• Title/Summary/Keyword: same distance effect

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The Effects of Substituent, Pressure and Temperature on the Dissociation Constants of Organic Acids (VII). Dissociation Constants of Some ${\omega}$-Amino Acid in Aqueous Solution (유기산의 해리평형에 미치는 치환기 효과와 그의 온도 및 압력의 영향 (제 7 보). 수용액중에서 몇가지 ${\omega}$-아미노산의 해리)

  • Jung Ui Hwang;Young Woo Kwak;Jae Won Jung
    • Journal of the Korean Chemical Society
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    • v.33 no.4
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    • pp.343-349
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    • 1989
  • The dissociation constants of ${\beta}$-alanine and ${\gamma}$-aminobutyric acid were measured in the temperature range from 20 to $40^{\circ}C$ and pressure up to 2,500 bar by conductometric method. The both dissociation constants of respective amino acid increase with temperature increase but pressure effect is not same as the temperature. The $K_1$ increases as pressure increases but $K_2$ decreases. The properties of these amino acids were discussed in terms of the thermodynamic properties of the dissociation reaction. A relationship between the dissociation constants and the distance between substituted groups of amino acid was discussed. The substituted effects of the reaction were deduced from Hammett reaction and substituted constants which were calculated from the measured dissociation constants.

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Vibration Prediction and Charge Estimation in Hard Rock Blasting Site (경암층 발파현장에서 진동예측 및 장약량산정)

  • Park, Yeon-Soo;Park, Sun-Joon;Choi, Sun-Min;Mun, Soo-Bong;Mun, Byeong-Ok;Jeong, Gyung-Yul;Jeong, Tae-Hyeong;Hwang, Seung-Ill;Kim, Min-Jung;Park, Sang-Chul;Kim, Jung-Ju;Lee, Byeong-Geun
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.3
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    • pp.313-319
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    • 2009
  • The blasting has a lot of economic efficiency and speediness but it can damage to a neighbor structure, a domestic animal and a cultured fish due to the blasting vibration, then the public grievance is increased. Therefore, we need to manage the blasting vibration efficiently. The prediction of the correct vibration velocity is not easy because there are lots of different kinds of the scale of blasting vibration and it has a number of a variable effect. So we figure the optimum line through the least-squares regression by using the vibration data measured in hard rock blasting and compared with the design vibration prediction equation. As a result, we confirm that the vibration estimated in this paper is bigger than the design vibration prediction equation in the same charge and distance. If there is a Gaussian normal distribution data on the left-right side of the least squares regression, then we can estimate the vibration prediction equation on reliability 50%(${\beta}=0$), 90%(${\beta}=1.28$), 95%(${\beta}=1.64$). 99.9%(${\beta}=3.09$). As a result, it appears to be suitable that the reliability is 99% at the transverse component, the reliability 95% is at the vertical component, the reliability 90% is at the longitudinal component and the reliability is 95% at the peak vector sum component.

A Study on Rural Planning Technique and Guidance (농촌개발계획 수립 기법 및 지침 작성 연구 - 김제시 대산마을(현황분석 및 기본구상)을 중심으로 -)

  • Cheong, Ji-Woong;Chung, Ha-Woo;Choi, Soo-Myung;Ahn, Tong-Mahn;Lee, Seong-Woo;Choi, Jin-Yong;Hwang, Han-Cheol;Han, Kyung-Soo
    • Journal of Korean Society of Rural Planning
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    • v.6 no.1 s.11
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    • pp.3-9
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    • 2000
  • Rural area is not only majority area of national territories but also conservative area of traditions. But, rural area is, compare to the urban area, keep at a distance from the progression of industrialization and construction of infrastructures, and depopulation by push/pull effect of industrialization caused aged residents of the rural area. vacated space of the rural region, and ruined the rural amenity. And the other side, investment for the agriculture and rural area was focused to development of water and land reclamation for improvement of rice cultivation since late of 1960. As same steps, the rural settlement regional planning project was implemented with nation wide scale ever since the 1990. But, there was no guidance and technique firmly settle down for the rural planning. The rural planning that have rationality and reasonability must be set by systematical approach of planning hierarchies and interdisciplinary of multiple area of research. Hence, the guidance compilation was proposed and implemented for the rural planner and engineers, although timely late.

