• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.157-165
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• 2020

Objective: The objective of this study was to compare the quality of dry-aged beef from cull Hanwoo cows slaughtered at 60 or 80 months old. Methods: A total of eight cull Hanwoo carcasses with a quality grade of 3 (low-grade) were selected and divided into two age groups: 63.5±2.5 months old (n = 4) and 87.8±4.5 months old (n = 4). Whole longissimus thoracis et lumborum from the 11th rib to the last lumbar vertebrae, including the back fat, was removed from the carcass at 24 h postmortem and aged for 50 days in darkness at a temperature of 2℃±1℃, a relative humidity of 85% and an air flow of 2 m/s. The sampling was performed aseptically after 0, 20, 24, 40, and 50 days of aging. Results: Regardless of the aging period, aging increased the lightness (p<0.05), redness (p<0.05) and yellowness (p<0.05) at initial blooming (90 min after slicing) and the overall acceptance (p<0.05). No further tenderization effect was found after 20 days of aging, but aging for 50 days significantly increased the lipid oxidation (p<0.05). The generation of aroma volatiles in the roast steak from aged samples was higher (p<0.05) than that of non-aged samples. No significant effect of age at slaughter was found on the color, pH, water-holding capacity, cooking loss, shear force value, bacterial counts, volatile basic nitrogen, consumer acceptance, lipid oxidation, fatty acid composition or aroma volatiles. Conclusion: The quality of dry-aged beef obtained from cull Hanwoo cows slaughtered at either 60 or 80 months old with similar quality grade was comparable and extending dry aging for more than 40 days is not recommended considering the costs and further lipid oxidation.

• The Journal of the Acoustical Society of Korea
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• v.32 no.6
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• pp.472-483
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• 2013

Actual maritime exercise for improving the capability of submarine sonar operator leads to a lot of cost and constraints. Sonar simulator maximizes the capability of sonar operator and training effect by solving these problems and simulating a realistic battlefield environment. In this study, a passive sonar simulator algorithm is suggested, where the simulator is divided into three modules: maneuvering module, noise source module, and sound propagation module. Maneuvering module is implemented in three-dimensional coordinate system and time interval is set as the rate of vessel changing course. Noise source module consists of target noise, ocean ambient noise, and self noise. Target noise is divided into modulated/unmodulated and narrowband/broadband signals as their frequency characteristics, and they are applied to ship radiated noise level depending on the vessel tonnage and velocity. Ocean ambient noise is simulated depending on the wind noise considering the waveguide effect and other ambient noise. Self noise is also simulated for flow noise and insertion loss of sonar-dome. The sound propagation module is based on ray propagation, where summation of amplitude, phase, and time delay for each eigen-ray is multiplied by target noise in the frequency domain. Finally, simulated results based on various scenarios are in good agreement with generated noise in the real ocean.

• Journal of Cadastre & Land InformatiX
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• v.44 no.2
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• pp.209-230
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• 2014

There are three forms of REITs company in Korea that was first introduced in 2002. Each REITs have been listed on the KRX, its characteristics are different, but it is classified as a REITs company in all events. REITs current methods are applied uniformly manner that does not reflect the characteristics of the individual. REITs some, that is not seen unlike legislative intent, it is delisted, such as generating an investment loss of investors. In this study it is an object of the invention from the point of view of REITs business validity, to draw up operational support aggressive plans of the scheme. By improving the PF assesment system, to improve the relevance of REIT business and presenting policy direction to the activation of REITs. Through the sophistication of real estate finance utilizing REITs, policy for proper investment of general investors REITs funds were listed with the smooth flow must be realized. The results of this study, it can be utilized as basic data for policy to reflect the real estate policy for activation of the indirect financial investments.

• The Korean Journal of Pain
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• v.7 no.2
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• pp.162-169
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• 1994

Blockade of cervicothoracic sympathetic ganglion (stellate ganglion controls pain on face, head, neck, shoulder, upper limbs, and upper chest, including their viscera and sympathetically maintained pain. This procedure also increases blood flow to the above areas and relieves hyperreactivity of sympathetic nervous system. Clinically, repeated stellate ganglion blocks with local anesthetic agent may become difficult with complications such as accidental intravascular or subdural injection, recurrent laryngeal nerve or bracheal plexus paralysis, pneumothorax and edema on injection site. Therefore, at times long-term cervicothoracic ganglion block with neurolytics is necessitated but its applications are prohibited by the critical structures surrounding ganglion. There are also few reports of neurolytic stellate ganglion block. This study was performed to observe the complications, gross changes of surrounding structures, and microscopic findings of ganglion cells after neurolytic block and to certify the possibility of clinical use of neruolytic stellate ganglion block. The unilateral superior cervical sympathetic ganglion of rabbit was blocked with absolute ethyl alcohol 0.4 ml at the level of cricoid cartilage. Normal ganglion was used as a control and 5 animals were sacrificed at each intervals of 7, 15 and 50 days after block. The results were as follows; 1) All experimental animals showed no specific changes of behavior, motor function. No necrotic tissues were present in the block area during the observation period. There were some gross scar tissues along the fascia of muscles surrounding the needle injection site, but gross atrophy of muscles or injured major vessels were not found. 2) Microscopically, structures of normal ganglion of rabbit were very similar to those of humans. Seven days after absolute ethyl achohol injection there were marked edema of ganglion cells and nuclei with irregular nuclear membrane. Some of the ganglion cells lost their nuclei and showed degenerative changes. Fifteen days after block, cell edema were decreased and loss of the Nissl's body was prominant. The ganglion cell structures looked close to normal but the cytoplasm and nucleus were generally contracted 50 days after block. These results suggest absolute ethyl alcohol injection on cervical sympathetic ganglion with above method mainly blocks pre- and post-synaptic fibers and the long-term neurolytic blockade of this ganglion may be possible in rabbits.

