• Title/Summary/Keyword: Water loss

Search Result 3,685, Processing Time 0.026 seconds

Effects of Nozzle Diameter on Performance Characteristics for a Tangential Impeller-type Water Meter (접선류 임펠러형 수도미터의 노즐직경이 성능특성에 미치는 영향)

  • Suh, Sang-Ho;Lee, Byung-Ho;Cho, Min-Tae;Roh, Hyung-Woon
    • The KSFM Journal of Fluid Machinery
    • /
    • v.2 no.3 s.4
    • /
    • pp.59-66
    • /
    • 1999
  • In this study the effects of nozzle diameter on the performance characteristics for the tangential impeller-type water meter are studied experimentally. The nozzle is cut along the tangential direction of the inner case in the water meter. The nozzle shape is round and the number of nozzles used for the experimental study are 8. The performance characteristics are discussed for various nozzle diameters such as 3.1, 3.3, 3.5, 4.0, 4.5 and 5.0 mm. Among the tangential impeller-type water meters, the water meter with the nozzle diameter of 5.0 mm shows the least pressure loss and the instrumental error compared to the Korean Standards.

  • PDF

A Flow Quantity Distribution Characteristics of the Hot Water Header for Individual Room Control System (실별제어 온수분배기의 유량분배 특성)

  • Sung, Sun-Kyung
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.20 no.3
    • /
    • pp.175-180
    • /
    • 2008
  • Flow quantity to supply to a coil in floor heating system is important to achieve comfortable indoor air condition in the winter season. The hot water header is used to distribute the water into the coil. Experimental study has been performed using the water header that have 5 branches consisted of flow control valves and automatic shut-off valves. Each branch line connected it with X-L pipe. Experimental tests accomplished it to investigate the flow distribution characteristics of the hot water header. Experimental results show that the selection of the pump head and differential pressure are very important to save running energy of the system, and high differential pressure needs more friction loss in the case of suitable differential pressure for balancing of the header.

Why the Mediterranean Sea Is Becoming Saltier

  • Bryden, Harry-L.;Boscolo, Roberta
    • Journal of the korean society of oceanography
    • /
    • v.37 no.3
    • /
    • pp.117-124
    • /
    • 2002
  • Anthropogenic changes have been made to the water budget for the Mediterranean Sea as a result of river diversion projects. The decrease in freshwater inflow to the Mediterranean represents an effective increase in the overall net evaporation over the basin. Hydraulic control models for the exchange between the Mediterranean and Atlantic through the Strait of Gibraltar predict that the salinity of the Mediterranean should increase if the net evaporation over the Mediterranean increases. Increases in the salinity of the deep waters in both the western and eastern Mediterranean basins have been observed. The causes of such higher deep water salinity are attributed to increases in intermediate water salinity which are ultimately mixed down into the deep sea during wintertime buoyancy loss events. The pattern of the Mediterranean salinity increase is instructive for understanding how the water mass properties in a basin change over time as a result of anthropogenic changes.

Reactive Dyeing in Immixcible Two-phase System of Water/organic Solvent (I) (물/유기용매 불혼합 이성분계에서의 반응염색(I))

  • 김태경;윤석한;임용진;조광호
    • Textile Coloration and Finishing
    • /
    • v.13 no.1
    • /
    • pp.55-60
    • /
    • 2001
  • Cotton fabric was deed with a reactive dye in water/dichloromethane two-phase immiscible solvent media. In order to minimize dye loss due to its hydrolysis, the reactive dyeing was carried out in dichloromethane containing a small amount of water. With only 2ml of water in 23m1 of dichloromethane, 1.0g of cotton fabric could be dyed perfectly. The uptake ratio was increased greatly, compared with that of normal reactive dyeing in a waters medium. It would seem that the one of hydrophobic solvents, dichloromethane, can assist the eden dyeing as it disperses a small amount of dye-dissolved water phase and conveys this water phase to the fabric entirely and uniformly.

