• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.4
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• pp.81-87
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• 2008

In this study, concerns the crashworthiness of the widely used vehicle structure, square thin-walled tubes, which are excellent on the point of the energy absorbing capacity. An experimental investigation was carried out to study the energy absorption characteristics of thin-walled square tubes subjected to dynamic crushing by axial loading to develop the optimum structural members. The impact velocity was tested in the rage $4.698{\sim}8.2m/s$. To efficiently review the collapse characteristics of these sections, the simulation have been carried out using explicit FEM package, LS-DYNA. The solutions compared with results the impact collapse experiment. Here, the controller are introduced to improve and control the absorbed energy of thin-walled square tubes in this paper. To predict and control the energy absorption, we designed it in consideration to the it's influence, height, thickness, wide ratio in this study. When the controller used, the experimental results of crushing of square tubes controlled by the controller's elements showed a good candidate for a controllable energy absorption capability in impact axial crushing.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.45 no.8
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• pp.639-646
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• 2017

In this paper, a new load monitoring system for military aircraft is introduced. This system consists of sensors, an onboard device and an ground analysis equipment. The sensors and onboard device are mounted on the aircraft and the ground analysis equipment is operated on the ground. Through this system, structural static load can be estimated with flight parameters and structural responses can be measured by sensors due to static load, dynamic load and unexpected events. Especially, optical fiber sensors with mutiplexing capability are utilized. The onboard device was specially designed for complying the requirements of relevant military specifications and was verified through a series of the environment tests. This system was used and evaluated through ground structural tests before flight tests. In the near future, this system will be applied to military aircraft as a structural load monitoring system after flight test evaluation.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7757-7759
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• 2013

Physicians, in order to study the causes of cancer, detect cancer earlier, prevent or determine the effectiveness of treatment, and specify the reasons for the treatment ineffectiveness, need to access accurate, comprehensive, and timely cancer data. The cancer care environment has become more complex because of the need for coordination and communication among health care professionals with different skills in a variety of roles and the existence of large amounts of data with various formats. The goals of health care systems in such a complex environment are correct health data management, providing appropriate information needs of users to enhance the integrity and quality of health care, timely access to accurate information and reducing medical errors. These roles in new systems with use of agents efficiently perform well. Because of the potential capability of agent systems to solve complex and dynamic health problems, health care system, in order to gain full advantage of E- health, steps must be taken to make use of this technology. Multi-agent systems have effective roles in health service quality improvement especially in telemedicine, emergency situations and management of chronic diseases such as cancer. In the design and implementation of agent based systems, planning items such as information confidentiality and privacy, architecture, communication standards, ethical and legal aspects, identification opportunities and barriers should be considered. It should be noted that usage of agent systems only with a technical view is associated with many problems such as lack of user acceptance. The aim of this commentary is to survey applications, opportunities and barriers of this new artificial intelligence tool for cancer care information as an approach to improve cancer care management.

• Korean Journal of Materials Research
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• v.26 no.9
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• pp.486-492
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• 2016

Tungsten (W) thin film was deposited at $400^{\circ}C$ using pulsed chemical vapor deposition (pulsed CVD); film was then evaluated as a nucleation layer for W-plug deposition at the contact, with an ultrahigh aspect ratio of about 14~15 (top opening diameter: 240~250 nm, bottom diameter: 98~100 nm) for dynamic random access memory. The deposition stage of pulsed CVD has four steps resulting in one deposition cycle: (1) Reaction of $WF_6$ with $SiH_4$. (2) Inert gas purge. (3) $SiH_4$ exposure without $WF_6$ supply. (4) Inert gas purge while conventional CVD consists of the continuous reaction of $WF_6$ and $SiH_4$. The pulsed CVD-W film showed better conformality at contacts compared to that of conventional CVD-W nucleation layer. It was found that resistivities of films deposited by pulsed CVD were closely related with the phases formed and with the microstructure, as characterized by the grain size. A lower contact resistance was obtained by using pulsed CVD-W film as a nucleation layer compared to that of the conventional CVD-W nucleation layer, even though the former has a higher resistivity (${\sim}100{\mu}{\Omega}-cm$) than that of the latter (${\sim}25{\mu}{\Omega}-cm$). The plan-view scanning electron microscopy images after focused ion beam milling showed that the lower contact resistance of the pulsed CVD-W based W-plug fill scheme was mainly due to its better plug filling capability.

• Proceedings of the KOR-KST Conference
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• 1995.05a
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• pp.239-250
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• 1995

With speeding up the process of being international municipality, the gravity of lacking parking lots in Shanghai urban area, which directly blocks the traffic in the city, has been revealed. This thesis analyses present automobiles parking capability and forecasts the future's needs for the city. To solve the problem, the concept could be to expand parking areas in city center recently to relax the tention and to do thoughtful planning in the near future on the foundation of fully consideration the trend. The municipal government has to set up policy properly, amplify regulations, strenthern the administration and open up a path to raise founds. Berween road system administration which is dynamic and parking lot system administration which is static, there are a knot on macroscopic meaning and an interference as well. The coordination of these two systems would be reflested on the effects of whole municipal traffic adminisration. Basically, public parking lots are city's foundal facilities, just like roads, bridges, etc. The main problems now in Shanghai are large parking space demands, insufficient facilities, cheap parking expenses comparing with the cost of parking lots construcion and poor administration. According to the forecast on social economy development, there will be 580 thousand automobiles in Shanghai by the year 2000, and the amount of private cars will increase greatly. The frequency of automobiles going out will be 1.45 million per day. Public parking lots being able to afford 105 thousand units are needed. To satisfy the demands, the recent aim of planning should be speed up the parking lots construction, the planning objective in next period should be developing reasonably and exceed the demands properly. In order to realize the planning objective, the government has to formulate correct policy and amplify administration regulations. The government has to adopt both administration and economy means, including charging parking people reasonably, collect necessary taxes, bringing the parking lots planning into general municipality planning, opening up an effective path to raise founds, such as set up founds for parking lots construction, issue bonds and stocks, get loans at home and abroad, etc.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.12
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• pp.1166-1173
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• 2011

