• Proceedings of the KSME Conference
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• 2001.06d
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• pp.771-776
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• 2001

By matching a well established fast throughflow code, with standard loss correlations, and an efficient optimization algorithm, a new design system has been developed, which optimizes inlet and exit flow-field parameters for each blade row of a multistage axial flow turbine. The compressible steady state inviscid throughflow code based on streamline curvature method is suitable for fast and accurate flow calculation and performance prediction of a multistage axial flow turbine. A general purpose hybrid constrained optimization package, iSIGHT has been used, which includes the following modules: genetic algorithm, simulated annealing, modified method of feasible directions. The design system has been demonstrated using an example of a 5-stage low pressure steam turbine for 800MW thermal power plant previously designed by HANJUNG. The comparison of computed performance of initial and optimized design shows significant improvement in the turbine efficiency.

• International Journal of Automotive Technology
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• v.2 no.3
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• pp.117-122
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• 2001

For a dynamic analysis of a constrained multibody system, it is necessary to have a routine for satisfying kinematic constraints. LU decomposition scheme, which is used to divide coordinates into dependent and independent coordinates, is efficient but has great difficulty near the singular configuration. Other method such as the projection matrix, which is more stable near a singular configuration, takes longer simulation time due to the large amount of calculation for decomposition. In this paper, the row space and the null space of the Jacobian matrix are proposed by using the pseudo-inverse method and the projection matrix. The equations of the motion of a system are replaced with independent acceleration components using the null space of the Jacobian matrix. Also a new hybrid method is proposed, combining the LU decomposition and the projection matrix. The proposed hybrid method has following advantages. (1) The simulation efficiency is preserved by the LU method during the simulation. (2) The accuracy of the solution is also achieved by the projection method near the singular configuration.

• Korean Journal of Cognitive Science
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• v.1 no.1
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• pp.77-102
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• 1989

This paper reports on the development of a recognition system for Korean character,numbers and punctuation marks by syntactic approach after extracting a character or punctuation mark from a page of text.First,using the projection profile(Masudaet.al.1985,Pavlidin 1981)method, we segment a page into different regions of column or row major and then extracts lines of characters from it.Considering the height,width and connectivity of character block,we proceed to extract syllables from the extracted lines.Basically we distinguish syables into six types of formal pattern(남궁재찬 1982,이주근등 1981)following the research of lee and others,and the punctuation marks and numbers into two kinds of formal patterns,and discriminate the surface structure of the extracted syllables.By Index-Removal algorithm,we subdivide them into 44 kinds of basic korean subpattern and special characters (numbers,punctuation marks)and recognize them by syntactic method(이주근등 1981.)

• International Journal of Aeronautical and Space Sciences
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• v.3 no.2
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• pp.76-81
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• 2002

A numerical simulation of wake behavior behind three-dimensional wings in ground effect is done using an indirect boundary element method (Panel Method). An integral equation is obtained by applying Green's 2nd Identity on all surfaces of the flow domain. The AIC is constructed by imposing the no penetration condition on solid surfaces, and the Kutta at the wing's trailing edge. The ground effect is included using an image method. At each time step, a row of wake panels from wings' trailing edge are convected downstream following the force-free condition. The roll-up of wake vortices behind wings in close proximity is simulated.

• Journal of Species Research
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• v.6 no.spc
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• pp.67-70
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• 2017

Three ciliate species, Australocirrus australis (Foissner, 1995) Kumar and Foissner, 2015, Rimaleptus longitrichus ($Vd^{\prime}a{\check{c}}n{\acute{y}}$ and Foissner, 2008) $Vd^{\prime}a{\check{c}}n{\acute{y}}$ and Foissner, 2012, and Frontonia subtropica Pan et al., 2013, that were previously unreported in Korea were collected from terrestrial and marine habitats in Korea. Using live observation and protargol impregnation, the three species were identified using a combination of the following characteristics: Australocirrus australis, the distance between the anterior pretransverse cirrus and the anteriormost transverse cirrus (0.6-2.1% of body length) and the arrangement of the transverse cirri (oblique row); Rimaleptus longitrichus, the arrange of contractile vacuoles and longitudinal ciliary rows anteriorly spaced; Frontonia subtropica, number of somatic kineties (approximately 115 rows) and vestibular kineties (5 rows).

