• Mass Spectrometry Letters
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• 제3권3호
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• pp.78-81
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• 2012

The hydrophobic hydrocarbon chain and the polar sulfate group confer surfactant properties and enable them to be used as anionic surfactants. Anionic surfactants (AS) are known for their adverse impact on environment, particularly on aquatic ecosystem. In the present study a fast, sensitive and selective method for the determination and subsequent quantification of six anionic surfactants was developed using hydrophilic interactive liquid chromatography (HILIC) coupled to a electrospray ionization (ESI) mass spectrometer (MS), in the concentration range 15-20 ${\mu}g/L$. The capability of the method was established using regression analysis and ANOVA. The method performance was evaluated by analyzing real time surface water spiked with 1-dodecyl hydrogen sulfate at 15 ${\mu}g/L$. Combined efficiency of solid phase extraction and MS detection established recovery of 89% in presence of natural matrix. These results point out that HILIC coupled to multistage MS procedures can be a powerful technique for environmental applications concerning the screening of polar contaminants.

• 한국대기환경학회지
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• 제30권5호
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• pp.461-476
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• 2014

Continuous Water-Soluble Organic Carbons (WSOC) by the Particle Into Liquid Sampler - Total Organic Carbon (PILS-TOC) analyzer were measured at the Seoul intensive monitoring site from June 17 through July 5 in 2014. In addition, the 24 hour integrated PM2.5 collected by Teflon and Quartz filters were analyzed for water soluble ions by Ion chromatography (IC), WSOC by TOC from water extracts, organic carbon (OC), elemental carbon (EC) by carbon analyzer using the thermal optical transmittance (TOT) method, and mass fragment ions (m/z) related to alkanes and PAHs (Poly Aromatic Hydrocarbons) by Gas Chromatography-Mass Spectrometer-Thermal Desorption (GC/MS-TD). Based on the statistical analysis, four different Carbonaceous Thermal Distributions (CTDs) from OCEC thermal-gram were identified. This study discusses the primary and secondary sources of WSOC based on the Classified CTD, organic mass fragments, and diurnal patterns of WSOC. The results provide knowledge regarding the origins of WSOC and their behaviors.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.285-289
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• 2004

Oceanographic observation and qualitative analysis for deep ocean water in the East Sea were carried out from January 2003 to January 2004, in order to understand the characteristics of deep sea water in the East Sea. Temporal and spatial variation of water masses were discussed from survey of the study area including the coastal sea of Kwangwon province in where the polar front mixing cold and warm water masses were formed. On the basis of the vertical profiles of temperature, salinity and dissolved oxygen, water masses in the study area were divided into 5 major groups; (1) Low Saline Surface Water (LSSW) (2) Tsushima Surface water (TSW) (3) Tsushima Middle Water (TMW) (4) North Korea Cold Water (NKCW) and (5) East Sea Proper Water (ESPW). In winter, surface water in coastal sea of Kwangwaan Kosung region were dominated by North Korean Cold Water (NKCW). As Tsushima warm current were enforced in summer, various water masses were vertically emerged in study area, in order of TSW, TMW, NKCW and ESPW. It is highly possible that the LSSW which occurred at surface water of september is originated from influx of fresh water due to the seasonal rainy spell. Nevertheless water masses existed within surface water were seasonally varied, water quality characteristics of East Sea Proper Water (ESPW) under 300 m did not changed all the seasons of the year.

• 한국대기환경학회지
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• 제22권5호
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• pp.701-711
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• 2006

Sewage treatment plants located near to large cities emit extremely higher concentration of odorous materials. This study evaluated flux profiles of ammonia emitted from the water surface of sewage treatment plants using a dynamic flux chamber. Also, an ammonia overall mass transfer coefficient and a mass transfer model was developed in order to estimate fluxes of ammonia using environment parameters and the flux from the sewage treatment plants. The developed mass transfer model was evaluated through a fitness analysis. Comparison modeled flux applying empirical overall mass transfer coefficients of ammonia and measured ammonia flux show a high linearity with 0.977. The flux ratio of 1.282 demonstrated highly statistical fitness, also. Modeled flux using the mass transfer model was compared with measured flux. In result, it indicated that empirical overall mass transfer coefficients were similar to measured flux. The mass transfer model using the empirical overall mass transfer coefficient developed in this study was proved to be an easy and effective method to make accurate and precise predictions for ammonia flux discharged from sewage treatment plants.