• Reproductive and Developmental Biology
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• v.32 no.1
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• pp.9-14
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• 2008

Efficient gene transfer into hematopoietic stem cells is a great tool for gene therapy of hematopoietic disease. Retrovirus have been extensively used for gene delivery and gene therapy. However, current in vitro gene transfer has some obstacles suck as induction of differentiation loss of self-renewal capacity, and down-regulation of homing efficiency for in vitro hematopoietic stem cells transplantation. To overcome these problems, we developed efficient in vitro retroviral transfer technique by direct intra-bone marrow injection (IBM). We identified effective retrovirus gene transfer in bone marrow hematopoietic cells in vitro. Two weeks after retrovirus transfer via IBM injection, we observed stable EGFP gene expression in bone marrow, lymph node, spleen, and liver cells. In addition, $6.4{\pm}2.7%$ of hematopoietic stem/progenitor cells were expressed EGFP transgene from flow cytometry analysis. Our results demonstrate that in vitro retrovirus gene transfer via IBM injection can provide a viable alternative to current or moo gene transfer approach.

• Journal of Preventive Medicine and Public Health
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• v.29 no.1 s.52
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• pp.43-50
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• 1996

We experienced a case of nephropathy in chronic lead poisoning. The patient was 43-year-old male who has been working in secondary lead smelting plant for 14 years. On admission, blood pressure was 160/90 mmHg and the others were non-specific. In past history, he received chelating agent administration for lead poisoning irregularly and medicated for gout, and the blood lead concentration was $180.0{\mu}g/dl$ on 2 months before admission. Smoking habit has been 1 pack per day for 15 years and drinking habit has been 1 bottle of Soju per day but less flow. In liver function test, AST/ALT were 27/28 IU/l and $\gamma-GT$ was 456 IU/l. In blood test, Hb : 11.5 g/dl, Hct : 34.0% and basophilic stipplings were found in peripheral blood smear. Chest PA was normal and abdominal ultrasonographic finding was non-specific except fatty liver. In the test of lead exposure indices, $PbB:83.0{\mu}g/dl,\;PbU:28.3{\mu}g/l$, and blood ZPP was $300.0{\mu}g/dl$. And in renal function test, BUN : 31.4 mg/dl, blood creatinine : 2.7mg/dl, blood uric acid. 9.1 mg/dl, urinary albumin : 100.0 mg/g creatinine, urinary $\alpha_1-microglobulin$ : 120.5 mg/g creatinine, urinary $\beta_2-microglobulin$ : $183.8{\mu}g/g$ creatinine, and 24 hours urinary creatinine clearance was 31.9 ml/min. The ultrasonoguided renal biopsy showed the global sclerosis of glomerulus, moderate atrophy and loss of tubule, and interstitial fibrosis in light microscopy. There were diffuse losses of brush border of proximal tubule in electronmicroscopy.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.181-189
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• 2018

This study was performed to analyze the dynamics and distributional condition of biological community and to support the basic information about the estuarine ecosystem management by using the intensively surveyed results by each taxon experts around Tamjin river. We analyzed the biological diversity, abundance, correlation among species, and ecological characteristics about 11 taxa groups including vegetation, fish, birds, mammals, etc. in the Tamjin river estuarine ecosystem. We classified vegetation types into 7 physiognomic types and 18 communities according to habitat conditions with the physical environments and salinity. In total, 1125 species including 9 species of endangered species were identified in research area. The species composition and distributional characteristics of each taxon were corresponded to the environmental characteristics of the estuarine ecosystem. Especially, the species diversity and distribution were clearly distinguished in the river according to the difference of the environmental factors such as flow rate, salinity, and soil. Despite the disturbance factors such as barrage and levees, the biodiversity and its distribution were evaluated to be high level under the current environmental conditions. However, loss or reduction of wildlife habitat due to reclamation, embankment, barrage installation and expansion of farmland has been identified as a major threat to the diversity and health of the local ecosystem. The results of this study can be used as a basic data to cope with various development pressure and damage crisis of the whole estuaries including Tamjin river.

