• Title/Summary/Keyword: Mass-estimation

검색결과 780건 처리시간 0.027초

Hydrogeochemical Research on the Characteristic of Chemical Weathering in a Granitic Gatchment (水文化學的 資料를 통한 花崗岩質 流域의 化學的 風化特性에 關한 硏究)

  • Park, Soo-Jin
    • Journal of the Korean Geographical Society
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    • 제28권1호
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    • pp.1-15
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    • 1993
  • This research aims to investigate some respects of chemical weathering processes, espcially the amount of solute leaching, formation of clay minerals, and the chemical weathering rate of granite rocks under present climatic conditions. For this purpose, I investigated geochemical mass balance in a small catchment and the mineralogical composition of weathered bedrocks including clay mineral assemblages at four res-pective sites along one slope. The geochemical mass blance for major elements of rock forming minerals was calculated from precipitation and streamwater data which are measured every week for one year. The study area is a climatically and litholo-gically homogeneous small catchment($3.62Km^2$)in Anyang-shi, Kyounggi-do, Korea. The be-drock of this area id Anyang Granite which is composed of coarse-giained, pink-colored miner-als. Main rock forming minerals are quartz, K-Feldspar, albite, and muscovite. One of the chracteristics of this granite rock is that its amount of Ca and Mg is much lower than other granite rock. The leaching pattern in the weathering profiles is in close reltion to the geochemical mass balance. Therefore the removal or accumulation of dissolved materials shows weathering patterns of granite in the Korean peninsula. Oversupplied ions into the drainage basin were $H^+$, $K^+$, Fe, and Mn, whereas $Na^2+$, $Mg^2+$, $Ca^2+$, Si, Al and $HCO-3^{-}$ were removed from the basin by the stream. The consumption of hydrogen ion in the catchment implies the hydrolysis of minerals. The surplus of $K^+$ reflects that vegetation is in the aggravation stage, and the nutrient cycle of the forest in study area did not reach a stable state. And it can be also presumed that the accumulation of $K^+$ in the top soil is related to the surplus of $K^+$. Oversupplied Fe and Mn were presumed to accumulate in soil by forming metallic oxide and hydroxide. In the opposite, the removal of $Na^+$, Si, Al resulted from the chemical weathering of albite and biotite, and the amount of removal of $Na^+$, Si, Al reflected the weathering rate of the bedrock. But $Ca^2+$ and $Mg^2+$ in stream water were contaminated by the scattered calcareous structures over the surface. Kaolinite is a stable clay mineral under the present environment by the thermodynamical analysis of the hydrogeochemical data and Tardy's Re value. But this result was quite different from the real assemblage of clay miner-als in soil and weathered bedrock. This differ-ence can be explained by the microenvironment in the weathering profile and the seasonal variation of climatic factors. There are different clay forming environments in the stydy area and these differences originate from the seasonal variation of climate, especially the flushing rate in the weathering profile. As it can be known from the results of the analysis of thermodynamic stability and characteristics of geochemical mas balance, the climate during winter and fall, when it is characterized by the low flushing rate and high solute influx, shows the environmental characteristics to from 2:1 clay minerals, such as illite, smectite, vermiculite and mixed layer clay minerals which are formed by neoformation or transformation from the primary or secondary minerals. During the summer and spring periods, kaoli-nite is a stable forming mineral. However it should consider that the other clay minerals can transformed into kaolinite or other clay minerals, because these periods have a high flushing rte and temperature. Materials which are directly regulated by chemical weathering in the weathered bedrock are $Na^+$, Si, and Al. The leaching of Al is, however, highly restricted and used to form a clay mineral, and that of Si falls under the same category. $Na^+$ is not taked up by growing veget ation, and fixed in the weathering profile by forming secondary minerals. Therefore the budget of $Na^+$ is a good indicator for the chemical weathering rate in the study area. The amount of chemical weathering of granite rocks was about 31.31g/$m^2+$/year based on $Na^+$ estimation.

