the amount of tensile strain of 5% and 20%.

• Transactions of Materials Processing
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• v.31 no.4
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• pp.200-206
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• 2022

The finite element analysis is one of the representative methods for predicting the materials behavior for experiments that are difficult to perform empirically. Constitutive equations are essential for reducing computation time and sharing data because they enable finite element analysis simulations through simple formulae. However, it is difficult to derive accurate flow curves for all materials as most constitutive equations are not formulated based on their physical meaning. Also, even if the constitutive equation is a good representation of the flow curve to the experimental results, some fundamental issues remain unresolved, such as the effect of mesh size on the calculation results. In this study, a new constitutive equation was proposed to predict various materials by modifying the combined Swift-Voce model, and the calculation results with various mesh sizes were compared to better simulate the experimental results.

• Textile Coloration and Finishing
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• v.35 no.3
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• pp.179-187
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• 2023

In this study, we developed a microfiber-based flexible pressure sensor with high sensitivity and excellent skin breathability. A nonwoven fabric composed of microfibers was prepared by electrospinning, which resulted in excellent moisture permeability of the sensor (143 g∙m^-2∙h^-1). In particular, high-pressure sensitivity (0.36 kPa^-1) was achieved by introducing submicron structures on the microfiber surface by controlling the ambient humidity during electrospinning. The fabrication technology of the microfiber-based flexible pressure sensors reported in this study is expected to contribute to the commercialization of flexible pressure sensors applicable to long-term wearable health monitoring as well as virtual/augmented reality and electronic skin applications.

• Tuberculosis and Respiratory Diseases
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• v.42 no.5
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• pp.685-694
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• 1995

Introduction: Transthoracic fine needle aspiration biopsy(TNAB) has shown to be a resonably safe, simple, and accurate procedure in diagnosis of intrathoracic lung lesions. We reviewed the results of 1,005 TNAB of chest lesions performed on 930 patients with 20 or 22-gauze needles over a period of 10 years. Methods: From November 1983 to June 1995, 1,005 cases in 930 patients with an undiagnosed lung lesion underwent TNAB at the Hanyang University Hospital: 66% were men and 34% were women. Most of the patients were 40~60 years old and the youngest patient was 3 years of age. Result: 540 patients had various malignant chest lesions and 322 patients had benign pulmonary lesions. The diagnostic accuracy of TNAB was 96.1 percent in malignant diseases with one false positive result and 90.1% in benign diseases. A definitive diagnosis was not obtained in the remaining 68 patients. The most common diagnoses among 519 malignancy chest lesions with TNAB were the following: squamous cell lung carcinoma, 31.7%; adenocarcinoma, 24.7%; small cell lung carcinoma, 16.7%; metastatic cancer, 14.2%; large cell lung carcinoma, 6.2% and so on. Complications included pneumothorax in 12.3% necessitating chest tube drainage in 0.6%. Minor hemoptysis occurred in 3.6%. There was no death directly attributable to the procedure. Conclusion: We concluded that TNAB permits a direct approach to all kinds of localized lung lesions with a high degree of accuracy and without major complications.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.7 no.2
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• pp.77-83
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• 2014

Purpose: The purpose of current study was to evaluate the validity of the existing radiological classifications as a diagnostic modality for predicting characteristics of calcific deposition in calcific tendinitis of the shoulder joint. For that purpose, we determined the inter-observer reliability for evaluating diagnostic precisions of the classification and also evaluated diagnostic accuracy of predicting the toothpaste type calcific deposition. Materials and Methods: We performed retrospective study with total 26 patients surgically treated with calcific tendinitis of the shoulder joint from March 2010 to October 2013. Two independent observers reviewed preoperative radiographs of shoulder joints, and classified the characteristics of calcific depositions according to the criteria of Gartner, DePalma and Patte. Cohen's kappa were calculated for each classifications to evaluate inter-observer reliability. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio and diagnostic odds ratio were determined for type of calcific depositions with Gartner type III, DePalma type I, and Patte type II for predicting toothpaste type calcific deposition. Results: The values of Cohen's kappa were the highest in the classification of Patte, 0.62, and the values for the classifications of DePalma and Gartner were 0.56 and 0.36, respectively. The sensitivities for predicting toothpaste type calcific deposition in Gartner Type III, DePalma type I and Patte type II were 83.3%, 91.7%, and 58.3%, respectively. Specificities were 85.7% 50.0% and 64%, positive likelihood ratios were 5.833, 1.833 and 1.633, negative likelihood ratios were 0.194, 0.167 and 0.648, and diagnostic odds ratios were 30.00, 11.00 and 2.52, respectively. Conclusion: There were no radiologic classifications of calcific tendinitis which has both high precision and accuracy. Further studies with other diagnostic modalities such as ultrasonography are needed for predicting characteristics of calcific deposition in calcific tendinitis of the shoulder joint.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.25 no.4
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• pp.66-72
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• 1980