• Fire Science and Engineering
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• v.30 no.3
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• pp.31-40
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• 2016

Recently, a curtain wall system was applied to skyscrapers to prevent fire spreading along the vertical direction due to stack effect and outside air flow when a fire breaks out in skyscraper. Conventional sprinklers cannot prevent the spread of fire to the upstairs areas, which increases the loss of life and property. In this study, a water curtain nozzle that creates wider water coverage on the surface of glass and can prevent the spread of fire to the upstairs areas was developed. The spray pattern of the water curtain nozzle was compared with that of a sprinkler to determine performance of the water curtain nozzle. A fire experiment was constructed on the second floor to verify performance of the water curtain nozzle in preventing the spread of fire to the upstairs areas. The fire and watering experiment proved that the water curtain nozzle prevented more effectively the spread of fire than the conventional sprinkler. The position of first crack and critical temperature of fracture were also analyzed using numerical analysis.

• Magazine of the Korean Society of Agricultural Engineers
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• v.24 no.1
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• pp.44-52
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• 1982

Recently, estuary reserovoirs have been actively constructed in Korea and also in Japan there are a large number of estuary reservoirs constructed. But most of the estuary reservoirs are located at the downstream of a river where geographical condition is best for the construction of an enclosing dam. And an effective utilization of water from the estuary reservoir seems to be difficult even if estuary reservoirs are considered to be the water resources the most available for their watershed. Studies on estuary reservoirs so far have been mainly concentrated on the physical and engineering problems of the dam construction itself. The purpose of the present study is to review the estuary reservoir planning in connection with the water resources development and to study a basis of the planning. First, the levels of water use in Korea and Japan were compared with those of other countries in the world. And then, some representative reservoirs were selected to study the roles of a reservoir and water-using conditions in the watershed. Based on the study, a survey was given on the relation between a dam construction upstream and an estuary reservoir construction downstream of a river. Finally, a comprehensive examination was made of the bases of estuary reservoir planning. (1) The estuary reservoir planning is deeply related to the plan for water use develo- pment in the watershed. After the upstream water resources were fully developed up to the most, water reso- urces development by an estuary reservoir should be started. (2) If an estuary lake has a capacity big enough, it can store flood discharge of the watershed without any loss and become a basic facility that will bring about the maxi- mum use of water from the watershed. (3) Estuary reservoirs store water used in the upstream watershed, so recycling of water use is attained by the reservoir. Water in the estuary lake is difficult to be fresh water in its long run. Therefore, estuary reservoir should be located at a place where polluted water is purified and refused. All the planning should be based on the assumption that water in the estuary lake is not fresh but polluted after a long time. (4) The estuary lake can only supply water to the lower basin directly. But the upstream area is benefited from the estuary lake by exchange of irrigation water sources between the lower and the upper area. So a large-scale exchange plan between new and existing water resources is important. By constructing estuary reservoirs and the exchange of water sources between upper and lower areas, the reasonable maximum use of water from the whole watershed is at- tained. (5) The big problem coming from the water resources development by an enclosing estuary is salt water intrusion into the lake. To maintain the estuary lake salt-free, multi-purpose use of the lake should be avoided. It is necessary to take such fundamental measures as abolition of back flow operation of gate, and the closing of the fish port and the fish ladder. The results mentioned above were found in this study and these results of this study could be used for the adequate planning of estuary reservoirs in connection with the maximum water use of the watershed.

• Economic and Environmental Geology
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• v.50 no.4
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• pp.277-286
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• 2017

Mt. Baekdu which located the border of North Korea and China, is known as a potentially active volcano in a typical mountainous terrain. A lahar on the volcanic area is one of the important hazard that can cause the loss of life and property damage. In order to comprehensively address the impact of lahar hazard at Mt. Baekdu, we simulated lahar inundation area using Laharz_py. We assumed 750 m of additional elevation for DEM to draw proximal hazard zone boundary (PHZB) of Mt. Baekdu that H/L ratio are selected 0.10. And lahar volumes for simulation were estimated to $1{\times}10^6$, $5{\times}10^6$, $1{\times}10^7$, $5{\times}10^7$, $1{\times}10^8$, $5{\times}10^8$, $1{\times}10^9m^3$, respectively. In the results, 15 streams are located near a proximal hazard zone boundary, Amnok (Yalu) river (south), Toudaosonghua river, Jinjiang river and Huapi river (west-southwest), Songjiang river, Xiaosha river, Caozi river and Sandaosongjian river (west-northwest), Toudaobai river, Erdaobai river and Sandabai river (north), Wudaobai river-1, -2, -3 (northeast) and Duman (Tumen) river (east). The results of this study can be used as basic data to make a hazard map for reduce the damage that can be caused by volcanic hazards occurred on Mt. Baekdu.