• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.9 no.4
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• pp.435-445
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• 1997

It was studied the phenomena of transient freezing of an inclined water-saturated enclosure. One side of the test section was cooled and the other sides were insulated. The effects of the initial temperature, the inclination angle on the temperature field and the shape of the ice-water interface were observed. In the beginning of freezing, with increasing the inclination angle the freezing rate was increased and in the stable density layer centered $4^{\circ}C$, the freezing was fast as the convective fluid flow became small. When the initial temperature was above the $4^{\circ}C$, the frozen thickness in the upper part of inclined surface was thinner than that in the lower part, but with time the frozen thickness of upper part was thicker than that of lower part, below the $4^{\circ}C$, the frozen thickness in the upper part was thicker than that of lower part from the begining, and above the $8^{\circ}C$ in the beginning upper part was thinner with concave, but with time thicker the upper part, vanishing concave.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2750-2753
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• 2008

This paper introduce the CFD analysis for predicting the heat transfer at the Ultrasonic horn. Approximately Ultrasonic horn separates two part. One is preheating part and the other is cooling part. Temperature of preheating part rise up by $260^{\circ}C$ that make it possible to attach a chip to a semiconductor. Also there is a piezo material in the cooling part. When piezo work, it generates heat of $100^{\circ}C$. It can stand by $150^{\circ}C$. But the high temperature conducted from the preheating part has a bad affect on the piezo. These situation make it necessary cooling at piezo. Previously except of the piezo, all of them are composed of the SUS440c that has good thermal conductivity. This study shows way that not only cooling the piezo but also cutting off the conduction between preheating part and cooling part by using the Ti and Duralumin that have low thermal conductivity compare with the SUS440c. Conclusion of CFD analysis that the heat coming from the piezo can't be transferred the horn cause of the Ti and Duralumin.

• Journal of Sericultural and Entomological Science
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• v.9
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• pp.7-13
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• 1969

This experiment was carried out to know how to cut of the mulberry branches, formed by multi-stemmed pruning, which is together with the correlation between the leaf yield and total length, total diameter, or total length X total diameter of branches. The results are as follows: 1. In case of spring pruring, cutting off 5 cm high uniformly, cutting off thick one 10 cm high and cutting off slender one 5 cm high were best. 2. In case of summer pruning, cutting off upper part one 5 cm high and cutting off lower part one 10 cm high, cutting off thick one 10 cm high, slender one 5 cm high, 5 cm high uniformly were best. 3. As the result of this experiment, cutting off all the branches 5 cm high uniformly was available.

• Journal of IKEEE
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• v.25 no.3
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• pp.485-492
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• 2021

In this paper, we propose the development of a defect inspection system for polygonal containers. Embedded board consists of main part, communication part, input/output part, etc. The main unit is a main arithmetic unit, and the operating system that drives the embedded board is ported to control input/output for external communication, sensors and control. The input/output unit converts the electrical signals of the sensors installed in the field into digital and transmits them to the main module and plays the role of controlling the external stepper motor. The communication unit performs a role of setting an image capturing camera trigger and driving setting of the control device. The input/output unit converts the electrical signals of the control switches and sensors into digital and transmits them to the main module. In the input circuit for receiving the pulse input related to the operation mode, etc., a photocoupler is designed for each input port in order to minimize the interference of external noise. In order to objectively evaluate the accuracy of the development of the proposed polygonal container defect inspection system, comparison with other machine vision inspection systems is required, but it is impossible because there is currently no machine vision inspection system for polygonal containers. Therefore, by measuring the operation timing with an oscilloscope, it was confirmed that waveforms such as Test Time, One Angle Pulse Value, One Pulse Time, Camera Trigger Pulse, and BLU brightness control were accurately output.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1981-1986
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• 2004

In this study, the basic motor control system had been investigated. The controller for this study consists of two main parts, a feedforward controller part and a feedback controller part. Each part will deals with different control problems. The feedback controller deals with robustness and stability, while the feedforward controller deals with response speed. The feedforward controller, used to solve the tracking control problem, is adaptable. To make such a tracking perfect, an adaptive law based on Feedback Error Learning (FEL) is designed so that the feedforward controller becomes an inverse system of the controlled plant. The novelty of FEL method lies in its use of feedback error as a teaching signal for learning the inverse model. The theory in $H^{\infty}$-Control is selected to be applied in the feedback part to guarantee the stability and solve the robust stabilization problems. The simulation of each individual part and the integrated one are taken to clarify the study.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.40
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• pp.107-117
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• 1996

This paper considers the part assignment to workstations in flexible manufactuirng system (FMS). Parts are processed through several workstations according to processing order. The machines of each workstation can do multiple Processing functions. Therefore, a processing of a part can be processed in several workstations, which are non-identical in functional performance. Although a processing of a part can be processed in the multiple workstations, it has to be processed in only one among available several workstations, Parts are transported with unit load by automated guided vehicles (AGVs). The criteria of part assignment is to minimize the maximum value of the processing times of each workstation and the total transport times of vehicles. Model formulation is suggested, and numerical example is shown.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.1417-1424
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• 2010

To provide more safe road and better travelling service for Expressway customer, we minimize settlement of bridge backfill and properly repair the occurred settlement. So, we devide this study to two parts one is construction part and the other is management part, in construction part we remove settlement occuring elements and in management part we grasp proper repair time, and then we produce general settlement management program. In construction part, for the purpose of developing construction method of reducing settlement, we developed construction method models and they are composed of abutment back section alteration and backfill material alteration by literature reviews and site investigation of backfill settlement. And then, we carried out laboratory model test and full size field test of some developed models.

• Journal of Korean Medical classics
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• v.17 no.4
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• pp.37-56
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• 2004

In the Circular flow of Meridians(經脈), the circulation of Nutrient Gi(營氣) is that the essence Gi(精氣) of food starts from Middle Cho(中焦), via heart and lung into the ring-type round of 12 Meridians(十二經脈) in turn of hand Meridians(水經) and foot Meridians(足經), Yang Meridians(陽經) and Eum Meridians(陰經). The circulation of Defensive Gi(衛氣) is that if going out from Eum part(陰分) into Yang part(陽分), is rounding on the Yang Meridians, if going out from Yang part into Eum part, is rounding on the five Jang(五臟) in order of Kidney(腎)-Heart(心)-Lung(肺)-Liver(肝)-Spleen(脾). Because the process of accumulating the essence Gi has a property of One-way flow, it flows from terminal to the direction of body trunk, has no distinct channel with its immaterial nature. and is concentrated on the lower part to that the five Jang belong.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.57 no.9
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• pp.1660-1668
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• 2008

The WiBro was adopted to the 3G international standard. By the change of specification from Wave 1 to Wave 2, MIMO technology is applied in order to increase the speed of downlink. By MIMO the RF part of WiBro base station is increased to 2 Tx paths. Therefore, the size of RF part is bigger and material cost is increased. For reducing these demerits, the RF part which is consisted of PA, LNA, and TDD switch is designed to one complex RF unit. Also, the experimental results of the RF unit have been discussed. Since the complex RF unit is more compact than the RF part of Wave 1 base station, it can be used as the RF part of Wave 2 base station with 2T/2R MIMO.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2001.10a
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• pp.403-406
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• 2001

Number Portability means that one can use his original telephone number when he change telephone service provider, region and the kind of service. It is service provider portability which retain same number when changed the service provider. It is location portability which retain same number when changed the geographic location. It is service portability which retain same number when changed the service type. Revision of INAP(Intelligent Network Application Part) is essential part to provide number portability In this paper, we present the changed part of INAP to provide number part.