• Journal of Bio-Environment Control
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• v.12 no.3
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• pp.107-113
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• 2003

This study was carried out to improve the performance of pre-developed heat recovery devices attached to exhaust-gas flue connected to combustion chamber of greenhouse heating system. Four different units were compared in the aspect of heat recovery performance; A-, B-, and C-types are exactly the same with the old ones reported in previous studies. D-type newly developed in this experiment is mainly different with the old ones in its heat exchange area and tube thickness. But airflow direction(U-turn) and pipe arrangement are similar with previous three types. The results are summarized as follows; 1. System performances in the aspect of heat recovery efficiency were estimated as 42.2% for A-type, 40.6% for B-type, 54.4% for C-type, and 69.2% for D-type. 2. There was not significant improvement of heat recovering efficiency between two different airflow directions inside the heat exchange system. But considering current technical conditions, straight air flow pattern has more advantage than hair-pin How pattern (U-turn f1ow). 3. The main factors influencing on heat recovery efficiency were presumably verified to be the total area of heat exchange surface, the thickness of ail-flow pipes, and the convective heat transfer coefficient influenced by airflow velocity under the conditions of allowable pipe durability and safety. 4. Desirable blower capacity for each type of heat recovery units were significantly different to each other. Therefore, the optimum airflow capacity should be determined by considering in economic aspect of electricity required together with the optimum heat recovery performance of given heat recovery systems.

• Journal of the Korean Wood Science and Technology
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• v.32 no.1
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• pp.28-34
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• 2004

This study was performed to evaluate the characteristics of the carboxymethylated substrate from high reactive autohydrolyzed cellulose (HRC) and those of commercial α-cellulose (CAC) and refiner mechanical pulp (RMP). Saccharification rates of HRC substrate were achieved over 70% with 12 hr hydrolysis, about 90% with 24 hr, and 99.5% with 72 hr. CMCase and avicelase activities of cellulase onozuka were 4.09 ㎛ G/mg·min and 14.0 ㎛ G/mg·min, respectively. There were no any significant changes in cellulase activities with this substrate. The saccharification rates of CAC and RMP were very low, 57% and 38% with 72 hr, respectively. Those lignin-zero autohydrolyzed substrates, HRC and CAC, were highly carboxymethylated at the high alkali concentration, near 30%, for 3 hr. reaction, and resulted in 1.13-1.15 of D.S., besides 0.85 of D.S. from RMP. Water solubilities of carboxymethylated substrates were increased with an increase of D.S., 98-98.5% from HRC and CAC and 31.5% from RMP. RMP which has low specific surface area showed lower water retention values, compared to high values of 435 and 321% from CAC and HRC, respectively. There were no direct relationship between surface area and swelling ratio of the substrates.

• Journal of Life Science
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• v.24 no.10
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• pp.1070-1077
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• 2014

In this study, the estrogen receptor agonist propyl pyrazole triol (PPT), which has high-affinity with the estrogen receptor alpha, was subcutaneously injected into adult male mice every 2 days for 8, 16 and 24 days, after which histological changes in accessory genital glands, including the prostate and seminal vesicle, and the liver were observed. The body and genital gland weights decreased in the PPT group relative to those of the control group. However, the liver weight was two times greater in the PPT group. The luminal area of the prostate and seminal vesicle organs was lower in the PPT group, and the epithelial cell height of the prostate was increased relative to that of the control. There were many secretory vacuoles in the supranuclear cytoplasm of epithelial cells in the seminal vesicles of the control group, but these were not observed in the PPT group. The short sinusoidal diameter of the liver was 147.0%, 198.7%, and 223.3% greater in the PPT group than in the control group after 8, 16, and 24 days of treatment, respectively. These results suggest that PPT administration affected the reproductive organs and the liver and that the histological changes increased in accordance with a rise in the concentration of PPT. Overall, the PPT treatment caused changes in the epithelial cell height and resulted in atrophy of the luminal area of the prostate, leading to altered fertility. The sinusoidal diameter of the liver dramatically increased in response to the administration of PPT, increasing the liver weight.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.1
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• pp.91-102
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• 2020

According to the Korea Radioactive Waste Agency's (KORAD's) medium and low level radioactive waste management implementation plan, the Domestic 3rd Step Landfill Disposal Facility has planned to accept a total of 104,000 drums (2 trenches) of very low level radioactive waste (VLLW), from the decommissioning site from April 2019 - February 2026 (total budget: 224.6 billion Won). Subsequently, 260,000 drums (5 trenches) will be disposed in a 34,076 ㎡. Accordingly, KORAD is preparing a waste acceptance criteria (WAC) for this facility. Every disposal facility for VLLW in other countries such as France and Spain, operate their WAC for each VLLW facility with a reasonable application approach, This, paper focuses on analyzing the WAC conditions in VLLW sites in the USA and discusses whether these can be met in domestic VLLW WAC. It also helps in the preparation of WAC for the 3rd Step Landfill Disposal Site in Gyeongju, since the USA has prior experience on decommissioning nuclear waste.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.04a
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• pp.169-170
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• 2010

Ulsan Port is in the situation which the harbour limit and anchorages are less narrow than other trading ports and the occurrence probability of marine accidents is high due to heavy marine traffic Especially, the shortage of anchorages will become worse in case that the number of inbound and outbound vessels increases according to the development of Ulsan New Port. We will find and suggest the plan to enlarge the harbour limit essentially needed to expand anchorages in this research The reasonable type of harbour limit which is based on the survey by a group of experts, was determined after the decision of the range of harbour limit to accommodate the relevant anchorages.

