• Title/Summary/Keyword: Water transportation

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An Analysis of the Economic Effects of Marine Transport and Port Industry (해운.항만산업의 경제적 파급효과 분석)

  • Jeong, Boon-Do;Shim, Jae-Hee
    • Journal of Korea Port Economic Association
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    • v.27 no.3
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    • pp.311-329
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    • 2011
  • This study examined economic ripple effect of marine transport and port industry using Input-Output Tables. The results of the study are summarized as follows: first, in 2005 production inducement coefficients of harbour facilities was the highest(1.958), followed by coast and inland water transportation(1.857), load and unload(1.842), other transportation services(1.768), storage and warehouse(1.676), water transportation assistant services(1.422), and outport transportation (1.283). Second, value added inducement coefficient of water transportation assistant services was the highest(0.924), followed by load and unload, storage and warehouse(0.902), other transportation services(0.885), harbor facilities(0.832), coast and inland water transportation (0.752), and outport transportation(0.258). Third, import inducement coefficient of outport transportation was the highest(0.742), followed by coast and inland water transportation, harbor facilities, other transportation services, load and unload, storage and warehouse, and water transportation assistance services. Fourth, indexes of the sensitivity of dispersion of other transportation services and load and unload were 1.125 and 0.882 respectively while those of harbor facilities and outport transportation were 0.514. Indexes of power of dispersion of harbor facilities, coast and inland water transportation, load and unload, and other transportation services were the highest, respectively 1.006, 0.954, 0.946, and 0.908 while that of outport transportation was low, 0.659.

Water Repellent Finish of Polyester Fabric Using Glow Discharge Treatment (글로우방전을 이용한 폴리에스테르 직물의 투습방수성 개질)

  • 김태년
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.1
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    • pp.154-161
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    • 2001
  • We have treated polyester fabric with $CF_4,\;C_2F_6,\;SF_6\;and\;C_3F_6$ glow discharge plasmas to develop functional fabrics which preserve moisture transportation and water proofing nature. Modified properties were evaluated by water vapor permeation rate and breakthrough water pressure. The change of surface morphology was observed by SEM. Fiber interstice of the plasma treated fabric was calculated as $0.32{\mu}{\textrm}{m}$, and this value was sufficiently ideal as water repellent material. The moisture transportation of ${CF_4}-treated$ fabric was good as much as untreated fabric, and those of $C_2$F(sub)6-treated, SF(sub)6-treated fabrics were reduced by 1~3%, and that of ${C_3F_6}-treated$ fabric was reduced by 15%. The best treatment condition were 0.06 torr 120 seconds in $CF_4$, 0.05 torr 30 seconds in $SF_6$, 0.08~0.15 torr 90 seconds in $SF_6$ and 0.1 torr 45 seconds in $C_3F_6$ respectively. The grade of moisture transportation effect was $CF_4>C_2F_6>SF_6>>C_3F_6$, and water proofing effect was $C_2F_6{\approx}CF_4>C_3F_6>SF_6$. It was observed by SEM that the thin film was formed on the surface of the treated substrate by the fluorocarbon plasma treatment.

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A Study on the Improvement of Water-Leakage Detection Reliability in Local Heating System (지역난방배관의 누수감지 신뢰성 향상에 관한 연구)

  • 신춘식;안영주;변기식
    • Journal of the Korean Society of Safety
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    • v.14 no.1
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    • pp.66-72
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    • 1999
  • Local heating transportation pipe has sensor and return lines to detect water-leakage. There are impulse and resistance comparison measurement types for a water-leakage detection. The impulse type shows large detection error within a measurement range. Since the resistance comparison type can find a comparative accurate single water-leakage point in the measurement range of heating pipe, it has been used to detect water-leakages these days. However if the multi water-leakages are happened in the measurement range of transportation pipe. the resistance comparison type shows a detection error point by the parallel resistance between a detection sensor line and ground. But the detection error will be minimized by the divided transportation pipe loops. In this research, it suggests the design of remote controlled detection system which can divide a large pipe loop and a possible single water-leakage measurement process in each divided loops.

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Primary Ecological Effect Analysis of Emergent Water Transportation in the Lower Reaches of Tarim River Based on RS Technology

  • Xu, Mei;Huang, ShiFeng;He, Yu
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.1301-1303
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    • 2003
  • Tarim River is the biggest inland river in China, its problem of eco-environment is worsening in the lower reach. For keeping this trend within limits, the measure of emergent water transportation to the lower reach was taken. In this paper, the remote sensing technology will be applied to the analysis of eco-environment effect after water transportation. The result is: the vegetation index and cover ratio increased but not markedly, the eco-environment situation can't been improved obviously up to now. It is some effective but temporary . The continuity, quality and quality of water source for the Tarim River must been ensured.

