• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2002.05a
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• pp.191-197
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• 2002

The motion of a floating OWC chamber in waves is studied taking account of fluctuating.air pressure in the air chamber. An atmospheric pressure drop occurs across the upper opening of the chamber which causes not only hydrodynamic but also pneumatic added mass and damping forces to the floating chamber. A velocity potential in the water due to the free surface oscillating pressure patch is added to the conventional radiation-diffraction potential problem. The potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine Green function while the outer problem with the Kelvin Green function. The two integral equations are solved simultaneously by making use of a matching boundary condition at the lower opening of the chamber to the outer water region. The chamber motion in the frequency domain is calculated for various values of parameters related to the atmospheric pressure drop. The present methods can also be used for the analysis of air-cushion vehicle motion as well as for the design oj a floating owe wave energy absorber.

• Proceedings of the KSRS Conference
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• v.1
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• pp.446-449
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• 2006

It is backscattering of solar radiation by water body that makes ocean color observable from above, either by airplanes or satellites. Given the very low direct contribution to backscattering by phytoplankton cells, it is curious why the retrieval of phytoplankton concentration from remotely observed ocean color is evidently successful. From semianalytical bio-optical models, a dataset is created of spectral absorption, scattering and backscattering coefficients as a function of chlorophyll concentration. Four scenarios are considered, 1) only molecular and no particle scattering, 2) random particle backscattering uncorrelated with chlorophyll concentration, 3) constrained random particle scattering with known backscattering ratio, and 4) constrained random scattering with random backscattering ratio. Scenario 1 only introduces moderate errors of -20% - 90%. And for scenarios 3 and 4, the errors are largely within 30% and 100%. Scenario 2 introduces the largest errors, with the retrieved chlorophyll concentration virtually uncorrelated with the true values, implying the backscattering must somehow be related to the trophic state. The results of the study suggested These 3 cases confirmed that while it is the absorption by phytoplankton that in large part decides the accuracy of chlorophyll concentration retrieval, for the success of monitoring of global ocean primary productivity we have to improve our knowledge on particle backscattering.

• Korean Journal of Veterinary Research
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• v.19 no.1
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• pp.1-8
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• 1979

Detailed human gross anatomic structures have been characterized. No similar data are available in nonhuman primate species in spite of close phylogenic similarity found between man and nonhuman primates. The ever increasing incidence of lung cancer and air pollution related respiratory ailments found in man emphasizes the need for an ideal animal model for studying pathogenesis of these various human pulmonary diseases. Thus, detailed investigation of pulmonary structures found in various species of nonhuman primates is warranted. For determining primate gross pulmonary anatomic structure, published works concerning the number of tracheal cartilage, angle of tracheal bifurcation, caliber of trachea, lung lobe and bifurcation position of trachea recorded for several species of nonhuman pimates, were reviewed. Limited information is available concerning the number of tracheal cartilage, width of tracheal cartilage, angle of bronchus, caliber of trachea and bronchus, and the bifurcation position of the trachea including the length of bronchus on nonhuman primates. Since scanty data have been gathered with no specific reference to their age, sex and body weight, they have no comparative values.

• Fashion & Textile Research Journal
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• v.13 no.4
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• pp.624-634
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• 2011

The purpose of this study is to develop the pattern of safety clothes used at flat or mountainous areas and to identify the pattern of safety clothes by conducting experimental evaluation of virtual wear. Three subjects were selected, based on fire fighters' physical constitution. A prototype design for safety clothing was determined after in-depth interviewing of professionals and surveying of Forest service staff and related agency. Wearing test should be carried out in the order of pattern making, virtual and real wearing evaluation. For data analysis, technical statistical values should be obtained by using body measurements of subject, frequency analysis and T-test. The jacket is designed to have a front extension and the entire length of clothing enough for wearer to put on it over ordinary shirts or sweater. The collar of jacket is of round type. Cyber reality enables to identify the movement and activity of virtual fitting model and to find out errors or problems in safety clothing prior to on-the-spot wear test, thus raising the precision level of pattern. There was significant difference between real and virtual fit preference. The results show that the virtual try-on system need the development of a specific style.

• Environmental Analysis Health and Toxicology
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• v.17 no.1
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• pp.81-93
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• 2002

There were no specific effects for test materials on Sprague-Dawiey (S.D.) rats in clinical symptoms, amounts of food intakes, weight changes, laboratory findings, and pathology after whole body 1, 1-Dichloro-1-fluoroethane (used as coolant, metal cleaner and solvents) exposure (0, 1,500, 3,000, and 6,000 ppm) for 13 weeks (6 hour/day, 5 days/week). However, the loss of capillary vessels in eyeball (pupil) was observed in a female rat among 6,000 ppm group. Though there was a tendency for MCHC (Mean Corpuscular Hemoglobin Concentration) in rat to be decreased (p<0.05), it was not regarded as abnormal because the values were within normal limits. In asthma-stimulation related evaluations. there was also a tendency for inflammatory cell counts in bronchoalveolar lavages to be increased. But it had no statistical significance, and also no dependency on sex and the exposed concentration . Based on this result, the non observed effect level (NOEL) induced by 1, 1-Dichloro-1-fluoroethane inhalation was evaluated in groups with 3,000 ppm below (S.D. Rats, 13 weeks). Finally, it was concluded that the short term exposal of 1, 1-Dichloro-1-fluoroethane is not considered as a asthma stimulant by inhalation despite of some study limitations such as test animals use and short-term exposure.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1995.04a
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• pp.121-121
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• 1995

