• Analytical Science and Technology
• /
• v.28 no.6
• /
• pp.430-435
• /
• 2015

Two-dimensional analysis between the explosive performance and the impact sensitivity for methylnitroimidazole derivatives was performed to understand where these new energetic molecules could be utilized. The explosive performance was analyzed with the Cheetah program, while the impact sensitivity was predicted using neural network analysis. Successive nitration of methylimidazole made the molecule more sensitive, but methyltrinitroimidzole appeared to have a relatively good safety characteristic. We recently developed a novel method to analyze the potential usage of new energetic molecules using a two-dimensional chart, where the explosive performance and the impact sensitivity were located on the X-axis and Y-axis, respectively. An analysis of a two-dimensional plot between the performance and the sensitivity indicated that methyldinitroimidazole would be useful for insensitive explosive formulations, while methyltrinitroimidazole was forecasted for use as an ingredient for high explosive formulations.

• Journal of Energy Engineering
• /
• v.5 no.1
• /
• pp.72-79
• /
• 1996

The effect of controllers-Exciter, Power System Stabilizer, and Static Var Compensator-in one machine infinite bus system is investigated in this paper. The structure of generator state matrix with controllers is represented, while the Static Var Compensator is installed in generator terminal bus. Eigen-value analysis is performed and the effects of controllers to the dominant eigenvalue in one machine infinite bus system are represented by first order eigenvalue sensitivity coefficients while the operating conditions of the system are varied. Optimization of controller parameters using first order eigenvalue sensitivity coefficients is performed by the Simplex Method. It is proved that exciter control is the most efficient method to improve stability of the system and the effect of Static Var Compensator is small, in the case of one machine infinite bus system.

• Journal of the Society of Naval Architects of Korea
• /
• v.35 no.3
• /
• pp.54-61
• /
• 1998

This paper presents a prediction method of natural frequencies of vertical hull girder vibration based on design sensitivity analysis in case of design modification and the variation of loading condition. The resented method premises the vibration analysis by the transfer matrix method. Governing sensitivity equation is derived from the direct differentiation of state vector and transfer matrix to parameters and its transfer over all the hull girder elements. Derivatives of natural frequencies and mode shapes are determined by two trial calculation of the governing equation. Using the derivatives, the changes of natural frequencies and mode shapes can be predicted when mass and stiffness parameter's are changed. As results, it is possible to optimize ship structure as well as to avoid troublesome calculation in hull girder vibration analysis rationally and efficiently. To verify the accuracy and efficiency of the resented method numerical results obtained by both the sensitivity analysis and the ordinary reanalysis far a real ore/bulk carrier in case of the change of mass and stiffness parameters are compared.

• Korean Journal of Optics and Photonics
• /
• v.24 no.2
• /
• pp.86-91
• /
• 2013

In this study, we have investigated the correlation of far-field detection sensitivity of surface plasmon resonance (SPR) biosensors with optical signatures associated with the near-field overlap of biomolecules. The results confirm a direct relation between the far-field and near-field parameters, particularly for optical signatures defined in terms of lateral electric field components that are tangential to the interface and thus continuous across the interface. The overall correlation between near-field optical signatures and far-field resonance shift exceeded 97%. The results can be highly useful to evaluate detection sensitivity of SPR biosensors that take advantage of complex structures for localization of surface waves.

• Journal of Ocean Engineering and Technology
• /
• v.13 no.4 s.35
• /
• pp.10-18
• /
• 1999