Forth soybean (Glycine max (L.) Merr.) cultivars were evaluated to determine the extent of crop injury caused by differential sensitivity of cultivars to two rates of alachlor, linuron, and metribuzin. Most cultivars were relatively tolerant of alachlor at 120 and 240g/10a and also linuron at 62.5 and 125g/10a. However, many cultivars were highly sensitive to metribuzin at 50 and 100g/10a. Some of the most sensitive cultivars were ‘Kyungnam 2’, ‘Toyosuzu’, ‘Noki 1’, ‘Iwade 2’, and ‘Hampton’. Metribuzin also showed a very narrow margin of safety to soybean cultivars.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.87-91
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• 1991

This study was performed to examine the mineral binding properties of total dietary fiber (TDF) and acid detergent fiber (ADF) from Job's tears (Yulmoo: Coix lachryma-jobi L. var. Ma-yuen Stapf.) bran. The endogenous Ca and Fe contents of dietary fiber extracted from Yulmoo bran were measured by atomic absorption spectrophotometer (AAS). Ca contents were 40, 118.6$\mu\textrm{g}$ Ca/g TDF and 131.6 $\mu\textrm{g}$ Ca/g ADF. Fe contents were 1,219.7 $\mu\textrm{g}$ Fe/g TDF and 277.5 $\mu\textrm{g}$ Fe/g ADF. The calcium binding capacities of dietary fiber at pH 5.0, 6.0, 7.0 were 50.77, 77.57, 86.64% for TDF, 40.27, 51.42, 40.90% for ADF, respectively. The iron binding capacity of dietary fiber at pH 5.0~7.0 was 95~97% for TDF and 85~95% for ADF.

• Parasites, Hosts and Diseases
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• v.21 no.2
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• pp.246-256
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• 1983

As epidemiological parameters of human paragonimiasis, the positive rates of intradermal test and the sputum/stool ekaminations have long been employed in population surveys. However, both the specificity of the intradermal test and the sensitivity of sputumjstool examination have been gradually declined as the endemicity was lowered; thus the gap between above two parameters widened. In such context, the development of a new epidemiologic parameter or tool which makes it possible to accurately discriminate the active paragonimiasis cases was necessary. In the present study, the detection rate of Paragonimus-speclac IgG antibody by micro-ELISA was evaluated as an indicator of epidemiologic status of human paragonimiasis in a population. A total of 4, 285 students and inhabitants living in Bukpyeong Myeon and Bukil Myeon, Haenam Gun, Jeonlanam Do was surveyed in October, 1983 by intradermal test first. Out of them, 244 cases (5.7%) were found positively reacted to VBS antigen of F. westermani. Out of 168 positive reactors, 7 cases (4.2%) were egg positive either by two times of sputum examination or by one stool examination. That indicated that only 0. 16% of total surveyed were confirmed as active paragonimiasis by egg detection. When sera collected from 239 positive reactors of Intradermal test were tested by micro-ELISA for their specific IgG antibody, 40 cases(16.7%) were found to be positive. All of 7 egg positive cases were again positive for specific IgG antibody. Among remaining 232 intradermal test positive cases, 33 cases were positive for IgG antibody. In contrast to those, none of 42 positive reactors to intradermal test for Cloncrchis and of 128 intradermal test negative cases showed positive for Paragcnimus-specIfic IgG antibody. The rate of specific IgG antibody as detected by micro-ELISA appeared to be increased with the wheal size of the intradermal test. When the wheal sixte was over 13mm in diameter, about 50% of them were positive for specific IgG antibody. Thirty-one specific antibody positive cases were clinically evaluated by laboratory examinations (repeated sputum examination, peripheral eosinophil count and chest roentgenogram) and by history taking. Out of them 24 cases were associated with one or more positive laboratory findings: thus considered as active paragonimiasis cases. Out of 7 lab. finding-free cases 3 revealed past history of typical paragonimiasis symptoms, suggesting that they were in chronic or in convalescent stages. The remaining 4 cases were considered as either mild or ectopic infection cases; the possibility of cross-reaction with other helminthiases could not be ruled out. From the above results, it was inferred that the detection of Paragonimus-specIfic IgG antibody by micro-ELISA was very much helpful in detecting the active cases as well as in proper evaluation of the endemicity of human paragonimiasis in a population. The convenience of mass haildling of sera in micro-ELISA was considered another superiority as an epidemiologic tool.