• Title/Summary/Keyword: multiple-slit

Search Result 24, Processing Time 0.023 seconds

Multiple congenital ocular defects in a Bedlington terrier dog (Bedlington terrier의 다발성 안기형 1례)

  • Yoo, Sukjong;Ji, Dongbeom;Kim, Hwiyool;Seo, Kangmoon;Jeong, Manbok
    • Korean Journal of Veterinary Research
    • /
    • v.53 no.2
    • /
    • pp.133-136
    • /
    • 2013
  • To report multiple congenital ocular defects in a Bedlington terrier dog aged 2.5 months with blindness. Routine ophthalmic examinations were performed for the clinical signs. Menace responses and cotton ball test were absent in both eyes (OU), but pupillary light reflexes were normal in OU. Slit lamp biomicroscopy reveled corneal dystrophy, posterior subcapsular cataract, microphthalmia in OU and lenticular coloboma in the right eye. In indirect ophthalmoscopy and ultrasonography, retinal detachment and posterior lenticonus were shown in OU. It is the first report of lenticular coloboma and posterior lenticonus in a Bedlington terrier dog.

On the Effects of Electric Noise due to the Slits in the PCB Power-Distribution Network with the Differential-Mode Signaling using a Rigorous Modal Analysis Method (정확한 모드해석방법을 이용한 차동모드 급전을 가지는 PCB 전력공급회로에서의 슬릿에 의한 전기잡음의 영향 연구)

  • Kahng, Sung-Tek
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.11
    • /
    • pp.1988-1991
    • /
    • 2007
  • This study investigates the performances of the signaling techniques including differential signals for the power-distribution network(PDN)s with and without the slit, using a rigorous evaluation method 'Modal Analysis', validated by being compared to the FDTD simulation up to 5 GHz.

Optimal seismic retrofit design method for asymmetric soft first-story structures

  • Dereje, Assefa Jonathan;Kim, Jinkoo
    • Structural Engineering and Mechanics
    • /
    • v.81 no.6
    • /
    • pp.677-689
    • /
    • 2022
  • Generally, the goal of seismic retrofit design of an existing structure using energy dissipation devices is to determine the optimum design parameters of a retrofit device to satisfy a specified limit state with minimum cost. However, the presence of multiple parameters to be optimized and the computational complexity of performing non-linear analysis make it difficult to find the optimal design parameters in the realistic 3D structure. In this study, genetic algorithm-based optimal seismic retrofit methods for determining the required number, yield strength, and location of steel slit dampers are proposed to retrofit an asymmetric soft first-story structure. These methods use a multi-objective and single-objective evolutionary algorithms, each of which varies in computational complexity and incorporates nonlinear time-history analysis to determine seismic performance. Pareto-optimal solutions of the multi-objective optimization are found using a non-dominated sorting genetic algorithm (NSGA-II). It is demonstrated that the developed multi-objective optimization methods can determine the optimum number, yield strength, and location of dampers that satisfy the given limit state of a three-dimensional asymmetric soft first-story structure. It is also shown that the single-objective distribution method based on minimizing plan-wise stiffness eccentricity turns out to produce similar number of dampers in optimum locations without time consuming nonlinear dynamic analysis.

Development of a Measurement System for Curved Ship Hull Plates with Multi-Slit Structured Light (다중 슬릿 구조화 광원을 이용한 곡판 측정장치 개발)

  • Lee, Hyunho;Lee, Don Jin;Huh, Man Joo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.3
    • /
    • pp.292-299
    • /
    • 2013
  • The measurement in the manufacturing process of curved ship hull plates still depends on wooden templates as a standard instrument. The metrology-enabled automation in the shipbuilding process has been challenged instead of line measurement with wooden templates. The developed measurement system consists of a CCD camera, multiple structured laser sources and 3-DOF motion device. The system carries out measurement of curved profiles for large scale plates by an optical triangulation method. The results of experiment conducted in a manufacturing shop demonstrate the accurate and robust performance.

