• Membrane and Water Treatment
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• v.7 no.4
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• pp.313-325
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• 2016

South Africa recognises piped water as the main source of safe drinking water supply. Remote areas do not have access to this resource and they rely solely on surface water for survival, which exposes them to waterborne diseases. Interim point of use solutions are not practiced due to their laboriousness and alteration of the taste. Bio-ultra low pressure driven membrane system has been noted to be able to produce stable fluxes after one week of operation; however, there is limited literature on South African waters. This study was conducted on three rivers namely; Umgeni, Umbilo and Tugela. Three laboratory systems were setup to evaluate the performance of the technology in terms of producing stable fluxes and water that is compliant with the WHO 2008 drinking water guideline with regards to turbidity, total coliforms and E.coli. The obtained flux rate trends were similar to those noted in literature where they are referred to as stable fluxes. However, when further comparing the obtained fluxes to the normal dead-end filtration curve, it was noted that both the Umbilo and Tugela Rivers responded similarly to a normal dead-end filtration curve. The Umgeni River was noted to produce flux rates which were higher than those obtainable under normal dead-end. It can be concluded that there was no stabilisation of flux noted. However, feed water with low E.coli and turbidity concentrations enhances the flux rates. The technology was noted to produce water of less than 1 NTU and 100% removal efficiency for E.coli and total coliforms.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.3
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• pp.129-138
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• 1978

The contents of inorganic conservative constituents in the downstream water were determined in spring tides of every month from May 1977 to April 1978 at eight stations of Nagdong River. Samples were taken at the intervals of one or two hours from 7 a. m. to 7 p. m. at each station. Annual ranges and means of the chemical constituents over all the stations except station one, Kupo, ate as follows: pH 6.4-9.3, 7.7; electrical conductivity $0.085-0.345\times10^3\;\mu\mho/cm,\;0.196\times10^3\;\mu\mho/cm;$ chloride 5.8-50.0ppm, 17.7ppm: fluoride ND-0.19 ppm, 0.06 ppm: sulfate 5.5-41.1 ppm, 20.7 ppm; calcium 6-26 ppm, 17 ppm; magnesium 2.0-12.8 ppm, 5.1 ppm; sodium 7-26 ppm, 13 ppm; potassium 1.4-3.8 pprn, 2.3 ppm respectively. The seasonal variations of contents of the chemical constituents were not large and showed nearly definite values at all the stations except station one, Kupo. At station one, seasonal variations were large and the contents were excessively high due to inflow of seawater compared with other stations. The values over 50 ppm in chloride were not determined during the determination period at Mul Geum where the intake station for Busan city water is located. Most constituents except pH and fluoride were over the criteria for drinking water at Kupo, while at other stations only pH value was exceeded the upper limit of the criterion especially in summer period. The pH values tended to increase in the afternoon when water temperature was high. The chloride concentration was shown the highest value at station one, Kupo, with about 2 hours delay after high water of Busan harbour and 3-3.5 hours at Mul Geum.

• Journal of Environmental Health Sciences
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• v.29 no.3
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• pp.65-71
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• 2003

The injection concentration of corrosion inhibitor increases under the pH 7, temperature of 2$0^{\circ}C$, and alkalinity of 35 mg/l (as CaCO$_3$), the corrosion rate gradually decreased. When the corrosion inhibitor of 10 mg/l is injected, the corrosion rate for carbon steel pipe, galvanized steel pipe, and copper pipe reduces for 37, 66 and 61 % respectively that it is more efficient on galvanized steel pipe and copper pipe. As a result of examination of corrosion rate at pH 6, 7, and 8 when injecting 10 mg/l of corrosion inhibitor under the conditions of 2$0^{\circ}C$ in water temperature and 35 mg/l (as CaCO$_3$) in alkalinity, the efficiency of the corrosion inhibitor increases as the pH increases. For carbon steel pipe, it does not show much a difference with the change of the pH condition, but galvanized steel pipe and copper pipe clearly show the corrosion rate depending on the change of the pH condition. The efficiency of corrosion inhibitor is low as the concentration of residual chlorine is high, but it does not show a great influence at 0.4 mg/l or less. For each pipe type, in the case of carbon steel pipe, the range of increase of corrosion speed following the residual chloride is higher than the other pipe types. In the meantime, the effect following the residual chlorine in copper pipe is low.

