• Journal of Information Technology Applications and Management
• /
• 제19권1호
• /
• pp.37-46
• /
• 2012

The scheduling problem of large products like ships, airplanes, space shuttles, assembled constructions, and automobiles is very complex in nature. To reduce inherent computational complexity, we often design scheduling systems that the original problem is decomposed into small sub-problems, which are scheduled independently and integrated into the original one. Moreover, the steep growth of communication technology and logistics makes it possible to produce a lot of multi-nation corporation by which products are produced across more than one plant. Therefore vertical and lateral coordination among decomposed scheduling systems is necessary. In this research, we suggest an agent-based coordinating mechanism for multi-level scheduling systems in supply chain. For design of a general coordination mechanism, at first, we propose a grammar to define individual scheduling agents which are responsible to their own plants, and a meta-level coordination agent which is engaged to supervise individual scheduling agents. Second, we suggest scheduling agent communication protocols for each scheduling agent topology which is classified according to the system architecture, existence of coordinator, and direction of coordination. We also suggest a scheduling agent communication language which consists of three layers : Agent Communication Layer, Scheduling Coordination Layer, Industry-specific Layer. Finally, in order to improve the efficiency of communication among scheduling agents we suggest a rough capacity coordination model which supports to monitor participating agents and analyze the status of them. With this coordination mechanism, we can easily model coordination processes of multiple scheduling systems. In the future, we will apply this mechanism to shipbuilding domain and develop a prototype system which consists of a dock-scheduling agent, four assembly-plant-scheduling agents, and a meta-level coordination agent. A series of experiment using the real-world data will be performed to examine this mechanism.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2004년도 ICCAS
• /
• pp.546-551
• /
• 2004

In this paper, a level controller is designed with the neuro-fuzzy model based on Takagi-Sugeno fuzzy system. The fuzzy system is employed as the controller, which can be tuned by the neural network mechanism based on a gradient descent technique. The tuning mechanism will provide an optimal process input by forcing the process error to zero. The proposed controller provides the online tunable mode to adjust the consequent membership function parameters. The controller is implemented with M-file and graphic user interface (GUI) of Matlab program. The program uses MPIBM3 interface card to connect with the industrial processes In the experimentation, the proposed method is tested to vary of the process parameters, set points and load disturbance. Processes of one tank and two tanks are used to evaluate the efficiency of our controller. The results of the both processes are compared with two PID systems that are 3G25A-PIDO1-E and E5AK of OMRON. From the comparison results, our controller performance can be archived in the case of more robustness than the two PID systems.

• 한국산학기술학회논문지
• /
• 제12권5호
• /
• pp.2322-2326
• /
• 2011

기존 암호시스템은 비도를 증가시키기 위하여 데이터와 키 값을 별도로 사용하고 일정 횟수의 반복성을 수행하며 무한수열에 가까운 LFSR의 주기특성을 증가시키므로 암호시스템의 효율이 저하되는 문제점이 있다. 본 논문에서 제안된 알고리즘은 대칭형 암호방식에 비대칭형 암호개념을 적용한 새로운 기능의 데이터 재배열, 치환, 데이터 암호블록, 키 스케쥴러로 구성하였다. 본 논문에서 제안된 암호알고리즘은 범용 SYNOPSYS를 이용하여 스마트 카드의 암호시스템을 설계하였고 40MHz의 시스템 속도로 ALTERA MAX+PlUS II 툴의 모의실험한 결과 단일 라운드로 16 라운드의 비도와 640Mbps의 데이터 처리율로 AES보다 52% 향상됨 확인하였다.

• 한국생산제조학회지
• /
• 제22권3_1spc호
• /
• pp.504-508
• /
• 2013

This paper describes in detail the life prediction models and simulations of thermal fatigue under different mold compounds and chip sizes for wafer-level embedded SiP. Three-dimensional finite element models are built to simulate the viscoplastic behaviors for various mold compounds and chip sizes. In particular, the bonding parts between a mold and silicon nitride (Si3N4) are carefully modeled, and the strain distributions are studied. Three different chip sizes are used, and the effects of the mold compounds are observed. Through the numerical studies, it is found that type-C, which has a relatively lower Young's modulus and higher CTE, has a better fatigue life than the other mold compounds. In addition, the $4{\times}4$ chip has a shorter life than the $6{\times}6$ and $8{\times}8$ chips.

• 인터넷정보학회논문지
• /
• 제6권2호
• /
• pp.85-97
• /
• 2005

1985년에 처음 등장했던 테트리스는 많은 시간이 지난 지금에도 많은 유저들에게 사랑 받는 게임이 되었다. 지금까지의 테트리스는 줄이 삭제 될 때마다 삭제된 줄의 수에 따라 점수를 주는 방식을 채용하였고, 연속 공격 등에 관해 가산점을 부여해주었다. 그러나 이러한 점수 산출방식은 너무 일정하고 단순한 패턴을 주었다. 본 논문에서는 기존의 점수 계산 방식과는 다른 단계별 점수 계산 방식을 통하여 새로운 테트리스 게임 시스템을 설계 및 구현하고자 한다. 즉, 이는 전에 삭제된 줄의 수와 현재 삭제된 줄의 수를 비교하여 기본 점수에 가산점을 부여하는 방식이다. 단계별 점수산출방식을 이용하여 기존의 테트리스에서 한층 더 진보된 테트리스의 전략적인 이용을 가능하게 해 줄 것이다.