• Journal of Korea Ship Safrty Technology Authority
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• s.37
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• pp.24-34
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• 2014

최근 몇 년간 국내 해양레저에 대한 관심 증가에 따라, 정부와 지자체의 해양레저산업에 대한 연구 지원 및 마리나 구축 사업 수행 등 해양레저 수요를 수용할 수 있도록 장비 및 시설 확보를 위하여 다양한 방면으로 노력이 한창이다. 그러나 아직까지 국내의 해양레저를 위한 시설 구축은 진행단계이다. 전국적으로 마리나 구축을 위한 작업이 한창이며, 이미 구축된 마리나에서 요트를 계류할 경우 관리하는데 드는 비용이 만만치 않아 사용자에겐 부담이 크다. 세일링 요트의 경우 span이 큰 모노킬이 부착되어있으므로 마리나 혹은 육상계류시설을 이용하지 않을시 모노킬이 파손될 위험이 있다. 본 연구에서는 서해안의 해양레저 대중화를 위해 누구나 안전하게 세일링을 즐길 수 있고, 두 개의 킬로 선체를 지지하여 육상 및 갯벌에서도 선체가 기울지 않고 설 수 있는 트윈킬 요트를 개발하여 보급하고자 한다. 기존 세일링 요트중 성능이 좋은 편인 야마하에서 제작한 블루워터21의 선형을 활용하였고 트윈킬은 블루워터21 모노킬의 면적 및 무게중심 등을 분석하여 개발하였다. 트윈킬 요트의 경우 모노킬 요트보다는 저항성능이 불리할 것으로 예상되므로 모형시험을 수행하였으며, 그 결과 모노킬과 트윈킬의 저항성능에 대한 차이가 예상보다 크지 않음을 확인하였다.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.3
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• pp.86-93
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• 2008

The multi-mode terminal modem which is capable of accommodating a variety of wireless communication standards needs versatile arithmetic units for processing a variety of word lengths and wide range of data rates. Since the target hardware is usually designed to meet the required highest performance, it is often wasteful in power consumption especially when low rate data processing cases. Thus, a speed and power adaptability of the arithmetic unit is a desirable feature for the wireless applications. In this paper, we propose a power efficient versatile adder architecture with carry skip logic as a basic building block constructed in hierarchical manner. The validity of the architecture is shown with respect to size, performance, and power efficiency in diverse operating modes.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.171-175
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• 2005

The purpose of this study was to suggest the Support and Infill system for 126.6m$^2$-sized housing unit which meets residents' variety. The subjects were 100 housewives who lived in 126.6m$^2$-sized housing unit in the apartment complex, Busan. The data was collected by using model and questionnaire. The model was made to be same as the current 126.6m$^2$-sized floor plan. The residents preferred the flexible housing unit apartment complex. Also, the residents' needs for floor plan of housing unit were various. Therefore, the development of flexible housing unit is needed. On the basis of these findings, the support and infill system for 126.6m$^2$-sized housing unit was suggested.

• PNF and Movement
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• v.17 no.1
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• pp.103-109
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• 2019

Purpose: The purpose of this study was to investigate the effect of temporary visual block existence and nonexistence on the change in foot pressure and foot area in stroke patients. Methods: Sixty-one chronic stroke patients volunteered to participate in the study. Foot pressure and foot area were measured using the Biorescue system. The subject maintain a comfortable standing position on the pressure-measuring plate one meter away from the computer. The sequence of the visual variation data while standing on the measuring plate was collected randomly. The data were collected with three repetitions and used the five-second measuring values except the first second and the last second according to each visual condition. All data were analyzed using SPSS version 21.0. The significance level for the statistical inspection was set as 0.05. Results: The comparison between the visual existence and nonexistence status showed statistically significant effects on foot pressure and foot area. The visual nonexistence status showed more improvement in foot pressure symmetry and area than visual existence status. Conclusion: This study shows that the foot pressure and foot area for the chronic stroke patients changed according to the visual states. It is predicted that these data will be used in rehabilitation training programs and to present temporary changes in visual status for stroke patients.

• Journal of Animal Environmental Science
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• v.18 no.3
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• pp.235-246
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• 2012

Reusing livestock manure have various advantages in securing soil organic resources. In this study, the N-loading and recycling capacity assessment of animal manure was analyzed by comparing between the cultivated areas of crops and the amount of manure units that are generated from livestock manure. From this assessment, the possibility of recycling resources of livestock manure was evaluated. The amount generated of livestock manure in Gyeonggi-do were evaluated by applying the manure units to the number of livestock manure. The analysis of manure unit per ha shows that the N loading by MU is quite different by region. When it comes to nitrogen loading, the MU per ha of cultivated land in excess of the N-amount was the highest in the Gyeonggi-do province with 2.70 MU/ha, which is higher than the appropriate level. The Chungcheongnam-do province came next with 2.31 MU. So the recycling capacity assessment was carried out mainly based on areas of forage crops, rice that can be provided by recycling livestock manure. The recycling capacity ware highest in Jeollanam-do and Jeollabuk-do. In order to properly apply the livestock manure into organic resources, the seasonal situation that effects the nitrogen demands of crops along with the regional effects crop cultivation should be seriously analyzed. In addition, a system that can effectively produce and manage fertilizer should be established.