• Journal of information and communication convergence engineering
• /
• 제7권4호
• /
• pp.545-550
• /
• 2009

A method fully utilizing multiscale line filter responses is presented to estimate the point spread function(PSF) of a CT scanner and diameters of small tubular structures based on the PSF. The estimation problem is formulated as a least square fitting of a sequence of multiscale responses obtained at each medical axis point to the precomputed multiscale response curve for the ideal line model. The method was validated through phantom experiments and demonstrated through phantom experiments and demonstrated to accurately measure small-diameter structures which are significantly overestimated by conventional methods based on the full width half maximum(FWHM) and zero-crossing edge detection.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.1763-1766
• /
• 2003

Millimeter-wave networking is composed of narrow beam link. it is very substantial that beam connecting point to point is fixed in right direction. It is major requirement in the beam network to keep the beam in best direction. In this paper, We propose the method to find a best suited direction of the antenna's beam using the Genetic Algorithm (GA) in point-to-point link. Proposed method presume that each station knows his direction ${\theta}_1$ , ${\theta}_2$ at every step of GA, then it can be expected that GA is possible to search the ideal solution. Intensity of the received signal is evaluated by the multiplication of lengths to the point which the lobe meets with the horizontal line.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
• /
• pp.274-277
• /
• 2003

Millimeter-wave networking is composed of narrow beam link. High directivity of the beam provides either advantage or disadvantage in comparison with conventional wide-lobe microwave communications. In such networks, it is very substantial that beam connecting point to point is fixed in right direction. It is major requirement in the beam network to keep the beam in best direction. In this paper, We propose the method to find a best suited direction of the antenna's beam using the Genetic Algorithm in point-to-point link. Proposed method presume that each station knows his direction $\theta$$_1$,$\theta$$_2$ at every step of Genetic Algorithm, then it can be expected that GA is possible to search the ideal solution. Intensity of the received signal is evaluated by the multiplication of lengths to the point which the lobe meets with the horizontal line.

• Spatial Information Research
• /
• 제11권1호
• /
• pp.1-12
• /
• 2003

현재 개별공시지가를 산정하는 과정에서 비교표준지를 선정하는 작업은 지적 담당공무원의 수작업에 의하여 이루어지고 있다. 한정된 시간에 많은 개별필지의 비교표준지 선정 작업으로 인하여, 객관적이고 합리적으로 비교표준지를 선정하기에는 어려움이 있다. 또한 현재 NGIS(국가지리정보체계)나 US(도시정보체계)등에 의한 국가적인 지형정보체계 구축사업이 급속도로 진전되고 있다. 이에 따라 토지의 가치평가의 한 분야인 개별토지의 지가산정 작업도 최신의 자동화된 방법을 적용할 필요성이 증대되고 있다. 따라서, 본 연구에서는 공간 다기준 의사결정 방법 중에서 AHP, Concordance, Ideal Point 방법을 이용하며 비교표준지를 자동으로 선정하였다. 세 가지 방법을 적용하여 나온 결과를 현재의 비교표준지와 비교하여본 결과, Ai)p 방법이 가장 현실성이 있는 대안으로 선정되었다. 본 연구의 결과와 현재 사용중인 비교표준지를 연계하여 이용한다면 좀더 객관적이고 합리적인 비교표준지 선정이 이루어질 것으로 기대한다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제8권5호
• /
• pp.1654-1675
• /
• 2014

In practical wireless systems, the erroneous channel state information (CSI) sometimes deteriorates the performance drastically. This paper focuses on robust design of coordinated set planning of coordinated multi-point (CoMP) transmission, with respect to the feedback delay and link error. The non-ideal channel models involving various uncertainty conditions are given. After defining a penalty factor, the robust net ergodic capacity optimization problem is derived, whose variables to be optimized are the number of coordinated base stations (BSs) and the divided area's radius. By the maximum minimum criterion, upper and lower bounds of the robust capacity are investigated. A practical scheme is proposed to determine the optimal number of cooperative BSs. The simulation results indicate that the robust design based on maxmin principle is better than other precoding schemes. The gap between two bounds gets smaller as transmission power increases. Besides, as the large scale fading is higher or the channel is less reliable, the number of the cooperated BSs shall be greater.

