• Title/Summary/Keyword: 최소자승

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Effects of Urban Environments on Pedestrian Behaviors: a Case of the Seoul Central Area (보행에 대한 도시환경의 차이: 서울 도심을 중심으로)

  • Kwon, Daeyoung;Suh, Tongjoo;Kim, Soyoon;Kim, Brian Hong Sok
    • Journal of Korean Society of Transportation
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    • v.32 no.6
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    • pp.638-650
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    • 2014
  • The objective of this study is to identify the causes of pedestrian volume path to the destination by investigating the influential levels of regional and planning features in the central area of Seoul. Regional characteristics can be classified from the result of the analysis and through the spatial characteristics of pedestrian volume. For global scale analysis, Ordinary Least Squares (OLS) regression is used for the degree of influence of each characteristics to pedestrian volume. For the local scale, Geographically Weighted Regression (GWR) is used to identify regional influential factors with consideration for spatial differences. The results of OLS indicate that boroughs with transportation facilities, commercial business districts, universities, and planning features with education research facilities and planning facilities have a positive effect on pedestrian volume path to the destination. Correspondingly, transportation hubs and congested areas, commercial and business centers, and university towns and research facilities in the Seoul central area can be identified through the results of GWR. The results of this study can provide information with relevance to existing plans and policies about the importance of regional characteristics and spatial heterogeneity effects on pedestrian volume, as well as significance in the establishment of regional development plans.

Characteristics of 23 MV Photon Beam from a Mevatron KD 8067 Dual Energy Linear Accelerator (Mevatron KD 8067 선형가속기의 23 MV 광자선의 특성)

  • Kim, Ok-Bae;Choi, Tae-Jin;Kim, Young-Hoon
    • Radiation Oncology Journal
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    • v.8 no.1
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    • pp.115-124
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    • 1990
  • The characteristics of 23 MV photon beam have been presented with respect to clinical parameters of central axis depth dose, tissue-maxi mum ratios, scatter-maximum ratios, surface dose and scatter correction factors. The nominal accelerating potential was found to be $18.5\pm0.5$ MV on the central axis. The half-value layer (HVL) of this photon beam was measured with narrow beam geometry from central axis, and it has been showed the thickness of $24.5\;g/cm^2$. The tissue-maximum ratio values have been determined from measured percentage depth dose data. In our experimental dosimetry, the surface dose of maximum showed only $9.6\%$ of maximum dose at $10\times10\;cm^2$, 100 cm SSD, without blocking tray in. The TMR'S of $0\times0$ field size have been determined to get average $2.3\%$ uncertainties from three different methodis; are zero effective attenuation coefficient, non-ilnear least square fit of TMR's data and effective linear attenuation coefficient from the HVL of 23 MV photon beams of dual energy linear accelerator.

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Evaluation of Beef Freshness Using Visible-near Infrared Reflectance Spectra (가시광선-근적외선 반사스펙트럼을 이용한 쇠고기의 신선도 평가)

  • Choi, Chang-Hyun;Kim, Jong-Hun;Kim, Yong-Joo
    • Food Science of Animal Resources
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    • v.31 no.1
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    • pp.115-121
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    • 2011
  • The objective of this study was to develop models to predict freshness factors (total viable counts (TVC), pH, volatile basic nitrogen (VBN), trimethylamine (TMA), and thiobarbituric acid (TBA) values) and the storage period in beef using a visible and near-infrared (NIR) spectroscopic technique. A total of 216 beef spectra were collected during the storage period from 0 to 14 d at a $10^{\circ}C$ storage. A spectrophotometer was used to measure reflectance spectra from beef samples, and beef freshness spectra were divided into a calibration set and a validation set. Multi-linear regression (MLR) models using the stepwise method were developed to predict the factors. The MLR results showed that beef freshness had a good correlation between the predicted and measured factors using the selected wavelength. The correlation of determination ($r^2$), standard error of prediction (SEP), and ratio of standard deviation to SEP (RPD) of the prediction set for TVC was 0.74, 0.64, and 2.75 Log CFU/$cm^2$, respectively. The $r^2$, SEP, and RPD values for pH were 0.43, 0.10, and 1.10; those for VBN were 0.73, 1.45, and 2.00 mg%; those for TMA were 0.70, 0.19, and 2.58 mg%; those for TBA values were 0.73, 0.13, and 2.77 mg MA/kg; and those for storage period were 0.77, 1.94, and 2.53 d, respectively. The results indicate that visible and NIR spectroscopy can predict beef freshness during storage.

