• Title/Summary/Keyword: correlation distance

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What Is the Ideal Entry Point for Transforaminal Endoscopic Lumbar Discectomy?

  • Lee, Jong Un;Park, Ki Jeoung;Kim, Ki Hong;Choi, Man Kyu;Lee, Young Hwan;Kim, Dae-Hyun
    • Journal of Korean Neurosurgical Society
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    • v.63 no.5
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    • pp.614-622
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    • 2020
  • Objective : The method of approach during transforaminal endoscopic lumbar discectomy (TELD) has been the subject of repeated study. However, the ideal entry point during TELD has not been studied in detail. Therefore, this study investigated the ideal entry point for avoiding complications using computed tomography (CT) scans obtained from patients in the prone position. Methods : Using CT scans obtained from patients in the prone position, we checked for retroperitoneal or visceral violations and measured the angles of approach with five conventional approach lines drawn on axial CT scans at each disc space level (L2-3, L3-4, and L4-5). We also determined the ideal entry point distance and approach angles for avoiding retroperitoneal or visceral violations. Correlation analysis was performed to identify the patient characteristics related to the ideal entry point properties. Results : We found that the far lateral approach at the L2-3 level resulted in high rates of visceral violation. However, rates of visceral violation at the L3-4 and L4-5 levels were remarkably low or absent. The ideal angles of approach decreased moving caudally along the spine, and the ideal entry point distances increased moving caudally along the spine. Weight, body mass index (BMI), and the depth of the posterior vertebral line from the skin were positively associated with the distance of the ideal entry point from the midline. Conclusion : We reviewed the risk of the extreme lateral approach by analyzing rates of retroperitoneal and visceral violations during well-known methods of approach. We suggested an ideal entry point at each level of the lumbar spine and found a positive correlation between the distance of the entry point to the midline and patient characteristics such as BMI, weight, and the depth of the posterior vertebral line from the skin.

Heavy Metals in Paddy Rice and Soils in Mangyeong River Area (만경강(萬頃江) 유역(流域)의 토양(土壤) 및 수도체중(水稻體中) 중금속(重金屬) 함량(含量))

  • Kim, Seong-Jo;Ryang, Hwan-Seung
    • Korean Journal of Environmental Agriculture
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    • v.5 no.1
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    • pp.11-23
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    • 1986
  • Soils and rice plants in wastewater irrigated area of the Mangyeong River receiving waster from the Jeonju Industrial Complex and municipal sewage were sampled at two depths to assess the nature and content of Cd, Cu, Pb and Zn, particularly with respect to distance from wastewater source. For metal levels of soils in these area, no difference in the heavy metal contents between the surface and the subsurface soils was found. Total contents of Cu, Pb and Zn in soils were negatively correlated with distance from the source. A positive correlation was found between contents of total and 0.1N-HCl extractable or $1N-CH_3COONH_4$ extractable heavy metals in surface soils of these area. Total contents of heavy metals in soils were positively correlated with clay, soil organic matter and cation exchange capacity. Heavy metal contents of brown rice sampled at the Jeon-ju Industrial Complex area ranged from 0.15 to 0.91 ppm for Cd, from 1.13 to 5.68 ppm for Cu, from 0.22 to 7.16 ppm for Pb and from 11.74 to 38.66 ppm for Zn. Negative correlation was found between the contents of Cd, Cu, Pb, and Zn in the brown rice and the distance from the source. The contents of Cd, Cu and Zn in rice straw were positively correlated with those in the brown rice.

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Determination of the Optimal Mixture Ratio for Extrudates of Job's-tear and Wheat Flour by Mixture Design Analysis (혼합실험계획법에 의한 율무와 밀가루의 압출성형 최적 배합 조건 설정)

  • Cho, Seok-Cheol;Kang, Byung-Sun
    • Korean Journal of Food Science and Technology
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    • v.45 no.4
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    • pp.473-477
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    • 2013
  • The aim of this study was to identify the optimal ingredient-mixing ratio of Job's-tear and wheat flour subjected to extrusion. A modified distance-based mixture design analysis was chosen for the experimental design. The results showed that the bending failure force, the a-value, and the water absorbtion index (WAI) value had no correlation with the mixture ratio of Job's-tear and wheat flour. However, the diameter of the extrudates, the L- and b-values, and the water solubility index (WSI) value were all found to be correlated to the mixture ratio. While the first three values were determined using a linear model, the WSI value was determined using a quadratic model. The diameter and color had an inverse correlation to the mixture ratio: the higher the ratio of Job's-tear to wheat flour, the lower the diameter and darker the color. The L- and b-values were found to change in accordance with the mixture ratio of Job's-tear to wheat flour. The lowest WSI value was obtained at a 40:60 ratio of Job's-tear to wheat.

