• Journal of Auto-vehicle Safety Association
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• v.16 no.1
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• pp.49-54
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• 2024

This paper provides an analysis of the experimental procedures and results to ensure the reliability of the system manufactured for testing the hydrogen permeability of a 175 L compressed hydrogen container for a hydrogen bus. Based on the hydrogen permeability standard of 6 cc/(h·L), it was injected into the permeability test chamber at 10% intervals, and the permeated hydrogen concentration according to the injected amount was measured and compared with the actual amount of hydrogen permeated. As a result of the experiment, the measured value represented 96.34% of the actual permeation amount, which can be used as basic data for the hydrogen bus vessel permeability test system being built in Korea.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.423-424
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• 2002

Amount of regulated emissions (CO, $NO_x$, HC), and emissions of some groups of organic substances (volatile hydrocarbons, polyaromatics, and aldehydes) were measured in the standard ECE 83 test on spark ignition engine of a passenger car. The influence of the engine oil composition (mineral or fully synthetic) was examined. For both engine oils, exhaust emissions were measured with fresh oil as well as used oil at the end of the oil drain interval. Unleaded petrol and CNG were used as fuels in all experiments performed. The main conclusion made from the tests is that polyaromatics is the only part of th ε exhaust emissions that was influenced with the nature of the engine oil. Effect on the other components of emissions (aldehydes and VOC) was negligible. Emissions of polyaromatics were almost twice higher for fresh mineral as for fresh fully synthetic oil. The amount of polyaromatics in the exhaust emissions increased slightly with mileage for fully synthetic and substantially more for mineral engine oil.

• Korean Journal of Digital Imaging in Medicine
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• v.3 no.1
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• pp.76-84
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• 1997

We tried to find any factor to reduce the exposure dose with ST-VA type generator which has the higher exposure dose. The guideline recommended by the provisions of IAEA regulation is being used at the time of radiation exposure and almost of those equipments used for this study had less amount of doses than those in the guideline. The FCR may be possible to decrease a certain amount of dose with effective applications of it's automatic image compensation utilities and the verifying function in PACS. Next time, it is required to add a great number of hospitals for wide range of studios and measurements, and make standard exposure Control table which will bing in practice, material decrease of dose volumes when radiation exposure.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.313-314
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• 2006

Indicating product quantity by real time can be benefit both worker and management. Worker can compare real product quantity with its target and can adjust working speed to match with goal. Therefore, so called JPH equipment developed to indicate target quantity of product. As a main processor PIC16F877 was used and FND display were used to indicate current time, elapsed time, JPH value and target amount of product. Values like JPH and starting time, etc. are can easily be set by $4{\times}4$ numeric keypad and display datum likes target amount of product, current time and elapsed time, etc are displayed on FND by RS232 serial transmit. The operation of JPH equipment are tested and verified through long term test and are proved acting properly on working conditions.

• Journal of Internet Computing and Services
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• v.9 no.5
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• pp.185-193
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• 2008

An MTBF(mean time between failures) of large scale parallel systems is known to be only an order of several hours, and large computations sometimes result in a waste of huge amount of CPU time, However. the MPI(Message Passing Interface), a de facto standard for message passing parallel programming, suggests no possibility to handle such a problem. In this paper, we propose an application-level fault tolerant computation system, purely on the basis of the current MPI standard without using any non-standard fault tolerant MPI library, that can be used for general scientific synchronous parallel computation.

• Journal of the korean academy of Pediatric Dentistry
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• v.8 no.1
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• pp.119-125
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• 1981

The Purpose of this study was to evaluate the effect of frozen slab mixing technique on physical property of zinc phosphate cement used in Korea. Standard consistency, setting time, film thickness, solubility of cement prepared in frozen slab and room temperature slab were tested. The obtained results were as follows. 1. Amount of powder required for standard-consistency for all cements tested could be increased. 2. Setting time for all cements tested could be decreased. 3. No significant difference in film thickness. 4. Solubility for all cements tested could be decreased.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.18 no.2
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• pp.115-121
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• 2008

In winter season, the survey was performed in three commercial office buildings in the metropolitan Seoul, Pusan, and Gwangju city. The purpose of the survey was to evaluate the effectiveness of ventilation for offices in commercial buildings. The data were compared to standard of applicable to the indoor ventilation in office. The results indicated that the most commercial office buildings used the air handing unit and fan coil unit as HVAC system, and the intake amount of fresh outdoor air were very inadequate to compared to the ASHRAE standard value of $0.57\;m^3/min/person$. Also the surveyed all commercial office building used the HVAC system as a meas of controlling temperature for office indoor air. Ultimately, these results presented that there were possibility of evoking indoor air quality problems by the insufficient ventilation.