• Journal of the Korean housing association
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• v.16 no.5
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• pp.21-27
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• 2005

The purpose of this study is to prepare desirable recreational pension facilities system in compliance with various characteristics of each region and to help establish policies regarding recreational pension facilities. This research is carried out by an on site inspection and the survey of the management of the recreation facilities. Jeju recreational pensions have the following characteristics : The site area is $1305{\sim}7850\;m^2$, the number of guest rooms are $8{\sim}10$, and the area of the guest rooms are $33{\sim}99\;m^2$. In addition, most of them are built with R.C. structure and the exteriors are made of artificial stones. As for plot plan, it has 5 types of prototype : type of outbuilding, arranging in a row, corridor, hall, and the composition of the other types. Although Jeju recreational pension were institutionalized to satisfy the functions as tourism recreations, they don't reflect the unique characteristics of Jeju province.

• Korean Journal of Ichthyology
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• v.20 no.1
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• pp.70-73
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• 2008

Eight specimens (330.2~431.3 mm TL) of the family Zoarcidae were collected from the costal waters of the Byeonsanbando, Yellow Sea, Korea. They were identified as a Zoarces elongatus Kner based on the following characters: a dorsal fin with 14~16 notch-shaped spinous rays, irregular 13~16 dark spots in a row along the median body and 126~132 vertebrae. We proposed a new Korean name, 'Mu-jeom-deung-ga-si-chi', for the species.

• Animal Systematics, Evolution and Diversity
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• v.39 no.3
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• pp.86-91
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• 2023

The genus Teloganopsis Ulmer belonging to the family Ephemerellidae is only known from the species of T. punctisetae (Matsumura, 1931) in the Korean Peninsula. The members of the genus Teloganopsis are characterized by the following characteristics: head and abdominal tergites without any tubercles and complex setae; forefemur with a row of long and stout setae perpendicularly; maxilla covered with dense setae. A total of 17 species had been previously recorded in this family. Here, Teloganopsis chinoi (Gose, 1980), is newly recorded in Korea which was found under a large stone in Kyeongho river. Larval habitus, habitat, line-drawings of key characters of the species, a checklist with habitus photos of Korean Ephemerellidae, and a key to the larvae of Korean Teloganopsis are provided.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.975-976
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• 1993

