• Title/Summary/Keyword: Zero

Search Result 9,250, Processing Time 0.041 seconds

Analysis Method for Non-Linear Finite Strain Consolidation for Soft Dredged Soil Deposit - Part II: Analysis Method and Craney Island Case Study (초연약 준설 매립지반의 비선형 유한변형 압밀해석기법 - Part II: 해석기법과 Craney Island 사례분석)

  • Choi, Hang-Seok;Kwak, Tae-Hoon;Lee, Chul-Ho;Lee, Dong-Seop;Stark, T.D.
    • Journal of the Korean Geotechnical Society
    • /
    • v.27 no.11
    • /
    • pp.5-15
    • /
    • 2011
  • This paper presents two analysis methods for characterizing the non-linear finite strain consolidation behavior of highly deformable dredged soil deposits along with the fundamental parameters obtained in the companion paper; that is, the zero effective stress void ratio, the non-linear relationships of void ratio-effective stress and void ratio-hydraulic conductivity. The simplified Morris's analytical solution (2002) and the widely recognized numerical program, PSDDF (primary Consolidation, Secondary Compression, and Desiccation of Dredged Fill) for both single and double drainage conditions are adopted in this paper to verify a series of laboratory experiments for self-weight consolidation of the Incheon clay and Kaolinite. The comparisons show that the analysis methods proposed herein can properly simulate the long-term non-linear finite strain consolidation behavior for dredged soils in the field. In addition, a case study for the artificial Craney Island has been conducted to illustrate the importance of obtaining appropriate non-linear finite strain consolidation parameters and the applicability of PSDDF in promoting dredged soil disposal.

Pharmacokinetics of Paclitaxel in Rabbits with Renal Failure Induced by Folic Acid (신장장애 가토에서 파크리탁셀의 약물동태)

  • Jung, Eun Jung;Gwak, Hye Sun;Choi, Jun Shik;Lee, Jin Hwan;Li, Xiuguo
    • Korean Journal of Clinical Pharmacy
    • /
    • v.12 no.2
    • /
    • pp.91-95
    • /
    • 2002
  • The pharmacokinetics of intravenous paclitaxel (1 mg/kg) were investigated in rabbits with renal failure induced by folic acid. The area under the plasma concentration-time curve from time zero to time infinity (AUC) of paclitaxel was significantly (p<0.05) greater in rabbits with severe renal failure induced by folic acid $(1030\pm382)$ compared to that in rabbits with in moderate renal failure induced by folic acid $(780\pm209\;ng/ml{\cdot}hr)$. The apparent volume of distribution (Vd) $(0.008\pm0.002\;L/kg)$ and the elimination rate constant $(\beta)\;(0.09\pm0.025\;hr^{-1})$ of paclitaxel in rabbits with severe renal failure were significantly (p<0.05) smaller and slower respectively than those of control rabbits $(0.016\pm0.004\;L/kg,\;0.12\pm0.03\;hr^{-1})$, but not significantly different compared with that in rabbits with moderate renal failure $(0.010\pm0.003\;L/kg,\;0.10\pm0.026\;hr^{-1})$. total body clearance (CL) of paclitaxel in rabbits with severe renal failure $(0.97\pm0.183\;L/hr/kg)$ was significantly (p<0.05) slower than that in control rabbits $(1.68\pm0.440\;L/hr/kg)$, but not significantly different compared with that in rabbits with in moderate renal failure $(1.28\pm0.311\;L/hr/kg)$. The terminal half-life ($t_{1/2}$) of paclitaxel in rabbits with severe renal failure $(7.46\pm2.16\;hr)$ was significantly (p<0.05) longer than that in control rabbits $(5.75\pm1.44\;hr)$, but not significantly different compared to that in rabbits with moderate renal failure rabbits $(6.67\pm1.76\;hr)$. The above data could be at least partly decrease in due to paclitaxel excretion in rabbits with renal failure, since $7-15\%$ of interavenous paclitaxel was excreted via kidney as unchanged forms plus its metablites.

