• Proceedings of the KIEE Conference
• /
• 2002.07c
• /
• pp.1717-1720
• /
• 2002

Electrodeless discharge lamps have been objects of interest and research for several decades, mainly because of their potential for extremely long life, high lamp efficacies and smaller than standard fluorescent lamps size. A series of measurements and observations concerning variables has yielded optical and electrical characteristics for electrodeless discharge lamp like incandescent lamp and circular lamp feature. Last experiment were carried out to determine the lamp temperature at several surface points during operation. Light output levels in excess over 60,000 cd/$m^2$ have been measured in electrodeless discharge lamp for a general of conditions. At lamp surface temperatures have been measured over $80^{\circ}C$, and starting current have been measured over ${\sim}A$.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.214-214
• /
• 2000

This paper deals with the non contact optical sensor to measure the shape of transparent plates such as glass panel of LCD(Liquid Crystal Display). The conventional methods to obtain the shape or thickness of a transparent plates are contact type sensor such as LVOT(Linear Variable Differential Transformer). Due to the contact between the tip of the sensor and the surface of objects, the tip is abraded. In addition, the high temperature glass casting makes the size of sensor body changed. These reasons makes the sensor degraded. In this paper, to overcome these problem, we proposed a low cost noncontact optical sensor this is composed of the Hologram laser unit of a CD-Pickup and a plastic lens. To evaluate the performance of the proposed optical sensor, a series of experiments were performed for various measurement condition. Based upon observation of the experimental result, the developed sensor shows good result for measuring the shape of transparent plates.

• Communications for Statistical Applications and Methods
• /
• v.16 no.6
• /
• pp.1055-1066
• /
• 2009

Many articles have considered a hybrid censoring scheme, which is a mixture of Type-I and Type-II censoring schemes. We introduce a double hybrid censoring scheme and derive some approximate maximum likelihood estimators(AMLEs) of the scale parameter for the half logistic distribution under the proposed double hybrid censored samples. The scale parameter is estimated by approximate maximum likelihood estimation method using two different Taylor series expansion types. We also obtain the maximum likelihood estimator(MLE) and the least square estimator(LSE) of the scale parameter under the proposed double hybrid censored samples. We compare the proposed estimators in the sense of the mean squared error. The simulation procedure is repeated 10,000 times for the sample size n = 20(10)40 and various censored samples. The performances of the AMLEs and MLE are very similar in all aspects but the MLE and LSE have not a closed-form expression, some numerical method must be employed.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1999.11a
• /
• pp.167-173
• /
• 1999

This paper suggests a method to design the deep groove ball bearing for high-load capacity by using a genetic algorithm. The design problem of ball bearings is a typical discrete/continuous optimization problem because the deep groove ball bearing has discrete variables, such as ball size and number of balls. Thus, a genetic algorithm is employed to find the optimum values from a set of discrete design variables. The ranking process is proposed to effectively deal with the constraints in genetic algorithm. Results obtained fer several 63 series deep groove ball bearings demonstrated the effectiveness of the proposed design methodology by showing that the average basic dynamic capacities of optimally designed bearings increase about 9~34% compared with the standard ones.

• 한국해양학회지
• /
• v.18 no.1
• /
• pp.21-28
• /
• 1983

A series of experiments was performed to increase and make our puantitive understanding of the entrainuent and settling processes of fine-grained sediments, which are of critical importance to construct a predictive model of sediment experiments were performed in an annular flume. A rotating top produced a turbulent flow which in turn exerted and are shown to be dependent on the sediment concentration and the presence of clay minerals. The parameters on which entrainment strongly depends were identified to be the shear stress, water content (time ofter deposition), and the type of sediment (grain size and mineralogy).