  • PDF

Pressure Wave Propagation in the Discharge Piping with Water Pool

  • Bang Young S.;Seul Kwang W.;Kim In-Goo
    • Nuclear Engineering and Technology
    • /
    • v.36 no.4
    • /
    • pp.285-294
    • /
    • 2004
  • Pressure wave propagation in the discharge piping with a sparger submerged in a water pool, following the opening of a safety relief valve, is analyzed. To predict the pressure transient behavior, a RELAP5/MOD3 code is used. The applicability of the RELAP5 code and the adequacy of the present modeling scheme are confirmed by simulating the applicable experiment on a water hammer with voiding. As a base case, the modeling scheme was used to calculate the wave propagation inside a vertical pipe with sparger holes and submerged within a water pool. In addition, the effects on wave propagation of geometric factors, such as the loss coefficient, the pipe configuration, and the subdivision of sparger pipe, are investigated. The effects of inflow conditions, such as water slug inflow and the slow opening of a safety relief valve are also examined.

MF Membrane Application for Water Treatment in Japan

  • Okazaki, Minoru
    • Proceedings of the Membrane Society of Korea Conference
    • /
    • 1995.10a
    • /
    • pp.80-93
    • /
    • 1995
  • Membrane Technology, which has been in use for over twenty five years, has established itself as one of the principle separation methods. With improved technology, Reverse Osmosis ("RO") has been applied to large volume water treatment facilities. UF and MF Membrane Technology has, up until recently, been applied to small scale water treatment facilities. The fouling of membrane has restricted the growth of Membrane Technology in Water Treatment. Membrane fouling compound found in water causes the loss of flux across the membrane by absorbing to membrane and plugging their pores. Various methods have been used in the reduction and prevention of membrane fouling. For RO, a conventional pre-treatment system removes the pollutants, preventing the function decline of RO membrane by keeping SDI < 4 as the standard condition of feed water. UF and MF Membrane Technology that must have pre-treatment function within itself, are required to keep its ability not to be influenced by fouling.y fouling.

  • PDF

Excess Pore Water Pressure Calculation Methods due to Gas Hydrate Dissociation (가스 하이드레이트의 해리로 발생하는 간극수압의 계산방법)

  • Park, Sung-Sik
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2008.10a
    • /
    • pp.888-892
    • /
    • 2008
  • If gas hydrate dissociates due to natural and/or human activities, it generates large amount of gas and water. Upon gas hydrate dissociation, a generated pore water pressure between soil particles increases and results in the loss of an effective stress and degradation of soil stiffness and strength. In order to predict the generated excess pore water pressure due to gas hydrate dissociation, two methods based on small hydrate concept (SHC) and large hydrate concept (LHC) are proposed. An excess pore water pressure generated by the gas hydrate dissociation in the Storegga Slide was calculated using two proposed methods.

  • PDF

Effects of a Weight Loss Program on Body Composition and Resting Energy Expenditure according to UCP 2 Genotype in Overweight Subjects

  • Shin, Ho-Jeung;Cho, Mi-Ran;Lee, Hye-Ok;Kim, Young-Sul;Ryowon Choue
    • Nutritional Sciences
    • /
    • v.5 no.4
    • /
    • pp.221-227
    • /
    • 2002
  • The objective of this study was to examine the effects of a weight loss program on the degree of obesity and levels of resting energy expenditure (REE) in overweight subjects according to their mitochondrial uncoupling protein 2 (UCP 2) genotype. Twenty-three subjects with a body mass index (BMI) greater than 27 were recruited from the Obesity Clinic of the Kyung-Hee University Hospital during the period of December 2000 - August 2001. The subjects were genotyped for the exon 8 allele; 15 subjects were found to be of del/del genotype, 8 were del/ins, and none were of ins/ins genotype. No significant association was found between the different UCP 2 genotypes and the initial levels of weight, fat mass (FM), lean body mess (LBM), BMI, REE, and REE/LBM ratio. After 12 weeks of a weight loss program, body weight and FM were significantly decreased, while LBM, total body water (TBW), and REE were not changed, irrespective of UCP 2 genotype. Initial fasting plasma levels of albumin, glucose, triglyceride, lipoprotein cholesterol, insulin, free triiodo-thyronine (T3), free fatty acid (FFA), and leptin were not different according to the UCP 2 genotype; furthermore, these blood parameters were not changed after the 12-week weight loss program. However, plasma levels of leptin decreased in both the del/del and ins/del genotypes, from 18.7 ng/ml to 13.4 ng/ml (p<.05), and from 18.1 ng/ml to 13.9 ng/ml (p<.05), respectively, after the weight loss program. In conclusion, this study found no significant association between the del/del or del/ins UCP 2 genotypes and differing levels of REE or differing degrees of obesity, either before or after a weight loss program. This study provided evidence that a well- managed weight loss program could maintain levels of REE, which plays an important role in the maintenance of energy balance.