  • PDF

Recognition of Efficiency and Effectiveness of the Experiences with Hand Acupuncture (수지침 경험자들의 수지침에 대한 효율성과 효과성 인식정도)

  • Lee, Yeon-Joo;Park, Kyung-Min
    • Research in Community and Public Health Nursing
    • /
    • v.12 no.1
    • /
    • pp.278-287
    • /
    • 2001
  • The purpose of this study is to provide with basic information on application of hand acupuncture as a complementary and alternative therapy by giving some recognition of efficiency and effectiveness of hand acupuncture. And so, answers for questionnaires of 290 respondents were used for this research and collected from June 5 through 13, 1999 from adults twenty and over who were participating in the hand acupuncture training program in Seoul and had some direct experiences with hand acupuncture therapy, whatever they had been treated and/or had treated. To secure reliability of measurement tool. Cronbach'a has been calculated and Factor Analysis was done as Validity Analysis of question classification. Demograprucal characteristics of hand acupuncture experienced people and factors related to hand acupuncture experiences are calculated based on the real number and percentage. The degree of recognition of efficiency and effectiveness of hand acupuncture is made as average and standard deviation, while the degree of recognition of efficiency and effectiveness based on general characteristics come from one-way ANOVA. 1. According to socio-demographical analysis. the questioned could be classified firstly as age (40-49 : 32.5%. 30-39 : 24.9%. 50-59 : 21.9%. 60-69 : 14.7%. 20-29 : 6.0%). secondly gender (male 36.6%. female 63.4%). thirdly occupation (housewife: 43.8%. self-employed: 15.5%. company-employee: 14.8%). fourthly education (high school graduate: 41.9%, college graduate: 37.9%), and lastly monthly-income (1 to 2 million: 51.4%. 2 to 3 million: 20,3%) 2, As for the general aspects related to hand acupuncture. 80,0% of the respondents answered almost zero for the monthly average number of visit to hospital and 15.5% responded 1 to 2 visits, 6,2% of the respondents is complaining of a disorder of digestive system. 19,0% circulatory disease, 10.7% bad nervous system. By utilizing hand acupuncture, 84% of the questioned have following experiences in curing diseases: digestive system 47.3%, circulatory system 9.3%, nervous system 8.3%, 54,1% are curing 1 to 2 and 10.3% 3 to 4 patients on a daily basis with hand acupuncture. Research on the demerits of giving medical treatment with hand acupuncture shows 23,8% are feeling economic burden. 16.6% difficulty of learning and 16.2% weak theoretical backgrounds. 3. Among the efficiency recognition, possibility of general application is average 4,29 and simple treatment is 4,19. economic merits 4.36. possibility of establishment with supplementary and alternative medicine 4.17, medical effectiveness 4.09. 4, As a result of demographical analysis on the efficiency and effectiveness of hand acupuncture therapy, it appears that the recognition of efficiency based on occupation and the recognition of effectiveness based on monthly income are most significant to be noticed. In an orderly fashion. government-employee, self-employed, company-employee. and then housewife have perceived hand acupuncture very efficiently, And those who recognize hand acupuncture to be most effective are people earn 1 million to 2 million won a month, 5. The efficiency(p = .003) and effectiveness (p= .049) of hand acupuncture therapy by number of visit to hospital were statiscally significant, and effectiveness of hand acupuncture therapy by disease exist was statiscally significant (p= .033).

  • PDF

Egg Retrieval as a Source of Nests with Supernormal and Mixed Egg Clutch in Little Terns Sterna albifrons (쇠제비갈매기 Sterna albifrons의 과산란 및 이종 알 혼합 둥지 생성 원인으로서 알 회수 행동)

  • Kim, Jeong-Hoon;Nam Hyung-Kyu;Fulton Graham R.;Yoo Jeong-Chil
    • Journal of Ecology and Environment
    • /
    • v.29 no.6
    • /
    • pp.545-550
    • /
    • 2006
  • Ten supernormal clutches of little terns Sterna albifrons and seven clutches having mixed eggs by little terns and kentish plovers Charadrius alexandrinus were recorded during the breeding seasons of 2003$\sim$2005 at Ganwol lake, Hongsung-gun, Chungcheongnam-do, Korea. The frequency of egg retrieval by Little Terns was higher after the second egg laying regardless of the clutch size and incubation stage. The frequency of egg retrieval was high at all incubation stage. When experimental eggs were placed within 15 cm from the nests, the percentage of egg retrieval was highest (almost 100%). However the percentage dropped rapidly over 35$\sim$55 cm range and finally to zero at 60 cm distance. Little terns retrieved all kinds of eggs set near their nests regardless of its kind or size. This study suggests that egg retrieval by little terns may be a source of the nest with supernormal and mixed egg clutch observed in this species.

