• Title/Summary/Keyword: D/d ratio

Search Result 9,650, Processing Time 0.04 seconds

Relational Analysis between Digit Length Ratio and Physical Fitness (손가락 비율과 체력과의 관계 분석)

  • Choi, Kyeongho;You, Kangwon;You, Kangsoo
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2012.05a
    • /
    • pp.409-410
    • /
    • 2012
  • 낮은 악력과 높은 악력으로 2등분 했을 때, 손가락 비율(2D:4D)에 대해 낮은 악력을 가진 남자가 높은 악력을 가진 남자보다 더 높은 2D:4D 비율을 가지고 있다. 이와 같은 이론을 토대로, 국내 대학생 중 축구선수를 대상으로 손가락 비율(2D:4D)과 체력과의 상관관계를 분석해보고자 한다.

  • PDF

Clinical Analysis of Postoperative Acute Renal Failure in the Patients undergoing Cardiovascular Operation with CPB (개심술 후 발생한 급성 신부전의 임상적 고찰)

  • 편승환;노재욱;방정희;조광조;성시찬;우종수
    • Journal of Chest Surgery
    • /
    • v.31 no.5
    • /
    • pp.494-501
    • /
    • 1998
  • From May 1, 1993 to May 31 1995, the authers studied retrospectively 211 patients who underwent cardiovascular operation with cardiopulmonary bypass(CPB). Because we were interested in new development of ARF(prevalence, mortality rate, and main risk factors), we performed a multivariate statistical analysis about data of patients with preoperative serum creatinine values of less than 1.5 mg/dL. Normal renal function before operation(serum creatinine level less than 1.5 mg/dL) was registered in 198(74%) patients. Of these, 27(14%) patients showed postoperative renal complication, including 20(10%) patients classified as renal dysfunction(serum creatinine level between 1.5 and 2.5 mg/dL) and 7(4%) patients as acute renal failure(serum creatinine level higher than 2.5 mg/dL). The mortality rate was 5.8% in normal patients, 5% in patients with renal dysfunction, and 43% when acute renal failure developed(p=0.036). Indeed, the renal impairment proved to be an independent predictor of mortality(odd ratio 2.52∼11.25), along with cardiovascular(odd ratio 4.20) and respiratory(odd ratio 2.18) complications. Multivariate analysis identified the following variables as independent risk factors for postoperative renal impairment : advanced age(odd ratio 1), need for emergency operation(odd ratio 3.78), low-output syndrome(odd ratio 3.66), respiratory complication(odd ratio 1.30), need for deep hypothermic circulatory arrest(odd ratio 1.4). The 13 patients(7%) with preoperative renal failure showed a significantly higher morbidity and mortality rate than those without renal complications before operation. We concluded that the likelihood of severe renal complications is resonably low in the patients undergoing cardiac operation without preexisting renal dysfunction, but associated mortality remains high. A prominant role of hemodynamic factor in the development of postoperative acute renal failure must be recognized during preoperative, intraoperative, and postoperative periods.

  • PDF

The Evaluations of Phoria and AC/A Ratio by Watching 3D TV at Near (3D TV 근거리 시청에 따른 사위도와 조절성폭주비 평가)

  • Son, Jeong-Sik;Kim, Dong-Su;Kim, Jung-Ho;Kim, Jae-Do;Hamacher, Alaric;Yu, Dong-Sik
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.20 no.3
    • /
    • pp.319-324
    • /
    • 2015
  • Purpose: This study was designed to evaluate the changes of phoria and calculated AC/A ratio, and their recovery time points by watching 3D television (3D TV). Methods: 50 subjects (male 30, female 20) of 20s to 40s ages who can watch 3D, were measured phoria using a Howell phoria card at 3 m for distance and 40 cm for near. The phoria was evaluated before watching 3D TV and every 10 minutes from starting of watching 3D TV for 30 minutes, and every 5 minutes after finishing of watching 3D TV for 30 minutes again. Results: For the distance phoria during and after watching 3D TV, it was increased to more exophoria $-0.98{\pm}1.37{\Delta}$ (prism diopters) after 10 minutes from starting of 3D TV watching (p=0.063) and increased to more exophoria $-1.00{\pm}1.28{\Delta}$ after 30 minutes (p=0.024), and started to decrease after finishing of watching 3D TV and recovered to the level of before 3D TV watching ($-0.78{\pm}1.11{\Delta}$) after 20 minutes (p=0.32) with comparing to phoria of before watching 3D TV ($-0.80{\pm}1.12{\Delta}$). For the near phoria, it was also increased to more exophoria $-5.71{\pm}4.45{\Delta}$ after 10 minutes from starting of watching 3D TV (p=0.000) and $-6.58{\pm}4.36{\Delta}$ after 30 minutes (p=0.000), and started to decrease after finishing of watching 3D TV and recovered to the level of before watching 3D TV after 20 minutes ($-4.34{\pm}3.67{\Delta}$) (p=0.32) with comparing to the phoria of before watching 3D TV ($-4.36{\pm}3.66{\Delta}$). AC/A ratio was decreased from $4.92{\pm}1.17{\Delta}/D$ for before 3D TV watching to $4.11{\pm}1.50{\Delta}/D$ for after 30 minutes from starting of watching 3D TV (p=0.000), and increased after the end of watching 3D TV and recovered to the level of before 3D TV watching ($4.93{\pm}1.18{\Delta}/D$) after 25 minutes (p=0.598). Conclusions: During watching 3D TV at near, it showed a tendency of convergence insufficiency by decrease of calculated AC/A ratio as result that exophoria at near was higher increased than exophoria at distance. However, the increased exophoria at both near and distance was recovered to the level of base line after 25 minutes from the end of watching 3D TV. Through this study, it seems to need rational proposals of advice for watching 3D TV.