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Measuring the Earth's Size Using the Sun's Altitude and The Responses

  • Chae, Dong-Hyun
    • Journal of the Korean Society of Earth Science Education
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    • v.5 no.1
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    • pp.88-94
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    • 2012
  • This study was created to resolve the problems embedded in the formal measuring experiments to determine the earth's size in the current curriculum, to develop an updated measuring experiment to determine the earth's size and to establish its effect. For this study, pre-service elementary teachers, who had attempted the experiment of measuring the size of the earth when they were in middle school, performed the experiments in the existing national curriculum, and their responses, collected through in-depth interviews, were examined. To begin with, the pre-service elementary teachers conducted the experiment of measuring the earth size and they recorded the problems while performing it. At the end, an in-depth interview was administered. Based on the problems, an updated measuring experiment to determine the earth's size was suggested to be applied to the same contents and be analyzed through the in-depth interviews. Common themes which were mutually categorized and analyzed by the two researchers were obtained based on the records produced while conducting the experiment and the in-depth interview data. The teachers mentioned that the experiments for measuring the size of the earth in the current curriculum gave rise to difficulties in measuring precisely the angles between the string and the post. Also, there has been a scientific contradiction that solar altitudes were increased in a high latitude region, instead of decreased. For this reason, an alternative method has been developed to measure the earth's size using the distance and the solar altitude difference of two places. The teachers all agreed that by using the updated measuring experiment, they can acquire more precise measurements and it is easier, faster and consequently more effective than the existing methods. Through the results of this study, I suggest that the newly developed experiment by the researchers can overhaul the problems of the current experiments and it can be an effective alternative to the current experiment.

Performance Analysis on the Impact of Mutual Interference and the Interference Suppression Method for CBTC System in the Presence of WPAN System (CBTC시스템과 WPAN시스템의 상호간섭영향 및 간섭신호 억제방안에 대한 성능분석)

  • Kim, Seong Cheol
    • Journal of the Korean Society for Railway
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    • v.15 no.5
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    • pp.454-458
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    • 2012
  • The CBTC(Communication based Train Control) and WPAN(Wireless Personal Area Network) systems employed on 2.4GHz ISM band wireless networks provide complementary service within the same environment. Coexistence between the networks will be impaired if the mutual packets are uncertainty associated the timing or gaussian distance. This paper analyzes the impact of the mutual interference and proposed method to minimize the effect of the WPAN system signals on CBTC system. The performance analysis is illustrated by examining the symbol error rate versus signal to noise interference ratio in terms of carrier frequency offset. The method contributes to reduce the symbol error rate drastically. However it can't be a fundamental solution for the impact on the interference problem. It may be needed for railway only frequency after checking the problems of the current railway frequency.

Temporal Variations in Isotope Ratios and Concentrations of Nitrate-nitrogen in Groundwater as Affected by Chemical Fertilizer and Livestock Manure

  • Yoo, Sun-Ho;Choi, Woo-Jung;Han, Gwang Hyun;Park, Jung-Geun;Lee, Sang-Mo;Jin, Sheng-ai
    • Journal of Applied Biological Chemistry
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    • v.42 no.4
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    • pp.186-190
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    • 1999
  • Isotope ratio ($^{15}N/^{14}N$) and nitrate-nitrogen concentration in groundwater were measured to investigate the effect of chemical fertilizer and livestock manure on temporal variations in nitrate-nitrogen concentration and to estimate the contribution of fertilizer and manure to groundwater contamination by nitrate. Four study wells from a rural area in Kyonggi province were selected. One well was located on an upper site from a livestock feedlot, and the others were situated at lower sites from the feedlot. The ${\delta}^{15}N$ values were analyzed by a stable isotope ratio mass spectrometer (Micromass, VG Optima IRMS). Reproducibility of the method and precision of the mass spectrometer were below 1.0 and 0.1‰, respectively Even though study wells were located at the same area, nitrate-nitrogen concentrations and ${\delta}^{15}N$ values differed and fluctuated during the sampling period. The ${\delta}^{15}N$ values of well located at upper site from the feedlot were extremely variable (-1.48~20.80‰). The ranges of ${\delta}^{15}N$ value of three wells situated at lower sites from the feedlot were 11.83~20.73 (ave. 16.11), 8.90~11.73 (ave.11.01), and 5.29~12.73‰ (ave. 8.21‰) with increasing distance from the feedlot. The average values of contribution proportion of nitrogen derived from livestock manure to nitrate-nitrogen in groundwater were 79% for the well closet to the feedlot, 44% for the well most distant from the feedlot, and 56% for the well in between the two wells.

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A Fast Encoding Algorithm for Image Vector Quantization Based on Prior Test of Multiple Features (복수 특징의 사전 검사에 의한 영상 벡터양자화의 고속 부호화 기법)

  • Ryu Chul-hyung;Ra Sung-woong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.12C
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    • pp.1231-1238
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    • 2005
  • This paper presents a new fast encoding algorithm for image vector quantization that incorporates the partial distances of multiple features with a multidimensional look-up table (LUT). Although the methods which were proposed earlier use the multiple features, they handles the multiple features step by step in terms of searching order and calculating process. On the other hand, the proposed algorithm utilizes these features simultaneously with the LUT. This paper completely describes how to build the LUT with considering the boundary effect for feasible memory cost and how to terminate the current search by utilizing partial distances of the LUT Simulation results confirm the effectiveness of the proposed algorithm. When the codebook size is 256, the computational complexity of the proposed algorithm can be reduced by up to the $70\%$ of the operations required by the recently proposed alternatives such as the ordered Hadamard transform partial distance search (OHTPDS), the modified $L_2-norm$ pyramid ($M-L_2NP$), etc. With feasible preprocessing time and memory cost, the proposed algorithm reduces the computational complexity to below the $2.2\%$ of those required for the exhaustive full search (EFS) algorithm while preserving the same encoding quality as that of the EFS algorithm.

