• Title/Summary/Keyword: rate of resistance increase

Search Result 687, Processing Time 0.03 seconds

A Study on the Effects of Molding Pressure on the Compressive Strength and Durability of Soil-Cement Mixture (성형압력이 Soil-Cement의 강도 및 내구성에 미치는 영향에 관한 연구)

  • 서원명;고재군
    • Magazine of the Korean Society of Agricultural Engineers
    • /
    • v.20 no.1
    • /
    • pp.4575-4591
    • /
    • 1978
  • In order to investigate the effects of grain size distribution, cement content, and molding pressure on the strength and durability of soil-cement mixtures, a laboratory test of soil cement mixtures was performed at four levels of cement content, five levels of molding pressure, and four levels of normal curing periods. The results are summarized as follows: 1. Optimum moisture contents in loam soil and maximum dry density in sand soil increased with the increase of cement content, but in others, both optimum moisture contents and maximum dry density were changed ununiformly. 2. When the specimens were molded with molding pressure, 50kg/$\textrm{cm}^2$, strength of soil cement mixture with cement content, 2 and 4 per cent, was lower than the strength of soil cement mixture without cement content by more than 40 to 50 per cent. 3. The strength of soil-cement molded with molding pressure, 100kg/$\textrm{cm}^2$, was higher than the strength of soil-cement molded with M.D.D. obtained from standard compaction test more than 40 per cent in sand loam cement and 50 per cent in loamy cement. 4. There was highly significant positive correlation among molding pressure, cement content and unconfined compressive strentgh and so the following multiple regression equations were obtained. Loam: fc=1.9693C+0.197P-0.84 Sandy loam: fc=2.9065C+0.235P-0.77 5. When the specimens were molded with molding pressure, 20 to 100kg/$\textrm{cm}^2$, the regression equation between the 28-day and 7-day strenght was obtained as follows. Loam : q28=1.1050q7+7.59(r=0.9147) Sandy loam : q28=1.3905q7+3.17 (r=0.9801) 6. At the cement contents of above 50 per cent, the weight losses by freeeze-thaw test were negligible. At the cement content of below 8 per cent the weight losses were singnificantly high under low molding pressure and remarkably decreased with the increase of molding pressure up to 80kg/$\textrm{cm}^2$. 7. Resistance to damage from water and to absorption of water were not improved by molding pressure alone, but when the soil was mixtured with cement above 6 per cent, damage seldoms occurred and absorbed less than 5 per cent of water. 8. There was highly significant inverse-corelationship between the compressive strength of soil cement mixtures and their freeze-thaw loss as well as water absorption. By the regression equation methods, the relationships between them were expessed as followed fc=-7.3206Wa+115.6(r=0.9871) log fc=-0.0174L+1.59(r=0.7709) where fc=unconfined compressive stregth after 28-days curing. kg/$\textrm{cm}^2$ Wa=water absorption, % L : freeze-thaw loss rate, %

  • PDF

A Review : On Exercise Performance Induction Gene Factors Change (운동이 유전자 조절물질에 미치는 영향에 관한 고찰)

