• Title/Summary/Keyword: methods:analytical

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Latent fingerprint development from rubber gloves using MMD I (Multimetal deposition I)

  • An, Jaeyoung;Kim, Heesu;Oh, Jungmin;Han, Sooyong;Yu, Jeseol
    • Analytical Science and Technology
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    • v.33 no.2
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    • pp.108-114
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    • 2020
  • Gloves are very important evidence at a crime scene; specifically, rubber gloves can be found easily at homes. Therefore, crime scene investigators attempt to develop fingerprints inside the rubber gloves that are discovered, for identifying unknown suspects. This study compared the effectiveness of three different methods that are used for developing latent prints on gloves with aging time. These were the powder, cyanoacrylate fuming, and multi-metal deposition I methods. The powder method achieved good results for 1-3 days of aged prints, and the cyanoacrylate fuming method worked well on 2-week-old prints. In comparison, multi-metal deposition I method developed good quality fingerprints for 6 weeks of aging time.

Free Vibration of Primary-Secondary Structures with Multiple Connections (다중 지지된 주-부 구조물의 자유 진동)

  • 민경원
    • Computational Structural Engineering
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    • v.4 no.4
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    • pp.97-106
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    • 1991
  • The frequency window method has been extended to include strong coupling and multiple connections between the primary structure and the secondary structures. The rational polynomial expansion of the eigenvalue problem and the analytical methods for its solution are novel and distinguish this work from other eigenvalue analysis methods. The key results are the identification of parameters which quantify the resonance and coupling characteristics; the derivation of analytical closed-form expressions describing the fundamental modal properties in the frequency windows; and the development of an iterative procedure which yields accurate convergent results for strongly-coupled primary-secondary structures.

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Load Transfer Mechanism between Rafter and Cross-beam by 2-D Analysis (이차원해석에 의한 서까래 도리 사이의 하중전달 메카니즘)

  • Jung, Sung-Jin;Hong, Sung-Gul;Kim, Nam-Hee;Lee, Young-Wook;Hwang, Jong-Kook;Joo, Seok-Jun
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2007.04a
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    • pp.229-234
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    • 2007
  • In the structural analysis of the Korean traditional wooden structure, while the understanding of the transfer mechanism of roof load is very important, there are few researches on this subject. So, some modeling methods considering the connecting methods of the Korean traditional wooden structure are suggested, the results using each modeling method are compared, and the most reasonable analytical model is presented in this study.

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Analysis and Applications of Multi-user DS-PAM and TH-PPM UWB System (다중 사용자 환경에서의 DS-PAM과 TH-PPM UWB 시스템의 분석과 응용)

  • Sung, Tae-Kyung;Kim, Dong-Seek;Kim, Cheol-Seong;Cho, Hyung-Rae
    • Journal of Advanced Marine Engineering and Technology
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    • v.32 no.4
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    • pp.603-610
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    • 2008
  • In this paper, analytical methods for calculating the average probability of bit error of direct sequence pulse amplitude modulation ultra wideband (DS-PAM UWB) system and time hopping pulse position modulation ultra wideband (TH-PPM UWB) system are given. For the multi-user DS-PAM UWB system, the bipolar pulse amplitude modulation is used in order to achieve better performance. As we know, more attention is paid to the TH-PPM UWB systems recently. In this paper. we first introduce the accurate BER calculation methods of the multi-user DS-PAM UWB and TH-PPM UWB systems and then give the performance analysis over the ideal AWGN channel and a correlation receiver. Furthermore, we also introduce their applications in image transmission and data transmission and give the simulation results. The analytical method yields simple and exact formulas relating the performance to the system parameters.

Rapid Method for Seperation and Quantitation of p-Nitrophenol Derivative by HPLC (p-Nitrophenol 유도체의 HPLC에 의한 신속 분리 정량)

  • 이완구
    • Journal of Environmental Health Sciences
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    • v.9 no.1
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    • pp.89-93
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    • 1983
  • Various analytical methods for p-Nitrophenol derivatives have been reported as follows. 1) Thin-Layer Chromatography, 2) Gas Chromatography, 3) Cholinesterase Activity Determination, 4) Diazo Method, 5) Nitrophenol Method, 6) Indophenol Method. But these methods are mainly analyse total quantity of p-Nitrophenol and are not available for the seperation and pose some analytical problems associated with extensive clean up procedure. A rapid and simple method was developed for the seperation and quantitation for the p-Nitrophenol and it's derivatives by HPLC. Also an experiment was undertaken by the authors for the quantitation of the p-Nitrophenol in the blood of the intoxicated body. Levels of p-Nitrophenol ranging from approximately 0.10 to $1.69 \mu g/ml$ for Parathion and $3.44 \mu g/ml$ for EPN in each sample were measured with the average recovery of $95.5\pm0.52%$

