• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.1545-1548
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• 1997

A Force-refecting hand controller can provide the kinesthetic information obtained from a slave manipulator to the operator of a teleoperation system. This thesis presents the desgn and the analysis of a 6-degree-of-freedom force-reflecting hand controller using fivebar parallel mechanism. The goal of this thesis is to construct a superior hand controller that can provide large workspace and good force-reflecting ability. The forward kinematics of the fivebar paprallel mechanism has been calculated in real-time using three pin-joint sensors in addition to six actuator position sensors. A force decomposition approach is used to comput the Jacobin. To analyze the characteristics of the fivebar parallel mechanism, it has been compared with the other three parallel mechanisms in terms with workspace and manipulability measure. The force-reflecting hand controller using the fivebar parallel mechanism has been constructed and tested to verify the feasibility of the design concept.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.3
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• pp.288-296
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• 1999

A force-reflecting hand controller can provide the kinesthetic information obtained from a slave manipulator to the operator of a teleoperation system. The goal is to construct a compact hand controller that can provide large workspace and good force-reflecting capability. This paper presents the design and the analysis of a 6-degree-of-freedom force-reflecting hand controller using fivebar parallel mechanism. The forward kinematics of the fivebar parallel mechanism has been calculated in real-time using three pin-joint sensors in addition to six actuator position sensors. A force decomposition approach is used to compute the Jacobian. To evaluate the characteristics of the fivebar parallel mechanism, it has been compared with the other three parallel mechanisms in terms with workspace and manipulability measure. The hand controller using the fivebar parallel mechanism has been constructed and tested to verify the feasibility of the design concept.

• Journal of the Korea Institute of Military Science and Technology
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• v.15 no.1
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• pp.81-85
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• 2012

This work is related to study the thermal decomposition of 1,3,5-trinitro-1,3,5-triazacylohexane(RDX) by differential scanning calorimeter and thermo-gravimetry with Kissinger's & Iso-conversional method under nonisothermal conditions, with heating rate from 2 to $8^{\circ}C$/min or given heating rate. We calculated and compared activation energy with these two methods. Iso-conversional method is better than Kissinger's method to study decomposition mechanism. We also investigated activation energy and frequency factor by Kissinger's & Iso-conversional method with the influence of particle size. In case of single crystal, Cl-3(large crystal) has better thermal stability than Cl-5(small crystal). The activation energy increased according to the size of the particle size.

• Wind and Structures
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• v.3 no.2
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• pp.97-115
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• 2000

The technique of proper orthogonal decomposition is potentially useful in specifying the fluctuating surface pressure field around structures. However there has been a degree of controversy over whether or not the calculated modes have physical meanings. This paper addresses this issue through consideration of the results of full scale experiments, and through an analytical investigation. It is concluded that the lower, most energetic modes are likely to reflect different fluctuating flow mechanisms, although no mode is likely to be associated with just one flow mechanism or vice versa. The higher, less energetic modes are likely to represent interactions between different flow mechanisms, and to be significantly affected by the number of measurement points and measurement errors. The paper concludes with a brief description of the application of POD to the problem of building ventilation, and the calculation of cladding pressures.

• Proceedings of the Membrane Society of Korea Conference
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• 1995.04a
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• pp.1-4
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• 1995

The microstructure of polymer membranes produced via thermally induced phase separation (TIPS) of polymer solutions is a strong function of both the early-stage (by spinodal decomposition or nucleation & growth) and the late-stage phase separation (referred to in general as coarsening). In the case of early stage effects, the membrane morphology resulting from a nucleation & growth mechanism is either a poorly interconnecsed, stringy, beady structure which is mechanically fragile or a well interconnected structure with highly nonuniform pore sizes. In contrast, spinodal decomposition results in a well interconnected, mechanically strong membrane with highly uniform pore sizes. Here I describe recent quantitative studies of the coarsening effects on the microstructure of membranes produced via TIPS process. The dependence of microstructure on coarsening time, quench depth, solution viscosity, and polymer molecular weight was investigated in order to distinguish among three possible coarsening mechanisms, Ostwald ripening, coalescence, and hydrodynamic flow, which may be responsible for structural evolution after the early-stage phase Separation (spinodal decomposition or nucleation & growth).

