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Literatural Study on the Causes of Infertility in Women (여성(女性) 불임(不姙)의 원인(原因)에 관(關)한 문헌적(文獻的) 고찰(考察))

  • Kim, Eun Seop;Yoo, Dong Yeol
    • Journal of Haehwa Medicine
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    • v.9 no.1
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    • pp.267-285
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    • 2000
  • According to the literatural study on the causes of Infertility in women, the results were as follows. 1. The causes of Infertility in women were arranged scholarly thoery during to Jin-Yuan era (金 元 時代) from Huang-Di-Nei-Jing(黃帝內經), and literatures after Ming-Qing era(明 淸 時代) divided and added one's own thoery since they choose preceding thoery. 2. In the Modern Medicine, the causes of Infertility in women are divided the product obstruction of Oocyte, the union obstruction of sperm and oocyte by abnormality of vagina, cervix, corpus, fallopian tubes, pelvic, and peritoneum, Endocrine factor, Immunologic factor, and Emotion factor. 3. In the Oriental Medicine, the causes of Infertility in women are attached importance to functional side as 'asthenia-cool of uterus'(子宮虛寒), 'deficiency of vital energy and blood'(氣血虛), 'deficiency of yin'(陰虛), 'impairement of seven emotion'(七情傷), 'disease of extra mierdians'(寄經病), and so forth; while on the other in the Modern Medicine, the causes of Infertility in women are attached importance to organic side as abnormality of uterus and ovary. 4. In the successive literatures, 'asthenia-cool of uterus'(子宮虛寒) occupied most frequency in the causes of Infertility in women and in the next obesity(體肥), 'deficiency of vital energy and blood'(氣血虛), menstrual irregularity(月經不調), deficiency of yin'(陰虛), 'impairement of seven emotion'(七情傷), emaciation(體瘦), 'disease of extra mierdians'(寄經病), and so forth occupied much frequency. 5. In the bodily form, obesity(體肥) and emaciation(體瘦) occupied comparatively more frequency.

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Effects of Temperatures and Relative Humidities on the Development of Brown Planthopper, Nilaparvata Zugens (Stal) (온도와 습도가 벼멸구의 생육에 미치는 영향에 관한 연구)

  • Park Chung Gyoo;Hyun Jai Sun
    • Korean journal of applied entomology
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    • v.22 no.4 s.57
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    • pp.262-270
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    • 1983
  • The newly hatched nymphs of brown planthopper(BPH) were reared individually for two generations in test tubes, where young rice seedling was planted on agar solution, at $30^{\circ}C,\;25^{\circ}C\;and\;20^{\circ}C\;with\;95\%,\;75\%,\;65\%\;and\;35\%$ R.H. Effects of $30^{\circ}C$ on the development of BPH when compared with those of $25^{\circ}C$ are followings. Egg period, nymphal period, and adult longevity were shortened. Nymphal mortality was increased and the number of oviposited eggs was decreased. Hatchability was zero per cent because the eggs were either unfertilized or died before finishing the development. At the low temperature of $20^{\circ}C$, in comparision with $25^{\circ}C$, the developmental period of nymphs and eggs was considerably lengthened, and adult longevity was shortened, the number of oviposited eggs was decreased. The nymphal mortality was higher at high relative humidity $(above\;75\%\;RH)$ than that at low relative humidity $(under\;65\%\;RH)$. Under the condition of high relative humidities, the adult longevity was shortened, and the number of oviposited eggs was decreased.

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Experimental Study of the Shock Wave Dynamics in Micro Shock Tube (Micro Shock Tube에서 발생하는 충격파 실험)

  • Park, Jinouk;Kim, Gyuwan;Kim, Heuydong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.17 no.5
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    • pp.54-59
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    • 2013
  • Micro shock tubes are now-a-days used for a variety engineering applications such as in the field of aerospace, combustion technology and drug delivery systems. But the flow characteristics of micro shock tube will be different from that of well established conventional macro shock tube under the influence of very low Reynolds number and high Knudsen number formed due to smaller diameter. In present study, experimental studies were carried out to a closed end (downstream) Micro Shock Tube with two different diameters were investigated to understand the flow characteristics. Pressure values were measured at different locations inside the driver and driven section. The results obtained show that with the increase in diameter the shock propagation velocity increases as well as the effect of reflected shock wave will be more significant under the same diaphragm rupture pressure.