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Comparison of the Estimations of Body Fat by Bioelectrical Impedence Analysis(BIA) and Anthropometric Measurements of Elementary School Students in Daejeon (대전 시내 초등학생의 생체 전기 임피던스치와 신체계측치에 의한 체지방율 비교 연구)

  • Wang, Soo-Gyoung;Lee, Na-Young
    • Korean Journal of Human Ecology
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    • 제16권4호
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    • pp.849-854
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    • 2007
  • Body fat proportion is a major issue in health. The prevalence of obesity in childhood has been increasing on thesedays. A series of indirect estimates of body fat have been developed. There are hydrodensitometry, BIA and anthropometry equation for body fat. Hydrodensitometry has been regarded as a common criterion method. BIA made it possible to analyze body fat mass more related to hydrodensitometry than anthropometry. The purpose of this unvestigation were to compare body fat and other body composition between boys & girls and to know which anthropometry equation for body fat was most closely associated with BIA in boys & girls respectively. The subjects were 148 4th grade elementary school students(male:70, female:78). They underwent BIA(InBody 3.0, Biospace Korea)to determine body fat and other body composition. Anthropometric measurements were taken of height, weight, skinfolds and circumferences. The results obtained are summarized as follow: 1) Weight, BMI and Rohrer index were $39.9{\pm}7.2kg$, $20.5{\pm}8.0$, $138.2{\pm}17.0$ for boys and $35.9{\pm}6.7kg$, $18.2{\pm}2.6$, $96.6{\pm}13.6$ for girls. 2) Total body fat and percent body fat determined by BIA were $10.3{\pm}4.3kg$, $25.4{\pm}6.6%$ for the boys group and $9.3{\pm}3.8kg$, $25.1{\pm}6.0%$ for girls. 3) Mean triceps skinfold thickness was $20.5{\pm}6.1mm$ in boys, $17.0{\pm}5.1mm$ in girls and mean WHR was $0.88{\pm}0.4$ in bodys, $0.82{\pm}0.4$ in female and the values were significantly different by sex. 4) Correlational nanlyses showed that estimation of body fat by BIA measurement seemed to be closely associated with Rohere index(boys r=0.854, girls r=0.909). Kim's equation was highly correlated with the body fat in girls(r=0.910) but less correlated in boys(r=0.710). We need to develop specific anthropometric equations based on age and sex to determine body fat for children.

Estimation of the Deformation Modulus for a Fault Zone using Crown Settlements Measured During Tunnel Excavation (터널 굴착 중 측정된 천단변위를 이용한 단층대의 변형계수 산정)

  • Yun, Hyun-Seok;Moon, Seong-Woo;Song, Gyu-Jin;Seo, Yong-Seok;Kim, Ji-Soo;Woo, Sang-Baik
    • The Journal of Engineering Geology
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    • 제24권2호
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    • pp.227-235
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    • 2014
  • The deformation modulus is one of the essential factors in determining ground behavior and safety during tunnel excavation. In this study, we conducted a back-analysis using crown settlements measured during tunnel excavation, using a horizontal inclinometer on a fault zone of pegmatite, and calculated the deformation modulus of the fault zone. This deformation modulus calculation was then compared with deformation moduli found through established relationships that use the correlation between RMR and the deformation modulus, as well as the results of pressure-meter tests. The deformation moduli calculated by back-analysis differs significantly from the deformation moduli determined through established relationships, as well as the results from pressure-meter tests conducted across the study area. Furthermore, the maximum crown settlements derived from numerical analysis conducted by applying deformation moduli determined by these established relationships and the pressure-meter tests produced noticeable differences. This result indicates that in the case of a weak rock mass, such as a fault zone, it is inappropriate to estimate the deformation modulus using preexisting relationships, and caution must be taken when considering the geological and geotechnical characteristics of weak rock.

