• Title/Summary/Keyword: derivative work

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NEAR INFRARED SPECTROSCOPY, A POWERFUL TECHNIQUE IN HUMAN SKIN STUDY : PART I METHOD RELIABILITY AND INFLUENTIAL PARAMETERS

  • Snieder, Marchel;Wiedemann, Sophie;Hansen, Wei G.
    • 한국근적외분광분석학회:학술대회논문집
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    • 한국근적외분광분석학회 2001년도 NIR-2001
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    • pp.3101-3101
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    • 2001
  • Near Infrared spectroscopy (NIR) used on human skin measurement was explored in the past decade. Many publications in different journals and magazines discussed the feasibility of the NIR technique for cosmetic product property studies. Based upon the results of pioneers, we have pursued some work of the NIR instrument coupled with a probe module for skin measurement in vivo and vitro. In part I of this paper, the specific Near Infrared spectroscopy instrument stability, human subject conditions and other parameters, which could affect the measurements reproducibility are discussed. Second derivative NIR spectra and Principle Components Analysis (PCA) are utilised for data interpretation. In part II of this paper, the relationship of human skin moisture and ageing, the gender information and finally, the discovery of penetration depth of NIR incident light on skin are reported. A theoretical penetration depth calculation equation is proposed. In part III, the study results of a couple of commercial skin care products effect will be described. The skin lotions were applied on human skin (in vivo) in order to exam the NIR feasibility to monitor the changes of moisture level. The results are consistently positive. From our primary study, it can conclude that the NIR is potentially a very powerful instrument for skin condition diagnostics, either for cosmetic and/or for medication purposes.

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비행체 공력-구조-RF 스텔스 통합해석 시스템에 관한 연구 (An Integrated System for Aerodynamic, Structural, and RF Stealth Analysis of Flying Vehicles)

  • 박민주;이동호;명노신;조태환
    • 한국항공우주학회지
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    • 제36권1호
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    • pp.86-91
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    • 2008
  • 최근 항공기 예비설계 단계에서 여러 분야의 설계요소를 동시에 고려하는 다분야 통합설계(Multidisciplinary Design) 기법이 요구되고 있다. 본 연구에서는 CATIA를 기반으로 항공기 형상에 대한 공력, 구조, RF 스텔스의 성능 분석을 위한 통합시스템을 구축하였다. CATIA를 이용하여 공력, 구조, RF 스텔스 해석을 위한 동일 사각격자를 생성한 후 생성된 격자를 이용하여 공력특성과 구조변위를 계산하였다. 레이더 포착면적 (RCS) 계산은 사각격자로부터 삼각형 격자를 추가로 생성하여 수행하였다. 이 과정 중 각 해석분야의 입력 파일을 생성할 수 있는 변환코드를 개발하였다. 세부분야 해석기법으로 패널 코드 PANAIR, 전산구조해석 코드 NASTRAN, PO 기법에 기초한 RCS 해석코드를 사용하였다.

원자력발전소 PID 공정제어기에 대한 튜닝 최적화 방법 (A Method of Tuning Optimization for PID Controller in Nuclear Power Plants)

  • 성찬호;민문기
    • 한국압력기기공학회 논문집
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    • 제10권1호
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    • pp.1-6
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    • 2014
  • PID(Proportional, Integral, Derivative) controller is one of the most used process controllers in nuclear power plants. The optimized parameter setting of process controller contributes to the stable operation and efficiency in the operating nuclear power plants. PID parameter setting is tuned when new process control system is established or process control system is changed. It is a burdensome work for I&C(Instrument and Control) engineers to tune the PID controller because it requires a lot of experience and knowledge. When the plant is in operation, inadequate PID parameter setting can be the cause of the unstable process of the plant. Therefore the results of PID parameter setting should be compared, simulated, verified and finally optimized. The practical PID tuning methods used in process controller are tuning operation calculation(Ziegler-Nicholes, Minimum TIAE, Lambda, IMC), exclusive tuning program based on computer and Matlab application. This paper introduces the various tuning methods and suggests an optimized PID tuning process in the operating nuclear power plants.

