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A study on Calculating the Resistance characteristics analysis on Three-Dimensional Structure Using Computer Simulation Method. (컴퓨터 시뮬레이션을 이용한 3차원적 구조에서의 저항 특성 분석에 관한 연구)

  • Jang, U-Sun
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.683-686
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    • 2005
  • By now, we have been analysing the resistance values on 3 dimensional structure using experimental statical method or theoretical modeling, while devices miniaturizing reveals the limitation of the traditional methods to calculate 3 dimensional resistance. In addition, 2 dimensional analysing can not produce 3 dimensional characteristic following miniaturizing. To solve the limitations , we must do high level modeling of semi-conductor process. In this thesis, we analyzed the Laplace equation that is the basic and important for 3 dimensional structure resistance with computer simulation method and on the basis of this, analyzed the characteristic of resistance of 3 dimensional structure communication semiconductor device.

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A Study on the Optimum Software Release with without Testing Efforts (테스트노력을 고려하지 않은 소프트웨어의 최적발행)

  • Che, Gyu-Shik
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.1109-1112
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    • 2005
  • The software reliability is defined, and not only the relations between testing time and reliability, but also the relation between duration following failure fixing and reliability are studied in this paper. The release time making the testing cost to be minimum is determined through evaluating the cost for each condition. Also, the release time is determined depending on the conditions of the first reliability, considering the specified reliability. The optimum release time is determined by simultaneously studying two optimum release time issues that determine both the cost related time and the specified reliability related time. And, each condition and limitation are studied. The trend of the optimum time is also examined.

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Theoretical Analysis of the Optical Filtering Effect on a Directly Modulated Reflective Semiconductor Optical Amplifier

  • Shin, Beomsoo;Oh, Sangyeol;Lee, Jaehoon
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.1
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    • pp.5-9
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    • 2016
  • The modulation bandwidth of a reflective semiconductor optical amplifier (RSOA) is limited by carrier lifetime. Therefore, it is hard to directly modulate an RSOA with high-speed electrical signals. We theorize that an optical filter can act as an optical equalizer, compensating for the narrow bandwidth limitation imposed by the RSOA. By modeling a time-varying RSOA with a modified transfer matrix method (TMM), we simulated 25 Gbps operation of an RSOA with optical filtering effects. We investigated the impact of detuning the center wavelength of the optical filter on the modulation of an RSOA. The numerical results show that it is possible to modulate an RSOA with an optical filtering effect at 25 Gbps without electronic equalization or digital signal processing.

Performance Analysis of CAN-FD Based Network Against Network Topology (네트워크 토폴로지에 따른 CAN-FD 통신 영향성 분석)

  • Seo, Sukhyun
    • IEMEK Journal of Embedded Systems and Applications
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    • v.12 no.6
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    • pp.351-358
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    • 2017
  • The most common communication interface for automotive electronic control devices is CAN (Controller Area Network). Sine CAN was first adopted to Daimler vehicles in 1991, all of automobile manufacturers use the CAN communication for in-vehicle networks. However, as the number of electronic control devices connected to the CAN network rapidly increases, the CAN protocol reaches the limit of technology. To overcome this limitation, Bosch introduced the new communication protocol, that is CAN-FD (Flexible Data-rate). In this paper, we analyze the characteristics and limitations of CAN-FD communication according to the topology under the in-vehicle wiring harness environment designed based on the existing classic CAN communication.

Mucopolysaccharidosis Type III: Overview and Future Therapeutic Approaches

  • Kwak, Min Jung
    • Journal of mucopolysaccharidosis and rare diseases
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    • v.3 no.1
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    • pp.1-8
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    • 2017
  • Mucopolysaccharidosis (MPS) type III, or Sanfilippo syndrome is a rare autosomal recessive lysosomal storage disorder. It is caused by a deficiency of one of four enzymes involved in the degradation of the glycosaminoglycan (GAG) heparan sulfate. The resultant cellular accumulation of heparan sulfate causes various clinical manifestations. MPS III is divided into four subtypes depending on the deficient enzyme: MPS IIIA, MPS IIIB, MPS IIIC and MPS IIID. All the subtypes show similar clinical features and are characterized by progressive degeneration of the central nervous system (CNS). Main purpose of the treatment for MPS III is to prevent neurologic deterioration. However, conventional enzyme replacement therapy has a limitation due to inability to cross the blood-brain barrier. Several experimental treatment options for MPS III are being developed.