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High-valence Mo doping for promoted water splitting of Ni layered double hydroxide microcrystals

  • Kyoungwon Cho;Seungwon Jeong;Je Hong Park;Si Beom Yu;Byeong Jun Kim;Jeong Ho Ryu
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.33 no.2
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    • pp.78-82
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    • 2023
  • The oxygen evolution reaction (OER) is the primary challenge in renewable energy storage technologies, specifically electrochemical water splitting for hydrogen generation. We report effects of Mo doping into Ni layered double hydroxide (Ni-LDH) microcrystal on electrocatalytic activities. In this study, Mo doped Ni-LDH were grown on three-dimensional porous nicekl foam (NF) by a facile solvothermal method. Homogeneous LDH structure on the NF was clearly observed. However, the surface microstructure of the nickel foam began to be irregular and collapsed when Mo precursor is doped. Electrocatalytic OER properties were analyzed by Linear sweep voltammetry (LSV) and Electrochemical impedance spectroscopy (EIS). The amount of Mo doping used in the electrocatalytic reaction was found to play a crucial role in improving catalytic activity. The optimum Mo amount introduced into the Ni LDH was discussed with respect to their OER performance.

The motion rule of sand particles under control of the sand transportation engineering

  • Xin, Lin-gui;Cheng, Jian-jun;Chen, Bo-yu;Wang, Rui
    • Wind and Structures
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    • v.27 no.4
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    • pp.213-221
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    • 2018
  • In the desert and Gobi regions with strong wind and large sediment discharge, sand transporting engineering is more effective than sand blocking and sand fixing measures in sand prevention. This study uses the discrete phase model of 3D numerical simulation to study the motion trail, motion state and distribution rule of sand particles with different grain diameters when the included angle between the main shaft of the feather-row lateral transportation sand barrier and the wind direction changes, and conducts a comparison in combination with the wind tunnel test and the flow field rule of common sand barrier. According to the comparison, when wind-sand incoming flow passes through a feather-row sand barrier, sand particles slow down and deposit within the deceleration area under the resistance of the feather-row sand barrier, move along the transportation area formed by the transportation force, and accumulate as a ridge at the tail of the engineering. With increasing wind speed, the eolian erosion of the sand particles to the ground and the feather-row sand barrier is enhanced, and the sand transporting quantity and throw-over quantity of the feather-row sand barrier are both increased. When sand particles with different grain diameters bypass the feather-row sand barrier, the particle size of the infiltrating sands will increase with the included angle between the main shaft of the feather-row sand barrier and the wind direction. The obtained result demonstrates that, at a constant wind speed, the flow field formed is most suitable for the lateral transportation of the wind-drift flow when the included angle between the main shaft of the feather-row sand barrier lateral transportation engineering and the wind speed is less than or equal to $30^{\circ}$.

Determination of Pollutant Unit Loads from Various Transportation Landuses (교통관련 포장지역 비점오염원에서의 오염물질 유출원단위 산정)

  • Lee, So-Young;Lee, Eunju;Maniquiz, Marla C.;Kim, Lee-Hyung
    • Journal of Korean Society on Water Environment
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    • v.24 no.5
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    • pp.543-549
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    • 2008
  • Human activities and land-use practices are intensely widening the urban areas. High impervious surface areas cover much of urban landscapes and are the primary pollutant sources which can lead to water quality and habitat degradation in its watershed. As the urban areas expand, transportation land-use such as parking lots, roads, service areas, toll-gates in highways and bridges also increase. These land-uses are significant in urban pollution due to high imperviousness rate and vehicular activities. To regulate the environmental impacts and to improve the water quality of rivers and lakes, the Ministry of Environment (MOE) in Korea developed the Total Pollution Load Management System (TPLMS) program. The main objective is to lead the watershed for a low impact development. On a local scale, some urban land surfaces can be emitting more pollution than others. Consequently, in urban areas, the unit loads are commonly employed to estimate total pollutant loadings emitted from various land-uses including residential, commercial, industrial, transportation, open lands such as parks and golf courses, and other developed land like parking areas as a result of development. In this research, unit pollutant loads derived specifically from transportation land-uses (i.e. branched out from urban areas) will be provided. Monitoring was conducted over 56 storm events at nine monitoring locations during three years. Results for the unit pollutant loads of transportation land-use are determined to be $399.5kg/km^2-day$ for TSS, $12.3kg/km^2-day$ for TN and $2.46kg/km^2-day$ for TP. The values are higher than those of urban areas in Korean MOE and US highways. These results can be used by MOE to separate the pollutant unit load of transportation landuses from urban areas.