인터넷 지식거래소와 저작권에 관한 연구 (A Study on Internet Knowledge Markets and Copyright Issues in Korea)

  • 노영희
    • 정보관리학회지
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    • 제24권1호
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    • pp.121-145
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    • 2007
  • 본 연구는 현재 상업적인 지식거래소를 통해서 유통되고 있는 다양한 유형의 지식콘텐츠들의 저작권 문제를 저작권법에 비추어 분석하고 있다. 지식거래소에 정보를 제공하는 주체는 수많은 개인, 원문DB제공업체, 국가 및 공공기관, 출판사 등 매우 다양하다. 그러나 이러한 정보제공주체와 지식거래소간에 이루어지는 저작물의 상업적인 거래에서 정작 원저작자인 개인 저자들은 빠져있다는 점을 주목할 필요가 있다. 원칙적으로 모든 저작물의 저작권은 원저작자에게 있으며, 원저작자가 저작권 이양 동의서를 통하여 2차적 저작물 생성권 등을 포함한 모든 권리를 양도하지 않는 이상 저작물의 디지털화, 원문DB화 및 지식거래소를 통한 유통 등은 저작권에 위배된다는 결론을 내릴 수 있다.

Two-dimensional modelling of uniformly doped silicene with aluminium and its electronic properties

  • Chuan, M.W.;Wong, K.L.;Hamzah, A.;Rusli, S.;Alias, N.E.;Lim, C.S.;Tan, M.L.P.
    • Advances in nano research
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    • 제9권2호
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    • pp.105-112
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    • 2020
  • Silicene is a two-dimensional (2D) derivative of silicon (Si) arranged in honeycomb lattice. It is predicted to be compatible with the present fabrication technology. However, its gapless properties (neglecting the spin-orbiting effect) hinders its application as digital switching devices. Thus, a suitable band gap engineering technique is required. In the present work, the band structure and density of states of uniformly doped silicene are obtained using the nearest neighbour tight-binding (NNTB) model. The results show that uniform substitutional doping using aluminium (Al) has successfully induced band gap in silicene. The band structures of the presented model are in good agreement with published results in terms of the valence band and conduction band. The band gap values extracted from the presented models are 0.39 eV and 0.78 eV for uniformly doped silicene with Al at the doping concentration of 12.5% and 25% respectively. The results show that the engineered band gap values are within the range for electronic switching applications. The conclusions of this study envisage that the uniformly doped silicene with Al can be further explored and applied in the future nanoelectronic devices.

Mesophase formation behavior in petroleum residues

  • Kumar, Subhash;Srivastava, Manoj
    • Carbon letters
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    • 제16권3호
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    • pp.171-182
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    • 2015
  • Mesophase pitch is an important starting material for making a wide spectrum of industrial and advanced carbon products. It is produced by pyrolysis of petroleum residues. In this work, mesophase formation behavior in petroleum residues was studied to prepare environmentally-benign mesophase pitches, and the composition of petroleum residues and its influence on the mesophase formation was investigated. Two petroleum residues, i.e., clarified oil s (CLO-1, CLO-2) obtained from fluid catalytic cracking units of different Indian petroleum refineries, were taken as feed stocks. A third petroleum residue, aromatic extract (AE), was produced by extraction of one of the CLO-1 by using N-methyl pyrrolidone solvent. These petroleum residues were thermally treated at 380℃ to examine their mesophase formation behavior. Mesophase pitches produced as a result of thermal treatment were characterized physico-chemically, as well as by instrumental techniques such as Fourier-transform infrared spectroscopy, nuclear magnetic resonance, X-ray diffraction and thermogravimetry/derivative thermogravimetry. Thermal treatment of these petroleum residues led to formation of a liquid-crystalline phase (mesophase). The mesophase formation behavior in the petroleum residues was analyzed by optical microscopy. Mesophase pitch prepared from CLO-2 exhibited the highest mesophase content (53 vol%) as compared to other mesophase pitches prepared from CLO-1 and AE.

