• Advances in environmental research
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• v.9 no.1
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• pp.41-54
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• 2020

Industrialization and urbanization are modern need and trends. Such trends affect the natural ecosystem of rivers. Indian rivers face such problems in a high ratio. The aim of this study is to investigate the cause and amount of pollution in a tributary river Krishni. Pre-monsoon sampling of Krishni river water was performed as per APHA standard. Water samples were collected from different sites of Krishni river. Physiochemical parameters as well as trace elements concentrations have been analysed and results were compared with BIS-2012, WHO-2017 and EPA-2001 recommendations. The presence of high BOD, COD, TDS and others physiochemical parameters along with heavy metals reveals that tributary is highly polluted owing to industrial and domestic discharge either directly or through drains. High values of these parameters are harmful for the ecological health of the river because it makes survival of aquatic flora and fauna at risk. On the basis of the results obtained by the present study, it was concluded that level of the pollution in river Krishni is at alarming phase, where if strong action for the rejuvenation of river not takes place, river becomes a dead pool.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.5
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• pp.955-961
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• 2009

Present, a portable battery have problem that the volume increases according to capacity Increase. Direct Methanol Fuel Cell is alternative by solution plan of this problem. In this paper, the characteristics of DMFC are analyzed by change in concentration and discharge of fuel in natural convection and room temperature condition. According to the analysis result, polarization by delay of diffusion velocity of hydrogen ion appeared in methanol of low concentration. And if have a lot of supplies of methanol, generation power declines by electric cell cooling effect.

• Journal of the Korean Applied Science and Technology
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• v.22 no.2
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• pp.142-150
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• 2005

The natural graphite particles A and heat-treated graphite particles B at $1800\;^{\circ}C$ after pitch-coating were used as the anode base materials for lithium ion secondary battery. In order to improve the performance of anode materials, the base anode materials were treated with various acids. With the acid treatments of 62% $HNO_3$ and 95% $H_2SO_4$ aqueous solution, the specific surface area and electrical conductivity of base anode materials were increased, and the initial charge-discharge capacity and cycle performance were improved due to the elimination of structural defects.

• Progress in Superconductivity and Cryogenics
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• v.22 no.2
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• pp.1-6
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• 2020

Large-scale civil engineering works discharge a large amount of soil suspension contaminated with natural heavy metals. Most of the heavy metal ions due to industrial activities and minings are accumulated in the soils and the sediments of lakes and inner bays through the rivers. It is necessary to remove heavy metals from the soils and the sediments, because some of these heavy metals, such as arsenic and cadmium, have significant biological effects even in small amounts. This study proposes a new volume reduction method of the contaminated soils and sediments by superconducting magnetic separation. Our process can remove the specific minute minerals selectively, which adsorbs heavy metals depending on pH. As a fundamental study, the adsorption behaviors of arsenic and cadmium on minute minerals as a function of pH were investigated, and the adsorption mechanism was discussed based on the crystal structure and pH dependence of surface potential in each minute minerals.

• Journal of Environmental Science International
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• v.24 no.3
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• pp.275-280
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• 2015

In order to measure the Radionuclides and Concentration, the directly grinded land samples (river soil, pine leaves and mugwort) among the environment samples around the nuclear power plant were filled in a 450 mL Marinelli beaker and weighed to obtain the dry mass ratio of the samples. Then the background and land samples were measured for 80,000 sec. The analysis of the collected land samples showed that most of them contained less radiation nuclide than the detection minimum limit in the 'Ministry of Education, Science and Technology Public Notice No. 2010-32.'In others, the natural radionuclides $^{40}K$ were detected. Of the products of nuclear reaction discharged by a nuclear reaction, $^{134}Cs$ and $^{137}Cs$ are more easily detected, and their discharge sources can be traced using the relative ratio. Although the radioactive concentration in the vicinity of Kori Nuclear Power Plant, which is more than 1,100km away from Fukushima, the Japanese nuclear accident site, continuous monitoring is needed as the radionuclides can still be accumulated in the soil or animals and plants.

• Carbon letters
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• v.12 no.4
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• pp.243-248
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• 2011

Two different types of graphite, such as flake graphite (FG) and spherical graphite (SG), were used as anode materials for a lithium-ion secondary battery in order to investigate their electrochemical performance. The FG particles were prepared by pulverizing natural graphite with a planetary mill. The SG particles were treated by immersing them in acid solutions or mixing them with various carbon additives. With a longer milling time, the particle size of the FG decreased. Since smaller particles allow more exposure of the edge planes toward the electrolyte, it could be possible for the FG anodes with longer milling time to deliver high reversible capacity; however, their initial efficiency was found to have decreased. The initial efficiency of SG anodes with acid treatments was about 90%, showing an over 20% higher value than that of FG anodes. With acid treatment, the discharge rate capability and the initial efficiency improved slightly. The electrochemical properties of the SG anodes improved slightly with carbon additives such as acetylene black (AB), Super P, Ketjen black, and carbon nanotubes. Furthermore, the cyclability was much improved due to the effect of the conductive bridge made by carbon additives such as AB and Super P.