Electro-Mechanical Ignition Safety Device(EMISD) for solid rocket motor is designed and manufactured. The EMISD utilizes a true rotary solenoid for arming mechanism and an electric squib(initiator) for generating ignition energy. In order to prove the ignition capability of the EMISD, 10-cc Closed Bomb Test(CBT) is performed, which measures the pressure built by high temperature and high pressure gas generated by operating EMISD. The pressure built in the free volume of 10-cc closed bomb and the opening time of the ignition gas outlet are calculated using one dimensional gas dynamic model which is composed of the ideal gas equation and mass-energy conservation equation. Comparing the test result with model prediction, it is realized that the pressure built in the free volume of closed bomb due to the firing of EMISD, has the efficiency ratio of about 34%.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.2
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• pp.190-197
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• 2011

In industrial distributed control systems, sensors collect data from the physical environment periodically and transmit them to the actuators, which process the control operations based on the received data. For the effective operation of the control systems, the data transmitted by the sensors has to be delivered to the actuators reliably within the deadline, and if the message reception rate of the actuators becomes lower than a threshold, then the performance of the control systems drops greatly. This paper suggests a message routing protocol to transmit periodic messages reliably in a distributed control system based on wireless sensor networks. For reliable message transmission, the proposed protocol selects a routing path whose end-to-end message reception rate is the highest before transmitting data messages. The proposed protocol has the capability of maintaining a target message reception rate for each flow. To maintain the required target reception rate, each destination monitors the actual message reception rate periodically and transmits a feedback message to the source if it drops below the target reception rate. On receiving the feedback message, the source tries to find a new path which can satisfy the target rate. The performance of the proposed protocol has been evaluated using simulation and compared with other protocols in terms of the message reception rate, the message delay and delay jitter, and so on. The simulation results show that the proposed protocol has a higher message reception rate and comparable message delay and delay jitter to other protocols. The simulation results also show that the proposed protocol has an ability to adapt well to the dynamic network traffic change.

• The Journal of Society for e-Business Studies
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• v.12 no.1
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• pp.151-166
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• 2007

As the number of users who are involved in a business process increases, it becomes imperative to effectively control their privileges of accessing sensitive data and information which are usually easily obtained by BPM system. Traditional RBAC (Role-based Access Control) model was first introduced to provide a logical framework to prevent unauthorized users from obtaining confidential, but in more dynamic environment such as B2B and SCM process, it usually lacks in capability of addressing such issues as configurability, customizability, or scalability of user privileges. In this study, we have proposed a privilege-template based RBAC model that can address such issues effectively. We also provided a design of the RBAC model along with illustrative examples and pseudo codes that can be used for implementing a prototype system.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.173-179
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• 2014

In this paper, a motor parameter identification system has been implemented to improve the performance of the position sensorless stroke controller for linear compressors. In order to control the cooling capability of a refrigerator or an air conditioner in which linear compressors are applied, the piston speed should be controlled. The piston speed control can be obtained by adjusting the frequency or the stroke of linear motors. The dynamic performance of linear compressors depends on how accurately the stroke or the piston amplitude is estimated. The merits and demerits of Constant method and PIM (Parameter Identification Method) concerning the needed memory space and the stroke error are discussed and verified via some experimental studies.

• Journal of the Ergonomics Society of Korea
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• v.17 no.3
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• pp.23-39
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• 1998

Several recent aircraft accidents occurred due to goal conflicts between human and machine actors. To facilitate the management of the cockpit activities considering these observations. a computational aid. the Agenda Manager (AM) has been developed for use in simulated cockpit environments. It is important to know pilot intentions performing cockpit operations accurately to improve AM performance. Without accurate knowledge of pilot goals or intentions, the information from AM may lead to the wrong direction to the pilot who is using the information. To provide a reliable flight simulation environment regarding goal conflicts. a pilot goal communication method (GCM) was developed to facilitate accurate recognition of pilot goals. Embedded within AM, the GCM was used to recognize pilot goals and to declare them to the AM. Two approaches to the recognition of pilots goals were considered: (1) The use of an Automatic Speech Recognition (ASR) system to recognize overtly or explicitly declared pilot goals. and (2) inference of covertly or implicitly declared pilot goals via the use of an intent inferencing mechanism. The integrated mode of these two methods could overcome the covert goal mis-understanding by use of overt GCM. And also could it overcome workload concern with overt mode by the use of covert GCM. Through simulated flight environment experimentation with real pilot subjects, the proposed GCM has demonstrated its capability to recognize pilot intentions with a certain degree of accuracy and to handle incorrectly declared goals. and was validated in terms of subjective workload and pilot flight control performance. The GCM communicating pilot goals were implemented within the AM to provide a rich environment for the study of human-machine interactions in the supervisory control of complex dynamic systems.