• 제목/요약/키워드: Potential Functions

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슬롯 개구를 통한 평행평판 도파관 내부로의 전자파 펄스 결합문제 해석 (Analysis of Electromagnetic Pulse Coupling Via a Slot Aperture into Parallel-Plate waveguide)

  • 이영순;박의준
    • 한국전자파학회논문지
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    • 제11권7호
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    • pp.1204-1210
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    • 2000
  • 슬롯 개구를 통해 평향평판 도파관 내부를 결합되어지는 전자파 펄스(EMP)의 과도 응답을 해석하기 위한 방법을 제안하였다. 개구의 미지 등가 면 자기전류밀도에 대한 혼합 포텐셜 적분 방정식(MPIE)을 세웠고 평행평판 도파관 영역에서의 백터 및 스칼라 포텐셜 그린함수를 개선된 북소영상법을 사용하였을 때 closed form 그림함수를 사용한 결과를 계산시간을 현저히 줄일 수 있었고 본 논문이 제안한 방법의 타당성을 확인하기 위해 기존 방법의 해석결과와 비교해 보았을때 본 논문의 해석결과와 비교적 잘 일치함을 알 수 있었다.

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정확한 Closed-Form 그린함수를 이용한 코플래너 도파로 불연속 해석 (Analysis of Coplanar Waveguide Discontinuities Using Accurate Closed-Form Green's function)

  • 강연덕;송성찬;이택경
    • 한국항행학회논문지
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    • 제7권2호
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    • pp.180-190
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    • 2003
  • 실수축 상의 적분 방법에 의한 정확한 closed-form 그린함수를 이용하여 코플래너 도파로의 불연속에 대한 공간영역 full-wave 해석을 하였다. MPIE(Mixed Potential Integral Equation)를 풀기 위한 수치계산 방법으로는 삼각형 요소를 이용한 갤러킨 방법을 사용하였다. 경계면에서 삼각형 요소상의 기저함수로는 선형함수를 사용하였으며, 관측점과 전원점이 일치하는 특이점 근방의 적분 계산을 위해 면적분을 선적분 형태로 바꾸어 피적분 함수의 특이점이 사라지도록 하는 해석적인 방법을 사용하였다. 실수축 적분방법에 의한 그린함수를 이용함으로써 불연속에 대한 정확한 특성을 구하였다.

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Immunobioloical Activity of a New Benzyl Benzoate from the Aerial Parts of Solidago virga-aurea var. gigantea

  • Choi Sang Zin;Choi Sang Un;Bae Seong Yun;Pyo Suhk neung;Lee Kang Ro
    • Archives of Pharmacal Research
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    • 제28권1호
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    • pp.49-54
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    • 2005
  • The chromatographic separation of the hexane soluble fraction of the methanol extract of the aerial parts of Solidago virga-aurea var. gigantea Mo. (Compositae) led to the isolation of a new benzylbenzoate (1) together with four known benzylbenzoates (2-5). Their structures were determined as 2-methoxybenzyl-2-hydroxybenzoate (1), benzyl-2-hydroxy-6-methoxy­benzoate (2), 2-methoxybenzyl-2,6-dimethoxybenzoate (3), 2-methoxybenzyl-2-methoxy-6­hydroxybenzoate (4), and benzyl-2,6-dimethoxybenzoate (5). Their structures were established by spectroscopic methods. Biological effects of compounds, 1 and 2, were investigated in vitro usingherapeutic agents by stimulating macrophage functions, with potential use in the treat­ mouse peritoneal macrophages. The benzylbenzoates (1 and 2) could serve as immunotherapeutic agents by stimulating macrophage functions, with potential use in the treatment of infectious diseases.

