• Title/Summary/Keyword: 75A size

Search Result 1,871, Processing Time 0.035 seconds

A Study on the Characteristics of Water Quality According to Particle Size Distribution of Sediments (하상퇴적물의 입도분포에 따른 수질특성에 관한 연구)

  • Park, Sung-Jin;Kim, Hwan-Gi
    • Journal of Korean Society of Water and Wastewater
    • /
    • v.23 no.1
    • /
    • pp.97-105
    • /
    • 2009
  • Analysis was done on the particle size distribution of sediments flown into Saemangeum from the Mankyung and Dongjin River. The organic pollutants and heavy metal existing in the sediments were analyzed, which was further used to study the properties of pollution in the sediments according to the particle size distribution. Conclusions shown below were made from these analyses. The particle size distribution showed a big difference between the upriver areas of Mankyung and Dongjin River. Particles under $75{\mu}m$ showed to be around 85% at Dongjin River, while it showed to be around 70% at Mankyung River. This kind of distribution in particle size concluded in greatly affecting the contamination density of the sediments. From the analysis done on the soil type of sediments, deposition in Mankyung River categorized into Silty loam and Sandy loam, where Silty loam covered most of area and deposition in Dongjin River categorized into Sand, Loamy sand, Silty loam, Sandy loam. Considering the weight ratio, the density of contamination of the sediments by particle size at Dongjin and Mankyung River has been analyzed to show that organic pollutants and heavy metals occupy more than 70% of the whole contamination in the range under the particle size of $75{\mu}m$.

Effects of the Pore Size of Graphite on the Mechanical Properties and Permeability of a Porous Nozzle for Continuous Casting Process

  • Cho, Yong-Ho;Kim, Juyoung;Yoon, Sanghyeon;Lee, Heesoo
    • Korean Journal of Metals and Materials
    • /
    • v.49 no.7
    • /
    • pp.530-534
    • /
    • 2011
  • To analyze the effect of the pore size of graphite in a pore-forming agent, graphite was added to porous ceramics of $Al_2O_3-SiO_2-ZrO_2$ systems. The graphite had 45~75, 100~125, 150~180, and 75~180${\mu}m$ dimensions. The properties of the ceramics, such as apparent porosity, density, dynamic elastic modulus, mechanical strength, and permeability, were investigated. The average pore size increased from 15.35${\mu}m$ to 22.32${\mu}m$ with the increase of the graphite size. The sample with the largest average pore size showed the highest mechanical strength and gas permeability. This was due to the sample with the largest pore size at the same porosity having fewer pores and larger distance between the pores than the sample with the smallest pore size, making cracks less likely to propagate. In addition, the large pore size reduced the repulsive power originating from the drag force between the gas and internal pore walls.

Clonal Propagation in Commiphora Wightii (Arnott.) Bhandari

  • Mishra, Dhruv Kumar;Kumar, Devendra
    • Journal of Forest and Environmental Science
    • /
    • v.30 no.2
    • /
    • pp.218-225
    • /
    • 2014
  • Studies were carried out to standardize and develop a suitable macro-propagation technology for large scale production of superior clonal stock through stem cuttings in Commiphora wightii Arnott (Bhandari), a data deficient medicinal plant of arid region. For the purpose, three experiments were conducted. The first experiment was tried to elucidate the impact of various cutting diameters (0.50-0.75 cm, 0.75-1.00 cm, 1.00-1.50 cm, and >1.50 cm) in combination with varying growing conditions (sunlight, shade house and mist chamber) on shoot sprouting and rooting without using exogenous plant growth regulators. Cutting diameter (size 0.75-1.00 cm) in mist chamber has shown maximum sprouting (90.00%) and rooting (73.33%), primary root (6.67) and secondary root (16.67) followed by 1.00-1.51 cm in mist chamber. Minimum sprouting (40.00%), rooting (33.33%), number of shoot (1.33), primary root (1.00) and number of secondary root (1.00) was recorded in cutting diameter (size >1.50 cm) in sunlight. Second experiment was performed to find out optimum growth regulator concentration of rooting hormone (100, 200, 500 and 1000 ppm) of Indole-3-acetic acid (IAA) and Indole-3-butyric Acid (IBA) on adventitious root formation on cuttings diameter (size 0.25-0.50 cm) in comparison to control. Maximum rooting percentage (93.33%) was recorded in 200 ppm followed by 500 ppm (86.66%) of IBA as compared to control, which showed only 60 per cent sprouting. Third experiment was performed with newly formed juvenile micro-cuttings treated with varying concentrations of IAA and IBA. The juvenile cuttings (size 6-10 cm, basal dia <0.25 cm) were selected as micro-cuttings. The cuttings treated with IBA (500 ppm) showed 64.30% rooting as compared to other treatments. Results of above experiments indicate that cuttings (size 0.75-1.00 cm dia) may be developed in mist chamber for better performance. While using heavier cuttings, no growth promoting hormones is required however; growth regulator 200 ppm concentration of IBA rooting hormone was observed optimum for promoting macro-propagation in stem cuttings of lower diameter class (0.25-0.50 cm).