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Principles and application of SNIF-NMR

  • Kwon, Hyeok;Son, Woo Sung
    • Journal of the Korean Magnetic Resonance Society
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    • v.23 no.4
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    • pp.98-103
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    • 2019
  • SNIF-NMR is one of the analytical methods used to discriminate impurities in food and natural products. To determine the origin of compounds, SNIF-NMR utilizes frequency of deuterium in site specific fractionated sample using nuclear magnetic resonance. Also, SNIF-NMR is currently used to evaluate the authenticity of various foods such as wine, vanillin and oil, and is known to provide more accurate information than other analytical methods. In this review, the basic principles and practical examples of SNIF-NMR is presented.

A Study on the Total Drag Estimation for the Aircraft Conceptual Design (항공기 개념설계를 위한 전체항력 예측에 관한 연구)

  • 김상진;전권수;이재우
    • Journal of the Korea Institute of Military Science and Technology
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    • v.2 no.2
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    • pp.70-82
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    • 1999
  • During the aircraft conceptual design stage, rapid aerodynamic analyses over various configurations are required. Hence, empirical and analytical methods play important roles in predicting the aero-dynamic characteristics. In this study, total drag estimation method based on empirical and analytical approaches is developed. By comparing with the results of the wind tunnel experiment and existing prediction methods, it is demonstrated that the developed method is accurate and useful in predicting total drag for the whole Mach number range.

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A semi-analytical FE method for the 3D bending analysis of nonhomogeneous orthotropic toroidal shells

  • Wu, Chih-Ping;Li, En
    • Steel and Composite Structures
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    • v.39 no.3
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    • pp.291-306
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    • 2021
  • Based on Reissner's mixed variational theorem (RMVT), the authors develop a semi-analytical finite element (FE) method for a three-dimensional (3D) bending analysis of nonhomogeneous orthotropic, complete and incomplete toroidal shells subjected to uniformly-distributed loads. In this formulation, the toroidal shell is divided into several finite annular prisms (FAPs) with quadrilateral cross-sections, where trigonometric functions and serendipity polynomials are used to interpolate the circumferential direction and meridian-radial surface variations in the primary field variables of each individual prism, respectively. The material properties of the toroidal shell are considered to be nonhomogeneous orthotropic over the meridianradial surface, such that homogeneous isotropic toroidal shells, laminated cross-ply toroidal shells, and single- and bi-directional functionally graded toroidal shells can be included as special cases in this work. Implementation of the current FAP methods shows that their solutions converge rapidly, and the convergent FAP solutions closely agree with the 3D elasticity solutions available in the literature.

Probabilistic seismic risk assessment of simply supported steel railway bridges

  • Yilmaz, Mehmet F.;Caglayan, Barlas O.;Ozakgul, Kadir
    • Earthquakes and Structures
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    • v.17 no.1
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    • pp.91-99
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    • 2019
  • Fragility analysis is an effective tool that is frequently used for seismic risk assessment of bridges. There are three different approaches to derive a fragility curve: experimental, empirical and analytical. Both experimental and empirical methods to derive fragility curve are based on past earthquake reports and expert opinions which are not suitable for all bridges. Therefore, analytical fragility analysis becomes important. Nonlinear time history analysis is commonly used which is the most reliable method for determining probabilistic demand models. In this study, to determine the probabilistic demand models of bridges, time history analyses were performed considering both material and geometrical nonlinearities. Serviceability limit states for three different service velocities were considered as a performance goal. Also, support displacements, component yielding and collapse limits were taken into account. Both serviceability and component fragility were derived by using maximum likely hood methods. Finally, the seismic performance and critical members of the bridge were probabilistically determined and clearly presented.

Recent Trends of Hyperspectral Imaging Technology (초분광 이미징 기술동향)

  • Lee, M.S.;Kim, K.S.;Min, G.;Son, D.H.;Kim, J.E.;Kim, S.C.
    • Electronics and Telecommunications Trends
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    • v.34 no.1
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    • pp.86-97
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    • 2019
  • Over the past 30 years, significant developments have been made in hyperspectral imaging (HSI) technologies that can provide end users with rich spectral, spatial, and temporal information. Owing to the advances in miniaturization, cost reduction, real-time processing, and analytical methods, HSI technologies have a wide range of applications from remote-sensing to healthcare, military, and the environment. In this study, we focus on the latest trends of HSI technologies, analytical methods, and their applications. In particular, improved machine learning techniques, such as deep learning, allows the full use of HSI technologies in classification, clustering, and spectral mixture algorithms. Finally, we describe the status of HSI technology development for skin diagnostics.