Methodology for real-time adaptation of tunnels support using the observational method

  • Miranda, Tiago;Dias, Daniel;Pinheiro, Marisa;Eclaircy-Caudron, Stephanie
    • Geomechanics and Engineering
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    • v.8 no.2
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    • pp.153-171
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    • 2015
  • The observational method in tunnel engineering allows the evaluation in real time of the actual conditions of the ground and to take measures if its behavior deviates considerably from predictions. However, it lacks a consistent and structured methodology to use the monitoring data to adapt the support system in real time. The definition of limit criteria above which adaptation is required are not defined and complex inverse analysis procedures (Rechea et al. 2008, Levasseur et al. 2010, Zentar et al. 2001, Lecampion et al. 2002, Finno and Calvello 2005, Goh 1999, Cui and Pan 2012, Deng et al. 2010, Mathew and Lehane 2013, Sharifzadeh et al. 2012, 2013) may be needed to consistently analyze the problem. In this paper a methodology for the real time adaptation of the support systems during tunneling is presented. In a first step limit criteria for displacements and stresses are proposed. The methodology uses graphics that are constructed during the project stage based on parametric calculations to assist in the process and when these graphics are not available, since it is not possible to predict every possible scenario, inverse analysis calculations are carried out. The methodology is applied to the "Bois de Peu" tunnel which is composed by two tubes with over 500 m long. High uncertainty levels existed concerning the heterogeneity of the soil and consequently in the geomechanical design parameters. The methodology was applied in four sections and the results focus on two of them. It is shown that the methodology has potential to be applied in real cases contributing for a consistent approach of a real time adaptation of the support system and highlight the importance of the existence of good quality and specific monitoring data to improve the inverse analysis procedure.

Residual bond behavior of high strength concrete-filled square steel tube after elevated temperatures

  • Chen, Zongping;Liu, Xiang;Zhou, Wenxiang
    • Steel and Composite Structures
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    • v.27 no.4
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    • pp.509-523
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    • 2018
  • This paper presents experimental results on the residual bond-slip behavior of high strength concrete-filled square steel tube (HSCFST) after elevated temperatures. Three parameters were considered in this test: (a) temperature (i.e., $20^{\circ}C$, $200^{\circ}C$, $400^{\circ}C$, $600^{\circ}C$, $800^{\circ}C$); (b) concrete strength (i.e., C60, C70, C80); (c) anchorage length (i.e., 250 mm, 400 mm). A total of 17 HSCFST specimens were designed for push-out test after elevated temperatures. The load-slip curves at the loading end and free end were obtained, in addition, the distribution of steel tube strain and the bond stress along the anchorage length were analyzed. Test results show that the shape of load-slip curves at loading ends and free ends are similar. With the temperature constantly increasing, the bond strength of HSCFST increases first and then decreases; furthermore, the bond strength of HSCFCT proportionally increases with the anchoring length growing. Additionally, the higher the temperature is, the smaller and lower the bond damage develops. The energy dissipation capacity enhances with the concrete strength rasing, while, decreases with the temperature growing. What is more, the strain and stress of steel tubes are exponentially distributed, and decrease from the free end to loading end. According to experimental findings, constitutive formula of the bond slip of HSCFST experienced elevated temperatures is proposed, which fills well with test data.

Electrochemical double layer capacitors with PEO and Sri Lankan natural graphite

  • Jayamaha, Bandara;Dissanayake, Malavi A.K.L.;Vignarooban, Kandasamy;Vidanapathirana, Kamal P.;Perera, Kumudu S.
    • Advances in Energy Research
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    • v.5 no.3
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    • pp.219-226
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    • 2017
  • Electrochemical double layer capacitors (EDLCs) have received a tremendous interest due to their suitability for diverse applications. They have been fabricated using different carbon based electrodes including activated carbons, single walled/multi walled carbon nano tubes. But, graphite which is one of the natural resources in Sri Lanka has not been given a considerable attention towards using for EDLCs though it is a famous carbon material. On the other hand, EDLCs are well reported with various liquid electrolytes which are associated with numerous drawbacks. Gel polymer electrolytes (GPE) are well known alternative for liquid electrolytes. In this paper, it is reported about an EDLC fabricated with a nano composite polyethylene oxide based GPE and two Sri Lankan graphite based electrodes. The composition of the GPE was [{(10PEO: $NaClO_4$) molar ratio}: 75wt.% PC] : 5 wt.% $TiO_2$. GPE was prepared using the solvent casting method. Two graphite electrodes were prepared by mixing 85% graphite and 15% polyvinylidenefluoride (PVdF) in acetone and casting n fluorine doped tin oxide glass plates. GPE film was sandwiched in between the two graphite electrodes. A non faradaic charge discharge mechanism was observed from the Cyclic Voltammetry study. GPE was stable in the potential windows from (-0.8 V-0.8 V) to (-1.5 V-1.5 V). By increasing the width of the potential window, single electrode specific capacity increased. Impedance plots confirmed the capacitive behavior at low frequency region. Galvanostatic charge discharge test yielded an average discharge capacity of $0.60Fg^{-1}$.