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.10 no.S_3
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• pp.127-137
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• 2001

The sonochemical Process has been applied as a treatment method and was investigated its effect on the decomposition of humic substances(HS). The reaction kinetics and mechanisms in the Process of sonochemical treatment for humic substances(HS) in wastewater have also been discussed. It was observed that the metal ions such as Fe(II) and Mn(II) showed catalytic effects, while Al(III), Ca(II), and Mg(II) had inhibitory effects on the decomposition of humic substances in sonochemical reaction with hydrogen peroxide. Experimental results also showed factors such as hydrogen peroxide dose affected the formation of disinfection by-products. Two trihalomethanes, chloroform and dichlorobromomethane were formed as major disinfection by-products during chlorination. The mechanism of radical reaction is controlled by an oxidation process. The radicals are so reactive that most of them are consumed by HS radicals and hydroxyl radicals can be acted on organic solutes by hydroxyl addition, hydrogen abstraction, and electron transfer. The depolymerization and the radical reaction of HS radicals appear to occur simultaneously. The final steps of the reaction are the conversion of organic acids to carbon dioxide.

• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.610-612
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• 2003

Octanethiol ($CH_3(CH_2)_7SH$) based self-assembled monolayer on Cu(111) in ultra-high vacuum has been examined using x-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD), intergrated desorption mass spectrometry (IDMS), and contact angle analysis. The results show that the octanethiolate monolayers similar to those on gold are formed on Cu(111). The monolayers are stable up to temperatures of about 480 K. Above 495 K the monolayers decompose via the γ-hydrogen elimination mechanism to yield 1-octene in the gas phase. The thiolate head groups on the copper surface change to Cu₂S following the decomposition of hydrocarbon fragments in the monolayers at about 605 K.

• The Journal of Natural Sciences
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• v.1
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• pp.47-59
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• 1987

The thermal decomposition mechanism of BaTiO($$C_2$$O_4$)_2$ $4H_2$O has been investigated employing TG, DTG, and DTA techniques. The intermediate compounds and the gaseous products of decomposition were examined by IR spectrometer and X-ray analyser. The decomposition proceeds through five steps. The first step which is the dehydration of the tetrahydrate is followed by the decomposition of oxalate groups. During the second decomposition, half a mole of carbon monoxide is evolved. The oxalate groups are completely destroyed in the range $260~460^{\circ}C$, resulting in the formation of a carbonate which retains free carbon dioxide in the matrix . the final decomposition of the carbonate takes place between $650~750^{\circ}C$ and yields $BaTiO_3$.

• YAKHAK HOEJI
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• v.34 no.6
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• pp.415-421
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• 1990

The effects of temperature, pH, light and concentration on the degradation of trimebutine maleate in aqueous solution were investigated on the basis of accelerated stability analysis, and the stabilization of the solution was attempted by addition of several additives. The decomposition of trimebutine maleate in solution followed first-order reaction the was not only accelerated by temperature elevation but also the lower the concentratin the more speeded up the reaction. The decomposition mechanism of trimebtine could be confirmed by hydrolysis of ester bond in the structure. It was assumed trimebutine maleate is so photosensitive that the solution of the drug underwent accelerated decomposition under UV rays. What is more, the degradation of trimebutine solution was supposed to catalyzed by specific acid-base catalysis considered the pH dependence for the hydrolysis of ester, and the solution was most stable over the range of pH 2-2.8 in solution. The additives, citric acid, asparitc acid and glutamic acid, inhibited considerably the decomposition of the drug solution, and these additives might be used as stabilizers in trimebutine maleate solution.

• Applied Chemistry for Engineering
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• v.18 no.2
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• pp.136-141
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• 2007

The decomposition of chlorinated methanes including $CCl_4$, $CCl_3H$, and $CCl_2H_2$ was carried out using a thermal plasma process and the characteristics of the process were investigated. The thermal equilibrium composition was analyzed with temperature by Fcatsage program. The decomposition rates at various process parameters including the concentration of reactants, flow rate of carrier gas, and quenching rate, were evaluated, where sufficiently high conversion over 92% was achieved. The generation of main products was strongly influenced by the reaction atmosphere; carbon, chlorine, and hydrogen chloride at neutral condition; carbon dioxide, chlorine, and hydrogen chloride at oxidative condition. The decomposition mechanism was speculated considering the results from Factsage and the identification of generated radicals and ionic species. The main decomposition pathways were found to be dissociative electron attachment and oxidative by radicals formed in a plasma state.