• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2004.11a
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• pp.133-136
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• 2004

In-situ collection experiments were performed to analyze inflowing sedilnents behavior as a basic study of topographical change in Nakdong River Estuary. Sediment rate and bed load flux ranged from 0.0004 to $0.472\;g/cm^2/day\;and\;0.0005\~1.7579\;g/cm^2/day$, respectively. The settling velocity of suspended particulate matter was estimated in tire range of $0.339\~1.010\;cm/sec$, The grain size analysis shows that surface sediments in backside of sandbar and bed load in front of dike have a similar grain size distribution. It is considered that the source of surface sediments in backside of sandbar were flowed in from Nakdong River. In order to verify the characteristics of inflowing sediments behavior, detailed surveys around Nakdong River Estuary need to be carried out, continuously.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.522-529
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• 2014

Circulating fluidized bed system consists of SEWGS reactor - lower loop seal - regeneration reactor - riser - cyclone - upper loop seal has been used for solid circulation between the SEWGS reactor and the regeneration reactor in a SEWGS system for pre-combustion $CO_2$ capture. A vertical type lower loop seal has been used in current system but this lower loop seal requires high gas flow rate through the lower loop seal for fluidization and smooth solid circulation, and consequently, causes slugging behavior sometimes. To overcome these disadvantages, inclined type lower loop seal was proposed by this study. Solid circulation characteristics with change of lower loop seal geometry were measured and compared in a bubbling - bubbling - riser type circulating fluidized bed using $CO_2$ absorbent (P-78) as bed material at ambient temperature and pressure. We could conclude that the inclined lower loop seal is better than the vertical type lower loop seal from the viewpoints of minimum flow rate requirement for stable solid circulation and solid height change during solid circulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.1500-1506
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• 2015

The headcut erosion at the confluence section of a mainstream and tributary can migrate up the tributary streams, and rapid degradation can threaten the stability of hydraulic structures installed in the channel. Therefore, quantitative analysis for the development and mechanism of headcut erosion is needed to prevent damage due to the headcut. In this study, hydraulic experiments for headcut erosion in the channel with noncohesive materials were performed and the knickpoint movement and final bed slope change were analyzed based on the different hydraulic conditions. As a result, the knickpoint movement was 1.5 times faster when the difference in velocity between the upstream and downstream sections was 2.5 times greater and the central part of the cross-section was eroded and collapsed earlier than the left and right sides. The movement length of headcut erosion was longer and the final bed slope was milder as the velocity difference between the upstream and downstream sections was increased. This study showed that a correlation between the knickpoint movement and bed slope change by headcut erosion and the water level difference of upstream and downstream sections was not constant compared to the velocity difference.

• Journal of Mushroom
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• v.16 no.4
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• pp.342-346
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• 2018

The temperature and humidity of 49 greenhouses for oak mushroom cultivation were investigated for 5 years to analyze the trends in the change of these parameters according to the climate change in Korea. The 5-year average temperature and humidity were $24.7^{\circ}C$ and 60.5%, respectively, in sawdust media-based cultivation houses and $24.4^{\circ}C$ and 60.0%, respectively, in log-bed cultivation houses. The average temperature in the summer was $29.8^{\circ}C$ in 2016, $29.1^{\circ}C$ in 2017, and $33.3^{\circ}C$ in 2018 in the log-bed cultivation houses and $26.8^{\circ}C$ in 2016, $20.4^{\circ}C$ in 2017, and $24.2^{\circ}C$ in 2018 in the sawdust media-based cultivation houses. During the investigation, temperatures over $30^{\circ}C$ were detected in one cultivation house in spring and five such houses in summer. When classifying by cultivation type, temperatures over $30^{\circ}C$ were found in five log-bed cultivation houses and temperatures less than $20^{\circ}C$ were found in four log-bed cultivation houses in fall. This study shows that log-bed cultivation houses for oak mushroom need to be modified to cope with the climate change.

• The Korean Journal of Health Service Management
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• v.5 no.4
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• pp.127-136
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• 2011

The improving in physical activity of Disability elder is the most important and effective way of prevent and treatment. Especially, It improves ADL(Activities Daily of Living) by decreasing restrictive function and dependence. This study was researched on change by comparing before and after about ADL of Women elders who were instructed self rehabilitation exercise in bedside and have been take that. The whole subjects are 92 persons. Elders aged 65 to 69 are 32 persons. elders aged 70 to 74 are 22 persons 38 persons are over the age of 75. This study shows that the whole subjects have been improved ADL. especially, "Take a bath" in detail items of ADL comes to the most improvement rate. Next, "Sit to stand on the bed and transfer" comes to the second highest rate. According to findings upon the age group. "Take a bath" is also the highest improvement rate. Elders aged 60 to 65 show "Sit to stand on the bed and transfer" is the second highest rate of improvement" and elders aged 70 to 74 show that "control urine" is the second highest rate of improvement. and elders over the age of 75 shows that "sit to stand on the bed and transfer" is the second highest rate of improvement. This study have some problems on having possibilities of results because hospitalized persons have answered imperfect statement and being compare progressed for short term with rehabilitation exercise. so, There are some causes that is early to be generalized.