• 한국철도학회:학술대회논문집
• /
• 한국철도학회 2005년도 추계학술대회 논문집
• /
• pp.223-228
• /
• 2005

Precast concrete deck has many advantages comparing with the in-situ concrete deck, and has been successfully applied to replacement of the deteriorated decks and to the newly constructed highway bridges in domestic region. In order to apply the precast decks into the railway bridges, however, differences of the load characteristics between the highway and the railway should be properly taken into account including the train load, longitudinal force of the continuous welded rail. acceleration or braking force, temperature change and shrinkage. Proper level of the longitudinal prestress of the tendons that can ensure integrity of the transverse joints in the deck system is of a primary importance. To this aim, the longitudinal tensile stresses induced by the design loads are derived using three-dimensional finite element analyses, design codes and theoretical equations for the frequently adopted PSC composite girder railway bridge. The estimated proper prestress level to counteract those tensile stresses is over 2.4 MPa, which is similar to the case of the highway bridges.

• 한국군사과학기술학회지
• /
• 제23권6호
• /
• pp.639-649
• /
• 2020

Air data systems measure airspeed, pressure altitude, angle of attack and angle of sideslip. These measurements are essential for operating flight control laws to ensure safe flights. Since the loss or corruption of air data measurements is considered as catastrophic, a high level of operational reliability needs to be achieved for air data systems. In the case of unmanned air vehicles, failure of any of air data sensors is more critical due to the absence of onboard pilot decision aid. This paper presents design of a dual redundancy air data system and the integration process for an unmanned air vehicle. The proposed dual-redundant architecture is based on two independent air data probes and redundancy management by central processing in two independent flight control computers. Starting from unit testing of single air data sensor, details are provided of system level tests used to meet overall requirements. Test results from system integration demonstrate the efficiency of the proposed process.

• 대한기계학회논문집
• /
• 제17권6호
• /
• pp.1412-1422
• /
• 1993

본 연구는 각주형 금형부품을 절삭가공할때 부품의 설계데이터로부터 부품의 형상적인 특징을 추출하여 공정설계시스템인 MOLDCAPP과 작업설계시스템인 COPS에서 사용할 수 있는 정보를 생성함으로써 CAD/CAM의 연결을 자동화할 수 있는 특징형상 인식 시스템을 개발하는 연구로, 특징형상 인식기법의 창안보다는, 가용한 기술의 장 점을 사용하여 각주형 공작물의 기계 절삭가공으로 생성될 수 있는 형상을 특징형상으 로 정의하고 ACIS로 설계된 CAD데이터로부터 정의된 특징형상을 추출하여 각 특징형상 들의 형상 데이터를 결정함으로써 MOLDCAPP, COPS 등의 공절설계시스템의 입력데이터 를 생성할 수 있도록 Fig.1과 같이 설계하였다. 특히 PART시스템과 같이 인식대상이 포괄적이지 않으나, 금형부품상의 특징형상으로 범위를 축소하고 금형부품의 가공특징 을 고려하여 인식규칙을 단순화함으로써 금형가공공정의 CAD/CAM연결에 이용될 수 있도록 하였다.

• 대한한방내과학회지
• /
• 제22권2호
• /
• pp.223-237
• /
• 2001

Objective : There have not been studies on the oriental medicine research trends and qualitative analysis of Korean oriental medicine articles in Korea, particularly in the oriental medicine area. This study's purpose is to appreciate Korean oriental medicine's research trends and assess the quality of the Korean oriental medical journals' level. This study will help upgrade Korean oriental medical journals. Method : We found 93 stroke-related articles in the Journal of Korean Oriental Medicine, published between 1980(Volume 1) and 2001(Volume 45). We surveyed the institutes involved in each study, and the number of people in each study. We seperated by epidemiological study design, the studies into categories. Campbell and Stanley's study design into 6 categories, statistical methods into 13 categories. Next, we assessed the 41 articles by a checklist, which had 10 categories. The quality score was analyzed by survey variables over the period, which were divided by the date of publication: the 1980s, the first half of the 1990s, second half of the 1990s and 2000s. Results : 46.3% od the studies didn't use statistical methods. 56.1%, were case series studies by classification of epidemiological study design, and 53.6% were one-shot case studies designed by Campbell and Stanley's study design. The quality score was 58.33 point 60 is average. In quality level by Browman GP etc.'s, 83.0% of the studies were included in V levels. But, the quality scores were significant by presence of reviewer system, statistical method's usage, and over the period. Conclusion : The Journal of Korean Oriental Medicine needs to improve the quality its articles. To improve the quality of oriental medicine related articles, the following are necessary: working together, joint work of inter-educational system, strengthening of reviewer system, use of statistical methods, and consulting to the expert of research at the stage of study design.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2001년도 춘계학술대회 논문집
• /
• pp.71-76
• /
• 2001

This paper describes a research work of developing system for conceptual die design system for Fine blanking. The method of approaching to the system is based on the knowledge-based rules. Knowledge for the system is formulated from experimental results and the empirical knowledge of field experts. This system has been written in VisualLISP on the AutoCAD using a personal computer and in Microsoft Visual Basic ver.6.0. Transference of data is accomplished by DXF (Drawing Exchange Format) method. This system consists of six modules, which are cognition of a drawing, cognition of shear length, calculation of shear force, materials properties database, determination of degree of difficulty of the product, determination of approximate life of punch and die modules. Results carried out in each module will provide efficiency to the designer and the manufacturer of die for Fine blanking. But the main focus of this system is the design of die for Fine blanking in the level of general concept. In order to use powerful tool in this field, developed system will be studied continuously.