The Ratooning Potential of Several Early-Ripening Rice Cultivar in Korea (조생종 벼의 움벼(ratoon-rice)생산 및 움벼의 생육특성)

  • Shin, Jong-Hee;Kim, Sang-Kuk;Park, Sang-Gu
    • KOREAN JOURNAL OF CROP SCIENCE
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    • 제60권2호
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    • pp.139-145
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    • 2015
  • Rice ratooning is the production of a second rice crop from the stubble left behind after the main-crop harvest. The main advantage of rice ratooning is that in areas where rice is the main crop, double crop of rice can be grown for additional returns. Eight cultivars of rice were tested for estimation their ratooning ability. The main crop was harvested at mass maturity, after which the tillers were mowed to stubbles of about 10 cm tall. And then left without any further input, until the ratooned plant were ready for harvest. Highly significant variations were detected in the ratoon performance among cultivars, with ratoon ability ranging from 0% ('Unkwang', 'Jopeyong', 'Odae', 'Nokyang') to 33% ('Jinbuol') in their grain yield. The maximum grain yield from ratoon rice was 202 and 203 kg/10a for 'Jinbuol' and 'Joun' followed by 'Junamjoseng' 174kg/10a. Protein and amylose contents of ratoon rice were more increased than those of main rice. The platability value of cooked rice of ratoon was lower than that of main crop. Germination rate of the previous year's harvest of rice was not significantly different between ratoon and main crop. This rice ratooning system requires short duration, creating possibility for growing another crop in the same cropping year and offers an opportunity to increase cropping intensity per unit of cultivated areas.

A Study on Punch Penetration Test for Performance Estimation of Tunnel Boring Machine (TBM의 굴진성능 예측을 위한 압입시험에 대한 연구)

  • Jeong, Ho-Young;Jeon, Seok-Won;Cho, Jung-Woo
    • Tunnel and Underground Space
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    • 제22권2호
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    • pp.144-156
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    • 2012
  • This paper discusses the methods of estimating the punch penetration indices and data analysis punch penetration test to estimate the TBM normal force and penetration rate. In punch penetration test is known as a useful test to estimate penetration rates and normal force of TBMs directly with several slope indices indicated drill-ability and brittleness of rocks. However, the standard methods and indices for punch penetration test are not suggested yet. The main purpose of punch penetration test which is prediction of normal force of TBM disc cutter when cutters excavate rock mass. In this study, the punch penetration tests were performed for 6 representative Korean rock types and variety length and diameter of rock core specimens. Among slope indices were obtained from punch penetration test, PLI and MLI which is suggested in this study show high correlation with cutter force measured by full-scale cutting test. The results show that the predicted normal force of a single disc cutter and the experimental error was 10%. Based on these results, it is concluded that punch penetration test is reliable laboratory test for estimating thrust and penetration rates of TBM.

Diabetes Mellitus and Site-specific Colorectal Cancer Risk in Korea: A Case-control Study

  • Woo, Hyeongtaek;Lee, Jeeyoo;Lee, Jeonghee;Park, Ji Won;Park, Sungchan;Kim, Jeongseon;Oh, Jae Hwan;Shin, Aesun
    • Journal of Preventive Medicine and Public Health
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    • 제49권1호
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    • pp.45-52
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    • 2016
  • Objectives: Previous large-scale cohort studies conducted in Korea have found a positive association between diabetes mellitus (DM) and colorectal cancer (CRC) in men only, in contrast to studies of other populations that have found significant associations in both men and women. Methods: A total of 1070 CRC cases and 2775 controls were recruited from the National Cancer Center, Korea between August 2010 and June 2013. Self-reported DM history and the duration of DM were compared between cases and controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by binary and polytomous logistic regression models. Results: DM was associated with an elevated risk of CRC in both men (OR, 1.47; 95% CI, 1.13 to 1.90) and women (OR, 1.92; 95% CI, 1.24 to 2.98). This association remained when we controlled for age, body mass index, alcohol consumption, and physical activity level. In sub-site analyses, DM was associated with distal colon cancer risk in both men (multivariate OR, 2.04; 95% CI, 1.39 to 3.00) and women (multivariate ORs, 1.99; 95% CI, 1.05 to 3.79), while DM was only associated with rectal cancer risk in women (multivariate OR, 2.05; 95% CI, 1.10 to 3.82). No significant association was found between DM and proximal colon cancer risk in either men (multivariate OR, 1.45; 95% CI, 0.88 to 2.41) or women (multivariate OR, 1.79; 95% CI, 0.78 to 4.08). Conclusions: Overall, DM was associated with an increased risk of CRC in Koreans. However, potential over-estimation of the ORs should be considered due to potential biases from the case-control design.