• 소성∙가공
• /
• 제20권5호
• /
• pp.377-386
• /
• 2011

During stamping processes, the air trapped between sheet metal and the die cavity can be highly compressed and ultimately reduce the shape accuracy of formed panels. To prevent this problem, vent holes and passages are sometimes drilled into the based on expert experience and know-how. CAE can be also used for analyzing the air behavior in die cavity during stamping process, incorporating both elasto-plastic behavior of sheet metal and the fluid dynamic behavior of air. This study presents sheet metal forming simulation combined simultaneously with simulation of air behavior in the die cavity. There are three approaches in modeling of air behavior. One is a simple assumption of the bulk modulus having a constant pressure depending on volume change. The next is the use of the ideal gas law having uniform pressure and temperature in air domain. The third is FPM (Finite point method) having non-uniform pressure in air domain. This approach enables direct coupling of mechanical behavior of solid sheet metal and the fluid behavior of air in sheet metal forming simulation, and its result provides the first-hand idea for the location, size and number of the vent holes. In this study, commercial software, PAM-$STAMP^{TM}$ and PAM-$SAFE^{TM}$, were used.

• 대순사상논총
• /
• 제25_1집
• /
• pp.87-119
• /
• 2015

Typology of religious organization is a useful analysis from the stand point of sociology of region. A study on the change of type of religious organization according to typology is a academic responsibility. This study can also make a religion prepare theoretical shape for the future of the religion. Although Daesoonjinrihoe now becomes a established sect, Daesoonjinrihoe should retain characteristics as a alternative sect. This feature as a alternative sect is an important identity of Daesoonjinrihoe which was established to criticize and overcome established sect. Dotongjingyeong is an ideal world of Daesoonjinrihoe. The foundation of Dotongjingyeong as an ideal world is essential value and reason of existence of Daesoonjinrihoe. For this reason, Daesoon jinrihoe should not just maintain its position but lead to reach the Dotongjingyeong here and now. Dotongjingyeong which should be built here and now is beyond Daesoonjinrihoe as a religious organization, because Dotongjingyeong is new heaven and new earth. Daesoonjinrihoe should put an guard against trial and error through change of type. Otherwise, Daesoonjinrihoe can not retain characteristics as an alternative sector. Now Daesoonjinrihoe may be at a revolutionary turning point for the foundation of Dotongjingyeong.

• 한국화재소방학회논문지
• /
• 제17권2호
• /
• pp.50-55
• /
• 2003

The lower flash points for the binary system, n-butanol+n-decane, were measured by Pensky-Martens closed cup tester. The experimental results showed the minimum in the flash point versus composition curve. The experimental data were compared with the values calculated by the reduced model under an ideal solution assumption and the flash point-prediction models based on the Van Laar and Wilson equations. The predictive curve based upon the reduced model deviated form the experimental data for this system. The experimental results were in good agreement with the predictive curves, which use the Van Laar and Wilson equations to estimate activity coefficients. However, the predictive curve of the flash point prediction model based on the Willson equation described the experimentally-derived data more effectively than that of the flash point prediction model based on the Van Laar equation.

• 한국실내디자인학회논문집
• /
• 제38호
• /
• pp.48-56
• /
• 2003

This study is purposed to find the transition of the perspective connected with visual modality. The perspective based on Greek optics and euclidean geometry and rediscovered in Renaissance represents the object according to the particular moment and the point of view, is a principal fact which affect architecture, the form of a city and the spatial organization and symbolizes an ideal of the times. It embodied perception which treats the space rationally on the basis of realism and became visual modality based on the separation of the seeing subject and the world of the object. The point of view became one with the vanishing point which made up the shape and after Renaissance for four hundred years a straight line, a right angle and a circle got to be favorite geometrical choices in architecture. A fixed point of view of the subject is getting to change and break up fundamentally by the new visual technologies of the modem times.

• 청정기술
• /
• 제26권4호
• /
• pp.279-285
• /
• 2020

Laboratories and industrial processes typically involve the use of flammable substances. An important property used to estimate fire and explosion risk for a flammable liquid is the flash point. In this study, flash point data at 101.3 kPa were determined using a SETA closed cup flash point tester on the following solvent mixtures: {2,2,4-trimethylpentane + methylcyclohexane}, {2,2,4-trimethylpentane + ethylbenzene}, and {2,2,4-trimethylpentane + p-xylene}. The purpose of this work is to obtain flash point data for binary mixtures of 2,2,4-trimethylpentane with three hydrocarbons (methylcyclohexane, ethylbenzene, and p-xylene), which are representative compounds of the main aromatic hydrocarbon fractions of petroleum. The measured flash points are compared with the predicted values calculated using the GE models' activity coefficient patterns: the Wilson, the Non-Random Two-Liquid (NRTL), and the UNIversal QUAsiChemical (UNIQUAC) models. The non-ideality of the mixture is also considered. The average absolute deviation between the predicted and measured lower flash point s is less than 1.99 K, except when Raoult's law is calculated. In addition, the minimum flash point behavior is not observed in any of the three binary systems. This work's predicted results can be applied to design safe petrochemical processes, such as identifying safe storage conditions for non-ideal solutions containing volatile components.