A Study on Calculation of Protection Ratio for Frequency Coordination in Microwave Relay System Networks (M/W 중계 시스템 망의 주파수 조정을 위한 보호비 계산에 대한 연구)

  • Suh, Kyoung-Whoan;Lee, Joo-Hwan
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
    • /
    • 2005.11a
    • /
    • pp.125-130
    • /
    • 2005
  • This paper suggests an efficient method of protection ratio calculation and shows some calculated results applicable to frequency coordination in microwave relay system networks, and the net filter discrimination (NFD) associated with Tx spectrum mask and overall Rx filter characteristics has been examined to obtain the adjacent channel protection ratio. The protection ratio comprises several factors such as C/N of modulation scheme, noise-to-interference ratio, multiple interference allowance, fade margins of multi-path and rain attenuation, and NFD. According to computed results for 6.7 GHz, 64-QAM, and 60 km at BER $10^{-6}$, fade margin and co-channel protection ratio are 41.1 and 75.2 dB, respectively, In addition, NFD for channel bandwidth of 40 MHz reveals 28.9 dB at the first adjacent channel, which results in adjacent channel protection ratio of 46.3 dB. The proposed method provides some merits of an easy calculation, systematic extension, and applying the same concept to frequency coordination in millimeter wave relay system networks.

  • PDF

1D Computer Simulation of Diesel Engine Intake Port Swirl Ratios Considering the Fuel Injection Timing Range (디젤 엔진 연료 분사 타이밍 구간에서의 흡기 포트 스월비 1D 컴퓨터 시뮬레이션)

  • Oh, Dae San;Lee, Choong Hoon
    • Journal of ILASS-Korea
    • /
    • v.26 no.2
    • /
    • pp.81-87
    • /
    • 2021
  • This study was performed to calculate the swirl ratio of a diesel engine intake port by a 1D computer simulation under actual engine operating conditions. The swirl ratio of the intake port was simulated according to the change of the engine speed during the operation of the motoring without fuel injection. The swirl ratio of the intake port was simulated according to changes in the crank angle during the four-cycle operation of intake, compression, expansion and exhaust. The swirl ratio represented by the three regions of the piston, center and squish was simulated. Among the three regions, the piston-region swirl ratio is important for effective air-fuel mixing in the engine cylinder. In particular, it was confirmed during the simulation that the piston swirl ratio before and after the compression top dead center (TDC) point when fuel is injected in the DI diesel engine can have a significant effect on the mixing of air and fuel. It was desirable to set the average piston swirl ratio over a crank angle section before and after compression TDC as the representative swirl ratio of the cylinder head intake port according to the change of the engine speed.

Determining of the Effect of Lysine:calorie Ratio on Growth Performance and Blood Urea Nitrogen of Growing Barrows and Gilts in Hot Season and Cool Season in a Commercial Environment

  • Zhang, Z.F.;Kim, I.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.26 no.3
    • /
    • pp.401-407
    • /
    • 2013
  • Two experiments were conducted to determine an optimum Lys:calorie ratio (g of total dietary Lys/Mcal of DE) for growing barrows and gilts in cool and hot seasons in a commercial environment. In Exp. 1, 96 barrows and 96 gilts were randomly allocated in 1 of 4 dietary treatments (2.7, 3.0, 3.3, 3.6 g of Lys/Mcal of DE). Each treatment had 12 replicate pens with 4 pigs per pen. The experiment lasted for 34 d in the cool season (March 12th to April 15th). Diets were based on corn-wheat-soybean meal. Lys:calorie ratio were attained by adjusting the amount of corn and soybean and supplementation of crystalline Lys. Total Lys intake and available Lys intake were increased (p<.05) as dietary Lys:calorie ratio increased. The BUN concentration on d 34 for barrows, and BUN change for barrows and gilts linearly increased (p<0.05) in response to increasing dietary Lys:calorie ratio. For gilts, back fat was decreased and then increased (Quadratically, p<0.05) as increasing dietary lys:calorie ratio. Exp. 2 had a similar design as Exp. 1 with the exception that Exp. 2 was conducted in hot season (June 30th to September 11th) for 42 d. Diet of Exp. 2 was the same as Exp. 1. Total Lys intake and available Lys intake increased (p<0.05) as dietary Lys:calorie increased. On d 42, the BUN concentration increased (p<0.05) in response to the increasing dietary Lys:calorie ratio. In conclusion, dietary Lys:calorie ratio of 2.7 g of Lys/Mcal of DE could satisfy the requirement of 25 to 50 kg growing pigs. Increasing dietary Lys:calorie ratio could increase BUN concentration in growing pigs.