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2000.10a
• /
• pp.38-44
• /
• 2000

An oil hydraulic line is modeled in which a pipe or two pipes of different size connected in series and terminated in a chamber, i.e. a composite line system. The frequency response characteristics are investigated analytically and experimentally. The theoretical analysis is base on unsteady laminar flow of a viscous compressible fluid. It is generally difficult to obtain exactly the frequency equation of these lines system and its solutions in consideration of viscosity of hydraulic fluid, because the diameters of two pipes and length are different. The effect of the position where the cross-sectional area of changes suddenly, the inner radius of pipe and the volume of terminal chamber on the frequency characteristics of this composite line system are also described.

• Korean Journal of Organic Agriculture
• /
• v.18 no.1
• /
• pp.41-53
• /
• 2010

The objectives of this study were to find out determinant attributes of selecting Environment-Friendly Agricultural Products (EFAP) and to analyze the degree of consumer's satisfaction by using factor analysis. To identify determinant attributes of EFAP, a series of household surveys were conducted on housewives residing in Seoul. The sample size of the survey is 247 respectively. The main results of this study are summarized as follows. Firstly, the degree of consumer's satisfaction and loyalty is higher than before. Secondly, the consumers recognized that the most important attributes in selecting EFAP is a 'taste'. Thirdly, 'price policy', 'diversity of purchasing items' and 'package design' will continuously speed up the development of EFAP in order to improve the consumer's satisfaction.

• Journal of Chest Surgery
• /
• v.22 no.2
• /
• pp.202-211
• /
• 1989

We experienced a series of animal experimental studies of the total artificial heart in 1988. So called, "Korean Heart* was used in this study, which is developed and fabricated in the Department of Biomedical Engineering, College of Med., S.N.U.. "Korean Heart" is a Rolling-Cylinder Motor-Driven type which is a newly developed electromechanical heart over the shortcomes of the previous artificial hearts, especially pneumatic type. The advantages of the "Korean Heart" are total implantability, quiet and smooth movement, small size fittable in oriental people, etc. The animal experiments were performed two times, as an assist device in sheep and total artificial heart implant experiment in calf weighing 100 kg. After total implantation, the artificial heart was well functioned in movement and hemodynamic control. So that, the calf was recovered excellently, which was able to stand up by herself and take an oral intake. Total survival time was 100 hours and the cause of death was a sudden pumping failure [electrical connection problem]. Several postoperative laboratory results almost within normal limits and no hemolysis, but in autopsy, the multiple thromboembolic findings were seen at the lung and kidney.n at the lung and kidney.

• New & Renewable Energy
• /
• v.1 no.4 s.4
• /
• pp.55-59
• /
• 2005

In this paper, a new drive system(SHS) for hybrid electric vehicle is proposed. As dual rotor hybrid electric vehicle using planetary gearsets, the SHS has the advantages of both series and parallel systems. The output speed and torque of SHS can be determined at specific point regardless of the engine's operating point. When the size of generator which is used in SHS is same as in THS, the SHS has more activities of engine control due to the ability that is operated in lower speed range. To maximize the performance of system, we carried out optimization for the three parameters that are engine, motorl and motor2. As the result of the optimization, we confirmed the SHS is more preferable to THS in fuel consumption and acceleration area.

• Korean Journal of Organic Agriculture
• /
• v.12 no.2
• /
• pp.153-169
• /
• 2004

This study attempted to identify relative evaluation to its attributes and improvement of consumer's demand in the Environment-Friendly Agricultural Products(EFAP). To identify the consumption patterns of EFAP, a series of household surveys were conducted for housewives residing in Seoul and its metropolitan area(Bundang and Ilsan). the sample size of the survey is 366 respectively. This study operated relative evaluation of EFAP by Multi-Demential Scales(MDS) about 10 attributes that this study set up. As the result, the consumers recognized that EFAP is "protection of ecosystem", "food safety", "good for growth of children", "high quality", and in case of conventional farming products is "inexpensive price", and "diversity of purchasing items". This trend has significant implications to the structure of EFAP output and how positioning strategies, and approaches should be properly formulated and implemented.