• Journal of Animal Environmental Science
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• v.7 no.1
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• pp.13-20
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• 2001

This study was conducted to investigate the actual conditions on housing and facilities for goat. This investigation of the actual conditions was investigated by the style of farm which was divided into sideline scale and speciality scale included 47 farms. The results are summarized as follows: Rearing scale was 48.9% for 50-100 heads per farm. Rearing type was 46.8% for grazing type and 53.2% for barn type. Housing type was 27.7% for simple frame housing and 72.3% for permanent housing. Pipe was used 80.8% with Pillar and Girder as the housing frame at farm. For the pipe used in farm, 27.7% of them was used for simple frame housing. Side wall was composed of cement and winch curtain to be 29.8%, slate roof to be 40.4%, pipe partition to be 38.3%, and cement floor to be 51.1%. Materials of feeding trough were wood and Zinc grater to be 41.5%, respectively. Type of feeding trough was square to be 70.2%. The feeding trough was located in barn to be 48.9%. Material of water supply facilities was plastic to be 87.2%. Type of water supply facilities was mostly square to be 76.6%. Water-trough was located in playground to be 48.9%. Parturition facilities were consisted of partition structure by group to be 42.5% and were mainly composed of pipe and wood. 46.8% of the barn did not have delivery room in the farm.

• Korean System Dynamics Review
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• v.1 no.1
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• pp.159-183
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• 2000

How to protect the environment without sacrificing the human environment and economy at the level of region is on of the most difficult issues of recent times. The dynamic Interactions between economic activities and environmental pollution control activities determine whether social welfare is increased of decreased by such activities and provides a basis for saying whether they help or hurt the economy. Bureaucratic Approach of Local government has failed, and an Impetus has arisen to develop new tools of analysis, useful for finding policy leverages focused on sustainability. This paper focus on understanding dynamic relationships between regional economic system and environmental system, and presenting possible framework for finding policy leverages in dynamic interaction behaviors. The case, selected in this study, is Nacdong river regions case, which is related many meaningful issues about sustainable development： two big metropolitan government and dwellers have different opinion with regard to construction of large scale Industrial pack, drinking water supply, and environment model consisting of three sectors： regional economy sector, river pollution and drinking water sector, environmental protection and investment policy sector Finally, this paper deal with how to link policy leverage to causal loop structure for the sustainable development of two regions.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.5
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• pp.333-341
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• 2014

To supply substitution water, $2m^3$ of capacity of rainwater harvesting system is designed calculating rainfall, catchment area and LPCD and has a effects to 34.4% of substitution water supply and 237 days of service day. Rainwater of drinking water quality was judged to be suitable except for bacteria problem, however, groundwater is exceeded in nitrate nitrogen, the evaporation residue and also bacteria, which means that the rainwater is suitable for use as water supply. In addition, to consider cost-benefit ratio, economic analysis conducted. The result is that B/C ratio of RWHS (10 years) is 1.70. It means total benefit is bigger than cost. Except to social factor in this study, there are a variety of benefit such as flood or drought prevention, educational effects inspiring water conservation awareness.

