• Proceedings of the KIEE Conference
• /
• 2009.07a
• /
• pp.181_182
• /
• 2009

Some phenomena occurred when one phase of the line circuit breaker was opened while a generator was operating to connect with the power grid were simulated by PSCAD/EMTDC and the analysis for the reason of operation and non-operation of protective relay will contribute to prevent spreading damage when same prospective faults occur.

• Journal of Electrical Engineering and Technology
• /
• v.10 no.2
• /
• pp.676-687
• /
• 2015

Path planning algorithms are used to allow mobile robots to avoid obstacles and find ways from a start point to a target point. The general path planning algorithm focused on constructing of collision free path. However, a high continuous path can make smooth and efficiently movements. To improve the continuity of the path, the searched waypoints are connected by the proposed polynomial interpolation. The existing polynomial interpolation methods connect two points. In this paper, point groups are created with three points. The point groups have each polynomial. Polynomials are made by matching the differential values and simple matrix calculation. Membership functions are used to distribute the weight of each polynomial at overlapped sections. As a result, the path has $G^2$ continuity. In addition, the proposed method can analyze path numerically to obtain curvature and heading angle. Moreover, it does not require complex calculation and databases to save the created path.

• International Journal of Precision Engineering and Manufacturing
• /
• v.3 no.4
• /
• pp.31-36
• /
• 2002

A continuous tool-path, that is to cut continuously with the minimum number of cutter retractions during the cutting operations, is developed in order to minimise the fluctuation of cutting load and the possibility of chipping on the cutting edge in HSM (high-speed machining). This algorithm begins with the offset procedure along the boundary curve of the sculptured surface being machined. In the of offset procedure, the offset distance is determined such that the scallop height maintains a constant roughness to ensure higher levels of efficiency and quality in high-speed machining. Then, the continuous path is generated as a kind of the diagonal curve between the offset curves. This path strategy is able to connect to neighbor paths without cutter retractions. Therefore, the minimum tool retraction tool-path can be generated And, it allows the sculptured surface incorporating both steep and flat areas to be high-speed machined.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.5-8
• /
• 2006

The Alternative energy has lately attracted considerable attention due to the high oil price and environment problem. In this study, pilot test facility for using the geothermal energy source from riverbank filtration was constructed and monitoring devices are installed to estimate the efficiency of this system. Initial installation cost can be saved efficiently by connect ing a heat pump system into the exist ing pumping well in Changwon riverbank filtration site. One set of monitoring results during summer was presented and analyzed.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.265-268
• /
• 2006

Performed fatigue strength analysis for Hub to get the targeted service life of 20 years. ANSYS is used to analysis. The major structure of bearing which connect the hub and blades is modeled using the element of LINK10. To represent the stiffness of LINK10 element, initial strain and diameter of LINK10 element is applied. Prior to calculating the fatigue damages, the influence matrix is extracted from the unit loads. The target service life of 20 years is achieved from the Analysis results.

• 한국신재생에너지학회:학술대회논문집
• /
• 2006.11a
• /
• pp.376-379
• /
• 2006

In this paper, stack voltage monitoring module is developed which monitor cell voltage of the fuel cell stack and transfer it to the main controller for monitoring fault and stopping drive when the trouble is happened in the fuel cell stack. Especially, the circuit, for monitoring each cell voltage of several hundreds cells in stack, is designed and analyzed. The connector is also developed for making wire harness simple and low cost because wire harness is complicated when the cells are connect each monitoring circuit.

• Journal of Chest Surgery
• /
• v.15 no.3
• /
• pp.331-337
• /
• 1982

Complete TGA is a common congenital cardiovacular anomaly, and without palliative or corrective surgery, the infant born with TGA rarely survives the first year of life. Hemodynamically, recirculated blood flow in the systemic and pulmonary circuit has a key role in systemic arterial oxygen saturation and the status of the pulmonary vascular bed. Recently a d-TGA with VSD and PS, in a 12 year old male patient had been tried for inversion of the ventricular flow with Rastelli operation. An intracardiac tunnel was constructed between the VSD and the aortic orifice to connect the ventricle to the aorta. The right ventricle was connected with the pulmonary circulation by anastomosis of an valved conduit between the right ventricle and the distal end of the pulmonary artery. During the postop, period, the irreversible renal failure, accompanied by metabolic acidosis and pulmonary edema, occured under relative stabilized cardiac performance state. The autopsy was done, which revealed diffuse infarcted area in both kidney and preserved intra & extracardiac graft constructed.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 1996.04a
• /
• pp.709-712
• /
• 1996

Generating a project network of a specific construction project is very time consuming and difficult task in the field. To effectiviely automate and support the planning process, we design a case-based project planning expert system inspired by the fact a human expert project planner uses previous cases for planning a new project. A construction project case consist of its specific characteristics and the corresponding project network (i.e. project plan). Using frame based representation. we represent the project features affecting the progress network and the entities composing the project plan such as the buildings, construction methods, WBS (work breakdown structure), activities, and resources. The project planning process runs through most similar case retrieval, case adaptation, and user requirement satisfaction. We represent the construction domain knowledge for each procedure using constraints and rules. We develop the methodology for constraint-based case adaption. Case adaptation process mainly consist of activity generation/deletion and predecence constraint satisfaction, for which we develop the dynamic constraint generation method and connect user-level requirement representation the system-level network modification knowledge. The methodology is being applied to the prototype for apartment construction project planning.

• Proceedings of the Korean Operations and Management Science Society Conference
• /
• 2000.04a
• /
• pp.766-769
• /
• 2000

In recent years, Internet/Intranet represents the next generation of computing environment. Therefore, it is necessary to integrate WWW((World Wide Web) over internet/intranet and DBMS(Database Management System) in proportion to the increase of various users' request and an amount of data variety. Also, also full variety of service over WWW need to accomplish rapidly modification of bug and make a betterment of system according to a feature of rapid change of information and an importance of interaction with users. The typical CGI method commonly used to connect with database has a disadvantage in time and resources in system due to frequent connection with database. Therefore, this paper provides the conceptual structure and implementation of information management system over WWW with applying a recent information technology called ASP(Active Server Pages) that controls and arranges client logic dynamically in server-side and introducing a concept of working group and folder to database design.

• The Journal of Korea Robotics Society
• /
• v.5 no.4
• /
• pp.326-331
• /
• 2010

Marionette controlling robot has a problem that generates interference in rotation and intersection, therefore, the research on the independent shifter to move freely on the stage is required. Connecting omni-directional mobile robot with marionette controlling robot can solve this problem. Omni-directional mobile robot makes itself rotate and translate in 2D plane freely. Magnetic device is used to connect the moving part with the control part of the robot to minimize the intereference generated by the movement of robot. When robot moves, it can move to all directions with the suitalbe setting of banlance power. The moment of inertia is minimized by dividing the robot to the upper and lower parts in the marionette performance stage. Rotation and interference problem of independent omni-wheel Robot can be solved by using the permanent magnet. The efficiency and safety of the marionette controlling robot is proved by the experiment.