• 제어로봇시스템학회:학술대회논문집
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• 1998.10a
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• pp.14-19
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• 1998

In this paper, a target approachable force-guided control with adaptive accommodation for the complex assembly is presented. The complex assembly (CA) is defined as a task which deals with complex shaped parts including concavity or whose environment is so complex that unexpected contacts occur frequently during insertion. CA tasks are encountered frequently in the field of the manufacturing automation and various robot applications. To make CA successful, both the bounded wrench condition and the target approachability condition should be satisfied simultaneously during insertion. By applying the convex optimization technique, an optimum target approaching twist can be determined at each instantaneous contact state as a global minimum solution. Incorporated with an admissible perturbation method, a new CA algorithm using only the sensed resultant wrench and the target twist is developed without motion planning nor contact analysis which requires the geometry of the part and the environment. Finally, a VME-bus based real-time control system is built to experiment various CA task. T-insertion task as a planar CA and double-peg assembly task as a spacial assembly were successfully executed by implementing the new force-guided control with adaptive accommodation.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.643-649
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• 2016

When a cyclotron produces $^{18}F^-$, accelerated protons interact with metal parts of the cyclotron machine and induces radioactivity. Especially, the target window and chamber of the target assembly are the main parts where long-lived radionuclides are generated as they are incident by direct beams. It is of great importance to identify radionuclides induced in the target assembly for the safe operation and maintenance of a cyclotron facility. In this study, we analyzed major radionuclides generated in the target assembly by an operation of the Cyclotron 18/9 machine and measured dose rates after the operation to establish the radiation safety guideline for operators and maintenance personnel of the machine. Gamma spectroscopy with HPGe was performed on samples from the target chamber and Havar foil target window to identify the radionuclides generated during the operation for production of $^{18}F^-$- isotope and their specific activity. Also, the dose rates from the target were measured as a function of time after an operation. These data will help improve radiological safety of operating the cyclotron facilities.

• Journal of Microbiology and Biotechnology
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• v.29 no.1
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• pp.1-10
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• 2019

Gram-negative pathogens, such as Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, pose a serious threat to public health worldwide, due to high rates of antibiotic resistance and the lack of development of novel antimicrobial agents targeting Gram-negative bacteria. The outer membrane (OM) of Gram-negative bacteria is a unique architecture that acts as a potent permeability barrier against toxic molecules, such as antibiotics. The OM is composed of phospholipids, lipopolysaccharide (LPS), outer membrane ${\beta}-barrel$ proteins (OMP), and lipoproteins. These components are synthesized in the cytoplasm or in the inner membrane, and are then selectively transported to the OM by the specific transport machines, including the Lol, BAM, and Lpt pathways. In this review, we summarize recent studies on the assembly systems of OM components and analyze studies for the development of inhibitors that target these systems. These analyses show that OM assembly machines have the potential to be a novel attractive drug target of Gram-negative bacteria.

• Applied Science and Convergence Technology
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• v.24 no.5
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• pp.125-131
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• 2015

We investigated the thermal characteristics of rotating anode X-ray tube to develop it for digital radiography by using computer simulation. The target which is the area of the anode struck by electrons is the most important component to get a long life of X-ray tube. So we analyze the thermal characteristics of the target and rotor assembly according to their emissivity by using ANSYS transient thermal simulation and then compare with the measured data of the target temperature operating in aging process of X-ray tube. Especially, keeping the lead coated layer as the role of metal lubricant on ball bearing enables to prevent the noise in rotating anode. The simulation result showed that its temperature was under the melting point of the lead in X-ray tube for digital radiography with 1.2 mm large focal spot 0.6 mm small focal spot and 150 kV tube voltage. We also investigated the relationship between the diameter of the anode shaft and the temperature of the anode and rotor assembly. It has been confirmed that the smaller anode shaft could be good for the rotor thermal characteristics.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.3
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• pp.229-236
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• 2020

A crush switch assembly(CSA) connected to an impact fuze provides electrical signal for detonation of the loaded main charge when an impact with the target is detected. Because the CSA experiences continuous changes in flight environment such as changes in velocity, vibration, and stresses, it is necessary to accurately predict the behavior of the fuze to maintain functionality during flight and to detonate when necessary. In this paper, random vibration analysis for flight environment and impact analysis on target hit are performed using FEA. Then, high speed impact tests are performed with the original and scaled down models to ensure operation validation of the manufactured products. The test results are then compared with M&S results to verify the capability of currently modeled CSA.