Multiple Antenna System for Next Generation Mobile Communication (차세대 이동 통신용 다중 안테나 시스템)

  • Han, Min-Seok;Choi, Jae-Hoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.21 no.6
    • /
    • pp.660-669
    • /
    • 2010
  • In this paper, a multiple antenna system for next generation mobile applications is proposed. The proposed MIMO antenna consists of two parallel folded monopole antennas with the length of 100 mm and spacing of 6 mm and a decoupling network which locates at the top side of a mobile handset. In order to improve the isolation characteristic at the LTE band 13, a decoupling network was added between the two antenna elements placed close to each other. The decoupling network, consisting of two transmission lines, a shunt reactive component and common ground line, is simple and compact. To obtain the wide bandwidth characteristic, an wide folded patch structure generating the strong coupling between feeding and shorting lines through the slit is used at the bottom side of a mobile handset. Also, the performance of a multiple antenna system composed of three antenna elements is analyzed.

Miniaturized Radio Frequency Choke Using Modified Stubs for High Isolation in MIMO Systems

  • Lim, Seonho;Choi, Woo Cheol;Yoon, Young Joong
    • Journal of electromagnetic engineering and science
    • /
    • v.15 no.4
    • /
    • pp.219-223
    • /
    • 2015
  • In this paper, a miniaturized radio frequency choke (RFC) using modified stubs is proposed to improve isolation characteristics in a multiple-input-multiple-output (MIMO) antenna system. The proposed RFC, based on the LC resonance, is designed to suppress the leakage current that leads to the degradation of antenna diversity performances in the MIMO antenna configuration. The proposed RFC is composed of two open stubs that are implemented on the top of the ground plane and miniaturized by adding a slit structure on the ground plane. The MIMO antennas are also designed to verify isolation performance in the LTE 2300 band (2,300-2,400 MHz). The MIMO antennas perform well with low reflection coefficient characteristics and high isolation characteristics in the whole LTE 2300 band. To evaluate the isolation in the MIMO system, the envelope correlation coefficient (ECC) is calculated, and the value is less than 0.08. The achieved ECC is regarded as a reasonable result for improving isolation performance in the frequency range of 2,300-2,400 MHz; also, radiation patterns of antenna elements are maintained regardless of the presence of RFC.

Treatment of Hydrocephalus Associated with Neurosarcoidosis by Multiple Shunt Placement

  • Kim, Sung Hoon;Lee, Sang Weon;Sung, Soon Ki;Son, Dong Wuk
    • Journal of Korean Neurosurgical Society
    • /
    • v.52 no.3
    • /
    • pp.270-272
    • /
    • 2012
  • A 31-year-old man was admitted to our hospital due to hydrocephalus with neurosarcoidosis. Ventriculo-peritoneal shunting was performed in the right lateral ventricle with intravenous methylprednisolone. Subsequently, after 4 months, additional ventriculo-peritoneal shunting in the left lateral ventricle was performed due to the enlarged left lateral ventricle and slit-like right lateral ventricle. After 6 months, he was re-admitted due to upward gaze palsy, and magnetic resonance image showed an isolated fourth ventricle with both the inlet and outlet of fourth ventricle obstructed by recurrent neurosarcoidosis. Owing to the difficulty of using an endoscope, we performed neuronavigator-guided ventriculo-peritoneal shunting via the left lateral transcerebellar approach for the treatment of the isolated fourth ventricle with intravenous methyl prednisolone. The patient was discharged with improved neurological status.