Evaluation of a Grid System for Numerical Analysis of a Small Savonius Wind Turbine (사보니우스 소형풍력터빈 수치해석용 격자시스템 평가)

  • KIM, CHUL-KYU;LEE, SANG-MOON;JEON, SEOK-YUN;YOON, JOON-YONG;JANG, CHOON-MAN
    • Journal of Hydrogen and New Energy
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    • v.27 no.5
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    • pp.547-553
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    • 2016
  • This paper presents the effect of a grid system on the performance of a small Savonius wind turbine installed side-by-side. Turbine performance is compared using three different grid systems; tetrahedral grid having a concentrated circular grid around turbine rotors, the tetrahedral grid having a concentrated rectangular grid around turbine rotors and the symmetric grid having a concentrated tetrahedral grid near the turbine rotor blades and a hexahedral grid. The commercial code, SC/Tetra has been used to solve the three-dimensional unsteady Reynolds-averaged Navier-Stokes analysis in the present study. The Savonius turbine rotor has a rotational diameter of 0.226m and an aspect ratio of 1.0. The distance between neighboring rotor tips keeps the same length of the rotor diameter. The variations of pressure and power coefficient are compared with respect to blade rotational angles and rotating frequencies of the turbine blade. Throughout the comparisons of three grid systems, it is noted that the symmetric grid having a concentrated tetrahedral grid near the turbine rotor blades and a hexahedral grid has a stable performance compared to the other ones.

Numerical study on buckling of steel web plates with openings

  • Serror, Mohammed H.;Hamed, Ahmed N.;Mourad, Sherif A.
    • Steel and Composite Structures
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    • v.22 no.6
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    • pp.1417-1443
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    • 2016
  • Cellular and castellated steel beams are used to obtain higher stiffness and bending capacity using the same weight of steel. In addition, the beam openings may be used as a pass for different mechanical fixtures such as ducts and pipes. The aim of this study is to investigate the effect of different parameters on both elastic and inelastic critical buckling stresses of steel web plates with openings. These parameters are plate aspect ratio; opening shape (circular or rectangular); end distance to the first opening; opening spacing; opening size; plate slenderness ratio; steel grade; and initial web imperfection. The web/flange interaction has been simplified by web edge restraints representing simply supported boundary conditions. A numerical parametric study has been performed through linear and nonlinear finite element (FE) models, where the FE results have been verified against both experimental and numerical results in the literature. The web plates are subject to in-plane linearly varying compression with different loading patterns, ranging from uniform compression to pure bending. A buckling stress modification factor (${\beta}$-factor) has been introduced as a ratio of buckling stress of web plate with openings to buckling stress of the corresponding solid web plate. The variation of ${\beta}$-factor against the aforementioned parameters has been reported. Furthermore, the critical plate slenderness ratio separating elastic buckling and yielding has been identified and discussed for two steel grades of DIN-17100, namely: ST-37/2 and ST-52/3. The FE results revealed that the minimum ${\beta}$-factor is 0.9 for web plates under uniform compression and 0.7 for those under both compression and tension.

A Study on the Performance of Digital Subscriber Line in Gaussian and Far-end Crosstalk Noises Environment Using Semi-analytic Simulation (Semi-analytic 시뮬레이션을 이용한 가우스 및 원단누화 잡음환경에서의 디지털가입자라인의 BER 성능에 관한 연구)

  • 채윤식;강영홍;이정식;김용환;조평동
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 1999.11a
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    • pp.390-394
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    • 1999
  • In this paper, we have evaluated BER performance of digital subscriber line(DSL) using the twisted-pair channel model by means of Semi-analytic simulation technique. As a result, it was known that the Semi-analytic simulation was proved to be a good technique because of the attenuation of 0.5dB. To keep the BER=10$\^$-7/, 4dB of E$\^$b//N$\^$0/ is needed more when the DSL length extends to 5000m, while 2dB increase of E$\^$b//N$\^$0/ is required when Nyquist frequency goes to 512kb/s with the keeping same distance. In addition, the effect by FEXT noise is serious, when the FEXT noise damping constant, k is over 10/sup-10/ in DSL length and 10$\^$-14/ in the aspect of Nyquist frequency. As the basic, results of this analysis can be used in setting in internal and external standardization of DSL system in the future.

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