Bio-functions of Marine Carotenoids

  • Hosokawa, Masashi;Okada, Tomoko;Mikami, Nana;Konishi, Izumi;Miyashita, Kazuo
    • Food Science and Biotechnology
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    • 제18권1호
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    • pp.1-11
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    • 2009
  • Carotenoids being most important pigments among those occurring in nature, have received increased interest owing to their beneficial effects on human health. An effort is made to review marine carotenoids as important bioactive compounds with reference to their presence, chemical, and biofunctional benefits they afford. The potential beneficial effects of marine carotenoids were particularly focused on astaxanthin and fucoxanthin, major marine carotenoids found in marine animals and aquatic plants, respectively. Both carotenoids show strong antioxidant activity which is attributed to quenching singlet oxygen and scavenging free radicals. The potential role of the carotenoids as dietary antioxidants has been suggested as being one of the main mechanism by which they afford their beneficial health effects such as anticancer activity and anti-inflammatory effect. Only recently, antiobesity effect and antidiabetic effect have been noted as specific and novel bio-functions of fucoxanthin. Nutrigenomic study reveals that fucoxanthin induces uncoupling protein 1 (UCP1) expression in white adipose tissue (WAT) mitochondria to lead to oxidation of fatty acids and heat production in WAT. Fucoxanthin improves insulin resistance and decreases blood glucose level, at least in part, through the down-regulation of tumor necrosis factor $\alpha$ ($TNF{\alpha}$) in WAT of animals.

Effects of Hesperidin Are Not Associated with Changes in Basal Synaptic Transmission, Theta-burst LTP, and Membrane Excitability in CA1 Neuron

  • Baek, Jin-Hee;Kim, Jae-Ick;Kaang, Bong-Kiun
    • Animal cells and systems
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    • 제13권4호
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    • pp.357-362
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    • 2009
  • Hesperidin, the most abundant polyphenolic compound found in citrus fruits, has been known to possess neuroprotective, sedative, and anticonvulsive effects on the nervous system. In a recent electrophysiological study, it was reported that hesperidin induced biphasic change in population spike amplitude in hippocampal CA1 neurons in response to both single spike stimuli and theta-burst stimulation depending on its concentration. However, the precise mechanism by which hesperidin acts on neuronal functions has not been fully elucidated. Here, using whole-cell patch-clamp recording, we revealed that hesperidin did not affect excitatory synaptic activities such as basal synaptic transmission and theta-burst LTP. Moreover, in a current injection experiment, spike number, resting membrane potential and action potential threshold also remained unchanged. Taken together, these results indicate that the effects of hesperidin on the neuronal functions such as spiking activity might not be attributable to either modification of excitatory synaptic transmissions or changes in membrane excitability in hippocampal CA1 neuron.

사료의 아미노산 조성에 따른 돼지의 단백질 축적을 나타내는 수치모델 (A Simulation Model for the protein Deposition of Pigs According to Amino Acid Composition of Feed Proteins)

  • 이옥희;김강성
    • 한국식품영양과학회지
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    • 제28권1호
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    • pp.178-190
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    • 1999
  • This study was conducted to develop a simulation model for the growth dynamics of pigs and to describe quantitatively protein deposition depending on the amino acid composition of feed protein. In the model it is assumed that the essential processes that determine the utilization of feed protein in the whole body are protein synthesis, breakdown of protein, and oxidation of amino acid. Besides, it is also assumed that occurrence of protein deposition depends on genetic potential and amino acid composition of feed protein. The genetic potential for the protein deposition is the maximum capacity of protein synthesis, being dependent on the protein mass of the whole body. To describe the effect of amino acid composition of feed on the protein deposition, a factor, which consist of ten amino acid functions and lie between 0 and 1, is introduced. Accordingly a model was developed, which is described with 15 flux equations and 11 differential equations and is composed of two compartments. The model describes non linear structure of the protein utilization system of an organism, which is in non steady state. The objective function for the simulation was protein deposition(g/day) cal culated according to the empirical model, PAF(product of amino acid functions) of Menke. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 11.8%. The simulated protein synthesis and breakdown rates(g/day) in the whole body showed a parallel behavior in the course of growth.

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Evaluation of existing bridges using neural networks

  • Molina, Augusto V.;Chou, Karen C.
    • Structural Engineering and Mechanics
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    • 제13권2호
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    • pp.187-209
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    • 2002
  • The infrastructure system in the United States has been aging faster than the resource available to restore them. Therefore decision for allocating the resources is based in part on the condition of the structural system. This paper proposes to use neural network to predict the overall rating of the structural system because of the successful applications of neural network to other fields which require a "symptom-diagnostic" type relationship. The goal of this paper is to illustrate the potential of using neural network in civil engineering applications and, particularly, in bridge evaluations. Data collected by the Tennessee Department of Transportation were used as "test bed" for the study. Multi-layer feed forward networks were developed using the Levenberg-Marquardt training algorithm. All the neural networks consisted of at least one hidden layer of neurons. Hyperbolic tangent transfer functions were used in the first hidden layer and log-sigmoid transfer functions were used in the subsequent hidden and output layers. The best performing neural network consisted of three hidden layers. This network contained three neurons in the first hidden layer, two neurons in the second hidden layer and one neuron in the third hidden layer. The neural network performed well based on a target error of 10%. The results of this study indicate that the potential for using neural networks for the evaluation of infrastructure systems is very good.