Korean Red Ginseng extract treatment prevents post-antibiotic dysbiosis-induced bone loss in mice

  • Ho Jun Kang;Nicholas Chargo;Soumya Chennupati;Kerri Neugebauer;Jae Youl Cho;Robert Quinn;Laura R. McCabe;Narayanan Parameswaran
    • Journal of Ginseng Research
    • /
    • v.47 no.2
    • /
    • pp.265-273
    • /
    • 2023
  • Background: The intestinal microbiota is an important regulator of bone health. In previous studies we have shown that intestinal microbiota dysbiosis, induced by treatment with broad spectrum antibiotics (ABX) followed by natural repopulation, results in gut barrier dysfunction and bone loss. We have also shown that treatment with probiotics or a gut barrier enhancer can inhibit dysbiosis-induced bone loss. The overall goal of this project was to test the effect of Korean Red Ginseng (KRG) extract on bone and gut health using antibiotics (ABX) dysbiosis-induced bone loss model in mice. Methods: Adult male mice (Balb/C, 12-week old) were administered broad spectrum antibiotics (ampicillin and neomycin) for 2 weeks followed by 4 weeks of natural repopulation. During this 4-week period, mice were treated with vehicle (water) or KRG extract. Other controls included mice that did not receive either antibiotics or KRG extract and mice that received only KRG extract. At the end of the experiments, we assessed various parameters to assess bone, microbiota and in vivo intestinal permeability. Results: Consistent with our previous results, post-ABX- dysbiosis led to significant bone loss. Importantly, this was associated with a decrease in gut microbiota alpha diversity and an increase in intestinal permeability. All these effects including bone loss were prevented by KRG extract treatment. Furthermore, our studies identified multiple genera including Lactobacillus and rc4-4 as well as Alistipes finegoldii to be potentially linked to the effect of KRG extract on gut-bone axis. Conclusion: Together, our results demonstrate that KRG extract regulates the gut-bone axis and is effective at preventing dysbiosis-induced bone loss in mice.

Effects of Freezing Temperature on Quality of Thawed Beef (동결온도가 해동 쇠고기의 품질에 미치는 영향)

  • 남주현;송형익;김미숙;문윤희;정인철
    • The Korean Journal of Food And Nutrition
    • /
    • v.11 no.5
    • /
    • pp.482-487
    • /
    • 1998
  • This study was carried out to investigate the effects of freezing temperature on quality of thawed beef loin. In case of thaw drip loss, the freezing of -3$^{\circ}C$ and -2$0^{\circ}C$ were higest by 3.4% to 30 days and by 1.8% to 60 days, respectively. And the thaw drip loss of -3$^{\circ}C$ freezing was more than -2$0^{\circ}C$ freezing. The cooking loss of water bath and pan boiling were increased significantly during freezing than the beginning of freezing, but were not different -3$^{\circ}C$ and -2$0^{\circ}C$. The salt soluble protein extractability was decreased during freezing, the -2$0^{\circ}C$ freezing was higher than -3$^{\circ}C$ freezing. The water soluble protein extractability of -3$^{\circ}C$ freezing was not significant different during freezing storage, that freezed at -2$0^{\circ}C$ was increased during freezing. The "L" value of the beginning of freezing was higher than during freezing, the "a" value was not different during freezing, and the "b" value during freezing was higher than the beginning of freezing. The myoglobin denatured percentage of the -3$^{\circ}C$ and -2$0^{\circ}C$ freezing were highest by 94.4% to 45 days and by 94.0% to 15 days, respectively. The shear force value during freezing was higher than the beginning of freezing, the myofibrillar fragmentation index was not significant different during freezing. The pH was increased to freezing 30 days, after that was decreased.ays, after that was decreased.

  • PDF