Comparison of the Friction-Loss Coefficient for the Gap of Two Contact Surfaces and a Crack (접촉한 두 평면과 균열한 틈새에서의 유동마찰계수 비교)

  • Nam, Ho-Yun;Choi, Byoung-Hae;Kim, Jong-Bum;Lee, Young-Bum
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.10
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    • pp.1075-1081
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    • 2011
  • A leak-detection method has been developed by measuring the pressure variation between the inner and outer heattransfer tubes of a double-wall tube steam generator. An experiment was carried out to measure the leak rate in the gap between two surfaces pressed with a hydraulic press in order to simulate the phenomena, and a correlation was determined for the leak rate in a micro gap. However, in the correlation, the gap width and friction coefficient were coupled with the surface roughness, which affects the two parameters. The two parameters were separated using a surface-contact model to develop a correlation for the friction coefficient. The correlation was compared with the existing correlations used for crack analysis. Although the applied ranges of Reynolds numbers were different, the developed correlation for Reynolds numbers of 0.1.0.35 showed similar tendencies to existing correlations used for higher Reynolds numbers.

Design and Performance Evaluation of Dimpled EGR Cooler (딤플형 EGR 냉각기의 설계 및 성능평가)

  • Seo, Young-Ho;Lee, Hyun-Min;Heo, Seong-Chan;Ku, Tae-Wan;Song, Woo-Jin;Kang, Beom-Soo;Kim, Jeong
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.3
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    • pp.291-298
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    • 2010
  • A conventional EGR cooler, which is used in an EGR system of an automobile diesel engine, has a low heat-exchange efficiency. To maximize the heat transfer between the exhaust gas and coolant, dimples are formed on the surface of heat exchange tubes. When designing the dimpled EGR cooler, the net heat transfer areas in the conventional and dimpled tube-type EGR coolers are compared. Structural integrity evaluations are also performed by combining finite element analysis with a homogenization method. Subsequently, the process of manufacturing the dimpled tube, i.e., the formation of dimples, edge bending, center v-notch bending, compression, and plasma welding, is established and carried out. Thus, the dimpled EGR cooler is developed, and its performance is verified.

A Study on the Thermal-Hydraulic Characteristics of Molten Salt in Minichannels of an Intermediate Heat Exchanger for a Very High Temperature Reactor (VHTR) (초고온원자로 중간열교환기 미니챈널에서의 Molten Salt 열수력 특성 연구)

  • Jeong, Hui-Seong;Hwang, In-Seon;Bang, Kwang-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.12
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    • pp.1093-1099
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    • 2010
  • For Very High Temperature Reactors (VHTR), the designs of the Intermediate Heat Transport Loop (IHTL) and the Intermediate Heat Exchanger (IHX) are particularly difficult because of the high-temperature operation (up to $950^{\circ}C$). In this study, Flinak molten salt, a eutectic mixture of LiF, NaF, and KF (46.5:11.5:42.0 mole %) is considered as the heat transporting fluid in the IHTL. To evaluate the flow and heat transfer performance of the Flinak molten salt in small channels with hydraulic diameters in the millimeter range, a double-pipe heat exchanger was constructed using small-diameter tubes for the heat exchange between the Flinak and the gas flow. The experimental data showed that, for laminar Flinak flow, the measured friction factors were close to the 64/Re curve and the Nusselt numbers were generally between 3.66 and 4.36.

Radiation Effects on Pyricularia oryzae Cav. Causing Rice Blast Disease Organism (도열병균의 방사선감수성에 관한 연구)

  • Kwon Shin Han;Oh Jeung Haing;Kim Ho Won
    • Korean journal of applied entomology
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    • v.13 no.4 s.21
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    • pp.245-249
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    • 1974
  • In order to establish a dose limits for subsequent induced mutation research itl Pyricularia oryzae, X-ray sensitivity of the conidia and the vegetative hypae of the fungus, race N-1, was investigated. Conidia of the fungus irradiated with X-rays reduced significantly in spore germination inversely with radiation doses. A severe suppression of conidia germination in about $80\%$ was found at the dose of 120kR, and the rests of the conidia produce very short and lysed germ tubes. A stimulated effect was observed in the elongation of hyphae from the conidia of 10 kR irradiation at initial stage of the growth. The radiosensitivity of hyphae was exremely higher than that of conidia with the increase of radiation doses. It was also recognized that the frequency of X-ray induced mutation in pathogenicity was directly proportional to radiation doses.

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