• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1417-1429
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• 2004

The objective of the paper was to study the drinking and other related behavior of dairy cows (Bos taurus). There were 142 Holstein dairy cows observed and compared in this study. The experiment was designed on the basis of two different housing systems (wet pad with forced ventilation cooling house and open house); two different seasons (winter and summer); four different stages (high milk yielding cows, low milk yielding cows, dry cows, and heifers); and grouping (home and visitor animals). All cows had free access to water. Dairy cows spent 13.8 min/day drinking in wet-pad house and 11.7 min/day in open house. owever, there was no significant difference in the duration of water drinking between these two housing systems (p>0.05). The water consumption was significantly higher in wet-pad housed animals (68 L/day) than open-housed animals (31.5 L/day) (p<0.05). A significant interaction between housing and grouping (p<0.05) was found. Home and visitor animals spent more time drinking in open house, wet-pad house, respectively. A highly significant interaction was found between housing and drinking time during the day (p<0.001). Animals in open house drank more during the morning (6:00 to 10:00 h), whereas wet-pad housed animals drank in the afternoon (14:00 to 15:00 h) and evening (18:00 to 20:00 h). The average time a cow spent in drinking in summer was not ignificantly different from that of drinking in winter. However, the water intake was significantly higher in summer (61.9 L/day) than in winter (38.6 L/day) (p<0.05). Drinking activity showed a highly significant interaction between season and physiological stage (p<0.01). High milk yield cows spent more time drinking in summer than in winter, whereas cows in all other stages followed the opposite drinking pattern. Grouping exchange did not influence the drinking behavior of dairy cows in either season (p>0.05); both home and visitor animals spent almost the same time in drinking water. A strong significant interaction between season and time during the day was found(p<0.01), suggesting that animal's high drinking frequency occurred during the daytime for both seasons, with a peak midday in winter and two peaks at 10:00 h in the morning and 19:00 h in summer. Thus, drinking behavior was associated with the cooler time of day in summer and with the warmer hours of day in winter. High and low milk yielding cows and heifers spent 15.3 min/day, 14.3 min/day, and 12.8 min/day, respectively, in water drinking activity, but there was no significant difference among them (p>0.05). There was, however, a significant difference in water drinking activity found in dry cows, which spent less time in drinking at 8.2 min/day (p<0.05).

• Journal of Korean Society of Water and Wastewater
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• v.34 no.5
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• pp.357-371
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• 2020

Microplastics have become a rising issue in due to its detection in oceans, rivers, and tap water. Although a large number of studies have been conducted on the detection and quantification in various water bodies, the number of research conducted on the removal and treatment of microplastics are still comparatively low. In the current research, the inflow and removal of microplastics were investigated for various drinking water treatment plants around the world. Addition to the investigation of filed research, a survey was also conducted on the current research trend on microplastic removal for different treatment processes in the drinking water treatment plants. This includes the researches conducted on coagulation/flocculation, sedimentation, dissolved air flotation, sand filtration and disinfection processes. The survey indicated mechanisms of microplastic removal in each process followed by the removal characteristics under various conditions. Limitations of current researches were also mentioned, regarding the gap between the laboratory experimental conditions and field conditions of drinking water treatment plants. We hope that the current review will aid in the understanding of current research needs in the field of microplastic removal in drinking water treatment.

• Environmental Engineering Research
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• v.18 no.2
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• pp.109-114
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• 2013

In Cukhe, a village located in the outskirts of Hanoi, Vietnam, people suffer from a shortage of high-quality water due to an arsenic contaminated supply water resource. We installed catchments, filters and settled tanks in the existing rainwater harvesting facility to improve water quality, and ten portable rainwater tanks to provide good-quality drinking water to the poor households and kindergartens in the dry season. The triple bottom line considerations, as well as the environmental, economic, and social impacts of the rainwater harvesting (RWH) systems are examined. RWH is a sustainable method to obtain good-quality drinking water at low cost and with little energy expenditure. Education of the system also encourages that continuation of the system and expansion can lead into economic prosperity, as the safe drinking water can be sold to the community. Hence, RWH is a unique proposal as sustainable drinking supply water for improving the lives and health of residents in Cukhe and other sites where water supply sources are contaminated.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.05a
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• pp.69-70
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• 2002

Arsenic (As) is a ubiquitous element found in several forms in foods and environmental media, such as soil, air, and water. The primary route of human exposure is through ingestion of arsenic-contaminated food and drinking water. The predominant form of arsenic in drinking water is inorganic arsenic, which is both highly toxic and readily bioavailable.(omitted)

• Journal of Korean Society on Water Environment
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• v.38 no.6
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• pp.275-281
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• 2022