Consciousness, Cognition and Neural Networks in the Brain: Advances and Perspectives in Neuroscience

  • Muhammad Saleem;Muhammad Hamid
    • International Journal of Computer Science & Network Security
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    • 제23권2호
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    • pp.47-54
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    • 2023
  • This article reviews recent advances and perspectives in neuroscience related to consciousness, cognition, and neural networks in the brain. The neural mechanisms underlying cognitive processes, such as perception, attention, memory, and decision-making, are explored. The article also examines how these processes give rise to our experience of consciousness. The implications of these findings for our understanding of the brain and its functions are presented, as well as potential applications of this knowledge in fields such as medicine, psychology, and artificial intelligence. Additionally, the article explores the concept of a quantum viewpoint concerning consciousness, cognition, and creativity and how incorporating DNA as a key element could reconcile classical and quantum perspectives on human behaviour, consciousness, and cognition, as explained by genomic psychological theory. Furthermore, the article explains how the human brain processes external stimuli through the sensory nervous system and how it can be simulated using an artificial neural network (ANN) consisting of one input layer, multiple hidden layers, and an output layer. The law of learning is also discussed, explaining how ANNs work and how the modification of weight values affects the output and input values. The article concludes with a discussion of future research directions in this field, highlighting the potential for further discoveries and advancements in our understanding of the brain and its functions.

경락마사지가 편마비 환자의 손부종과 손기능에 미치는 효과 (The Effect of the Meridian Massage on the Hand Edema and Function of the Hemiplegic Patient)

  • 이상은;이향련
    • 성인간호학회지
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    • 제15권4호
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    • pp.520-530
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    • 2003
  • Purpose: The objective of the study was to identify the effects of the meridian massage therapy on hand edema and hand functions in patients with hemiplegia. Method: The experiment was conducted in the Oriental Medical ward of "K" hospital during the period of 2000. 12. 15 - 2001. 03. 15. Fifty five subjects with hemiplegia following a stroke participated in the study. Volumetric size of the hand and the circumference of the index finger of each patient was measured and functional points were recorded for pre and post experiment. Result: 1. Apparent decrease in volumetric size of the hand and the circumference of the index finger(p=.022. p=.021), and higher functional points(p=.003) in the experimental group in comparison to the control group. 2.Volume of hands & their functions appeared to be irrelevant(r=-.195, p=.154). 3. Circumference of the index finger & their functions also turned out to be irrelevant (r=-.110, p=.424). Conclusion: Meridian massage is an effective nursing interventional therapy to relieve hand edema and improve hand functions in hemiplegic patients and has great potential for use in a wide range of medical fields as an efficient supplementary treatment for stroke rehabilitation.

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경영혁신을 위한 일류시스템 평가구조 및 기준에 대한 연구 (An evaluation structure and criteria of Workflow Management Systems for Business Process Reengineering)

  • 김용우;김진우;문재윤;정철범;한정필
    • 경영과학
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    • 제12권3호
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    • pp.17-44
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    • 1995
  • The changing business environment requires that firms reengineer their fundamental processes in order to retain their competitive advantage. Most Business Proess Reengineering (BPR) projects, however, have failed partly because the essential enabler, ie. information technology, was unable to perpetuate the original vision. The information systems were unable to support the collaboration among the workers participating in the process. Workflow Management Systems (WfMS) have the potential to enhance not only individual performance as did traditional information systems, but also the group performance essential to the success of BPR by providing an effective means of communications through connectivity. It also enhances productivitiy through proceduralization of the fundamental processes, thus making it possible to empower the employee even while it controls the flow, and ultimately the delaly that originally made the BPR effort necessary. Therefore, though it is not a panacea, WfMS's can improve chances for the success of BPR projects. Managers who have realized this are faced with another obstacle - that of selecting the WfMS that best meets the particular organization's needs. This paper provids an evaluation structure of WfMS functions with emphasis on those functions that are essential for BPR, classifying the functions into an attribute hierarchy according to the Analytic Hierarchy Process (AHP) approach. It also suggests specific evaluation criteria for the main workflow functions provided by most vendors today, thus providing managers with a comprehensive guideline to facilitate the decision process.

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