Compression Strength Size Effect on Carbon-PEEK Fiber Composite Failing by Kink Band Propagation

  • Kim, Jang-Ho
    • KCI Concrete Journal
    • /
    • v.12 no.1
    • /
    • pp.57-68
    • /
    • 2000
  • The effect of structure size on the nominal strength of unidirectional fiber-polymer composites, failing by propagation of a kink band with fiber microbuckling, is analyzed experimentally and theoretically. Tests of novel geometrically similar carbon-PEEK specimens, with notches slanted so as to lead to a pure kink band (without shear or splitting cracks), are conducted. The specimens are rectangular strips of widths 15.875, 31.75. and 63.5 mm (0.625, 1.25 and 2.5 in and gage lengths 39.7, 79.375 and 158.75 mm (1.563, 3.125 and 6.25 in.). They reveal the existence of a strong (deterministic. non-statistical) size effect. The doubly logarithmic plot of the nominal strength (load divided by size and thickness) versus the characteristic size agrees with the approximate size effect law proposed for quasibrittle failures in 1983 by Bazant This law represents a gradual transition from a horizontal asymptote, representing the case of no size effect (characteristic of plasticity or strength criteria), to an asymptote of slope -1/2 (characteristic of linear elastic fracture mechanics. LEFM) . The size effect law for notched specimens permits easy identification of the fracture energy of the kink bandand the length of the fracture process zone at the front of the band solely from the measurements of maximum loads. Optimum fits of the test results by the size effect law are obtained, and the size effect law parameters are then used to identify the material fracture characteristics, Particularly the fracture energy and the effective length of the fracture process zone. The results suggest that composite size effect must be considered in strengthening existing concrete structural members such as bridge columns and beams using a composite retrofitting technique.

  • PDF

A Study on the Breast Shape Analysis of Big-breasted Women (볼륨 유방 여성의 흉부체형 분석에 관한 연구)

  • Han, ChoHee;Yi, Kyong-Hwa
    • Journal of Fashion Business
    • /
    • v.22 no.5
    • /
    • pp.32-40
    • /
    • 2018
  • Big breasted women often experience dissatisfaction with ready-made brassieres, that do not account for individual breast types nor provide adequate cup sizes. This study was conducted to provide basic information on common breast shape and measurements of Korean big-breasted women, and to facilitate development of big-breasted women's bras with excellent fit and comfort. The study analyzed direct upper body measurements of 178 women in their 20's whith cup size C or bigger in the 5th, 6th and 7th Size Korea. In addition, 3D body scan data of women with bra size 75 and cup size C were re-collected and their breast types were examined. Average under-bust circumference of big-breasted women was 75 size in brassiere size. The average stature was 159.78 cm and the body weight was 60.33kg, indicating "overweight". Also, it was revealed that common breast types of big-breasted women, were hemispheric and cone types. The study can facilitate better understanding of breast shapes and sizes of standard big-breasted women, and will be useful as reference in selection of subjects in future studies.

Effects of Template Size and Content on Porosity and Strength of Macroporous Zirconia Ceramics (기공형성제 크기와 함량이 다공질 지르코니아 세라믹스의 가공율과 강도에 미치는 영향)

  • Chae, Su-Ho;Kim, Young-Wook;Song, In-Hyuek;Kim, Hai-Doo;Bae, Ji-Soo
    • Journal of the Korean Ceramic Society
    • /
    • v.46 no.1
    • /
    • pp.35-40
    • /
    • 2009
  • Using zirconia and poly (methyl methacrylate-coethylene glycol dimethacrylate) (PMMA) microbeads, macroporous zirconia ceramics were fabricated by a simple pressing method. Effects of template size and content on microstructure, porosity, and flexural and compressive strengths were investigated in the processing of the macroporous zirconia ceramics. Three different sizes of microbeads (8, 20, and $50{\mu}m$) were used as a template for fabricating the macroporous ceramics. The porosity increased with increasing the template size at the same template content. The flexural and compressive strengths were primarily influenced by the porosity rather than the template size. However, the strengths increased with decreasing the template size at the same porosity. By controlling the template size and content, it was possible to produce macroporous zirconia ceramics with porosities ranging from 58% to 75%. Typical flexural and compressive strength values at 60% porosity were ${\sim}30\;MPa$ and ${\sim}75\;MPa$, respectively.

