• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.4
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• pp.101-110
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• 2004

Flight and Qualification Models of Single Board Computer (SBC), called On-Board Computer (OBC), for HAUSAT-l picosatellite, which is scheduled to launch on September, 2004 by Russian "Dnepr" launch vehicle, have been developed. The OBC of HAUSAT-1 has been designed with some improved features compared to other picosatellites. A multifunctional controller and up-to-date SPI (Serial Peripheral Interface) and 1-Wire interface are implemented to simplify the harness routing and to minimize the mass and size of OBC. The improved fault-tolerant architecture design methodology is incorporated in the HAUSAT-1 OBC to protect against space radiation environment. The functions of the OBC were fully tested and verified by the Electrical Test Bed (ETB) model. This paper is also addressing the environmental test results, such as random vibration and thermal vacuum tests.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.352-363
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• 2014

The purpose of this study was to develop a proper teaching strategy to raise students' interests and creative problem-solving ability in science. And the result of applying this developed teaching strategy to elementary science lesson were compared with that of traditional science lesson. For comparison, two classes of $5^{th}$ grade in S elementary school in B city were selected. After pre-test, one class, experimental group, took a science lesson applying developed teaching strategy and other class, comparative group, took a traditional science lesson. After respective lesson, two classes did post test. The results of this study can be summarized as follows. First, IAAI(Interest-Activities-Attainment-Initiation) teaching strategy was developed. IAAI teaching strategy was composed of 4 stages which were (1)interest in science, (2)science experiment activities, (3)attainment to science knowledge, (4)initiation of creative thinking and 4 stages were progressed in serial order in science lesson. Second, after lessons, the experimental group achieved higher mark in the test of science academic achievement than the comparative group and it was statistically meaningful difference. Third, after lessons, the experimental group was more improved in science-related attitudes than the comparative group and it was statistically meaningful difference. Fourth, after the lesson, the experimental group was more improved than the comparative group in the creativity test and the difference was statistically meaningful.

• Journal of Korean Medicine Rehabilitation
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• v.30 no.2
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• pp.153-164
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• 2020

Objectives This study is designed to evaluate the safety of Soshihotang soft extract in healthy male volunteers. Methods 12 healthy male volunteers were recruited and this study was carried out by a single center. Laboratory test results, vital signs of the volunteers were collected to evaluate safety. According to registration order, the 12 subjects were allocated by serial number. To evaluate safety, blood samples were taken and vital signs were checked 4 times-screening, pre administration, post administration and follow up-during the whole trial. The incidence of all adverse effects are shown in percentage. The mean and standard deviation were used to to describe and summarize continuous data. To evalate the effectiveness of the intervention, data of blood tests was analyzed by Wilcoxon signed rank test or paired T-test (p<0.05). Results In the case of red blood cell, hemoglobin, hematocrit, neutrophils, protein, albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, γ-glutamyl transpeptidase values, the normality test result of the variable for the difference value before and after the dosing has a significance level <0.05. But most of values did not deviate from the normal range, and the deviation from the normal range could not be regarded as the significance associated with this clinical trial. And adverse event wasn't observed associated with the clinical trial drug. Conclusions Soshihotang soft extract were considered to be safe for healthy male volunteers.

• Korean Journal of Clinical Pharmacy
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• v.8 no.1
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• pp.19-22
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• 1998

Cefixime is an orally absorbed 3rd generation cephalosporin with a broad spectrum of activity against Gram-positive and Gram-negative bacteria and is highly resistant to $\beta-lactamase$ degradation. This study was carried out to evaluate the bioavailability of a new test drug of cefixime (100 mg/capsule) relative to the reference drug. The bioavailability was conducted on 20 healthy volunteers who received a single dose (400 mg) of the test and the reference drugs in the fasting state, in a randomized balanced 2-way crossover design. After dosing, serial blood samples were collected for a period of 12 hours. Plasma was analyzed for cefixime by a sensitive and validated HPLC assay. The major pharmacokinetic parameters $(AUC_{0-12hr},\;C_{max},\;T_{max})$ were calculated from the plasma concentration-time data of each volunteer. The $AUC_{0-12hr},\;C_{max}\;and\;T_{max}$ of the test drug were $36.91\pm11.85\;{\mu}g{\cdot}hr/ml,\;5.47\pm1.61\;{\mu}g/ml,\;and\;4.00\pm0.65\;hr,$ respectively, and those of the reference drug were $34.08\pm8.81\;{\mu}g{\cdot}hr/ml,\;5.25\pm1.40\;{\mu}g/ml,\;and\;4.20\pm0.62\;hr$, respectively. Mean differences of those parameters were 8.32, 4.29, and $4.76\%$, respectively, and the least significant differences at $\alpha$=0.05 for $AUC_{0-12hr},\;C_{max},\;T_{max}$ were 16.02, 13.78, and $11.76\%$, respectively. In conclusion, the test drug was bioequivalent with the reference drug.