Development of Shielding using Medical Radiological Contrast Media; Comparison Analysis of Barium Sulfate Iodine Shielding ability by Monte Carlo Simulation (의료방사선 조영제를 이용한 차폐체 개발; 몬테카를로 시뮬레이션을 통한 황산바륨과 요오드의 차폐능 비교분석)

  • Kim, Seon-Chil
    • Journal of the Korean Society of Radiology
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    • 제11권5호
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    • pp.329-334
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    • 2017
  • The purpose of this study is to estimating the possibility of manufacturing radiation shielding sheet by searching for environmentally friendly materials suitable for medical environment of medical radiation shielding. There are many tungsten products which are currently used as shielding materials in place of lead, but there are small problems in the mass production of lightweight shielding sheets due to economical efficiency. To solve these problems, a lightweight, environmentally friendly material with economical efficiency is required. In this study, Barium sulphate and Iodine were proposed. Both materials are already used as contrast medias in radiography, and it is predicted that the shielding effect will be sufficient in a certain region as a shielding material because of the characteristic of absorbing radiation. Therefore, in this study, we used a Monte Carlo simulation to simulate radiation shielding materials. When it is a contrast agent such as Barium sulfate and Iodine, the radiation absorption effect in the high energy region appears greatly, and the effectiveness of the two shielding substance in the energy region of the star with thickness of 120 kVp is also evaluated in the medical radiation imaging region. Simulated estimation results it was possible to estimate the effectiveness of shielding for all two substances. Iodine has higher shielding effect than barium sulfate, 0.05 mm thick appears great effect. Therefore, the Monte Carlo simulation confirms that iodine, which is a radiological contrast agent, is also usable as barium sulfate in the production of radiation shielding sheets.

Weight Control Behaviors, Health-related Quality of Life and Nutritional Status by Overestimation of Body Image among Young Korean Females: Data from the Fifth Korea National Health and Nutrition Examination Survey, 2010-2011 (20·30대 여성의 체형 과대인식에 따른 체중조절행위, 삶의 질, 식행동 및 영양소 섭취상태: 2010-2011년 국민건강영양조사 자료 이용)

  • Park, Seulki;Hyun, Taisun;Lee, Hongmie
    • Korean Journal of Community Nutrition
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    • 제20권5호
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    • pp.362-374
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    • 2015
  • Objectives: This study was performed to investigate the effects of overestimation of their own body shape on weight control behaviors, mental condition, physical activity, dietary behavior, health-related quality of life, and nutritional status among young Korean females. Methods: A total of 1,514 women aged 20-39 years who are not pregnant and lactating among those who participated in the Fifth Korea National Health and Nutrition Examination Survey (2010~2011), were analyzed and grouped into underestimation (n=120), normal estimation (NE, n=840), and overestimation (OE, n=554), based on their body perception compared to actual percent ideal body weights. Variables were compared between OE group and NE group. Results: The subjects in OE group were significantly younger (29.5 vs. 30.5 years, respectively p < 0.05) and had lower body mass index (20.9 vs. 22.2 respectively, p < 0.01), health-related quality of life measured by EQ-5D (EuroQol-5 Dimension)(0.97 vs. 0.98 respectively, p < 0.05), nutrition adequacy ratio (NAR) of protein (0.91 vs. 0.93 respectively, p < 0.05), phosphorous (0.93 vs. 0.96 respectively, p < 0.05), and iron (0.70 vs. 0.75 respectively, p < 0.01), and index of nutrition quality (INQ) of iron (0.84 vs. 0.89 respectively, p < 0.05) compared to those in the NE group. The results of logistic regression showed that unmarried status (OR 1.32; 1.01~1.72) and severely underweight/underweight status (OR 1.94; 1.01~3.75)/(OR 1.81; 1.34~2.45) were significantly related to the probability of overestimation by the subjects. Significantly more women in OE group practiced fasting, skipping meals, and taking prescribed pills to lose body weights and had skipped breakfast compared to those in the NE group. Conclusions: The results of this study suggested that the Korean young women's distorted perception of own body shape may be associated with undesirable weight control behavior, low quality of life, and lower nutritional status. Therefore, nutrition education for this group should include information on correct body shape perception and its importance.