The Applicability of Minimum Entropy Deconvolution Considering Spatial Distribution of Sampling Points (지하수 함양량 추정시 공간상에서의 자료 Sampling 방법에 따른 Minimum Entropy Deconvolution의 적용성에 관한 검토)

  • Kim Tae-Hee;Kim Yong-Je;Lee Kang-Keun
    • Journal of Soil and Groundwater Environment
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    • v.11 no.3
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    • pp.52-58
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    • 2006
  • Kim and Lee (2005) suggested Minimum Entropy Deconvolution (MED) to estimate the temporal sequence of the relative recharge. However this study by Kim and Lee (2005) was just related to the verification of the conceptual approach with MED. In this study, we try to characterize the applicability of MED in the case of spatially heterogeneous recharge (distance from recharge area). Simulated results were recorded with some specific sampling points. Estimated results from this study show higher than 0.8 in cross-correlation with the original recharge sequence. In addition, the physical and mathematical meanings of the applied filter length was also investigated. It was revealed that the length of filter is highly related to the spatial distance between recharge area and the monitoring site, and the apparent shape of hydraulic head change.

Studies on the Heavy Metals in Paddy Rice and Soils in Jang-hang Smelter (제연소인근지역(製鍊所隣近地域)의 토양(土壤) 및 수도체중(水稻體中) 중금속함량(重金屬含量)에 관(關)한 조사연구(調査硏究))

  • Kim, Seong-Jo;Ryang, Hwan-Seung
    • Korean Journal of Soil Science and Fertilizer
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    • v.18 no.4
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    • pp.336-347
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    • 1985
  • Soils and rice plants subject to smoke from the Jang-hang Smelter were samples at two depths to assess the nature and extend of Cd, Cu, Pb, and Zn contamination, particularly with respect to distance from pollution source. Soils at east site within 1km of the center of the smelter were highly contaminated with Cd, Cu, Pb, and Zn. Metal levels in the smoke-polluted area were higher in surface soil than in subsurface soil, and decreased rapidly with distance reaching nearly background levels at 5km from pollution source. A position correlation was found between contents of total and 0.1 N HCl-extractable, or 1.0N $CH_3COONH_4$- extractable heavy metals in surface soils of pollution. Contents of heavy metals in soils were positively correlated with soil organic matter and cation exchange capacity. The contents of heavy metals in brown rice collected from the paddy field around the Jang-hang Smelter were in the range of 0.23-1.33 ppm for Cd, 2.39-6.25 for Cu, 0.95-8.32 ppm for Pb and 14.60-27.31 for Zn. The contents of Cd, Cu, and Zn in rice straw were positively correlated with those in the brown rice. Negative correlation was found between the contents of Cd, Cu, Pb, and Zn in brown rice and the distance from the source.

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The Min-Distance Max-Quantity Assignment Algorithm for Random Type Quadratic Assignment Problem (랜덤형 2차원 할당문제의 최소 거리-최대 물동량 배정 알고리즘)

  • Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.18 no.3
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    • pp.201-207
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    • 2018
  • There is no known polynomial time algorithm for random-type quadratic assignment problem(RQAP) that is a NP-complete problem. Therefore the heuristic or meta-heuristic approach are solve the approximated solution for the RQAP within polynomial time. This paper suggests polynomial time algorithm for random type quadratic assignment problem (QAP) with time complexity of $O(n^2)$. The proposed algorithm applies one-to-one matching strategy between ascending order of sum of distance for each location and descending order of sum of quantity for each facility. Then, swap the facilities for reflect the correlation of distances of locations and quantities of facilities. For the experimental data, this algorithm, in spite of $O(n^2)$ polynomial time algorithm, can be improve the solution than genetic algorithm a kind of metaheuristic method.

One-way vehicle relocate car-sharing system analysis : Revenue improvement verified in accordance with the event (One-way 차량 재배치 카셰어링 시스템 분석 : 이벤트에 따른 수익 개선 효과 검증)

  • Kim, Woong;Lee, Chul-Ung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8791-8799
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    • 2015
  • In this paper, One-way car-sharing System represents the verification system consider events in revenue effects. Revenue which the time and distance represented the graph, compare one-way vehicle relocate car-sharing system which proven in existing international papers with one-way vehicle relocate car-sharing system consider the event currently in the Korea. Especially, The maximum profit according to the distance and time were assessed through multiple linear regression analysis, and there are probable maximum loss allow for the maximum loss. The company suggested using the event as a discount coupon to customers through various marketing strategies, and then focused on increasing customer demand. So, Correlation analysis to determine the maximum revenue of the actual travel distance and time were carried out through Non-linear Regression.