This study was conducted to examine novel Pt(II) complexes, (KHPC-002: [Pt(trans-1-dach) (DPPE)]. 2N0$_3$, KHPC-005: [Pt(cis-dach) (DPPE)] 2NO$_3$ and KHPC-006: [Pt(cis-dach) (DPPP)]. 2NO$_3$) for their acute toxicities. In male and female mice given a single intraperitoneal administration of KHPC-002, KHPC-005 and KHPC-006, we determined that LD$\_$50/ values of Pt(II) complexes were 295.5mg/kg(M), 350.4mg/kg(F) : KHPC-002, 596.5mg/kg(M), 674,8mg/kg(F): KHPC-005, 158.7mg/kg(M), 157.7mg/kg(F); KHPC-006, respectively. The signs of toxicity in mice observed fellowing the administration of these compounds included the followings: decreased mortor activity: abnormal gait: salviation, trasient decreased body weight. There were no treatment related specific changes in growth examination.

• Korean Journal of Occupational Health Nursing
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• v.10 no.1
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• pp.66-73
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• 2001

In health promotion program, the fear of gaining weight is often given as a reason for giving up smoking cessation by the participants. The purpose of this study is to compare drinking habit, exercise and BMI distribution according to smoking habits. The subjects of this study were 83 industrial workers in Gu-mi. Data collection was conducted from Sep. 18th to Sep. 24th 2000. The method was self-reported questionnaire survey, consisted of general characterisics, smoking habits and its relevant questions. The results are as follows : 1. Fifty-nine percents of the subjects were currently smoking. 2. Smoking habits were significantly related with drinking(p=.049). More smokers(81.6%) reported drinking habit than non-smokers(61.7%). 3. Forty-one point two percents of the non-smoker and 34.7% of the smoker perceived their body type as "fat". 4. The mean values of BMI were 22.0 in smokers with 1-9 cigarettes/day, 24.2 in 10-19 cigarettes/day smokers and 24.0 in smokers with over 20 cigarettes/day. There are no statistically significant differences in BMI among smoking habits. 5. BMI among different smoking habit groups was not significant different in age, drinking habit, exercise, and smoking habit.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.2
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• pp.149-155
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• 2013

For in-depth research of blood flow, it is important to create pulsating flow like the blood flow from heart beat. In this study, we developed a heart mimicking pulsatile pump and evaluated its performances. Main body of pump was produced using a piston pump, and its rpm and duty ratio was modulated by DC motor and encoder. To determine the part dimensions, principle stress theory and simple fluidic pressure analysis were used. The performance of pulsating pump was evaluated by comparing the pressure values and their deviations according to experimental variables. For the results, the output value of pressure followed the distribution of pulsating flow and its deviation was negligible. Through this study, we expect the established pulsating pump can be widely used in study of blood flow produce easy ways to related researchers.

• Journal of Korean Institute of Industrial Engineers
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• v.16 no.1
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• pp.67-81
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• 1990

Effectiveness of physical exercise in reducing work-related musculoskeletal stress was investigated. This was compared to the stress alleviation accomplished by using ergonomically designed work station. Tasks chosen for the study were data entry and file maintenance on the video display terminal (VDT). Three different measures, namely root-mean-square (RMS) values of electromyogram (EMG), subjective rating and task performance were used for the evaluation. Electromyograms were recorded from the neck, the left and right trapezius muscles in the shoulder region, and L2/L3 region of the back. Subjects rated discomfort levels for the same parts of their body. Task performance was measured by recording typing speed and errors. Each of the five subjects was tested for two days (8 hours/day) in two different work stations. These were the ergonomically designed adjustable work station and the fixed work station of traditional design with no adjustable features. Assigned physical exercises were performed for four minutes, every two hours during the breaks, by the subjects while working in the fixed work station. It was concluded that the physical exercise could be helpful in reducing musculoskeletal stress as effectively as the ergonomic design of the VDT work station.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.1
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• pp.107-115
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• 2019

This research explores a historical trajectory of the Milwaukee Art Museum from its establishment to the third expansion over the last six decades. After established in 1957 by the architect, Eero Saarinen, this museum underwent three expansions led by three different architects including, David Kahler, Santiago Calatrava, and James Shields. Reasons for expanding the museum were varied. A lack of exhibition space, an absence of visual identity, and path interruption problem within urban contexts were the main factors of a series of expansion. Furthermore, this research points out that there are three issues in the process of the expansion. The first is connection issues between the downtown and the lakefront in which the museum has blocked the public flow. The second, there were controversies on the allocation of the expanded space among the main body of the decision including architects, curators, and stakeholders. The last one is relationships among architects. This is related to each architect's attitude toward the museum. Drawing on historical documents and interviews with the regional architects, I argue that the identity and values of the museum have changed over time through the expansions rather than having the invariable.