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Measurement of optical coefficients of multiple scattering media by using frequency domain spectroscopy (주파수 영역 분광법을 이용한 다중산란 매질의 광학계수 측정)

  • 전계진;윤길원;김건식;전성만;박승한
    • Korean Journal of Optics and Photonics
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    • v.10 no.5
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    • pp.357-363
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    • 1999
  • A frequency domain spectroscopic system was constructed to investigate the optical properties of multiple scattering media. The alternating current (AC) and phase lag components of backscattered light were measured by using the heterodyne detection method. Absorption and transport scattering coefficients were computed from the values based on diffusion theory. Predictions showed excellent matches in comparison with actual values of absorption and scattering. Predictable ranges of the optical coefficients were analyzed in terms of the distance between light source and detector, and modulation frequencies. A proposed compact experimental set-up using laser diodes can be utilized to estimate non-invasively the optical properties of multiple scattering media such as biological tissues.

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The Effects of Functional Electrical Stimulation on Forced Vital Capacity and Phonation Capabilities in Children with Spastic Cerebral Palsy

  • Ju, Joung-Youl;Kang, Kwon-Young;Shin, Hee-Joon
    • Journal of International Academy of Physical Therapy Research
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    • v.2 no.2
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    • pp.339-343
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    • 2011
  • The purpose of this study is to see the effect of functional electrical stimulation on forced vital capacity and alternating motion rate in children with spastic cerebral palsy. This study divided 20 children with spastic cerebral palsy into two groups; functional electrical stimulation treatment group and control group. Functional electrical stimulation treatment group had 20min per day treatment three times a week for four weeks and the control group did not have any treatment. Before and after intervention, this study measured forced vital capacity and alternate motion rate(/peo/,/teo/) for all children. Forced vital capacity showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). Alternate motion rate showed statistically significant increase for the group with functional electrical stimulation(p<.05) while the control group did not show any significant increase(p>.05). This result shows that functional electrical stimulation affected the ability of the children with spastic cerebral palsy who have decreased breathing and phonation capability.

Control of free surface shape in the electromagnetic casting process (전자기 주조공정에서의 자유표면 형상 제어)

  • 박재일;강인석
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.612-615
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    • 1996
  • In the continuous casting process, molten metal contacts the mold wall and the molten metal surface is subject to the mold oscillation. The mold oscillation results in the oscillation marks on the surface of solidified steel, which has undesirable effects on the quality of slabs. In order to reduce the oscillation marks by achieving soft contact of molten metal with the mold surface, alternating magnetic field is applied to the surface of molten metal. However, if the magnetic field strength becomes too strong, the melt flow induced by the magnetic field. causes the instability of the molten metal surface, which has also the bad influence on the slab quality. Therefore, it is very important to choose the optimal position of the inductor coil and the optimal level of electric power to minimize the surface defects. In the present work, as a first step toward the optimization problem of the process, numerical studies are performed to investigate the effects of coil position and the electric power level on the meniscus shape and the flow field. As numerical tools, the boundary integral equation method(BIEM) is used for the magnetic field analysis and the finite difference method (FDM) with orthogonal grid generation is used for the flow analysis.

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A Fabrication and Characteristics of 16x8 Reflection Type Symmetric Self Electro-optic Effect Device Array (16x8 반사형 S-SEED 어레이 제작 및 특성)

  • 김택무;이승원;추광욱;김석태;정문식;김성우;권오대;강봉구
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.30A no.10
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    • pp.33-40
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    • 1993
  • A reflection type 16x8 S-SEED array from LP(Low Pressure)-MODVD-grown GaAs/AlGaAs extremely shallow quantum well(ESQW) structures, with 4% Al fraction, has been fabricated. Its intrinsic region consists of 50 pairs of alternating 100.angs. GaAs and 100.angs. $Al_{0.04}$Ga$_{0.96}$As layers. A multilayer reflector stack of $Al_{0.04}$/Ga$_{0.96}$ As(599$\AA$)/AlAs(723$\AA$) was incorporated for the reflection plane below the p-i-n structures. The device processing after the MOCVD growth includes the mesa etching, isolation etching, insulator deposition, p & n metallization, and AR(Anti-Reflection) coating. For switching characteristics of the S-SEED in the form of p-i-n ESQW diode, the maximum optical negative resistance was observed at 856nm. Reflectance measurements showed a change from 15.6% to 43.3% for +0.9V to -6V bias. The maximum contrast ration of the S-SEED array was 2.0 and all the 128 devices showed optical bistability with contrast ratios over 2.4 at 5V reverse bias.

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Hydrogen Generation Characteristics of SMART System with Inherent $CO_2/H_2$ Separation ($CO_2/H_2$ 원천분리 SMART 시스템의 수소생산특성)

  • Ryu, Ho-Jung
    • Journal of Hydrogen and New Energy
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    • v.18 no.4
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    • pp.382-390
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    • 2007
  • To check the feasibility of SMART(Steam Methane Advanced Reforming Technology) system, an experimental investigation was performed. A fluidized bed reactor of diameter 0.052m was operated cyclically up to 10th cycle, alternating between reforming and regeneration conditions. FCR-4 catalyst was used as the reforming catalyst and calcined limestone(domestic, from Danyang) was used as the $CO_2$ absorbent. Hydrogen concentration of 98.2% on a dry basis was reached at $650^{\circ}C$ for the first cycle. This value is much higher than $H_2$ concentration of 73.6% in the reformer of conventional SMR (steam methane reforming) condition. The hydrogen concentration decreased because the $CO_2$ capture capacity decreased as the number of cycles increased. However, the average hydrogen concentration at 10th cycle was 82.5% and this value is also higher than that of SMR. Based on these results, we could conclude that the SMART system can replace SMR system to generate pure hydrogen without HTS (high tempeature shift), LTS (low temperature shift) and $CO_2$ separation process.