• Journal of Soil and Groundwater Environment
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• v.16 no.6
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• pp.133-142
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• 2011

A total of 247 samples were collected from groundwater being used for drinking-water supply, and hydrogeochemistry and radionuclide analysis were performed. In-situ analysis of groundwaters resulted in ranges of $13.7{\sim}25.1^{\circ}C$ for temperature, 5.9~8.5 for pH, 33~591 mV for Eh, $66{\sim}820{\mu}S/cm$ for EC, and 0.2~9.4 mg/L for DO. Major cation and anion concentrations of groundwaters were in ranges of 0.5~227.6 for Na, 1.0~279.3 for Ca, 0.0~9.3 for K, 0.1~100.1 for Mg, 0.0~3.3 for F, 0.9~779.1 for Cl, 0.3~120.4 for $SO_4$, 0.0~27.4 for $NO_3$-N, and 6~372 mg/L for $HCO_3$. Uranium-238 and radon-222 concentrations were detected in ranges of N.D-$131.1{\mu}g/L$ and 18-15,953 pCi/L, respectively. In case of some groundwaters exceeding USEPA MCL level ($30{\mu}g/L$) for uranium concentration, their pH ranged from 6.8 to 8.0 and Eh showed a relatively low value(86~199 mV) compared to other areas. Most groundwaters belonged to Ca-(Na)-$HCO_3$ type, and groundwaters of metamorphic rock exhibited the highest concentration of Na, Mg, Ca, Cl, $NO_3$-N, U, and those of plutonic rock showed the highest concentration of $HCO_3$, and Rn. Uranium and fluoride from granite areas did not show any correlation. However, uranium and bicarbonate displayed a positive relation of some areas in plutonic rocks($R^2$=0.3896).

• Water for future
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• v.29 no.1
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• pp.191-202
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• 1996

Advanced water treatment for water supply is being introduced for the treatment of various organic materials which cannot be removed by conventional water treatment methods. While the development of advanced water treatment system appropriate to the domestic enviropment of advanced water treatment system appropriate to the domestic environment is essential, the study on the economic costs and the social impact is also of importance. In this paper, it is shown how to estimate the costs (capital and maintenance) for advanced water treatment facilities, especially those using ozone treatment combined with activated carbon process and membrance separation. Estimated costs were compared with the government budget. Also, a general relation between the system capacity and investment was derived. Four alternatives were considered form the aspect of the amount of water to be produced and the delivery system to the user. These alternatives were applied to the city of Pusan. It turned out that bottled water, produced only for drinking, has best economic advantages in having minimum system capacity without detriment to water quality.

• The Korean Journal of Food & Health Convergence
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• v.5 no.6
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• pp.5-9
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• 2019

Desalination requires large energy. This experiment deals to desalinate brackish water through solar panels. The discharge from desalination plants is almost entirely water, and .01 percent is salt. Desalination is a process that extracts minerals from saline water. Solar-powered desalination technologies can be used to treat non-traditional water sources to increase water supplies in rural, arid areas. Water scarceness is a rising dilemma for large regions of the world. Access to safe, fresh and pure clean drinking water is one of the most important and prime troubles in different parts of the world. Among many of water cleansing technologies solar desalination/distillation/purification is one of the most sustainable and striking method engaged to congregate the supply of clean and pure drinkable water in remote areas at a very sound cost. Six types of dripper having discharge 3 - 8 lh-1 were installed one by one and measured discharge and volume of clean water indicated that at 6 lh-1 untreated water discharge have maximum evaporation and volume of clean water was 19.2 lh-1 at same temperature and radiations. Now strategy was developed that when increased the temperature the intake discharge of untreated water must be increased and salt drained water two times more than treated water.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.183-189
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• 2020

Developing countries are areas where many problems arise from poor drinking water infrastructure. Developing countries often use groundwater as their primary source of drinking water, which causes problems. Among them, coastal areas are easily exposed to saltwater intrusion due to their geographical characteristics. Groundwater in areas exposed to saltwater intrusion has higher salinity than usual. If you continue to consume high salinity groundwater can cause a variety of fatal effects on the human body. Therefore, various alternatives have been proposed. This study explores the applicability of CDI(Capacitive Deionization) and RO(Reverse Osmosis) for water purification systems in areas where saltwater intrusion has occurred. Therefore, we will evaluate this by conducting water purification experiment. On the other hand, the supply of electricity is also important in the operation of water purification facilities. However, in many areas of developing countries, electricity is often not available. Therefore, this study intends to calculate the power consumption required for the actual use of the filter and to include it in the evaluation.