본 논문에서는 대형구조물의 해석에 있어서 부분구조합성법과 섭동법을 이용하여 복잡한 비선형시스템의 해석방법을 제안하였다. 해석방법은 전체시스템을 먼저 몇 개의 분계로 분할한다. 각 분계의 운동방정식에 비선형항이 존재하여도 전체시스템의 지배적 진동모드는 선형모드라는 가정하에 이 시스템의 각 분계를 모드좌표로 변환한다. 이때, 비선형항은 근사적으로 변환한다. 그리고 섭동법을 이용하여 각 분계의 모드좌표방정식은 섭동좌수별로 정식화되어 순차적으로 구해진다. 비선형의 감도는 비선형계수로 정의되고, 그에 상응하는 강성에 의해 구해진다. 제안된 해석방법으로 비선형회전체, 비선형 베어링-페데스탈로 구성된 대형시계구조물의 진동을 해석하였다. 해석방법의 유효성을 평가하기 위해 응답의 정도와 계산소요시간을 유한요소법의 결과와 비교 분석하였다.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.34 no.1
• /
• pp.73-78
• /
• 2010

Estimation of tensile properties measurement uncertainty of material was carried out. Sources of uncertainty affecting the measurement of tensile properties were classified and analyzed. The models for uncertainty evaluation of measurands to be determined from tensile test, such as elastic modulus, yield strength and tensile strength, were suggested and derived from the mathematical relations, corresponding to the respective measurands, and the measuring quantities by calculating each sensitivity coefficient of the quantities. Based on these models, the uncertainty of the tensile properties was evaluated from the experimental data of SUS316LN determined according to ISO 6892.

• Journal of Sensor Science and Technology
• /
• v.8 no.4
• /
• pp.308-313
• /
• 1999

This paper will present an anisotropic etching in TMAH technique used in the fabrication of three-dimensional magnetic field vector sensor based on angled Hall plate structure. This sensor design relies on simultaneously detecting all magnetic field vector components using Hall plates that are imbedded into the silicon [111] sloped-surface of bulk micromachined cavity by the anisotropic etching of [100] silicon. The fabricated Hall elements has relatively improved sensitivity compare to convensional Hall elements for three-dimensional magnetic field sensing. The product sensitivity of 547V/AT at the supply current of 1.0mA was achived. The corresponding limit in the detection of magnrtic field is 0.07G that calculated by measured power spectral density(PSD) in magnetic sensor output.

• Applied Chemistry for Engineering
• /
• v.5 no.4
• /
• pp.662-668
• /
• 1994

The cinnamoyl esters of polyresorcinol-formaldehyde glycidyl ether (RGEFC) with photosensitive functional group were prepared. Photosensitivity of RGEFC were investigated by the change of solubility before and after exposure to light. Various samples coated on glass plates were exposed to light under various conditions and steeped in the same solvent as used for coating, and then the yield of residual film was calculated. The yield of the residual film which was closely related to the sensitivity of the film, was affected by the degree of polymerization of the backbone resin, sensitizers and their concentration. The sensitivity was depended upon the degree of polymerization. Most effective sensititizer for RGEFC among the sensitizers used was 2,6-dichloro-4-nitroaniline.

• Journal of the Korean Society of Propulsion Engineers
• /
• v.17 no.6
• /
• pp.97-104
• /
• 2013

N-Guanylurea dinitramide (GUDN) is an energetic material with low sensitivities and good performance for use as propellants or insensitive munitions explosives. The efficient synthesis and characterization of high energy density material of GUDN is reported. GUDN was characterized spectroscopically as well as elemental analysis. In addition, the heats of formation were calculated with the Gaussian 09 suite of programs. For initial safety testing, the impact sensitivity and the friction sensitivity were tested following BAM procedure.

• Nuclear Engineering and Technology
• /
• v.20 no.2
• /
• pp.71-79
• /
• 1988

Published data of the efficiency of CR-39 detectors as a function of neutron energy from different laboratories show wide variations in the response obtained. These variations result from differences in etching conditions, in the materials and thickness of the radiator, in the sensitivities of CR-39 from different manufacturers and perhaps in criteria used for the size of spots that are counted. This paper describes some effects of these factors on the energy and angular response with calculational results. Calculated and measured results of the variations of response with neutron incident angie are more consistent than those of energy response. The data calculated show that the angular response is not a strong function of neutron energy except below about 0.3 MeV.