Development of Nondestructive Sorting Method for Brown Bloody Eggs Using VIS/NIR Spectroscopy (가시광 및 근적외선 전투과 스펙트럼을 이용한 갈색 혈란 비파괴선별 방법 개발)

  • Lee, Hong-Seock;Kim, Dae-Yong;Kandpal, Lalit Mohan;Lee, Sang-Dae;Mo, Changyeun;Hong, Soon-Jung;Cho, Byoung-Kwan
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.1
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    • pp.31-37
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    • 2014
  • The aim of this study was the non-destructive evaluation of bloody eggs using VIS/NIR spectroscopy. The bloody egg samples used to develop the sorting mode were produced by injecting chicken blood into the edges of egg yolks. Blood amounts of 0.1, 0.7, 0.04, and 0.01 mL were used for the bloody egg samples. The wavelength range for the VIS/NIR spectroscopy was 471 to 1154 nm, and the spectral resolution was 1.5nm. For the measurement system, the position of the light source was set to $30^{\circ}$, and the distance between the light source and samples was set to 100 mm. The minimum exposure time of the light source was set to 30 ms to ensure the fast sorting of bloody eggs and prevent heating damage of the egg samples. Partial least squares-discriminant analysis (PLS-DA) was used for the spectral data obtained from VIS/NIR spectroscopy. The classification accuracies of the sorting models developed with blood samples of 0.1, 0.07, 0.04, and 0.01 mL were 97.9%, 98.9%, 94.8%, and 86.45%, respectively. In this study, a novel nondestructive sorting technique was developed to detect bloody brown eggs using spectral data obtained from VIS/NIR spectroscopy.

Synthesis and Structural Analysis of Binary Alloy ($MoRu_3$, $MoRh_3$) (이성분계 금속합금($MoRu_3$, $MoRh_3$)의 합성 및 구조분석)

  • Park, Yong Joon;Lee, Jong-Gyu;Kim, Jong Goo;Kim, Jung Suk;Jee, Kwang-Yong
    • Analytical Science and Technology
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    • v.11 no.3
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    • pp.189-193
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    • 1998
  • Binary alloys, $MoRu_3$ and $MoRh_3$, have been prepared using arc melting furnace. Mo and the noble metals Ru and Rh are the constituents of metallic insoluble residues, which were found in the early days of the post-irradiation studies on uranium oxide fuels. Detailed structural informations about these alloys have not been reported on JCPDS files of ICDD (International Centre for Diffraction Data). The results of X-ray diffraction study showed that the alloy was crystallized in hexagonal close-packing, well known as ${\varepsilon}$-phase. The X-ray diffraction patterns of these alloys matched well to that of $WRh_3$ with $P6_3/mmc$ of space group. The lattice parameters, a and c, were calculated using the least squares extrapolation. It was found from X-ray photoelectron spectroscopic measurements that Mo on the surface of the alloy was oxidized to Mo(6+), which could be removed by sputtering with Ar ions for approximately 15 minutes. The changes in binding energy of Mo, Ru, and Rh on the surface of the alloy were not observed. Magnetic susceptibility measurements resulted in the typical Pauli-paramagnetic behavior in the temperature range of 2 to 300 K.

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An Accurate and Efficient Analysis of Composite Plates Based on Enhanced First-order Shear Deformation Theory (개선된 일차전단변형이론을 이용한 복합재료 적층평판의 고정밀 해석)

  • Kim, Jun-Sik;Cho, Maeng-Hyo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.19 no.4 s.74
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    • pp.407-418
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    • 2006
  • In this paper, an efficient yet accurate stress analysis based on the first-order shear deformation theory (FSDT) is presented. The transverse shear strain energy is modified via the mixed variational theorem, so that the shear correction factors are automatically involved in the formulation. In the mixed variational formulation, the transverse stresses are taken to be functions subject to variations. The transverse shear stresses based on an efficient higher order plate theory (EHOPT, Cho and Parmerter, 1993) are utilized and modified, while the transverse normal stress is assumed to be the third-order polynomial of thickness coordinates, which satisfies both zero transverse shear stresses and prescribed surface fractions in top and bottom surfaces. On the other hand, the displacements are assumed to be those of the FSDT Resulting strain energy expressions are referred to as an EFSDTM3D that stands for an enhanced first-order shear deformation theory based on the mixed formulation for three dimensional elasticity, The developed EFSDTM3D preserves the computational advantage of the classical FSDT while allowing for important local through-the-thickness variations of displacements and stresses through the recovery procedure that is based on the least square minimization of in-plane stresses. Comparisons of displacements and stresses of both laminated and sandwich plates using the present theory are made with the classical FSDT, three-dimensional exact solutions, and available data in the literature.

Crystal Structures of Vacuum Dehydrated Fully $Cd^{2+}$-Exchanged Zeolite A and of Its iodine Sorption Complex (카드뮴 이온으로 완전히 치환한 제올라이트 A를 진공 탈수한 구조와 이것에 요오드를 흡착한 결정구조)