NEUROIMAGING IN NEURODEVELOPMENT (신경발달학적 신경영상학)

  • Lee Jeone-Seop
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.16 no.1
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    • pp.26-32
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    • 2005
  • Neuroimaging in neurodevelopment is a fast growing area and new imaging techniques are rapidly developed every year. In the neurodevelopmental viewpoint, the definitive psychopathology in child and adolescent psychiatric disorders are not yet known. But many consistent findings in neuroimaging studies are being published recently. This review describes the past, present, future and limitation of neuroimaging study in neurodevelopmental perspectives.

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A Case Report of Paralytic Strabismus in Childhood (마비사시 소아 환자에 대한 증례 보고 1례)

  • Kweon, Ji Hyeon;Kim, Kyeong Min;Yu, Sun Ae
    • The Journal of Pediatrics of Korean Medicine
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    • v.34 no.1
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    • pp.61-70
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    • 2020
  • Objectives The purpose of this study is to report the effectiveness of Korean medicine on treating paralytic strabismus in childhood. Methods We treated a 4-years-old patient who was diagnosed with paralytic strabismus with herbal medicine, laser acupuncture, T-acupuncture and moxibustion. Results After 5 months of the Korean medicine treatment, the child's strabismus, diplopia, and limitation of abduction were improved. There was no recurrence of the symptoms for 1 year and 4 months. Conclusions Korean medicine treatment can be effective in improving symptoms of paralytic strabismus. However, further studies are needed to demonstrate the treatment benefits to abducens nerve palsy.

Thermal Image Mosaicking Using Optimized FAST Algorithm

  • Nguyen, Truong Linh;Han, Dong Yeob
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.1
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    • pp.41-53
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    • 2017
  • A thermal camera is used to obtain thermal information of a certain area. However, it is difficult to depict all the information of an area in an individual thermal image. To form a high-resolution panoramic thermal image, we propose an optimized FAST (feature from accelerated segment test) algorithm to combine two or more images of the same scene. The FAST is an accurate and fast algorithm that yields good positional accuracy and high point reliability; however, the major limitation of a FAST detector is that multiple features are detected adjacent to one another and the interest points cannot be obtained under no significant difference in thermal images. Our proposed algorithm not only detects the features in thermal images easily, but also takes advantage of the speed of the FAST algorithm. Quantitative evaluation shows that our proposed technique is time-efficient and accurate. Finally, we create a mosaic of the video to analyze a comprehensive view of the scene.

Analysis of No-load Characteristics in LLC Resonant Converter (LLC 공진형 컨버터의 무부하 특성 분석)

  • Kwon, Min-Jun;Lee, Woo-Cheol
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.3
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    • pp.398-405
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    • 2018
  • LLC resonant converter is popular with industrial fields because it can be achieved high efficiency by zero voltage switching (ZVS). As interest grew, analysis of characteristics in LLC resonant converter have been actively studied. Generally, characteristic of LLC resonant converter is analyzed based on first harmonic approximation(FHA). The FHA analysis represents the characteristics of LLC resonant converter by obtaining the series resonant operation. FHA analysis of LLC resonant converter in load condition is correct. but it is not correct in no load condition. This paper proposed analysis of characteristics considering the parasitic components to overcome the limitation of FHA and analyze no-load characteristics. The validity of the proposed method has been investigated by simulation and experimental results.

Estimation of Antenna Correlation Coefficient of N-Port Lossy MIMO Array

  • Saputro, Susilo Ady;Nandiwardhana, Satya;Chung, Jae-Young
    • ETRI Journal
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    • v.40 no.3
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    • pp.303-308
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    • 2018
  • This paper proposes a simple yet accurate method for estimating the antenna correlation coefficient (ACC) of a high-order multiple-input multiple-output (MIMO) antenna. The conventional method employed to obtain the ACC from three-dimensional radiation patterns is costly and difficult to measure. An alternate method is to use the S-parameters, which can be easily measured using a network analyzer. However, this method assumes that the antennas are highly efficient, and it is therefore not suitable for lossy MIMO antenna arrays. To overcome this limitation, we define and utilize the non-coupled radiation efficiency in the S-parameter-based ACC formula. The accuracy of the proposed method is verified by the simulation results of a 4-port highly coupled lossy MIMO array. Further, the proposed method can be applied to N-port arrays by expanding the calculation matrix.