This talk presents the overview of the author's research and development activities on fuzzy inference hardware. We involved it with two distinct approaches. The first approach is to use application specific integrated circuits (ASIC) technology. The fuzzy inference method is directly implemented in silicon. The second approach, which is in its preliminary stage, is to use more conventional microprocessor architecture. Here, we use a quantitative technique used by designer of reduced instruction set computer (RISC) to modify an architecture of a microprocessor. In the ASIC approach, we implemented the most widely used fuzzy inference mechanism directly on silicon. The mechanism is beaded on a max-min compositional rule of inference, and Mandami's method of fuzzy implication. The two VLSI fuzzy inference chips are designed, fabricated, and fully tested. Both used a full-custom CMOS technology. The second and more claborate chip was designed at the University of North Carolina(U C) in cooperation with MCNC. Both VLSI chips had muliple datapaths for rule digital fuzzy inference chips had multiple datapaths for rule evaluation, and they executed multiple fuzzy if-then rules in parallel. The AT & T chip is the first digital fuzzy inference chip in the world. It ran with a 20 MHz clock cycle and achieved an approximately 80.000 Fuzzy Logical inferences Per Second (FLIPS). It stored and executed 16 fuzzy if-then rules. Since it was designed as a proof of concept prototype chip, it had minimal amount of peripheral logic for system integration. UNC/MCNC chip consists of 688,131 transistors of which 476,160 are used for RAM memory. It ran with a 10 MHz clock cycle. The chip has a 3-staged pipeline and initiates a computation of new inference every 64 cycle. This chip achieved an approximately 160,000 FLIPS. The new architecture have the following important improvements from the AT & T chip: Programmable rule set memory (RAM). On-chip fuzzification operation by a table lookup method. On-chip defuzzification operation by a centroid method. Reconfigurable architecture for processing two rule formats. RAM/datapath redundancy for higher yield It can store and execute 51 if-then rule of the following format: IF A and B and C and D Then Do E, and Then Do F. With this format, the chip takes four inputs and produces two outputs. By software reconfiguration, it can store and execute 102 if-then rules of the following simpler format using the same datapath: IF A and B Then Do E. With this format the chip takes two inputs and produces one outputs. We have built two VME-bus board systems based on this chip for Oak Ridge National Laboratory (ORNL). The board is now installed in a robot at ORNL. Researchers uses this board for experiment in autonomous robot navigation. The Fuzzy Logic system board places the Fuzzy chip into a VMEbus environment. High level C language functions hide the operational details of the board from the applications programme . The programmer treats rule memories and fuzzification function memories as local structures passed as parameters to the C functions. ASIC fuzzy inference hardware is extremely fast, but they are limited in generality. Many aspects of the design are limited or fixed. We have proposed to designing a are limited or fixed. We have proposed to designing a fuzzy information processor as an application specific processor using a quantitative approach. The quantitative approach was developed by RISC designers. In effect, we are interested in evaluating the effectiveness of a specialized RISC processor for fuzzy information processing. As the first step, we measured the possible speed-up of a fuzzy inference program based on if-then rules by an introduction of specialized instructions, i.e., min and max instructions. The minimum and maximum operations are heavily used in fuzzy logic applications as fuzzy intersection and union. We performed measurements using a MIPS R3000 as a base micropro essor. The initial result is encouraging. We can achieve as high as a 2.5 increase in inference speed if the R3000 had min and max instructions. Also, they are useful for speeding up other fuzzy operations such as bounded product and bounded sum. The embedded processor's main task is to control some device or process. It usually runs a single or a embedded processer to create an embedded processor for fuzzy control is very effective. Table I shows the measured speed of the inference by a MIPS R3000 microprocessor, a fictitious MIPS R3000 microprocessor with min and max instructions, and a UNC/MCNC ASIC fuzzy inference chip. The software that used on microprocessors is a simulator of the ASIC chip. The first row is the computation time in seconds of 6000 inferences using 51 rules where each fuzzy set is represented by an array of 64 elements. The second row is the time required to perform a single inference. The last row is the fuzzy logical inferences per second (FLIPS) measured for ach device. There is a large gap in run time between the ASIC and software approaches even if we resort to a specialized fuzzy microprocessor. As for design time and cost, these two approaches represent two extremes. An ASIC approach is extremely expensive. It is, therefore, an important research topic to design a specialized computing architecture for fuzzy applications that falls between these two extremes both in run time and design time/cost. TABLEI INFERENCE TIME BY 51 RULES {{{{Time }}{{MIPS R3000 }}{{ASIC }}{{Regular }}{{With min/mix }}{{6000 inference 1 inference FLIPS }}{{125s 20.8ms 48 }}{{49s 8.2ms 122 }}{{0.0038s 6.4㎲ 156,250 }} }}

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.2
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• pp.200-210
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• 2014

An active virtual impedance algorithm is newly proposed to track a sound source and to avoid obstacles while a mobile robot is following the sound source. The tracking velocity of a mobile robot to the sound source is determined by virtual repulsive and attraction forces to avoid obstacles and to follow the sound source, respectively. Active virtual impedance is defined as a function of distances and relative velocities to the sound source and obstacles from the mobile robot, which is used to generate the tracking velocity of the mobile robot. Conventional virtual impedance methods have fixed coefficients for the relative distances and velocities. However, in this research the coefficients are dynamically adjusted to elaborate the obstacle avoidance performance in multiple obstacle environments. The relative distances and velocities are obtained using a microphone array consisting of three microphones in a row. The geometrical relationships of the microphones are utilized to estimate the relative position and orientation of the sound source against the mobile robot which carries the microphone array. Effectiveness of the proposed algorithm has been demonstrated by real experiments.