To maintain water quality after water treatment, monitoring whether the quality of treated tap water quality changes is essential. However, current investigations are insufficient to prevent secondary contamination in drinking water supply systems. This study investigated Gyeonggi's e apartment where a red water problem occurred and monitored the water quality and corrosiveness of the overall water supply system to the apartment from June 2021 to April 2022. In a comparison of drinking water quality after water treatment and the influent of the reservoir, turbidity and heavy metal concentrations were increased and residual chlorine was decreased due to increases in temperature. Correlation analysis and principal component analysis (PCA) indicated that a low level of residual chlorine may cause the abscission of Mn²⁺ and Fe²⁺ through microorganism activation, which also causes a high level of turbidity. The corrosion index (LI) in the influent of the reservoir tank was increased due to Ca²⁺ and temperature. These results indicate that the corrosiveness of drinking water and the deterioration of drinking water quality were mainly increased between the drinking water treatment plant and the reservoir tank's influent. The findings provide clear evidence that it is essential to manage water supply systems and reservoir tanks to prevent the secondary contamination of drinking water.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.1
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• pp.96-102
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• 2011

In this study, we examined the effects of formic acid administration to the drinking water on performance, intestinal microflora and carcass contamination in male broilers. A total of 312 day-old male broiler chicks were allocated to two groups with three replicates. The first group (control) received normal drinking water (pH 7.4) during the experiment. The second group consumed acidified drinking water (pH 4.5) after 5 d of age. At 43 d of age, twelve birds were randomly selected from the control group to determine the effect of acidified drinking water on carcass contamination. These birds were only given normal or acidified (pH 3) drinking water for 8 h prior to slaughter. The reduction of water pH from 7.4 to 4.5 significantly decreased body weights of male broilers at 21 and 42 d of age. However, no differences were observed between male broilers given normal and acidified drinking water in terms of feed intake, feed conversion ratio and mortality. The pH value of the gizzard contents was not significantly affected by acid water treatment. There were no significant differences in the intestinal population of E. coli, total organism and Salmonella between the groups. The total organism and E. coli counts of the carcass slightly decreased in the acidified group. No Salmonella was identified in carcass samples of any of the treatment groups. The results showed that drinking water acidification did not provide beneficial effects on performance, intestinal microflora and carcass contamination in male broilers.

• Journal of Korean Society on Water Environment
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• v.21 no.3
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• pp.219-229
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• 2005

The analytical methods for dioxins in water sample from wastewater to tap water were reviewed. For extraction method, liquid-liquid extraction (LLE) has been widely used, however, this process needs too much time and man power. New approach including solid phase extraction (SPE) is now applicable to large volume of water sample with high extraction efficiency. Column clean up in classical analytical methods were very complex and time consuming procedures during decade. Modifications were tried to decrease solvent and reagents volume. Moreover, use of column connection method has been demonstrated in the environmental matrices. Instrumental configurations also have been improved, in which GC/MS/MS with large volume injection approach can analyze picogram levels. Absolute sensitivities of HRMS increased compared to old versions of double focusing sector type mass spectrometers. Based on these analytical evolutions during last 10 years, we tried to optimize the analytical method for dioxins in water sample from sample extraction to instrumental analysis.

• Journal of Environmental Health Sciences
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• v.33 no.5
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• pp.428-433
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• 2007

To clarify the pioneer group in the development of biofilms in high chlorine residual water, a semi-pilot model system was operated and 16S rDNA V3 targeted PCR-DGGE was submitted. Biofilm formation occurred rapidly in the model of a drinking water distribution system. It reached $10^3\;CFU/cm^2$ or more on the surface of stainless steel, PVC, and galvanized iron in chlorinated (1.0 mg/l) water within a week. Within a week, uncultured Proteobacteria- and Bacillales group-like sequences were detected and Sphingomonas-like sequences were identified from all season and all pipe materials tested. Hence Sphingomonas species were regarded as the potential pioneer group in the development of biofilm in drinking water and this results would be useful for the prevention of biofilm formation and safety of drinking tap water.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.275-279
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• 2003

A water quality analysis of rainwater collected from catchment equipment(2m${\times}$1m) was conducted to determine its suitability for domestic purposes, in this study. As the results of analysis, the pH of rainwater was 6.3${\pm}$0.3, and the turbidity of rainwater was over the 5 times than drinking water guidelines. For the usage of rainwater as the domestic and drinking water, the rainwater is need to treat. The analysis value of BOD was about 3 mg/L and the values of heavy metal as the Pb, Cd, Fe, Mn, Cr$\sub$6/$\^$+/and Cu was satisfied with drinking guidelines. Overall results of analysis support the possibility of rainwater as the domestic and drinking water.

• Membrane Journal
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• v.13 no.1
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• pp.1-8
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• 2003

Membrane filtration systems have been focusing and increasing rapidly in the filed of drinking water treatment because of several reasons. We describe briefly the present state of membrane filtration processes for drinking water treatment in Japan: including background, objectives, membrane suppliers, and some cases of actual plants.