• The Journal of Korean Physical Therapy
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• v.23 no.2
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• pp.61-68
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• 2011

Purpose: The purpose of this study was to provide basic data for the effectiveness and the necessity of home visiting physical therapy through examining performance ability and functional changes in daily life activities by investigating the life of disabled persons living at home. Methods: After selecting 100 people with physical disabilities greater than level 3 and brain damage related disabilities living in Youngam-Gun, we conducted mobility tests according to a Modified Bathel Index (MBI), the Berg Balance Scale (BBS), and floor and bed movements? for Activities of Daily Living evaluation. We did this before the experiment and after doing home visiting physical therapy for 90 minutes at a time, once a week for 6 months Results: 1) Persons who live in a bed are higher than those who live in a floor. There was a significant difference between persons who live in a floor and those who live in a bed in the change in MBI and BBS scores after home visiting physical therapy. 2) Those with a musculoskeletal disorder had a significantly different change in MBI and BBS according to the type of disease and kind of disability. Those with neuropathy had a significantly different change in MBI. Those with physical disabilities showed a significant difference in MBI and BBS. Conclusion: A home visiting physical therapist can cause an improved performance ability and lead to the ability of disabled persons living at home to carry out activities of daily livingin a large part and the study for brain lesion disabilities except physical disabilities and stroke which occupy large proportion of disabled persons should be done.

• Journal of Korea Water Resources Association
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• v.31 no.5
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• pp.575-586
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• 1998

A relaxed similarity theory which can be applied to river models with movable beds is established by modifying existing theory by Einstein and chien(1954). Experimental data collected from river models with movable beds were used to evaluate the applicability of the proposed theory. Effects of similarity of flow, ΔFΔM, and similarity of sediment movement, ΔFs, were examined by analyzing the behaviour of total river-bed change. The results show that the smaller ΔFΔM or ΔFs is, respectively, the larger total sedimentation is. The modified similarity theory established in this study would be useful and practical whenever it is impossible or very difficult to satisfy strict theoretical requirements concerning the river model experiments with movable beds. Keywords : river model, similarity of flow, similarity of sediment movement, sediment transport, river-bed change.

• Journal of Korea Water Resources Association
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• v.35 no.6
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• pp.753-762
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• 2002

In-stream vegetation is an essential element of a stream channel. Vegetation plays an important role in flood control and the natural environment in stream channels. This research investigates the relationship between in-stream vegetation and stream changes. This study investigates the distribution characteristic of vegetation in some rivers of Korea. Although there are many physical factors that cause changes to streams, this research verified that in-stream vegetation caused sediment deposition. A hydraulic model experiment was conducted. Tests were conducted in a simulated gravel bed stream (bed slope 1/200) with Phragmites japonica. The average diameter of the bed load used was 0.3 mm and 27 kg were uniformly supplied for 1 hour under same hydraulic conditions. The deposition and scouring as well as the change of flow differed according to the density and arrangement of the Phragmites japonica. In-stream vegetation and stream channel change are closely related because deposition and scouring affects the distribution of vegetation.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.791-793
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• 2009

Hydrogen has been recognized of the energy source for the future, in terms of the most environmentally acceptable energy source. A pressurized fluidized bed reactor made of carbon steel with 0.076 m I.D. and 1.0 m in height was employed for the thermocatalytic decomposition of methane to produce amount of $CO_2$ - free hydrogen with validity from a commercial point of view. The fluidized bed was proposed for withdrawing of product carbons from the reactor continuously. The methane decomposition rate with the carbon black N330 catalyst was rapidly reached a quasi-steady state and remained for several hour. The methane thermocatalytic decomposition reaction was carried out at the temperature range of 850 - 950 $^{\circ}C$, methane gas velocity of 2.0 $U_{mf}$ and the operating pressure of 1.0 -3.0 bar. Effect of operating parameters such as reaction temperature, pressure on the reaction rates was investigated and predicted the effect of a change in conditions on a chemical equilibrium thermodynamically, according to Le Chatelier's principle.

• Journal of Electrical Engineering and Technology
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• v.9 no.6
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• pp.1851-1863
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• 2014

Many countries are increasing their investments in smart grid technology to enhance energy efficiency, address climate change, and trigger a green energy revolution. In addition to these goals, Korea also seeks to promote national competitiveness, prepare for the growth of the renewable energy industry, and export industrialization through its strategic promotion of the smart grid. Given its inherent representativeness for Korean implementation of the smart grid and its growth potential, Jeju Island was selected by the Korean government as the site for smart grid testing in June 2009. This paper presents a new design for the electricity market and an operational scheme for testing Smart Electricity Services in the Jeju smart grid demonstration project. The Jeju smart grid test-bed electricity market is constructed on the basis of day-ahead and real-time markets to provide two-way electricity transaction environments. The experience of the test-bed market operation shows that the competitive electricity market can facilitate the smart grid deployment in Korea by allowing various demand side resources to be active market players.