  • Um, Ki-Mai;Yang, Yoon-Kwon;Kim, Tae-Woo
    • Journal of Korean Physical Therapy Science
    • /
    • v.8 no.1
    • /
    • pp.745-758
    • /
    • 2001
  • The purpose of study to phenomenological examine and the mechanism regarding the gene(DNA, RNA, Protein) and sports to studied, analyzed. and evaluated. This review considers the evidence for genetic effects in several determinants of endurance performance and resistance performance, namely: body measurements and physique, body fat pulmonary functions, cardiac and circulatory functions, muscle characteristics. substrate utilization, maximal aerobic power and other. Moreover, the response to aerobic training of indicators aerobic work metabolism and endurance performance is reviewed, with emphasis on the specificity of the response and the individual differences observed in training ability. This study indicate that improvement of 'Enhancer Action' in RNA genes changed by exercise or sports. Moreover exercise was effect on Central Dogma with DNA makes RNA makes Protein. and think that occurred with exercise influence on skeletal muscle into cell have to Myosin Heavy Chain (MHC) changed was after exercise performance, which accompanied into skeletal muscle that were exercise-induces gene-modulation that is, take gene mutations. This study known that existed hormone(epinephrine)-immune system with interaction. Exercise were altered insulin binding and MAP Kinase signaling increased into immune cells. This review suggested that the high rate of glutamine utilization by cells of the immune system serves to maintain a high intra cellular concentration of the intermediates of biosynthetic pathways such that optimal rates of DNA, RNA and protein synthesis can be maintained. In the absence of glutamine, lymphocytes do not proliferate in vitro: proliferation increase greatly as the glutamine concentration increase. Glutamine is synthesized in skeletal muscle. Skeletal muscle and plasma glutamine levels are lowered by sepsis, injury, bums, surgery and endurance exercise and in the overtrained athlete. The study of result show that production of ET-1 is markedly increased tissue specifically in the heart by exercise without appreciable changes in endothelin-converting enzyme and endothelial receptor expressions, suggest that myocardial ET-1 may participate in modulation of cardiac function during exercise. Conclusionally, this study indicate that improvement of 'Enhancer Action' in RNA genes changed by exercise or sports. Moreover exercise was effect on Central Dogma with DNA makes RNA makes Protein. This study is expected to contribute the area of sports science, medicine, hereafter more effort is required to establish the relation between gene alters and exercise amount.

  • PDF

Sorption Characteristics of Binary Mixture of Corn Starch- Soy Protein Isolates in Plastic film Packaging (Plastic필름 포장에 따른 옥수수 전분과 분리 대두단백질의 이성분 혼합물의 흡습특성)

  • Kim, Duck-Woong;Woo, Sang-Gyu
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.17 no.3
    • /
    • pp.191-197
    • /
    • 1988
  • Sorption properties of corn starch(CS) and Soy protein isolates(SPI) in plastic films packaging were investigates for binary system. The mixture were sealed in plastic films of low density polyethylene(LDPE), oriented polypropylene(OPP) and LDPE/OPP coated film and packaging effect on the changes of moisture sorption during storage at $40^{\circ}C$ were studied. The following results were obtained. The water vapor permeability of material films was $32.6g/m^2/24hrs(below\;g)$ for 0.02mm LDPE film, 14.01g for 0.04mm LDPE film, 7.30g for 0.02mm OPP film, 3.37g for 0.04mm OPP film and 4.869 for 0.02mm LDPE/0.02 mm OPP confine film at $40^{\cire}C$ 90%RH, therefore the OPP film was more effective than LDPE film on the resistance of relative humidity. And the OPP film packaging sealed mixture of food samples was also more elective then LDPE film, having same thickness for increase of water vapor permeability during storage at $40^{\cire}C$. A general increase in sorption rate was found more in SPI than CS in the packaged mixtures.

  • PDF

Microfluidic Immuno-Sensor Chip using Electrical Detection System (전기 검출 시스템을 이용한 Microfluidic Immuno-Sensor Chip)

