• Journal of the Korea Institute of Military Science and Technology
• /
• v.13 no.2
• /
• pp.180-187
• /
• 2010

In this paper, a global path generation method is suggested using multiple grid maps connected with the mission type of unmanned combat vehicle(UCV). In order to carry out a mission for UCV, it is essential to find a global path which is coincident with the characteristics of the mission. This can be done by considering various combat circumstances represented as grid maps such as velocity map, threat map and communication map. Cost functions of multiple grid maps are linearly combined and normalized to them simultaneously for the path generation. The proposed method is realized using $A^*$, a well known search algorithm, and cost functions are normalized in the ratio of the traverse time which is one of critical information should be provided with the operators using the velocity map. By the experiments, it is checked found global paths match with the mission type by reflecting input data of grid maps properly and the computation time is short enough to regenerate paths in real time as combat circumstances change.

• The KSFM Journal of Fluid Machinery
• /
• v.11 no.3
• /
• pp.30-35
• /
• 2008

The purpose of this study is to examine the effect of nozzle shapes on the performance and internal flow characteristics of a cross-flow type hydro turbine for wave power generation. The performance of the turbine is calculated with the variation of rotational speed for 4 types of the nozzle shape using a commercial CFD code. The results show that nozzle shape should be designed considering available head of the turbine. Best efficiencies of the turbine by 4 types of the nozzle shape do not change largely but overall performances varies mainly by the nozzle width. The output power of the cross-flow type hydro turbine changes considerably by the nozzle shape and a partial region of stage 2 in the runner blade passage produces maximum regional output power in comparison with the other runner blade passage areas.

• Current Optics and Photonics
• /
• v.5 no.4
• /
• pp.458-465
• /
• 2021

Borate nonlinear optical crystals have been used as frequency conversion devices in many fields due to their unique transparency and nonlinearity from ultraviolet to visible spectral range. In this study, we theoretically and numerically investigate the properties of broadband second harmonic generation (SHG) in the recently reported Pna2₁-Ba₃Mg₃(BO₃)₃F₃ (BMBF) crystal. The technique is based on the simultaneous achievement of birefringence phase matching and group velocity matching between interacting waves. We discussed all factors required for broadband SHG in the BMBF in terms of two types of phase matching and group velocity matching conditions, the beam propagation direction and the corresponding effective nonlinearity and spatial walk-off, and the spectral responses. The results show that bandwidths calculated in the broadband SHG scheme are 220.90 nm (for Type I) and 165.85 nm (for Type II) in full-width-half-maximum (FWHM). The central wavelength in each case is 2047.76 nm for Type I and 1828.66 nm for Type II at room temperature. The results were compared with the non-broadband scheme at the telecom C-band.

• Journal of the Korean Society of Industry Convergence
• /
• v.23 no.6_2
• /
• pp.999-1006
• /
• 2020

This study was conducted to develop an efficiency prediction program of a hydraulic secondary energy converter for calculating annual power generation of a Wavestar type wave power generator. Using the period and wave height obtained from the frequency domain analysis, the behavior of the floating body was obtained by assuming the sin function. The piston displacement and speed of the hydraulic cylinder were calculated considering the behavior of the floating body and the shape of the mechanism. The numerical simulation of the hydraulic system was performed by physically modeling the hydraulic cylinders, check valves, hydraulic motors, which are the main devices. In the future, this analysis program will be used to develop a program for estimating annual power generation of a moveable body type wave power generation device.

• Fashion & Textile Research Journal
• /
• v.17 no.3
• /
• pp.429-439
• /
• 2015

This study develops a new brassiere for new silver women. A new brassiere design was developed for the silver generation based on apreliminary survey; subsequently, a wire and no-wire type of brassier were developed after a second fitting evaluation. The results were as follows. First, in terms of brassiere design, the cup shape was designed as mold type full cup, shoulder straps were designed as camisole type with cups, bias tape was designed for body correction in the side line and mash tape was designed for easy movement below the cups. On the other side ofthe cup shape was a pocketdesigned on a support pad forthe wire type and a support panel to serve as a wire in the no-wire type brassiere. Second, brassiere patterns were designed by referencing the educational H pattern. Thetotal length was elongated by 5cmto reduce pressure when wearing a brassiere and the height of the front center increased by 8cm for the stability of the front center of the brassiere. In addition, the side line was moved back by 3cm and the width of the brassiere wings was designed widely at 10.5cm. Third, a wearing test was conducted for the wire type and the no-wire type brassiere with comparison products, using a 7-point Likert scale. Appearance results and movement tests for the wire and no-wire type showed a higher score than comparison products.

• Journal of the Korean Home Economics Association
• /
• v.36 no.10
• /
• pp.145-160
• /
• 1998

The purposes of this research were to find out general trends of family value orientations among adolescent, middle and old generation and to investigate the differences according to related variables. For this study, three kinds of questionnaire were used and the data were obtained through 1194 samples of three generation groups living in Seoul and Kwangju. The traditional trends of old generation's value orientations were outstanding while adolescents relatively showed modernized value orientations. The value differences between adolescent and middle generation were larger than between middle and old generation. Especially value orientations of children and sex-role were largely changed, but familism was relatively preserved even in adolescent generation. The family value orientations differed significantly according to gender, age, eduaction level, income, occupation, and family type. Generally middle and adolescent women showed more modernized value orientatons than men and value orientations of three generation were most likely to be correlated with family satisfaction level.

• 한국연소학회:학술대회논문집
• /
• 2012.11a
• /
• pp.225-228
• /
• 2012

Thermodynamic and economic analysis on various type of gas turbine combined cycle power plants was presented to build up the criteria for optimization of power plants. The efficiency considered about energy level difference between electricity and heat was introduced. The efficiency on power and heat generation of power plants whose have different purpose was estimated and power generation costs on various type of combined heat and power plants : fired/unfired, condensing/non-condensing mode, single/double pressure HRSG.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.11a
• /
• pp.366-368
• /
• 2007

Mr. Hur has developed the 7500KW permanent magnet synchronous generator. The 7500KW generator has dual blade system with vertical axis type generation module. The 7500KW generator will generating that it is too expensive and construction payment. The advantages of dual blade system are cheap in generation with better efficiency, and safety compact structure. But also this system has the expensive slide ring for to distribute electrical power.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2000.11a
• /
• pp.205-208
• /
• 2000

In this paper, a plate type ozonizer has been designed and manufactured to minimize the size of ozonizer. This ozonizer have following benefits: convenience of shift and installation maximize space utility. Therefore, ozone generation characteristics have been investigated by varying flow rate, supplied power and gap spacing of plate electrodes.

• Proceedings of the KIEE Conference
• /
• 2001.04a
• /
• pp.288-292
• /
• 2001

In this paper, a maximum power control of a low-cost and rugged cage-type induction generator system is proposed, where the machine-side PWM converter is used for maximum power generation and field excitation control, and the line-side PWM inverter is used for the dc link voltage control and source-side power factor control. Simulation results through Matlab Simulink have been demonstrated.