  • Jang, Se-Bok;Han, Young-Wook;Kim, Yang
    • Korean Journal of Crystallography
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    • v.4 no.2
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    • pp.54-62
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    • 1993
  • The crystal shnture of dehydrated fully Cd2+-exchanged zeolite A evacuated at 2 × 10-6 Torr and 650℃ (a:12.189(2) A) and of its iodine sorption corrplex (a:12.168(2)A) have been netsmlmn by single uystal x-ray diffraction techliques in the cubic space group hkTn at 21(1)℃. The strutures were refined to final error indices, Ri:0.057 and R2 =0.063 with 186 reflections and Rl:0.082 and R2:0.085 with 181 reflections, respectively, for which 1>3σ(In both structure, six lie at two distinguished threefold axes of unit cell ten the crystal structure of an iodine sorption complex of Cd6-A four Cd2+ ions are recessed 0.69(1) A into the large cavity to complex each with from the (111) plane of 0(3), whereas two Cd2+ ions recessed 0.68(1) A into the sodalite unit Awximately 4.0 l3ions per nit cell are sorbed. Each bridge between a Cd2+ ion and 8-ring oxygens ((I-I-I)= 117(1) ˚ and 0(1)-I(1)-I(2)=172(1)). The near linear I-I-0 angle and its interatomic distance (I-0=3.57(3) A) are indicative of a weak charge transfer interacticn between the frarrework oxygen and iodine. The existence of In3 inside the large cavity indicates that the If ions and H ions may be produced by reaction of In vapor with water molecules which maybe associated with Cd2+ ions in partially dehydrated Cd6-A In3- ions may be produced by the combination of I- and I2.

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The Crytal and Molecular Structure of Morpholinothiosemicarbazide (Morpholinothiosemicarbazide의 結晶 및 分子構造)

  • Chung Hoe Koo;Hoon Sup Kim;Hyun So Shin;Yungja Lee
    • Journal of the Korean Chemical Society
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    • v.17 no.2
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    • pp.105-114
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    • 1973
  • The crystal structure of morpholinothiosemicarbazide has been determined by single crystal X-ray analysis. The lattice constants are a = 4.19(2), b = 6.56(2) and c = 26.67(4)${\AA}$. The unit cell contains 4 molecules and the space group is$P2_12_12_1$. The atomic parameters have been refined by least-squares method to a final R value of 0.07, based on the 651 observed reflexions. The amino nitrogen atom forms hydrogen bonds to the sulfur atoms of the other molecules related by the two-fold screw axis parallel to the a-axis, the distances of the hydrogen bonds being 3.48 and 3.49${\AA}$. On the other hand, the imino nitrogen atom forms a hydrogen bond to the amino nitrogen atom of the other molecule related by the two-fold screw axis parallel to the a-axis, the distance of the hydrogen bond being 3.04${\AA}$. These three hydrogen bonds arrange the molecules around the two-fold screw axis. Apart from the hydrogen bonding system the structure is held together by van der Waals forces.

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The Crystal and Molecular Structure of P-Aminobenzaldehyde Cyclohexylthiosemicarbazone (P-Aminobenzaldehyde Cyclohexylthiosemicarbazone의 결정 및 분자구조)

  • Chung Hoe Koo;Chong Hee Kim;Young Ja Park
    • Journal of the Korean Chemical Society
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    • v.25 no.6
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    • pp.343-350
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    • 1981
  • The crystal and molecular structure of P-aminobenzaldehyde cyclohexylthiosemicarbazone, C14H20N4S, has been determined from 2712 integrated intensities measured on a computer controlled four circle diffractometer with monochromated $CuK_{\alpha}$, X-ray radiation. The crystals are monoclinic, space group C2/c with eight molecules in a unit cell of dimensions, a = 12.488(2), b = 12.276(4), c = 19.997(6)${\AA}$ and ${\beta}=103.55(3)^{\circ}$. The structure was solved by Patterson and Fourier method and refined by a full-matrix least squares method to a final R value of 0.058 for all reflections. The C(8)-S bond is trans to N(2)-N(3) and C(8)-N(1) is cis to N(2)-N(3) bond. The cyclohexane ring has chair conformation and makes an angle of $40.7^{\circ}$ with the benzene ring. The molecules are linked by N(2)H…S hydrogen bonds into dimer-like units which are held together by $N-H{\ldots}N$ hydrogen bonds. Sulfur accepts second rather weak hydrogen bond from N(4). An intramolecular hydrogen bond exists between N(1) and N(3) atoms.

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A Robust Method for Automatic Generation of Moire Reference Phase from Noisy Image (노이즈 영상으로부터 모아레 기준 위상의 강인 자동 생성 방법)

  • Kim, Kuk-Won;Kim, Min-Young
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.5
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    • pp.909-916
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    • 2009
  • This paper presents the automatic vision algorithm to generate and calibrate reference phase plane to improve the accuracy of 3D measuring machine of using phase shifting projection moire method, which is not traditional N-bucket method, but is based on direct image processing method to the pattern projection image. Generally, to acquire accurate reference phase plane, the calibration specimen with well treated surface is needed, and detailed calibration method should be performed. For the cost reduction of specimen manufacturing and the calibration time reduction, on the specimen, not specially designed, with general accuracy level, an efficient calibration procedure for the reference phase generation is proposed. The proposed vision algorithm is developed to extract the line center points of the projected line pattern from acquired images, derive the line feature information consisting of its slope and intercept by using sampled feature points, and finally generate the related reference phase between line pairs. Experimental results show that the proposed method make reference phase plane with a good accuracy under noisy environment and the proposed algorithm can reduce the total cost to make high accurate calibration specimen, also increase the accuracy of reference phase plane, and reduce the complex calibration procedure to move grid via N-bucket algorithm precisely.