  • Maeng, Joon-Ho;Lee, Byung-Chul;Cho, Chul-Ho;Ko, Yong-Jun;Ahn, Yoo-Min;Cho, Nahm-Gyoo;Lee, Seoung-Hwan;Hwang, Seung-Yong
    • KSBB Journal
    • /
    • v.21 no.5
    • /
    • pp.325-330
    • /
    • 2006
  • This study presents the characterization of an integrated portable microfluidic electrical detection system for fast and low volume immunoassay using polystyrene microbead, which are used as immobilization surfaces. In our chip, a filtration method using the microbead was adopted for sample immobilization and immunogold silver staining(IGSS) was used to increase the electrical signal. The chip is composed of an inexpensive and biocompatible Polydimethylsiloxane(PDMS) layer and Pyrex glass substrate. Platinum microelectrodes for electric signal detection were fabricated on the substrate and microchannel and pillar-type microfilters were formed in the PDMS layer. With a fabricated chip, we reacted antigen and antibody according to the procedures. Then, silver enhancer was injected to increase the size of nanogold particles tagged with the second antibody. As a result, microbeads were connected to each other and formed an electrical bridge between microelectrodes. Resistance measured through the electrodes showed a difference of two orders of magnitude between specific and nonspecific immuno-reactions. The detection limit was 10 ng/ml. The developed immunoassay chip reduced the total analysis time from 3 hours to 50 min. Fast and low-volume biochemical analysis has been successfully achieved with the developed microfilter and immuno-sensor chip, which is integrated to the microfluidic system.

Improvement of Solar Cell Efficiency according to AC Voltage Variation of Electron Relay Enhancer in High Efficient Solar Cell System using Electron Relay Enhancer (전자전달증대기를 이용한 고효율 태양전지 시스템에서 전자전달증대기 입력 교류 전압 변화에 따른 태양전지 효율 향상에 대한 연구)

  • Kim, Hak Soo;Ryu, Young Kee;Lee, Hyuk;Yun, So Young
    • Journal of the Korean Vacuum Society
    • /
    • v.22 no.3
    • /
    • pp.168-173
    • /
    • 2013
  • In this paper, we would like to introduce Electron Relay Enhancer (ERE), a supplementary device, which improves commercial solar cell efficiency minimizing electron-hole recombination of solar cell. The ERE in this study is mainly composed of two capacitors which are connected to AC power source and bridge diode system which controls electron flow direction. Two capacitors repeat collecting electrons from solar cell and pumping the collected electrons to load resistance or inverter through the bridge diode system. While one positively charged capacitor collect electrons, the other negatively charged one pumps electrons. A positively charged capacitor pulls the more exited electrons from the solar cell, before the exited electrons recombine the holes in solar cell. That is why the ERE system enhances solar cell efficiency. As a result, the measured power increase of the solar cell with the ERE is varied from 5.9 W to 25.6 W in each experimental condition. Maximal increase rate of the solar cell power with ERE is 30.8% of solar cell power without ERE.

Ovarian Features after 2 Weeks, 3 Weeks and 4 Weeks Transdermal Testosterone Gel Treatment and Their Associated Effect on IVF Outcomes in Poor Responders

  • Kim, Chung-Hoon;Ahn, Jun-Woo;Moon, Jei-Won;Kim, Sung-Hoon;Chae, Hee-Dong;Kang, Byung-Moon
    • Development and Reproduction
    • /
    • v.18 no.3
    • /
    • pp.145-152
    • /
    • 2014
  • This study was performed to investigate the effect of of transdermal testosterone gel (TTG) on controlled ovarian stimulation (COS) and IVF outcomes and ovarian morphology according to pretreatment duration in poor responders. A total of 120 women were recruited for this pilot study. They were randomized into control, 2 weeks, 3 weeks or 4 weeks TTG treatment groups. For three TTG treatment groups, 12.5 mg TTG was applied daily for 2 weeks, 3 weeks or 4 weeks in preceding period of study stimulation cycle. After 3 weeks of TTG pretreatment, significant increase of antral follicle count (AFC) and significant decreases of mean follicular diameter (MFD) and resistance index (RI) value of ovarian stromal artery were observed (p=0.026, p<0.001, p<0.01, respectively). The total dose of rhFSH administered for COS significantly decreased after 3 and 4 weeks TTG treatment both compared with control group (p<0.001, p<0.001). The numbers of oocytes retrieved and mature oocytes were significanty higher in 3 and 4 weeks TTG treatment groups than control group (p<0.001, p<0.001 in the number of oocytes retrieved; p<0.001, p<0.001 in the number of mature oocytes). The clinical pregnancy rate and live birth rate were increased only in 4 weeks TTG treatment group compared with control group (p=0.030 and p=0.042, respectively). These data demonstrated that TTG pretreatment for 3 to 4 weeks increases AFC and ovarian stromal blood flow, thereby potentially improving the ovarian response to COS and IVF outcome in poor responders undergoing IVF/ICSI.