• Journal of the Korean Society of Radiology
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• v.82 no.2
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• pp.359-370
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• 2021

Purpose To analyze the findings and serial changes in chest CT lesions in 123 symptomatic patients with coronavirus disease 2019 (COVID-19). Materials and Methods From February 19 to April 7, 2020, a total of 123 confirmed COVID-19 patients (male, 44; female, 79; mean age, 59.2 ± 18.6) were enrolled in this retrospective study. A total of 234 CT scans were reviewed for the following patterns: acute alveolar insult (AAI) patterns: ground-glass opacity (GGO), crazy-paving appearance, mixed pattern, and consolidation; organizing pneumonia (OP) patterns: perilobular patterns, band opacity, curvilinear opacity, reversed halo opacity, and small nodular consolidation; resolving patterns: pure GGO, remnant curvilinear, small nodular consolidation, and serial changes of lung abnormalities. We compared the proportions of AAI pattern, OP pattern, or resolving pattern with time progression and analyzed the association between the patterns and disease severity using Pearson chi-square and Fisher's exact test. Results Predominant CT patterns were AAI pattern (87%) in the early hospital period group (0-10 days, after the onset of symptoms), OP pattern (45.7%) in the later hospital period group (after 10 days), and resolving pattern in discharge and follow-up group (47.2% and 84.8%, respectively). The difference in the proportions of predominant CT patterns with time progression was statistically significant (p < 0.001, Pearson's chi-square test). No statistically significant association was observed between the patterns and disease severity (p = 0.055, Fisher's exact test). No fibrous changes in the lesions were observed on follow-up CT scans. Conclusion The serial CT scans of COVID-19 patients showed the spectrum of COVID pneumonia CT manifestations as different phases of lung injury and repair.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.74-79
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• 2019

The military vehicle produces electric power through an engine-integrated serial hybrid generator that is connected to the engine and does not have a separate generator installation space. However, depending on the mechanical characteristics of the connection between the generator and the engine, iron oxide for internal rusting and lubrication grew scattered. The iron oxide is adhered to the starter to deteriorate the starting performance, and there is a problem that the noise of the leg due to wear of the gear is increased. To solve this problem, the connection spline material and the surface treatment of the engine were improved and the shape was changed to a grease sealing type to prevent the generation of iron oxide inside. As the shape of the generator connector composing the shafting system was changed, the integrity of the structure was confirmed through the torsional endurance test. In addition, through the actual vehicle load test, it was verified that no corrosion occurred during the target life span without internal corrosion. It was confirmed that the anti-scattering structure of the grease effectively suppresses the generation of iron oxide, thereby reducing the noise generated from the generator. In this paper, we propose a fundamental solution to the degradation of the starter and the noise generation by preventing the back corrosion caused by the serial hybrid generator installed between the engine and the transmission.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.2
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• pp.156-163
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• 2008

Luminescent bacterial toxicity test was first introduced in the early 1980s, registered as international standard method in 1998 and now widely used as a common toxicity test method. This toxicity test uses luminescent bacterium, Vibrio fischeri, originated from marine environment as a test organism. The degree of toxicity can be evaluated from the comparison of luminescent emission intensity between control and treatment groups to toxicants and materials from various environmental matrix for 30 min. This test can be carried out by using commercial products and its results are sensitive and precise. This research is on the feasibility of adopting luminescent bacterial test as a domestic standard test protocol. Using commercial products, a series of experiments were conducted to identify the precision and accuracy of injection volume and light emission, and to evaluate concentration-response relationship between chemical concentrations and light emissions. Also, the feasibility of the application to environmental media and quality assurance/quality control were checked. The results of serial toxicity tests revealed that the preliminary luminescent bacterial toxicity test was robust and suitable as a standard method.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.36C no.2
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• pp.14-25
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• 1999