Atmospheric Aerosol Optical Properties in the Korean Peninsula

  • Oh, Sung-Nam;Sohn, Byung-Ju;Chung, Hyo-Sang;Park, Ki-Jun;Park, Sang-Soon;Hyun, Myung-Suk
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 한국대기환경학회 2003년도 춘계학술대회 논문집
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    • pp.423-423
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    • 2003
  • The radiative properties of atmospheric aerosol are determined by the mass and chemical characteristics, and optical properties such as aerosol optical depth (AOD), ngstr m parameter ( $\alpha$) and single scattering albedo (SSA). In particular these aerosol optical properties also determine surface temperature perturbation that may give some information in understanding the regional atmospheric radiative forcing. For understanding the radiative forcing and regional surce of aerosol, this paper summarizes and compares the aerosol optical properties results from and compares the atmospheric aerosol optical properties results from two different experiments: Anmyeon 2000 and Jeju 2001. Korea Global Atmosphere Watch Observatory (KGAWO) at Anmyeon island and ACE-Asia super-site at Gosan Jeju island have measured the radiations and aerosols since the year of 2000. The sites are located in the mid-west and south of Korea peninsula where it is strongly affected by the Asian dust coming from China region in every spring. Aerosol optical properties over both sites were measured through the ground-based sun and sky radiometers were analyzed for understanding the radiation and climate properties. Number concentration and chemical components of aerosol were additionally analyzed for the source estimation in the transportation. The frequency distributions of aerosol optical depth are rather narrow with a modal vaiue of 0.38 at both sites. However, the distributions of show one peak (1.13) at Jeju but two peaks (0.63 and 1.13) at Anmyeon. In the cases of Anmyeon, one peak around 0.63 corresponds to relatively dust-free cases, and the second peak around 1.13 characterizes the situation when Asian dust is presented. The correlation between AOD and resulted high correlation on the wide range with high values of optical depth at Anmyeon, otherwise a narrow range of with moderate to low AOD at Jeju. In dust free condition SSA decrease with waveleneth while in the presence of Asian dust SSA either stays neutral or increases slightly with wavelength. The change of surface temperature shows the stronger positive correlations with aerosol optical depth increase at Anmyeon than Jeju. In the chemical properties the aerosol are related to high concentrations in inorganic matters, SO$^4$, NO$_3$, CA2+ in fine and coarse.

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A Path Analytic Exploration of Consumer Information Search in Online Clothing Purchases (온라인 의복구매를 위한 소비자 정보탐색의 경로분석적 탐구)

  • Kim, Eun-Young;Knight, Dee K.
    • Journal of the Korean Society of Clothing and Textiles
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    • 제31권12호
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    • pp.1721-1732
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    • 2007
  • This study identified types of information source, and explored a path model for consumer information search by shopping attributes in the context of online decision making. Participants completed self-administered questionnaires during regularly scheduled classes. A total of 219 usable questionnaires were obtained from respondents who enroll at universities in the southwestern region of the United States. For data analysis, factor analysis and path model estimation were used. Consumer information source was classified into three types for online clothing purchases: Online source, Offline retail source, and Mass media. Consumers were more likely to rely on offline retail source for online clothing purchases, than other sources. In consumer information search by shopping attributes, online sources were more likely to be related to transaction-related attributes(e.g., incentive service), whereas offline retail source(e.g., displays in stores, manufacturer's catalogs and pamphlets) were more likely to be related to product and market related attributes(e.g., aesthetics, price) when purchasing clothing online. Also, the path model emphasizes the effect of shopping attributes on traditional retailer search behavior, leading to online purchase intention for clothing. This study supports consumer information search by attributes, and discusses a managerial implication of multi-channel retailing for apparel.