Study on inhibition effects on metastasis and recurrence of Traditional Herb Medicine(THM) (한약의 전이재발억제 효과에 관한 연구)

  • Lee, Sang-Seob;Yoo, Hwa-Seung;Cho, Jung-Hyo;Son, Chang-Kyu;Lee, Yeon-Weol;Cho, Chong-Kwan
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
    • /
    • v.9 no.1
    • /
    • pp.75-87
    • /
    • 2003
  • Recently, the occurrence and death rates of cancer have increased rapidly. Metastasis and recurrence is the most important factor of death from cancer. So inhibition of recurrence and metastasis can increase the cure rate of cancer disease. At the basic chinese traditional medicine(TCM), there are a lot of theory related to neoplasm treatment. The metastasis and recurrence of neoplasm was the basis of yudu(餘毒) on remained neoplasm cell and stagnation of blood, thermotoxo, phlegm, asthenia of healthy enerngy and stagnation of vital energy. The principles therapy of neoplasm on metastasis and recurrence was based on knowledge of the method of support the healthy energy and strengthen the body resistance, promote blood circulation to remove blood stasis, clear away heat and toxic materials, dissipate phlegm and disperse the accumulation of evils. But the major clinical features of neoplasm was to be considered in developing a treatment plan include (1) distinguish between clinical and pathologic staging - acute and chronic, (2) classification of pathologic pattern, and (3) distingction of body situation : for examples asthenia - sthenia etc. It was most important to distinguish between supporting the healthy and eliminating the evil factors and to treat differently at the root and the branch cause of a neoplasm. This paper's results indicate that identification and effective use of THM can inhibite netastasis and recurrence and then it will help increasing survival rate. Also as BioTechnology(BT) has developed rapidly nowadays, as genes related to cancer have revealed. So it will give rise to the development of searching the mechanism of herb medicines which have inhibition effects of metastasis and recurrence.

  • PDF

Studies on the Growth and Nutrient Uptaking of Flag Leaf and Chaff of Rice Plant in Cold Injury Location II, Influence of Different Nitrogen and Silicate Application on the Nutrient Uptaking of Chaff in Rice Plant (냉해지대의 수도생육과 임, 불임인각의 양분흡수에 관한 연구 제3보 질소와 규산시용량의 차이가 인각의 양분흡수에 미치는 영향)

  • Kim, Y.J.;Choi, S.I.;Ra, J.S.;Lee, J.H.
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.28 no.1
    • /
    • pp.81-88
    • /
    • 1983
  • This experiment was conducted to study about influenced inorganic element contents of flag leaf and chaff with different nitrogen and silicate application in Jinan (sea level 303m). The recommended rate of fertilizer application above N 15kg/10a was poor for dry production increment in cold in July elevation and was demanded increment of silicate. In the elevation of cold in July high rates of nitrogen application produced more incomplete grain and a reduced cold tolerance. These effects were due to over-content of soluble nitrogen within flag leaf and disturbance of uptaking potassium and silicate. On the other hand, the application of silicate could increase yield by promoting resistance to cold- damage. The application of increasing level of nitrogen resulted in increasing the contents of total nitrogen and phosphate in both sterile and fertile glumes. The contents of potassium and calcium were the highest at the level of nitrogen 10 - 15kg/10a, but magnessium was rather high at low nitrogen levels. It is interesting that at any level of nitrogen, over 6% higher silicate contents were noted in the fertile chaff than in the sterile chaff. Application of increasing level of silicate fertilizer decreased total nitrogen contents, but increased the contents of phosphate, potassium. and silicate in the chaff. Increasing rate of silicate content by increasing silicate addition was remarkably higher in the fertile chaff than in the sterile chaff.