Picibanil Therapy for Lymphangioma (Picibanil을 이용한 림프관종의 치료 효과)

  • 손영익;장병찬;정재윤;백정환;김현학;이석구
    • Korean Journal of Bronchoesophagology
    • /
    • v.4 no.1
    • /
    • pp.96-100
    • /
    • 1998
  • Lymphangiomas are congenital malformations of the lymphatic system. Cervicofacial lymphangioma represents 75% of all lymphangiomas. Surgical excision has been the treatment of choice, however the reported results have been unsatisfactory. Various sclerosants have been tried to treat lymphangiomas, with variable results and considerable side effects. Herein we report the results of treatment using intralesional picibanil for lymphangioma. Between January 1996 and January 1998, 16 patients with lymphangiomas, 10 boys and 6 girls, were treated with intralesional picibanil injections. All cases were treated as a primary therapy. Eight lymphagiomas were located in the neck, and 2 in the cheek, 2 in the parotid, 2 in the trunk, 1 in the oropharynx, 1 in the thigh. Dose and method of intralesional injection was similar to that reported by Ogita in 1987. Complete regression was observed in 10 cases and marked regression(> 75% size decrease) in 2 cases and moderate regression(75%-25% size decrease) in 2 cases and poor regression(< 25% size decrease) in 2 cases. No serious side effect was observed except fever lasting for 2-3 days. Intralesional injection of picibanil for lymphangiomas represents a safe, easy and effective way of treatment with high success rate. Picibanil injection can be used as a primary therapy for lymphangiomas.

  • PDF

A study on the fabrication methods of rough diamond according to their shapes (bruting) (다이아몬드 원석의 외형에 따른 가공방법에 관한 연구(모형))

  • 최덕환;김세환;최종건
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.13 no.1
    • /
    • pp.46-50
    • /
    • 2003
  • This paper is a study on the method that it is bruting a peace of a rough diamond with keeping the maximum volume of it. When a diamond will be bruting, how to keep the maximum diameter of one is very important because of its own characteristics that include shapes, mineral characteristics, and so on. In the middle of bruting. concentrating on the work is also required because girdle will be break down. We tried to bruting with gaining maximum diameters of rough diamond. As the result. an octahedron is made into the round shape with size $6.75\times 6.75\times 3.83$ mm , a dodecahedron the cushion shape with size $6.86\times 6.86\times 3.95$mm , a fancy the marquise with size $6.92\times 3.78\times 3.46$mm . Their rates of loss are round brilliant 24.5%, cushion barion 15.5 %, and marquise 18.7 %, respectively.

Analysis of Body Size and Characteristics for Petite-size -Focused on Women Aged 18 to 34- (Petite-size의 신체 치수와 체형 특징 분석 -18~34세 여성을 중심으로-)

  • Lee, Jeong Yim
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.40 no.2
    • /
    • pp.330-341
    • /
    • 2016
  • This study suggested criterion for Petite-size and analyzed the body size and characteristics that were proper to manufacture clothing for Korean Petite-size women aged 18 to 34. It also analyzed size information about pattern making for Petite-size women through a comparison of the size and proportion of Petite-size with Regular-size. The criterion of Petite-size was decided in consideration of the distribution and perception of stature; subsequently, the stature range for Petite-size was defined as under 157.5cm. Body size and proportion of Petite-size were analyzed through calculating the mean from 25 to 75 percentiles of a Petite-size stature range. The Petite-size of this study was compared to KS Petite and total subjects through One way ANOVA. It was confirmed that the Petite-size of this study had body characteristics like KS Petite; however, Petite-size was larger in height and vertical length than KS Petite. The significant differences between Petite-size and Regular-size were identified in the same bust girth range, that required a revised calculation formula for pattern making that would be proper for Petite-size. It is expected that the Body size and proportion could be utilized as a reference for manufacturing or purchasing Petite-size clothing. The result of this study will contribute to enhance the fit satisfaction for Petite-size women aged 18 to 34.

Optimal O/D Sample Size Computation using link Volume Estimates (구간 교통량의 표준오차를 이용한 최적 O/D 표본수 산출)

  • 윤성순;김원규
    • Journal of Korean Society of Transportation
    • /
    • v.12 no.1
    • /
    • pp.75-84
    • /
    • 1994
  • In this paper we address the issue of how an optimal sample size computation relates the level of precision required for travel demand estimations and transportation planning. We approach the problem by 1) deriving a theoretical solution, 2) developing a computational procedure (algorithm) to implement the theoretical solution, and 3) demonstrating a practical application. Ultimately, we construct a formal scheme of optimal sample size computation for use in travel data collection processe.

  • PDF