Design of Diversity Vehicle Antennas for FM Radio Reception (FM 라디오 수신을 위한 차량용 다이버시티 안테나 설계)

  • Ahn, Seung-Beom;Noh, Young-Ho;Oh, Jung-Hoon;Choo, Ho-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.20 no.8
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    • pp.761-769
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    • 2009
  • In this paper, we report on the channel capacity and diversity gain of the vehicle on-glass antenna for FM radio reception. The correlation coefficient and channel capacity were obtained using the simulated 3D radiation pattern of each antenna and the Rayleigh channel model for urban environment. To examine the channel capacity we used two antennas which are a simple straight antenna and L-type antenna. Then we observed the available channel capacity by varying the position of feeds and the shape of the L-type antenna. The sample antenna, which has a maximum feed distance with different polarizations, was built and the receiving performance was measured in the weak FM field area. From the results we confirmed that the distance between the feeds should be placed as far as possible for the high channel capacity. If the distance between the feeds are greater than a certain threshold value than the polarizations of the two antennas are getting more important for determining the channel capacity.

Structures and N→Si Bond Characters of 1-Fluorosilatrane and the Silatranyl Cation

  • Lee, Hyo-Sug;Bae, Cheol-Beom;Do, Young-Kyu;Lee, Yoon-Sup
    • Bulletin of the Korean Chemical Society
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    • v.23 no.2
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    • pp.215-220
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    • 2002
  • The structures of 1-fluorosilatrane and the silatranyl cation were calculated by Hartree-Fock (HF), Mofller-Plesset second order (MP2), and various density functional theory (DFT) methods using many different basis sets, demonstrating that the Si-N bonds in two species are quite different. The N${\rightarrow}$Si bond distance of 1-fluorosilatrane from the hybrid DFT calculations $({\sim}2.32{\AA})$ using the Perdew-Wang correlation functional agrees with the gas phase experimental value $(2.324{\AA})$, while other functionals yield larger distances. The MP2 bond distance (2.287${\AA}$ with 6-311$G^{\ast}$) is shorter, and the HF one (2.544 ${\AA}$ with 6-311$G^{\ast}$) larger than those of DFT calculations. The MP2 bond distance is in good agreement with experiment indicating that the electron correlations are crucial for the correct description of the N${\rightarrow}$Si interaction. The silatranyl cation is a stable local minimum on the potential energy surface in all methods employed suggesting that the cation could be a reaction intermediate. The Si-N bond length for the cation is about 1.87 ${\AA}$ for all calculations tested implying that the Si-N bond is mainly conventional. Bonding characteristics of the Si-N bond in two species derived from the natural bond orbital analysis support the above argument based on calculated bond lengths.

Monitoring Pig Body Temperature Using Infrared Sensors

  • Jang, Jin Cheol;Lee, Min Ho;Lee, Jun Yeop;Choi, Hee Chul;Choi, Dong Yun;Kim, Hyeok Ju;Kim, Hyeon Tae
    • Journal of Biosystems Engineering
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    • v.40 no.4
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    • pp.368-372
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    • 2015
  • Purpose: The purpose of this study is to verify the feasibility of using an infrared sensor to measure the body temperature of a sow. We first conducted experiments on three pigs by using three infrared sensors and one indoor temperature sensor. Methods: The three infrared sensors were installed inside our model house and were used to take temperature measurements per second of the backs of the pigs. While feeding, the temperatures of the backs of the pigs were measured at distances of 10 cm, 20 cm, and 30 cm from the infrared sensors. Results: We concluded that the relation between the temperature of the pigs' backs and the indoor temperature was y =0.549x + 18.459 at a measuring distance of 30 cm. The relation was y = 0.645x + 15.461 for a distance of 20 cm and y = 0.760x + 11.913 for a distance of 10 cm. We found high correlation between the indoor temperature and the temperature of the pigs' backs. Conclusions: It is possible to use an infrared thermometer to monitor the temperature of pigs' backs. This system seems to be feasible and effective in monitoring pig temperature. The use of an infrared thermometer will also make daily monitoring easy. In later experiments, the possibility of developing a system that can determine if an error can be corrected by using infrared sensor is explored by considering humidity variables.