• 한방재활의학과학회지
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• 제19권3호
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• pp.91-100
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• 2009

Objectives : The purpose of this study was to find the characteristics of Sasang Constitution, Soeumin, Soyangin and Taeumin, Using Regular Medical Inspection. Methods : Subjects of our study were 325 cases who took regular medical inspection. We collected the data of body composition analysis, 7-zone-diagnostic system, blood analysis, and analyzed by Sasang Constitution, Soeumin, Soyangin and Taeumin. Results and Conclusions : 1. In body composition analysis, Taeumin was significantly higher than Soeumin and Soyangin about soft lean mass, body fat mass, waist-hip ratio, body water index, body mass index and basal metabolic rate. In blood analysis, Taeumin was significantly highest about total protein, albumin, GPT, hemoglobin, WBC, triglyceride. In 7-zone-diagnostic system, Taeumin had the highest level at Zone 1, 2. 2. Taeumin had more significant differences than other Sasang constitutions about the parameters of regular medical inspection. 3. Body composition analysis had the most parameters that showed differences among the constitutions, followed by blood analysis and 7-zone-diagnostic system.

• 한국태양에너지학회 논문집
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• 제25권3호
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• pp.27-35
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• 2005

In this paper, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system with water-LiBr-LiSCN mixture which utilizes solar energy as evaporator heat source. In addition, a comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

• 상하수도학회지
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• 제28권5호
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• pp.589-600
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• 2014

Tuberculation and slime accumulated in water mains play an important role in modifying water quality of drinking water. Therefore, in this study, it was investigated that what materials were accumulated, and what components were included in the tuberculation and slime of water mains. The Various tuberculation and slime sample were collected from the 12 water mains to analyze their physical and chemical properties and crystal structure. As a analysis method, VSS(Volatile suspended solid), SEM(scanning electron microscope), EDS(Energy Dispersive X-ray spectroscope), ICP(Inductively Coupled Plasma Mass Spectrometer) and XRD(X-Ray Diffractomete) were used. The results of analysis on the samples, the representative materials were verified such as iron corrosion products, the fine sand particles generated during backwash, fine particles of activated carbon, aluminum used in coagulation process, and manganese included in raw water.

• 대한한방소아과학회지
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• 제28권2호
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• pp.1-22
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• 2014

Objectives The purpose of this study is to investigate the relationship between weak children and growth indices. Methods One hundred twenty-six of the first and the second grade elementary school students who didn't have to develop yet their secondary sexual characteristics answered the questionnaire. Their bone age and body composition were measured. Results 1. According to the Weak Children questionnaire analysis, respiratory problem was one of the biggest problems in the weak children group (35.7%), followed by digestive problems (23.0%), psycho-neurological problems (22.2%), neuromotor problems (9.5%), and urogenital problems (8.7%). 2. From the comparison between growth indices of weak children and that of normal children are as follows: 1) The group of children who had problem in their digestive system had lower growth indices than the normal average children group. The growth indices includes mean height, weight, total body water, protein mass, mineral mass, body fat, skeletal muscle mass, body fat percentage, body mass index (BMI), and basal metabolic rate (BMR). 2) The children who had urogenital weakness had lower mean height, RH (Recent Height), RH - MPH {Recent Height(%) - Mid-Parental Height(%)}, RUS (Radius, Ulna and Short bone) score, weight, protein mass, body fat, BMI, and visceral fat than the normal children group. 3. The results of the multiple comparisons of growth indices and weak children groups are as follows: 1) Digestive weak children were the lowest in total body water, protein mass, mineral mass, skeletal muscle mass, and basal metabolic rate. 2) Urogenital weak children were the lowest in height, RH, RH - MPH, RUS score, and weight. Conclusion These results showed that children's growth is strongly correlated to their own growth problems, especially to those children who have digestive and urogenital problems. Therefore, this may be an effective way for children growth treatment in Korean medicine to treat weak symptoms.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.345-348
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• 1999

Since the cement-water reaction is exothermic by nature, the temperature rise within a large concrete mass. Significant tensile stresses may develop from the volumn change associated with the increase and decrease of the temperature with the mass concrete. These thermal stresses will cause temperature-related cracking in mass concrete structures. These typical type of mass concrete include mat foundation, bridge piers, thich walls, box type walls, tunnel linings, etc. Crack control methods can be considered at such stages as designing, selecting the materials, and detailing the construction method. In this paper, the effect of placing of crack control joint or construction joint was analysed by a three dimensional finite element method. As a result, using this method, crack control can be easily performed for structures such as wall-type structures.

• Membrane and Water Treatment
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• 제4권4호
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• pp.251-263
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• 2013

The internal reflux effect on dialysis through the retentate phase of a countercurrently cross-flow rectangular module is investigated. Theoretical analysis of mass transfer in cross-flow devices with or without recycling is analogous to heat transfer in cross-flow heat exchangers. In contrast to a device without reflux, considerable mass transfer is achievable if cross-flow dialyzers are operated with reflux, which provides an increase in fluid velocity, resulting in a reduction in mass-transfer resistance. It is concluded that reflux can enhance mass transfer, especially for large flow rate and feed-concentration operated under high reflux ratio.