BETTER UNDERSTANDING OF THE BIOLOGICAL EFFECTS OF RADIATION BY MICROSCOPIC APPROACHES

  • Kim, Eun-Hee
    • Nuclear Engineering and Technology
    • /
    • v.40 no.7
    • /
    • pp.551-560
    • /
    • 2008
  • Radiation has stochastic aspects in its generation, its choice of interaction mode during traveling in media, and its impact on living bodies. In certain circumstances, like in high dose environments resulting from low-LET radiation, the variance in its impact on a target volume is negligible. On the contrary, in low dose environments, especially when they are attributed to high-LET radiation, the impact on the target carries with it a large variance. This variation is more significant for smaller target volumes. Microdosimetric techniques, which have been developed to estimate the distribution of radiation energy deposited to cellular and subcellular-sized targets, contrast with macrodosimetric techniques which count only the average value. Since cells and DNA compounds are the critical targets in human bodies, microdosimetry, or dose estimation by microscopic approach, helps one better analyze the biological effects of radiation on the human body. By utilizing microbeam systems designed for individual cell irradiation, scientists have discovered that human cells exhibit radiosensitive reactions without being hit themselves (bystander effect). During the past 10 or more years, a new therapeutic protocol using discontinuous multiple micro-slit beams has been investigated for its clinical application. It has been suggested that the beneficial bystander effect is the essence of this protocol.

Cytologic Features of an Angiosarcoma in Pleural Fluid - A Case Report - (흉수의 혈관육종의 세포학적 소견 - 1예 보고 -)

  • Chu, Young-Chae;Park, In-Seo;Kim, Yoon-Ju;Han, Hye-Seung;Han, Jee-Young
    • The Korean Journal of Cytopathology
    • /
    • v.10 no.1
    • /
    • pp.61-66
    • /
    • 1999
  • Angiosarcomas are rare tumors, seen most commonly in the skin and soft tissue of head and neck legion. But it has been described in numerous body sites including thyroid, breast, liver, spleen, bone, etc.. Their biological behaviors depend on the microscopic grade, site of origin, and multifocality. We report the unique cytological features of an angiosarcoma in pleural fluid. A 61-year-old woman presented with a 6 month history of dyspnea on exertion and chest pain. Chest computerized tomography(CT) revealed multiple subpleural small nodules in the right lung and widespread all space consolidation and pleural effusion in the left lung. CT of liver revealed multiple small low attenuated lesion. The smears obtained from pleural fluid showed hypocellularity with a hemorrhagic background. The tumor cells were highly pleomorphic oval or spindle in shape and presented singly, in loose groups, in knitted syncytial aggregates, and in acinar pattern. Their nuclei had vesicular chromatin with delineated, thick nuclear membranes and occasionally a large eosinophilic, prominent nucleolus. The cytoplasm was plump, thin or protected in spindly fashion. Almost ail tumor cells showed variable sized intracytoplasmic vacuoles and their nuclei were sometimes crescentic by a huge vacuole. Occasional binucleated tumor cells and mitotic figures were present. Cellular debris and streaky materials were identified. Needle biopsy specimen from the pleura revealed anastomosing slit-like spaces lined by pleomorphic tumor cells. The tumor cells showed a strong reactivity for CD31 and vimentin and focal weak reactivity for factor VIII-related antigen.

  • PDF

Assessment of Multiple Delamination in Laminated Composites for Aircrafts using X-ray Backscattering (X-ray 후방산란 기술을 이용한 항공기용 복합재료의 다중 층간 박리 평가)

  • Kim, Noh-Yu
    • Journal of the Korean Society for Nondestructive Testing
    • /
    • v.30 no.1
    • /
    • pp.46-53
    • /
    • 2010
  • A Compton X-ray backscatter technique has been developed to quantitatively assess impact damage in quasi-isotropic laminated composites made by a drop-weight tester. X-ray backscatter imaging system with a slit-type camera is constructed to obtain a cross-sectional profile of impact-damaged laminated composites from the electron-density variation of the cross section. A nonlinear scattering model based on Boltsman equation is introduced to compute Compton X-ray backscattering field for the defect assessment. An adaptive filter is also used to reduce noises from many sources including quantum noise and irregular distributions of fibers and matrix in composites. Delaminations masked or distorted by the first delamination are detected and characterized effectively by the Compton X-ray backscatter technique, both in width and location, by application of error minimization algorithm.