Development of block-type sidewalk pavement system using snow-melting system (융설시스템을 이용한 조립식 보도포장 기술 개발)

  • Park, Kyungmo;Lee, Jeonguk;Kim, Changduk
    • Korean Journal of Construction Engineering and Management
    • /
    • v.16 no.6
    • /
    • pp.136-143
    • /
    • 2015
  • Snow-melting system has been applied not only to roads for car traffic but also to pavement for the pedestrians safety reason in some of the developed countries such as USA and Canada based on countermeasures against Natural Disasters Act revised in 2000. Even though this system was introduced in korea in 2006 and has been partly applied to car traffic roads, there is few places that the system has been applied. Therefore, in this research a snow-melting system with a block-type to cover a pavement that efficiently transfers heat form heat rays to the top of a pavement and protects the heat rays. A quality check showed that compression and bending strength was improved approximately 5 times stronger and 7 to 10 times more absorption rate than the KS(Korea Industrial Standard) requirement. Moreover, only 10 minute was required to increase temperature above zero with a block-type snow-melting system whereas approximately 180 minute was spent with the existing system. This research is expected to contribute to environmental issues and reduce accidents on a slippery road.

Characteristics of Coal Methanation in a Hydrogasifier (수소가스화기에서 석탄의 메탄화 반응 특성)

  • Lee, S.H.;Yoon, S.J.;Choi, Y.C.;Kim, J.H.;Lee, J.G .
    • Korean Chemical Engineering Research
    • /
    • v.44 no.6
    • /
    • pp.631-635
    • /
    • 2006
  • To investigate the characteristics of substitute natural gas (SNG) production from direct coal methanation, the continuous lab-scale entrained flow hydrogasifier (I.D. : 0.025 m, Height : 1.0 m) was used in this experiment. The hydrogasification system consisted of high pressure gas handling system, high pressure coal feeder, entrained flow hydrogasifier, and unreacted char separator. The experiment was performed at the various conditions of reaction temperature ($600{\sim}800^{\circ}C$), $H_2$/coal ratio (0.2~0.4), and coal feed rate (0.8~2.5 g/min). Although it was shown that carbon conversion was different trends with coals from the methanation results for 6 sample coals, the carbon conversion increased with increasing reaction temperature. And it increased with increasing H2/coal ratio, whereas the concentration of CH4 decreased. Also. the carbon conversion increased with the carbon content of coal sample and had a maximum value at volatile matter content of 35 wt%.

Design of Format Conversion Filters for MPEG-4 (MPEG-4를 위한 포맷 변환 필터의 설계)

  • Jo, Nam Ik;Kim, Gi Cheol;Yu, Ha Yeong
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.22 no.4
    • /
    • pp.637-637
    • /
    • 1997
  • In this paper, format conversion filters are proposed, which have advantages in hardware implementation compared to the ones proposed in MPEG-4 Video Verification Model. since each coefficients of the proposed filters is constrained to have less than two non-zero digits in minimal signed digit representation, multiplication of input and the coefficient can be implemented by a single adder. As a result, the proposed filters have advantages in hardware complexity and speed, compared to the filters which are usually implemented by integer multiplier or carry save adders. Six kinds of filters are proposed in MPEG-4 Video Verification Model for size conversion of 2:1, 4:1, 5:3 and 5:6. We design 5 filters for the same purpose and compare the performance. The remaining one is very simple to implement. For comparing the filtering performance, we first compare the results of sine wave frequency conversion as an indirect but meaningful comparison. Second. We compute the PSNR of the images obtained from the proposed filters and the ones proposed by MPEG, with reference to the images obtained by using double precision arithmetic and high order filter. The results show that the performance of the proposed filters is almost the same as that of the filters proposed by MPEG. In conclusion, the peroformance of the proposed filters is comparable to that of the ones in MPEG-4, while requiring lower hardware complexity and providing high operating speed.