A Study on Fatigue Crack Propagation Behavior with Pure-Ti Plate (순수 티타늄 판재의 피로균열 전파거동에 관한 연구)

  • 오세욱;김태형;김득진;임만배
    • Journal of Ocean Engineering and Technology
    • /
    • v.9 no.1
    • /
    • pp.92-100
    • /
    • 1995
  • The effect of different anisotropy and stress ratio on fatigue crack propagation behavior was investigated under various stress ratio(R=-0.4, -0.2, 0.2, 0.2, 0.4) using pure titanium sheet used in aerospace, chemical and food industry. The rack closure behavior under constant load amplitude fatigue crack propagation test was examined. Fatigue crack propagation rate da/dN was estimated in terms of effective stress intensity factor range, $\Delta$K$_{eff}$, regardless of various stress ratio but was influenced by anisotropy. Also, it was found that the effect of anisotropy was considerably decreased but still not negligible when he da/dN was evaluated by a conventional parameter, $\Delta$$K_{eff}$/E and when the modified da/dN.$\sqrt{\varepsilon}_f$ was evaluated by $\Delta$$K_{eff}$/E. On the other hand, da/dN could be evaluated uniquely by effective new parameter, $\Delta$K$_{eff}$/$sigma_{ys}$, regardless of anisotropy, as int he following equation da/dN=C''[\frac{{\Delta}K_{eff}}{{\sigma}_{ys}}]^{n''}. And effective stress intensity factor range ratio, U was estimated by the following equation with respect to the ratio of reversed plastic zone size, $\Delta r_{p}$ to monotonic plastic zone size, $r_p$ regardless of stress ratio and anisotropy. U=-4.45$(\Delta r_{p}/r_{p})^{2}$+4.1$(\Delta r_{p}/r_{p})$+0.245_{p})$+0.245

  • PDF

Unequal Power Divider based on Adjustment Electrical Length of Uniform Transmission Line (단일 전송선로의 전기적 길이 조정을 이용한 비대칭 분배기)

  • Kwon, Sang-Keun;Kim, Young
    • Journal of Advanced Navigation Technology
    • /
    • v.22 no.6
    • /
    • pp.642-647
    • /
    • 2018
  • In this paper, an unequal power divider based on adjusting electrical length of uniform transmission line is presented. This divider consists of three uniform transmission lines and one isolation resistor and have the different port impedances of input and output. The feature of proposed divider can changed the power dividing ratio to adjust only electrical length of uniform transmission lines. To verify the feasibility of proposed power divider, two divider circuits are designed, one is 1:2 power dividing ratio divider with $60{\Omega}$ uniform transmission line and $40{\Omega}$ input port impedances and $45{\Omega}$ output port impedances, the performance data were measured the insertion losses of 1.7 dB/ 5.0 dB, return losses of more than -30 dB and isolation of more than -35 dB. The other is 1:4 power dividing ratio divider with $40{\Omega}$ uniform transmission line and $50{\Omega}$ input port impedances and $75{\Omega}$ output port impedances, the performance data were measured the insertion losses of 1.3 dB/ 6.8 dB, return losses of more than -12 dB and isolation of more than -19 dB. The measured performance data agreed well with the simulated results.

An efficient pipelined architecture for 3D graphics accelerator (3차원 그래픽 가속기의 효율적인 파이프라인 설계)

  • 우현재;정종철;이문기
    • Proceedings of the IEEK Conference
    • /
    • 2002.06b
    • /
    • pp.357-360
    • /
    • 2002
  • This paper is proposed about an efficient pipelined architecture for 3D graphics accelerator to reduce Cache miss ratio. Because cache miss takes a considerable time, about 20∼30 cycle, we reduce cache miss ratio to use pre-fetch. As a result of simulation, we figure out that the miss ratio of cache depends on the size of tile, cache memory and auxiliary cache memory. We can save 6.6% cache miss ratio maximumly.

  • PDF