• The KIPS Transactions:PartC
• /
• v.18C no.3
• /
• pp.157-166
• /
• 2011

The virtualization layer is executed in higher authority layer than kernel layer and suitable for monitoring operating systems. However, existing virtualization monitoring systems provide simple information about the usage rate of CPU or memory. In this paper, the monitoring system using full virtualization technique is proposed, which can monitor virtual machine's dynamic kernel object as memory, register, GDT, IDT and system call table. To verify the monitoring system, the proposed system was implemented based on KVM(Kernel-based Virtual Machine) with full virtualization that is directly applied to linux kernel without any modification. The proposed system consists of KvmAccess module to access KVM's internal object and API to provide other external modules with monitoring result. In experiments, the CPU utilization for monitoring operations in the proposed monitering system is 0.35% when the system is monitored with 1-second period. The proposed monitoring system has a little performance degradation.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1295-1296
• /
• 2007

A lot of researches about dye-sensitized solar cell (DSC) are recently being conducted. Because DSC has several advantages to pass the limits of silicon solar cells such as a low manufacturing expense, a simple manufacturing process and its transparency. But most researches on DSC are still conducted about the unit cell and laboratory-centered. That is, present researches on DSC are not practical. Therefore, researches about large area cells and modules have to be prerequisites for DSC to have the practicality. Characteristics of large area DSC are so different from those of small area DSC in aspect of fill factor and efficiency. In this study, we made an experiment on finding suitable size of DSC that has the most effective power according to the variation of active area. In detail, the experiment was conducted about the optimum ratio of length to width and we introduced the ratio of active area to non-active area to find the active area which has the best output. Because small DSC doesn‘t have the best output in comparison with total area of cell although the smaller DSC has the better efficiency. As a result, we achieved the optimum ratio of length to width of 8:3 and active area of $8cm^2$ as the optimum size for upscaling DSC.

• Proceedings of the KSR Conference
• /
• 1999.11a
• /
• pp.46-53
• /
• 1999

As of July 1999, i,185 lomocotives(excluding metropolitan area electric locomotives) are in Korean National Railroad(KNR). With this limited number of resources assigning locomotives to each trains of timetable is very important in the entire railway management point of view because schedule can be regarded as goods in transportation industry. On a simple rail network, it is rather easier to assign proper locomotives to trains with the experience of operating experts and get optimal assignment solution. However, as the network is getting bigger and complicated, the number of trains and corresponding locomotives will be dramatically increased to rover all the demands required to service all of the trains in timetable. There will be also numerous operational constraints to be considered. Assigning proper locomotives to trains and building optimal cyclic rotations of locomotive routings will result in increasing efficiency of schedule and giving a guarantee of more profit. The purpose of this study is two fold: (1) we consider a planning-level locomotive scheduling problem with the objective of minimizing the wasting cost under various practical constraints and (2) development of implementation prototype program of its assigning result. Not like other countries, i.e. Canada, Sweden, Korean railroad operates on n daily schedule basis. The objective is to find optimal assignment of locomotives of different types to each trains, which minimize the wasting cost. This problem is defined on a planning stage and therefore, does not consider operational constraints such as maintenance and emergency cases. Due to the large scale of the problem size and complexity, we approach with heuristic methods and column generation to find optimal solution. The locomotive scheduling prototype consists of several modules including database, optimization engine and diagram generator. The optimization engine solves MIP model and provides an optimal locomotive schedule using specified optimization algorithms. A cyclic locomotive route diagram can be generated using this optimal schedule through the diagram generator.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.47 no.4
• /
• pp.289-299
• /
• 2019

Attitude control modeling and simulation (M&S) can be extensively applied in overall development process, from simple algorithm design to on-board software verification. This paper introduces CMG-based attitude control M&S software, which consists of 6-DOF modeling (CMG and space environments modeling), and attitude control algorithm. The M&S software is divided into three modules, from an inner CMG motor control module to an outer earth observation mission module. While an application of this developed software is currently limited to the initial-phase attitude controller development, its application area can be extended to the later-phases by considering sophisticated model information in future.

• Design & Manufacturing
• /
• v.15 no.4
• /
• pp.43-50
• /
• 2021

Pump-cap is a device for discharging the contents stored inside a container to the outside of the container by a simple operation by a certain amount. In particular, in recent years, as the number of cosmetic products made of functional materials has rapidly increased, the development of convenient containers for functional materials is being actively conducted. Among these, there are a growing number of products that show their efficacy only by mixing two components, so the development of a dual pump cap container is necessary. However, the conventional dual pump cap container has a problem in that it is difficult to implement a quantitative discharge as solutions having different viscosities are used. Therefore, in this study, a discharge port of a dual pump cap that can apply an optimal ratio was designed by analyzing the discharge amount of two components with different viscosities through computational fluid dynamics. Since the discharge amount is affected by the size of the discharge port, the higher the viscosity of the solution, the larger the discharge port should be set. Conversely, the lower the viscosity, the smaller the discharge port should be. Through this, it is possible to dispense a fixed amount of a heterogeneous solution by one pumping, and it is determined that the user's convenience will increase.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.22 no.1
• /
• pp.1-6
• /
• 2022

In this paper, the design of lightweight S-Box structure for implementing a low power AES cryptosystem based on composite field. In this approach, the S-Box is designed as a simple structure by which the three modules of x², λ, and GF((2²)²) merge into one module for improving the usable area and processing speed on GF(((2²)²)²). The designed AES S-Box is modelled in Veilog-HDL at structural level, and a logic synthesis is also performed through the use of Xilinx ISE 14.7 tool, where Spartan 3s1500l is used as a target FPGA device. It is shown that the designed S-Box is correctly operated through simulation result, where ModelSim 10.3. is used for performing timing simulation.