As-Rigid-As-Possible Dynamic Deformation with Oriented Particles (방향성 입자를 이용한 ARAP 동적 변형)

  • Choi, Min Gyu
    • Journal of Korea Game Society
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    • v.17 no.1
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    • pp.89-98
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    • 2017
  • This paper presents a novel ARAP (as-rigid-as-possible) approach to real-time simulation of physics-based deformation. To cope with one, two and three dimensional deformable bodies in an efficient, robust and uniform manner, we introduce a deformation graph of oriented particles and formulate the corresponding ARAP deformation energy. For stable time integration of the oriented particles, we develop an implicit integration scheme formulated in a variational form. Our method seeks the optimal positions and rotations of the oriented particles by iteratively applying an alternating local/global optimization scheme. The proposed method is easy to implement and computationally efficient to simulate complex deformable models in real time.

A Comparative Study on Software Reliability Model for NHPP Intensity Function Following a Decreasing Pattern (강도함수가 감소패턴을 따르는 NHPP 소프트웨어 신뢰모형에 관한 비교 연구)

  • Kim, Hee Cheul;Kim, Jong Buam;Moon, Song Chul
    • Journal of Information Technology Applications and Management
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    • v.23 no.4
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    • pp.117-125
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    • 2016
  • Software reliability in the software development process is an important issue. In infinite failure non-homogeneous Poisson process software reliability models, the failure occurrence rates per fault. can be presented constant, monotonic increasing or monotonic decreasing pattern. In this paper, the reliability software cost model considering decreasing intensity function was studied in the software product testing process. The decreasing intensity function that can be widely used in the field of reliability using power law process, log-linear processes and Musal-Okumoto process were studied and the parameter estimation method was used for maximum likelihood estimation. In this paper, from the software model analysis, we was compared by applying a software failure interval failure data considering the decreasing intensity function The decreasing intensity function model is also efficient in terms of reliability in the arena of the conservative model can be used as an alternating model can be established. From this paper, the software developers have to consider life distribution by preceding information of the software to classify failure modes which can be gifted to support.

Case study on the Fever pattern of Malaria (전형적(典型的)인 학질의 증례(證例) 보고(報告))

  • Park, Jae-Hyun
    • The Journal of Internal Korean Medicine
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    • v.19 no.2
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    • pp.451-457
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    • 1998
  • This study was performed on the bases of clinical consideration about patient who has malaria. The symptoms of malaria are periodic alternating of chills and fever on everyone, two or three days. The patients feel a chill at the first time of malaria, and have a fever, headache and sweating at the next time. The long cycle of malarial fever such as every 2 or 3 days means that it takes a turn for the worse. In this study, oriental medicine was taken based on the oriental medicine principle such as Dalwonum(達原飮), Sosihotang(小柴胡湯) and Bojungikgitang(補中益氣湯), and the patients take a turn for the better. In the process of treatment if there is no fever in the expected date of the malarial fever, it is sure to have fever in the next expected date. It is favorable that patients lose the chills first and the fever lately in the process of treatment, and we can explain that supporting healthy energy to eliminate evil(扶正祛邪). The long cycle of malarial fever such as every 4, 6 or 9 days means that it is just before the recovery.

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The Applications of Sol-Gel Derived Tin Oxide Thin Films

  • Park, Sung-Soon;John D. Mackenzie
    • The Korean Journal of Ceramics
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    • v.2 no.1
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    • pp.1-10
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    • 1996
  • Transparent conducting $SnO_2$-based thin films have been coated on float substrates such as fused quartz, and ceramic fiber cloths such as the Nexel and E-glass cloth from tin alkoxides by the sol-gel technique. Also, thin films of alternating layers of $SnO_2$ and $SiO_2$ have been fabricated by dip coating. The sheet resistance and average visible transmittance of the films were investigated in the aspect of the applications as transparent electrodes such as liquid crystal displays, photo-detectors and solar cells. The Nextel and E-glass cloths coated with antimony-doped tin oxide (ATO) had sheet resistance of as low as $20 \;ohm/{\Box}$ and $120ohm/\;{\Box}$, respectively. The promotion effects of additives as $La_2O_3$ and Pt on the ethanol gas sensing properties of the films were investigated in the aspects of the applications as an alcohol sensor and a breath alcohol checker. Possible evidence of quantum well effects in the oxide multilayers of $SnO_2$ and $SiO_2$ was investigated.

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Datamining technique for successful eCRM, CRM (성공적인 eCRM, CRM을 위한 데이터마이닝 기법)

  • Kang Rae-Goo;Lim Hee-Kyoung;Jung Chai-Yeoung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.9
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    • pp.1596-1601
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    • 2006
  • To customer management finds and forecast customer's various pattern more easily and conveniently rising by important topic that control corporation's success and failure, mmy corporations are introducing CRM and eCRM fast. At past, customer management had been managed by statisticians or special statistics package but it is trend been alternating gradually by datamining technique to do to computerize statistics process based on sudden development of IT. Field that this datamining is used representatively is CRM, eCRM. This paper applied datamining using GA referencing customer data or discount store and sale data or 2004 years. forecasted 2005 years melancholy customer by datamining and proved datamining through comparison with actuality customer data is how effective to eCRM.