Flow Analysis of Water Pump for Clean Disel Engine Application (클린 디젤엔진용 워터펌프 유동해석)

  • Lee, Dongju;Kim, Taeyoung;Chon, Mun Soo
    • Journal of Institute of Convergence Technology
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    • v.4 no.2
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    • pp.61-65
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    • 2014
  • Pressure distribution around rotating impeller blades in centrifugal pump has been main issue for design of efficient and high performance automotive water pump. In addition, pressure losses of inlet water pipes should be considered to reduce additional pressure drop and design high performance engine cooling system. In this paper, pressure distribution inside water pump and pressure drop between inlet and outlet of water pump are investigated numerically to design plastic water pump for clean diesel engine application. And the inlet geometry of water pump was considered to analysis the effect of inlet water pipe geometry on pressure distribution around impeller blades and outlet pressure. The prediction results are compared with experimental data to validate and determine optimal operation condition without water pump cavitation. Major design parameters such as blade angle, volute geometry, system pressure, and coolant flow rate are considered to confirm applying possibility of plastic blades to the clean diesel engine.

Water Transportation and Stratification Modification in the Andong-Imha Linked Reservoirs System (안동호-임하호 연결에 따른 물 이동과 수온성층 변화)

  • Park, Hyeung-Seok;Chung, Se-Woong
    • Journal of Korean Society on Water Environment
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    • v.30 no.1
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    • pp.31-43
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    • 2014
  • Recently, Andong Reservoir and Imha Reservoir located in Nakdong River basin (Korea) are being connected by a tunnel (length 2km, diameter 5.5m) for a conjunctive use. The objectives of this study were to construct a two dimensional(2D) laterally-averaged model for two reservoirs, and examine the effects of connection on the water transportation and temperature stratification in the reservoirs. The 2D models for each reservoir were calibrated using field data obtained in 2006, and applied to the linked system for the year of 2002 when a severe flood intruded into Imha Reservoir during the typhoon Rusa. Simulation results showed that 364 million $m^3$ of water can be conveyed from Imha to Andong, while 291 million $m^3$ of water from Andong to Imha after connection. It resulted in 1.38 m increase of annual averaged water level in Andong Reservoir, whereas 3.75 m decrease in Imha Reservoir. The structures of thermal stratification in both reservoirs were influenced in line with the flow exchanges. In Andong Reservoir, the location of thermocline moved upward about 10 m compared to an independent operation. The results imply that the persistent turbidity issue of Imha Reservoir might be shifted to Andong Reservoir during a severe flood event after connection.

A Comparative Study on the Effect of Tamping Materials on the Impact Efficiency at Blasting Work (발파작업 시 충전매질에 따른 발파효과 비교 연구)

  • Bae, Sang-Soo;Han, Woo-Jin;Jang, Seung-Yup;Bang, Myung-Seok
    • Journal of the Korean Geosynthetics Society
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    • v.21 no.2
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    • pp.57-65
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    • 2022
  • This study simulated the shock wave propagation through the tamping material between explosives and hole wall at blasting works and verified the effect of tamping materials. The Arbitrary Lagrangian-Eulerian(ALE) method was selected to model the mixture of solid (Lagrangian) and fluid (Eulerian). The time series analysis was carried out during blasting process time. Explosives and tamping materials (air or water) were modeled with finite element mesh and the hole wall was assumed as a rigid body that can determine the propagation velocity and shock force hitting the hole wall from starting point (explosives). The numerical simulation results show that the propagation velocity and shock force in case of water were larger than those in case of air. In addition, the real site at blasting work was modeled and simulated. The rock was treated as elasto-plastic material. The results demonstrate that the instantaneous shock force was larger and the demolished block size was smaller in water than in air. On the contrary, the impact in the back side of explosives hole was smaller in water, because considerable amount of shock energy was used to demolish the rock, but the propagation of compression through solid becomes smaller due to the damping effect by rock demolition. Therefore, It can be proven that the water as the tamping media was more profitable than air.