• The Journal of Korean Physical Therapy
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• v.11 no.2
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• pp.111-114
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• 1999

Some hemiplegic patients show a particular posture that pushing away from the nonaffected side of the body. A few study has been conducted of any aspect of this syndrome. But despite the lack of a scientific basis, this term is widely used in the physical therapy of hemiplegic patients. The purposes of this study was to investigate whether pusher syndrome has an adverse impact on functional outcome. Included were all acute stroke patients admitted in a months period a hospital in Seoul. The presence of pusher syndrome was assessed by a Bobath trained physical therapist. The ability of transfer was assessed by the Functional Independence Measure(FIM), Activities of daily living by the Modified Barthel Index(MBI), and standing balance by Bohannon's Standing Balance Scale(BSBS) on admission, weekly during the hospital stay, and at discharge. Pusher syndrome was found in $52.4\%$ of the left side and $50.0\%$ of the right aide hemiplegic patients. Significant differences were found in the score of transfer, ADL and standing balance between patients with and without pusher syndrome.

• Journal of Korean Society on Water Environment
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• v.24 no.6
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• pp.651-658
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• 2008

Estuary barrier is a hydraulic structure constructed to supply safely water as protecting chlorine penetration of sea water. However, the barrier brings about a problem which decreases original functions of estuary because hydraulic ecology was disrupted as obstructing natural water exchange between fresh water and sea water. It is important to supply Enough fresh water in the estuary ecosystem. But it is possible to reduce the problems brought from barrier throughout efficient water gate operation of estuary barrier. It was shown in this study that the environmental effect of estuary in Nakdong river was investigated according to the control of water level. Also, the basic information about the effective water gate operation was provided. The analysis results showed that the release rate of estuary was increased about 20% as changing the operational water levels. This helps supplying fresh water durably to the mixing zone. Also, CE-QUAL-W2 model was utilized to assess water quality. The values of BOD and COD were not changed in estuary area. From the result, it was analyzed the effect of water quality according to the water gate operation was not indicated.

• Journal of Biosystems Engineering
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• v.30 no.4 s.111
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• pp.229-234
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• 2005

Kinetic friction coefficient, bulk density, dynamic and static angle of repose, and terminal velocity of rice husk at the moisture range 7 to $23\%$ w.b. were determined. It could lead to better design and operation of the processing machinery and handling facilities. Friction coefficient was determined from the horizontal traction force measured by pulling the container holding a mass of rice husk on various plate materials. Dynamic angle of repose was calculated from the photos of bulk samples piled by gravity flow on a circular platform. Static angle of repose was determined by measuring the side angle of the bulk material which was left in a cylindrical container after natural discharge of the bulk sample through a circular hole in the bottom plate. Kinetic friction coefficients of rice husk were in the range of $0.254\~0.410,\;0.205\~0.520,\;0.229\~0.400,\;and 0.133\~0.420$ on PVC, mild steel, galvanized steel, and stainless steel, respectively. Bulk density, dynamic and static angle of repose, and terminal velocity were in the range of $91.7\~98.3$ $kg/m^3$, $40.2\~47.6^{\circ},\;52.8\~83.7^{\circ},$ and $1.36\~1.73$ m/s, respectively. These physical properties of rice husk increased linearly as the moisture content increased.

• Journal of Biosystems Engineering
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• v.23 no.6
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• pp.583-590
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• 1998

This study was performed to determine the kinetic friction coefficient bulk density, dynamic and static angle of repose, and terminal velocity of the chopped rice straw in the moisture range of 8~23%, which could be used for better design and operation of the processing machinery and handling facilities. Friction coefficient was determined from the horizontal traction force measured by pulling the container holding the mass of rice straw on the various plate materials. Bulk density was measured with an apparatus consisting of a filling funnel and a receiving vessel. Dynamic angle of repose was calculated from the photos of bulk samples piled by gravity flow on a circular platform. Static angle of repose was determined by measuring the side angle of the bulk material which was left in the cylindrical container after natural discharge of the bulk sample through a circular hole in the bottom plate. Kinetic friction coefficients of rice straw on the PVC, mild steel, stainless steel, and galvanized steel were in the range of 0.303~0.434, 0.222~0.439, 0.204~0.448, and 0.206~0.407, respectively. and indicated linear increase with moisture content. The effects of moisture change on the friction coefficients were in the order of PVC, mild steel, galvanized steel, and stainless steel. Bulk density, dynamic and static angle of repose, and terminal velocity were in the range of 56.8~60.3 kg/m$^3$, 41.4~45.9$^{\circ}$, 94.4~100.8$^{\circ}$, and 1.07~4.48 m/s, respectively, and were increased linearly with the moisture content.