  • PDF

Tribological study on the thermal stability of thick ta-C coating at elevated temperatures

  • Lee, Woo Young;Ryu, Ho Jun;Jang, Young Jun;Kim, Gi Taek;Deng, Xingrui;Umehara, Noritsugu;Kim, Jong Kuk
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2016.02a
    • /
    • pp.144.2-144.2
    • /
    • 2016
  • Diamond-like carbon (DLC) coatings have been widely applied to the mechanical components, cutting tools due to properties of high hardness and wear resistance. Among them, hydrogenated amorphous carbon (a-C:H) coatings are well-known for their low friction properties, stable production of thin and thick film, they were reported to be easily worn away under high temperature. Non-hydrogenated tetrahedral amorphous carbon (ta-C) is an ideal for industrial applicability due to good thermal stability from high $sp^3$-bonding fraction ranging from 70 to 80 %. However, the large compressive stress of ta-C coating limits to apply thick ta-C coating. In this study, the thick ta-C coating was deposited onto Inconel alloy disk by the FCVA technique. The thickness of the ta-C coating was about $3.5{\mu}m$. The tribological behaviors of ta-C coated disks sliding against $Si_3N_4$ balls were examined under elevated temperature divided into 23, 100, 200 and $300^{\circ}C$. The range of temperature was setting up until peel off observed. The experimental results showed that the friction coefficient was decreased from 0.14 to 0.05 with increasing temperature up to $200^{\circ}C$. At $300^{\circ}C$, the friction coefficient was dramatically increased over 5,000 cycles and then delaminated. These phenomenon was summarized two kinds of reasons: (1) Thermal degradation and (2) graphitization of ta-C coating. At first, the reason of thermal degradation was demonstrated by wear rate calculation. The wear rate of ta-C coatings showed an increasing trend with elevated temperature. For investigation of relationship between hardness and graphitization, thick ta-C coatings(2, 3 and $5{\mu}m$) were additionally deposited. As the thickness of ta-C coating was increased, hardness decreased from 58 to 49 GPa, which means that graphitization was accelerated. Therefore, now we are trying to increase $sp^3$ fraction of ta-C coating and control the coating parameters for thermal stability of thick ta-C at high temperatures.

  • PDF

Removal of CO2 in Syngas using Li2ZrO3 (Li2ZrO3를 이용한 합성가스내의 CO2 제거)

  • Park, Joo-Won;Kang, Dong-Hwan;Yoo, Kyung-Seun;Lee, Jae-Goo;Kim, Jae-Ho;Han, Choon
    • Applied Chemistry for Engineering
    • /
    • v.17 no.3
    • /
    • pp.250-254
    • /
    • 2006
  • Reaction of $CO_2$ with $Li_{2}ZrO_{3}$ has been investigated in a TGA and the effects of $H_{2}$ and CO on the removal of $CO_{2}$ using $Li_{2}ZrO_{3}$ were evaluated in a packed bed reactor. The initial rate of $CO_{2}$ removal reaction of $Li_{2}ZrO_{3}$ increased with the increase of gas flow rate up to 100 mL/min and then was maintained, which implied the disappearance of the gas film resistance. The reaction of $CO_{2}$ with $Li_{2}ZrO_{3}$ took place as the first order and the range of optimum temperature was found to be about $500{\sim}600^{\circ}C$. XRD and SEM analysis showed the formation of crystalline $Li_{2}ZrO_{3}$ and porous $Li_{2}ZrO_{3}$/$ZrO_{2}$. The presence of $H_{2}$ did not affect the adsorption of $CO_2$ with $Li_2ZrO_3$. On the other hand, CO inhibited the sorption of $CO_{2}$ into $Li_{2}CO_{3}$(L) on $Li_{2}ZrO_{3}$.