• Fisheries and Aquatic Sciences
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• v.25 no.5
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• pp.264-275
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• 2022

A non-destructive environmental DNA protocol for the genetic analysis of sea cucumber (Apostichopus japonicus) resources DNA was established. Among the several commercial DNA extraction kits, the DNeasy^® Plant Mini Kit was selected as the best choice to obtain the high-quality genomic DNAs from the mucous sea cucumber. As the temperature and incubation time increased, the amount of extracted environmental DNA was also large, but it was judged that the increased amount did not affect as much as 2-3 times. Therefore, these conditions were not considered to be the main factors to consider in actual environmental DNA extraction. However, the amount of seawater relative to the size of the sample was judged as a major consideration, and a sufficient amount of environmental DNA for analysis was secured when stored within 1 min while stirring the volume of seawater corresponding to the total sea cucumber weight (g). In securing the environmental DNA of sea cucumbers, the mortality rate of sea cucumbers in all experiments was 0, and it was judged that the effects of sea cucumbers were not significant through this treatment. Through the results of this study, sea cucumber DNA research, which has been conducted in a destructive method, can be conducted non-destructively through environmental DNA analysis. Through this study, we have secured a standard protocol that can successfully extract the sea cucumber DNA through environmental DNA. It is not only excellent in terms of time and cost of traditional DNA analysis method currently used, but it is completely non-destructive in the ecosystem of the survey area. It is believed that the system can be transformed in a way that does not affect it. However, it is thought that various standard protocols should be established considering the characteristics of each type.

• Journal of Chest Surgery
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• v.27 no.10
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• pp.833-837
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• 1994

Lung contusion due to blunt chest trauma is the most common lung injury and correlated with the clinical course and prognosis. Its diagnosis by CT[Computerized Tomogram] gives a more clear and understandable three dimensional view, by which we are able to measure the volume of the contused and entire lung. Other variables are arterial blood gas, number of rib fracture, presence of hemopneumothorax, sternal fracture and clavicle fracture, number of associated non-thoracic injuries, ventilator time and presence of pulmonary complication. Percentage[%] of lung contusion are expressed as mean $\pm$ standard deviation and data analysis was performed by means of multivariate repeated measures analysis of variance to detect significant differences in variables between positive thoracic injury group and negative group. The paired t-test was used. Differences of percentage of lung contusion between groups were assessed by one-way analysis of variance. Simple linear regression was used to perform correlation analysis in the number of rib fracture and ventilator time. A p value less than 0.05 was considered statistically significant. Pneumothorax and the number of associated other injuries affect the amount of lung contusion and pulmonary complication group has more contused lung volume. Arterial blood gas study shows no correlation with the amount of lung contusion statistically. The number of rib fracture correlated with the amount of lung contusion, which also correlated with ventilator time[r=0.56, p<0.05]. In conclusion, quantitative anlysis of lung contusion by CT predicts the clinical course and treatment such as ventilator care.

• Journal of KIBIM
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• v.3 no.4
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• pp.1-10
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• 2013

In order to boost productivity and efficiency of architectural design, architect accumulates materials and details which are repeatedly used. According as introduction and application of BIM (Building Information Modeling) have proliferated, a number of data are being produced. BIM data constructed in a stage of architectural design reduces repetitive works of design and can be used in estimate and construction, maintenance. BIM library gathered these data are able to enhance participants collaboration and design improvement. Library is a vital factor in BIM and a number of libraries are needed as BIM introduction and application have proliferated in architecture industry. However, BIM Library establishment and related research development are incomplete. And specific standard setting and institutional environment for BIM library building have not been achieved. As such a vast amount of information are generated but there is no systematic plan and reuse frequency is low. So it is necessary to build system for effective data sharing and operation management. In this study, through establishment of BIM standard system and construction of management environmental system, it has an object in view for developing framework which can efficiently manage various libraries happened in BIM architectural design field.