• The Journal of Bigdata
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• v.7 no.1
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• pp.99-111
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• 2022

A simulation technique can be used to analyze performance measures and support decision makings in manufacturing systems considering operational uncertainty and complexity. The simulation requires an input modeling procedure to reflect the target system's characteristics. However, data collection to build a simulation is quite limited when a target system includes manual productions with a lot of operational time such as construction equipment assembly lines. This study proposes a procedure for simulation input modeling using video data when it is difficult to collect enough input data to fit a probability distribution. We conducted a video-data analysis and specify input distributions for the simulation. Based on the proposed procedure, simulation experiments were conducted to evaluate key performance measures of the target system. We also expect that the proposed procedure may help simulation-based decision makings when obtaining input data for a simulation modeling is quite challenging.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.228-237
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• 1996

On the basis of a brief introduction of the mechanized dry farming in Heilongjiang Province, the author states the developing process from the combination of single technics of farm machinery and agronomy to the technical assembly of high yield cultivation technics and its mathematical expression. According to the main temperature accumulated zones, 5 typical comprehensive technical assembly models for the mechanized cultivation technics and their agricultural machinery systems have been listed. They are, the Heihe " 261" wheat and soybean model : the Yi'an big ridge double row film mulching corn model : the Yongchang high yield mechanized soybean and other grain crops six year rotation model for Keshan state farms. The author conclude that the application of mechanized high yield cultivation technical assembly is the key point to transform the Heilongjiang province from big agriculture to strong agriculture, we have to take " high yield , high quality , high efficiency , s stain -ability and earning foreign currency" as the general target and carry out the corresponding policy and measures for the further development of agricuture.

• Nuclear Engineering and Technology
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• v.45 no.1
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• pp.81-88
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• 2013

Neutron spectrum analyses of spallation neutrons are conducted in the accelerator-driven system (ADS) facility at the Kyoto University Critical Assembly (KUCA). High-energy protons (100 MeV) obtained from the fixed field alternating gradient accelerator are injected onto a tungsten target, whereby the spallation neutrons are generated. For neutronic characteristics of spallation neutrons, the reaction rates and the continuous energy distribution of spallation neutrons are measured by the foil activation method and by an organic liquid scintillator, respectively. Numerical calculations are executed by MCNPX with JENDL/HE-2007 and ENDF/B-VI libraries to evaluate the reaction rates of activation foils (bismuth and indium) set at the target and the continuous energy distribution of spallation neutrons set in front of the target. For the reaction rates by the foil activation method, the C/E values between the experiments and the calculations are found around a relative difference of 10%, except for some reactions. For continuous energy distribution by the organic liquid scintillator, the spallation neutrons are observed up to 45 MeV. From these results, the neutron spectrum information on the spallation neutrons generated at the target are attained successfully in injecting 100 MeV protons onto the tungsten target.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.2
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• pp.104-110
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• 2006

When a new facility such as automobile assembly line is designed, computer simulation is often used to estimate its actual throughput level. If it falls short of the target throughput level, then the design must be modified to increase the throughput capacity. For complex facilities having parallel processes and network of material flows, the modification procedure is not trivial. Even if the capacity of a particular bottleneck process is increased, the target throughput may not be achieved because the bottleneck may move to another process. Furthermore, each process has a different set of options with different cost to increase the capacity. In this study, we present a systematic procedure of determining the cost-effective set of options which achieves the target throughput.

• Journal of Korean Society for Quality Management
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• v.41 no.3
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• pp.413-421
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• 2013

Purpose: System availability and life cycle cost are often used to evaluate the system performance and is influenced by the operation and maintenance characteristic. In this paper, we propose the method to improve life cycle cost and satisfy the target availability through redundancy allocation. Methods: We consider the redundancy is available at all items in multi level system. Thus, we assume that sub-assembly, module, components can be duplicated. Simulation and genetic algorithm are employed to optimize redundancy allocation. Results: Target availability is higher, the life cycle cost is increased. In addition, the items for redundancy are selected at higher level in multi level system if target availability is higher. Conclusion: We could know that target availability affects the duplication number of items and the selection of redundancy items. For further study, we will consider new optimization algorithms to compare with the proposed GA algorithm and improve optimization performance.