• Journal of applied mathematics & informatics
• /
• 제27권1_2호
• /
• pp.291-299
• /
• 2009

For $G_{\phi}$-sequences ${\phi}_i$ and ${\kappa}$-functions ${\kappa}_i$(i = 1,2,3) we obtain the most general $H{\ddot{o}}lder$ type inequalities on the functions of $G_{\kappa}G_{\phi}$-bounded variations.

• Journal of applied mathematics & informatics
• /
• 제31권3_4호
• /
• pp.499-511
• /
• 2013

In this article, Adomian decomposition method (ADM), variation iteration method(VIM) and homotopy analysis method (HAM) for solving integro-differential equation with singular kernel have been investigated. Also,we study the existence and uniqueness of solutions and the convergence of present methods. The accuracy of the proposed method are illustrated with solving some numerical examples.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
• /
• pp.1233-1236
• /
• 1996

Attitude Control System for a Hydrofoil type catamaran in wave is designed using a Decentralized Adaptive Control technique which is announced already by authors. This automatic attitude control system is designed for its good seaworthiness and for robustness on the variation of center of gravity. The performance is compared with a PID controller and the results show that the Decentralized Adaptive controller has better stability on the variation of the center of gravity.

• Journal of Advanced Marine Engineering and Technology
• /
• 제22권1호
• /
• pp.28-34
• /
• 1998

This paper introduced the thermal characteristics of Moss Rosenberg Verft spherical tank type LNG Carrier. Especially described the temperature variation during cooling down condition. It is not easy task to calculate the temperature variation because of unsteady state condition. In this paper, computer simulation program is developed by using a Tomas Algorithm on unsteady state condition and compared with calculation results and experimental results on existing LNG Carrier voyage.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2000년도 춘계학술대회논문집
• /
• pp.101-105
• /
• 2000

In cold forging die the shrink fitting is generally used to decrease stress and increase die life. In this paper we have studied about the effect of fitting type, When the die insert is splitted into several pieces the maximum stress could be decreased as much as 50~70% The fitting angle could be selected to minimize the maximum stress and the variation of stress on loading and unloading, . In F, E.M result in case 3。 fitting angle the maximum and variation of stress may be minimized.

• 동력기계공학회지
• /
• 제15권1호
• /
• pp.57-63
• /
• 2011

It is very important to determine link composition of a crane in the basic design of the crane. There are many parameters in the design for the link composition of a double link type level luffing jib crane. We analyze the variation of link composition according to the variation of these parameters which are the angle of fixed link, the angle between the fixed link and backstay when the position of the crane is the maximum working radius, the ratio of fly jib length between two moving hinges to the total length of fly jib, the length of backstay, and the slewing radius. In this paper, we describe the application of the previous analysis program of the link composition design for a double link type level luffing jib crane.

• 한국응용곤충학회지
• /
• 제19권1호
• /
• pp.1-4
• /
• 1980

벼도열병균의 한 균주를 벼에 접종했을때 형성된 이병성병반 및 중도형병반에서 얻어진 단포자분리균주간의 병원성의 양적차이를 온실에서 조사하였다. 단일이병성병반에서 분리된 대부분의 단포자분리균은 단일중도형병반에서 분리한 균주보다 이병성병반형성율이 현저히 높았고 중도형병반 형성은 비슷하였다. 특히 중도형병반에서 분리한 균주가 저항성병반을 더 많이 형성하였다. 이들 두 단포자분리균주내에서도 형성된 병반수에 다소의 변이를 보였다.

• International Journal of Fluid Machinery and Systems
• /
• 제5권1호
• /
• pp.30-37
• /
• 2012

A two dimensional Darrieus-type turbine has been proposed for the hydropower utilization of extra-low head less than 2m. In a practical use of Darrieus-type hydro-turbine, head and flow rate may be varied temporally and seasonally. Considering that the cost advantage is required for the low head hydro turbine system, the Darrieus turbine should be operated with high efficiency in the wider range of flow rate possibly by using an additional device with simpler mechanism. In the present paper, an adjustment of inlet nozzle section by lowering the inlet nozzle height is proposed to obtain the preferable inlet velocity in low flow rate conditions. Effects of resulting spanwise partial inlet flow are investigated. Finally, an effective modification of inlet nozzle height over flow rate variation is shown.

• KSTLE International Journal
• /
• 제10권1_2호
• /
• pp.37-42
• /
• 2009

This paper presents the characteristics of volumetric efficiency of an axial type piston pump considering the piston tilting. A numerical analysis is carried out in order to obtain the pressure distribution considering the fluid inertia at the notch of the valve plate. The cylinder pressure variation and the discharge flow rate are measured experimentally according to the operating conditions such as supply pressure, rotational speed, and viscosity of the working fluid by using the cam type test apparatus. Leakage is also measured considering piston tilting. The characteristics of the volumetric efficiency are analyzed with respect to various operating conditions and leakage is also analyzed according to the piston tilting angle. Results are applicable to improve the design of an axial type piston pump.

• Journal of Welding and Joining
• /
• 제3권1호
• /
• pp.40-45
• /
• 1985

Wire meling characteristics were examined with variation of gas formers such as $MgCO_3, CaCO_3 and Li_ 2CO_ 3$ by self-shielded flux cored arc welding. The flux cored wire of overlap type was welded by DCRP. The results obtainedareas follows. 1) Drop type was observed with no gas former, repelled type with MgCO_3$ added and short circuit type with $Li_2CO_3$ added. The variation of transfer mode was related to the blowing force of $CO_2$ gas and the surface tension of the slag. 2) Droplet size increased with adding gas formers due to the effect of $CO_2$ gas cushion. 3) Core spikes were observed more frequently with increasing the amount of gas formers.