Development of the Calorimeter to Measure Heat Rate Generated from Battery for EV & HEV (전기자동차용 축전지의 발열량 측정을 위한 열용량계 개발)

  • Yang Cheol-Nam;Park Seong-Yong
    • Journal of the Korean Electrochemical Society
    • /
    • v.2 no.4
    • /
    • pp.218-220
    • /
    • 1999
  • The performance of the Electric Vehicle and Hybrid Electric Vehicle depends on that of the battery pack composed of series connected batteries. And thermal property is one of the main factors which decide the performance of the battery pack. So heat generation rate from the battery under the various driving mode must be measured as precise as possible because thermal characteristics of the battery affect the driving performance and battery pack's life cycle. Besides, to design and develop the battery thermal management system for the EV and HEV, the measurements of the thermal properties of the batteries are needed. However, the established calorimeter is not adequate to test an EV's battery because its cavity is too small to accommodate the EV's battery. Therefore we developed the calorimeter to test the thermal property of the EV's battery. Its cavity size is 120mm long, 75mm wide and 200mm high. The calorimeter is calibrated by the dummy cell which generates the heat rate from zero to 200W. The measuring accuracy of the calorimeter is within $2\%$ and its voltage stability is 2.5mV in the constant temperature bath.

Photoeletrochemical Properties of α-Fe2O3 Film Deposited on ITO Prepared by Cathodic Electrodeposition (음극전착법을 이용한 α-Fe2O3 막의 광전기화학적특성)

  • 이은호;주오심;정광덕;최승철
    • Journal of the Korean Ceramic Society
    • /
    • v.40 no.9
    • /
    • pp.842-848
    • /
    • 2003
  • Semiconducting $\alpha$-Fe$_2$O$_3$ film was prepared by the cathodic electrodeposition method on Indium Tin Oxide (ITO) substrate for photoelectrochemical cell application. After heat treatment at 50$0^{\circ}C$, the phase was changed from Fe to $\alpha$-Fe$_2$O$_3$. The phase, morphology, absorbance, and photocurrent density (A/$\textrm{cm}^2$) of the film depended on the preparation conditions: deposition time, applied voltage, and the duration of heat treatment. The $\alpha$-Fe$_2$O$_3$ film was characterized by X-Ray Diffractometer (XRD), Scanning Electron Microscope (SEM), and UV -Visible Spectrophotometer. The stability of the $\alpha$-Fe$_2$O$_3$ film in aqueous solution was tested at zero bias potential under the white-light source of 100 mW/$\textrm{cm}^2$. The apparent grain size of the films formed at -2.0 V was larger than that grown at -2.5 V. The $\alpha$-Fe$_2$O$_3$ film deposited at -2.0 V for 180 s and heat-treated at 50$0^{\circ}C$ for 1 h showed the predominant photocurrent of 834$\mu$A/$\textrm{cm}^2$.

Wall Shear Stress Distribution in the Abdominal Aortic Bifurcation : Influence of wall Motion, Impedance Phase Angle, and non-Newtonian fluid (복부대동맥 분기관에서의 벽면전단응력 분포 벽면운동과 임피던스 페이즈 앵글과 비뉴턴유체의 영향)

  • Choi J.H.;Kim C.J.;Lee C.S.
    • Journal of Biomedical Engineering Research
    • /
    • v.21 no.3 s.61
    • /
    • pp.261-271
    • /
    • 2000
  • The present study investigated flow dynamics of a two-dimensional abdominal aortic bifurcation model under sinusoidal flow conditions considering wall motion. impedance phase angle(time delay between pressure and flow waveforms), and non-Newtonian fluid using computational fluid dynamics. The wall shear stress showed large variations in the bifurcated region and the wall motion reduced amplitude of wall shear stress significantly. As the impedance phase angle was changed to more negative values, the mean wall shear stress (time-averaged) decreased while the amplitude (oscillatory) of wall shear stress increased. At the curvature site on the outer wall where the mean wall shear stress approached zero. influence of the phase angle was relatively large. The mean wall shear stress decreased by $50\%$ in the $-90^{\circ}$ phase angle (flow wave advanced pressure wave by a quarter period) compared to the $0^{\circ}$ phase angle while the amplitude of wall shear stress increased by $15\%$. Therefore, hypertensive patients who tend to have large negative phase angles become more vulnerable to atherosclerosis according to the low and oscillatory shear stress theory because of the reduced mean and the increased oscillatory wall shear stresses. Non-Newtonian characteristics of fluid substantially increased the mean wall shear stress resulting in a less vulnerable state to atherosclerosis.

  • PDF