Attenuation of β-amyloid-induced neuroinflammation by KHG21834 in vivo

  • Kim, Eun-A;Hahn, Hoh-Gyu;Kim, Tae-Ue;Choi, Soo-Young;Cho, Sung-Woo
    • BMB Reports
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    • 제43권6호
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    • pp.413-418
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    • 2010
  • Beta-Amyloid ($A{\beta}$)-induced neuroinflammation is one of the key events in the development of neurodegenerative disease. We previously reported that KHG21834, a benzothiazole derivative, attenuates $A{\beta}$-induced degeneration of cortical and mesencephalic neurons in vitro. In the present work, we show that KHG21834 reduces $A{\beta}$-mediated neuroinflammation in brain. In vivo intracerebroventricular infusion of KHG21834 leads to decreases in the numbers of activated astrocytes and microglia and level of proinflammatory cytokines such as interleukin-$1{\beta}$ and tumor necrosis factor-$\alpha$ induced by $A{\beta}$ in the hippocampus. This suppression of neuroinflammation is associated with decreased neuron loss, restoration of synaptic dysfunction biomarkers in the hippocampus to control level, and diminished amyloid deposition. These results may suggest the potential therapeutic efficacy of KHG21834 for the treatment of $A{\beta}$-mediated neuroinflammation.

자기동조에 의한 PD 형 퍼지제어시스템의 응답 개선 (The Response Improvement of PD Type FLC System by Self Tuning)

  • 최한수;이경웅
    • 제어로봇시스템학회논문지
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    • 제18권12호
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    • pp.1101-1105
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    • 2012
  • This study proposes a method for improvement of PD type fuzzy controller. The method includes self tuner using gradient algorithm that is one of the optimization algorithms. The proposed controller improves simple Takagi-Sugeno type FLC (Fuzzy Logic Control) system. The simple Takagi-Sugeno type FLC system changes nonlinear characteristic to linear parameters of consequent membership function. The simple FLC system could control the system by calibrating parameter of consequent membership function that changes the system response. While the determination on parameter of the simple FLC system works well only partially, the proposed method is needed to determine parameters that work for overall response. The simple FLC system doesn't predict the response characteristics. While the simple FLC system works just like proportional part of PID, our system includes derivative part to predict the next response. The proposed controller is constructed with P part and D part FLC system that characteristic parameter on system response is changed by self tuner for effective response. Since the proposed controller doesn't include integral part, it can't eliminate steady state error. So we include a gain to eliminate the steady state error.

잡음환경에서 구름 볼 베어링의 결함검출을 위한 ALE의 적용 (Application of ALE for detection of rolling ball bearing defects in noisy environment)

  • 김영태;최만용;김기복;박해원;박정학;김종억;류준
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2004년도 추계학술대회 논문집
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    • pp.86-91
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    • 2004
  • It is very important to detect the bearing defects in rotating machinery since the critical failure of bearing cause a machinery shutdown. However it is difficult to detect the vibration signal resulting from the initial defects of bearing because of the high level of broadband noise. A signal processing technique, called the adaptive line enhancer(ALE) as one of adaptive filter, is studied in this work. This technique is to eliminate broadband noise without a prior knowledge of the noise and signal characteristics. Also we propose the optimal methods for selecting the three main ALE parameters such as correlation length, filter order and adaptation constant used in the adaptative process. Vibration signals for three abnormal bearings, including inner and outer raceways and ball defects, were acquired from Anderon(angular derivative of radius on)meter. The experimental results showed that the proposed technique can reliably detect the bearing defective signals masked by broadband noise.

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Identification of Pharmaceuticals for process control using Near Infrared Spectroscopy and Soft Independence modeling of Class Analogy (SIMCA)

  • Cho, Chang-Hee;Kim, Hyo-Jin;Maeng, Dae-Young;Seo, Sang-Hun;Cho, Jung-Hwan
    • Near Infrared Analysis
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    • 제1권2호
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    • pp.29-33
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    • 2000
  • The identification step of raw drug materials is an indispensible procedure in the GMP manufacturing process within the pharmaceutical industry. However, wet chemistry methods for identification of drug materials, used by the various Pharmacopeia are time-consuming and expensive steps. In this paper, near-infrared spectroscopy (NIRS) has been developed for identifying eleven drug substances including calcium pantothenate, cefaclor, cefoperazone, cephradine, dextromethorphan, ehtambutol, nicotinamide, pyrozinamide, tramadol, vitamin C, and vitamin E. Also the aim of ths work is to consturct a new algorithm for calibration model using soft independence modeling of class analogy (SIMCA) with Malinowskis Indicator Function (IND), which is used for finding the number of principal components of each class of the SIMACA model. The use of NIR technique with pattern recognition to qualify raw materials can make it possible to monitor process in real time as well as to control all procedures in the pharmaceutical industry. As the result, the samples identified of 183 different batches from 11 different compounds were separated clearly by SIMCA with 2nd derivative spectra in the NIR region of 1100∼2400 nm.