• Journal of Korea Multimedia Society
• /
• v.14 no.2
• /
• pp.153-170
• /
• 2011

OMTP (Open Mobile Terminal Platform) is a global forum made by telecommunications providers to promote user-oriented mobile services and data business. Devised by OMTP, BONDI is a browser-based application or a mobile web run-time platform to help widgets make good use of functions of mobile devices in a secure way. BONDI enables applications programmed with web standard technologies such as HTML, JavaScript, CSS, and AJAX to reach the internal functions of mobile devices. Since BONDI, which is not just a simple network application, can reach the internal resources of devices in standard ways, it enables the application and widgets to be developed regardless of tile OS or platform. Web browser-based widgets are vulnerable to the network environment, and their exeeution speed can be slowed as the operations of the widgets or applications become heavy. However, those web widgets will be continuously used thanks to the user-friendly simple interface and the faster speed in using web resources more than the native widgets inside the device. This study suggested a method to effectively operate and manage the resource of OMTP BONDI web widget and then provided an improved result based on a running performance evaluation experiment. The experiment was carried to improve the entire operating time by enhancing the module-loading speed. In this regard, only indispensable modules were allowed to be loaded while the BONDI widget was underway. For the purpose, the widget resource list, able to make the operating speed of the BONDI widget faster, was redefined while a widget cache was employed. In addition, the widget box, a management tool for removed widgets, was devised to store temporarily idle widgets.

• YAKHAK HOEJI
• /
• v.55 no.2
• /
• pp.106-115
• /
• 2011

Systematic toxicological analysis (STA) means the process for general unknown screening of drugs and toxic compounds in biological fluids. In order to establish STA, in previous study we investigated pattern of drugs & poisons in autopsy cases during 2007~2009 in Korea, and finally selected 62 drugs as target drugs for STA. In this study, rapid and simple drug identification and quantitative analytical program by gas chromatography-mass spectrometry(GC-MS) was developed. The in-house program, "DrugMan", consisted of modified chemstation data analysis menu and newly developed macro modules. Total 55 drugs among 62 target drugs were applied to this program, they were 14 antidepressants, 8 anti-histamines, 5 sedatives/hypnotics, 5 narcotic analgesics, 3 antipsychotic drugs, and etc. For calibration curves, fifty five drugs were divided into four groups of range considering their therapeutic or toxic concentrations in blood specimen, i.e. 0.05~1 mg/l, 0.1~1 mg/l, 0.1~5 mg/l or 0.5~10 mg/l. Standards spiked bloods were extracted by solid-phase extraction (SPE) with trimipramine-D3 as internal standard. Parameters such as retention times, 3 mass fragment ions, and calibration curves for each drug were registered to DrugMan. A series of identification, semi quantitation of target drugs and reporting the results were performed automatically. Calibration curves for most drugs were linear with correlation coefficients exceeding 0.98. Sensitivity rate of DrugMan was 0.90 (90%) for 55 drugs at the level of 0.5 mg/l. For standard spiked bloods at the level of 0.5 mg/l for 29 drugs, semi quantitative concentrations were ranged 0.36~0.64 mg/l by DrugMan. If more drugs are registered to database in DrugMan in further study, it will be useful tools for STA in forensic toxicology.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.1
• /
• pp.111-118
• /
• 2023

The purpose of this study is to study jewelry designs presented to general consumers who seek new products and diversity. We would like to present a modular jewelry design with a structure and combination method that is distinct from jewelry in a multimodal replacement method that allows various product modules sold in the past to be worn interchangeably. Problems are likely to occur when a number of existing rather small parts are manufactured in a complex combination method, and difficulties may follow when consumers replace decorative parts and lose them in the process of assembling small fixture parts. Therefore, in order to reduce these problems, we try to make it different from jewelry products made with a simple and simple design so that it can be easily replaced and worn without the need for other coupling parts, and produced using the latest 3D printer (Rapid Prototyping). In this study, based on the experience and know-how gained while engaging in field work, it was possible to make a real object and focused on minimizing problems during the production process, and through this, time and economic loss can be reduced. The purpose of the study is to produce improved jewelry products by expressing more sophisticated and differentiated shapes by using 3D programs (CAD).

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.35D no.9
• /
• pp.26-34
• /
• 1998

This paper presents a characterization method for faults of circuit patterns on MCM(Multichip Module) or PCB(Printed Circuit Board) substrates with electron beams of a SEM(Scanning Electron Microscope) by inducing voltage contrast on the signal line. The experimentation employes dual potential electron beams for the fault characterization of circuit patterns with a commercial SEM without modifying its structure. The testing procedure utilizes only one electron gun for the generation of dual potential electron beams by two different accelerating voltages, one for charging electron beam which introduces the yield of secondary electron $\delta$ < 1 and the other for reading beam which introduces $\delta$ > 1. Reading beam can read open's/short's of a specific net among many test nets, simultaneously discharging during the reading process for the next step, by removing its voltage contrast. The experimental results of testing the copper signal lines on glass-epoxy substrates showed that the state of open's/short's had generated the brightness contrast due to the voltage contrast on the surface of copper conductor line, when the net had charged with charging electron beams of 7KV accelerating voltages and then read with scanning reading electron beams of 2KV accelerating voltages in 10 seconds. The experimental results with Au pads of a IC die and Au plated Cu pads of BGA substrates provided the simple test method of circuit lines with 7KV charging electron beam and 2KV reading beam. Thus the characterization method showed that we can test open and short circuits of the net nondestructively by using dual potential electron beams with one SEM gun.