The IEEE standard 1149.1, which was proposed to increase the observability and the controllability in I/O pins, makes it possible the board level testing. In the boundary-scan environments, many shift operations are required due to their serial nature. This increases the test application time and the test application costs. To reduce the test application time, the method based on the parallel opereational multiple scan paths was proposed, but this requires the additional I/O pins and the internal wires. Moreover, it is difficult to make the designs in conformity to the IEEE standard 1149.1 since the standard does not support the parallel operation of data shifts on the scan paths. In this paper, the multiple scan path access algorithm which controls two scan paths simultaneously with one test bus is proposed. Based on the new algorithm, the new algorithm, the new board level BIST architecture which has a relatively small area overhead is developed. The new BIST architecture can reduce the test application time since it can shift the test patterns and the test responses of two scan paths at a time. In addition, it can reduce the costs for the test pattern generation and the test response analysis.

• Korean Journal of Veterinary Research
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• v.27 no.2
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• pp.307-316
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• 1987

This study was conducted to identify Babesia sp. strain isolated from the imported beef cattle, Aberdeen-angus heifers, in J farm of Jangsu Prefecture, Cheon-buk Province of Korea, morphologically, etiologically and serologically. Babesia sp. strain was purely isolated through the serial blood passages of three generations against splenectomized calves and one generation of blood passage against non-splenectomized calf(intact calf) by inhibiting the appearance of Theileria sergenti in the blood stream by means of injection of 20% oil pamaquine intramuscularly. In the splenectomized calves, the parasite multiplied markedly in blood stream soon after inoculation and parasitaemia was much severe. An elevated body temperature, anorexia, severe anaemia and icterus were observed clinically. Of three splenectomized calves, two were affected with haemoglobinuria and died. But in the non-splenectomized calf the clinical signs and parasitaemia were very mild. The means of the incubation period, the highest parasitaemia, the highest body temperature and the lowest PCV were 3.5 days, 41.1%, ${42^{\circ}C}$ and 9%, respectively, in the splenectomized calves. In calf erythrocytes Babesia sp. protozoa were polymorphic showing the round, oval, ameboid, piriform and paired piriform etc. The sizes of protozoa were $2.51{\sim}3.91{\times}1.32{\sim}2.19{{\mu}m}$ ($3.20{\times}1.60{\mu}m$). Serologically the isolated Babesia sp. were compared with other parasites, B. ovata, B. bigemina, B. bovis, T. sergenti, A. marginale and A. centrale by using the complement fixation(CF) test. As a result, the antibody titer between the homologous species were high. It was two tubes or more in the CF test. From the results obtained above the pure isolated Babesia species was identical with Babesia ovata Minami and Ishihara, 1980.

• Korean Journal of Environmental Biology
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• v.25 no.3
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• pp.267-272
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• 2007

Microorganisms capable of degrading poly(butylene succinate-co-butylene adipate) (PBSA) were isolated from 40 soil samples such as landfill site soil, cultivating soil and activated sludge soil from 20 different sites in Korea by using the enrichment culture and the clear zone test at $37^{\circ}C$. Based on the 16S rDNA sequences, the isolated bacterium was identified to be Streptomyces sp. PBSA-1. Morphological and cultural characteristics were employed for the identification of the isolated fungi and they were proved to be Aspergillus fumigatus PBSA-2 and Aspergillus fumigatus PBSA-3. The PBSA degradation activity of the isolated microorganisms was enhanced through the serial acclimation in PBSA plate medium. The PBSA degrading microorganisms appeared to be highly active for the PBSA degradation in that 83% of PBSA was degraded by Streptomyces sp. PBSA-l, and 65% and 75% of PBSA was mineralized by A. fumigatus PBSA2 and A. fumigatus PBSA-3 respectively during 40 days of the modified Sturm test.