• Title/Summary/Keyword: primary function

검색결과 1,628건 처리시간 0.05초

인공위성 카메라 주반사경의 위상 최적화 (Topology Optimization of the Primary Mirror of a Multi-Spectral Camera)

  • 박강수;장수영;이응식;윤성기
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집A
    • /
    • pp.920-925
    • /
    • 2001
  • A study on the topology optimization of a multi-spectral camera for space-use is presented. A multi-spectral camera for space-use experiences degradation of optical image in the space, which can not be detected on the optical test bench on the earth. An optical surface deformation of a primary mirror, which is a principal component of the camera system, under the self-weight loading is an important factor affecting the optical performance of the whole camera system. In this study, topology optimization of the primary mirror of the camera is presented. Total mass of the primary mirror is given as a constraint to the optimization problem. The sensitivities of the objective function and constraint are calculated by direct differentiation method. Optimization procedure is carried out by an optimality criterion method using the sensitivities of the objective function and the constraint. As a preliminary example, topology optimization considering a self-weight loading is treated. For practical use, the polishing pressure is included as a loading in the topology optimization of the primary mirror. Results of the optimized design topology for the primary mirror with varying mass ratios are presented.

  • PDF

The Choice of a Primary Resolution and Basis Functions in Wavelet Series for Random or Irregular Design Points Using Bayesian Methods

  • Park, Chun-Gun
    • Communications for Statistical Applications and Methods
    • /
    • 제15권3호
    • /
    • pp.379-386
    • /
    • 2008
  • In this paper, the choice of a primary resolution and wavelet basis functions are introduced under random or irregular design points of which the sample size is free of a power of two. Most wavelet methods have used the number of the points as the primary resolution. However, it turns out that a proper primary resolution is much affected by the shape of an unknown function. The proposed methods are illustrated by some simulations.

의료기관 가정간호 환자 주돌봄자의 소진에 영향을 미치는 요인 (Factors Influencing Burnout in Primary Family Caregivers of Hospital-based Home Care Patients)

  • 양주옥;이혜경
    • 지역사회간호학회지
    • /
    • 제29권1호
    • /
    • pp.54-64
    • /
    • 2018
  • Purpose: The purpose of this study is to identify factors influencing burnout in primary family caregivers of Home Health Care Patients. Methods: Data were collected from 121 primary family caregivers of home health care patients in three different hospitals in 'D' metropolitan city and the study was conducted from August 10, 2016 to January 17, 2017. The data were analyzed using descriptive statistics, t-test, ANOVA, Pearson's Correlation Coefficient, Stepwise Multiple Linear Regression. Results: Mean scores for the nursing needs of the participants were $3.54{\pm}0.79$, the family functions were $1.24{\pm}0.58$, the burnouts were $2.74{\pm}0.49$. The burnouts were positively correlated with the nursing needs but inversely correlated with the family function. The factor that had the greatest influence on the burnouts of primary family caregivers of Home Health Care was family function (${\beta}=-.245$, p=.001), followed by patients' daily activity (${\beta}=-.213$, p=.014), age (${\beta}=.208$, p=.032), monthly nursing services cost (${\beta}=-.196$, p=.044) and nursing needs (${\beta}=.129$, p=.014). The Explanatory Power of Models was 23%. Conclusion: Individually customized home care nursing intervention programs are required to be provided in accordance with patient's family function and daily activity, monthly home care nursing service cost, nursing needs and general characteristics of primary caregivers of Home Health Care Patients such as their age, the number of family members living together, sex and the name of disease.

인공위성 카메라 주반사경의 위상최적화 (Topology Optimization of the Primary Mirror of a Multi-Spectral Camera)

  • 박강수;장수영;이응식;윤성기
    • 대한기계학회논문집A
    • /
    • 제26권6호
    • /
    • pp.1194-1202
    • /
    • 2002
  • A study on the topology optimization of a multi-spectral camera for space-use is presented. The optimization is carried out under self-weight and polishing pressure loading. A multi-spectral camera for space-use experiences degradation of optical image in the space, which can not be detected on the optical test bench on the earth. An optical surface deformation of a primary mirror, which is a principal component of the camera system, is an important factor affecting the optical performance of the whole camera system. In this study, topology optimization of the primary mirror of the camera is presented. As an objective function, a measure of Strehl ratio is used. Total mass of the primary mirror is given as a constraint to the optimization problem. The sensitivities of the objective function and constraint are calculated by direct differentiation method. Optimization procedure is carried out by an optimality criteria method. For the light-weight primary mirror design, a three dimensional model is treated. As a preliminary example, topology optimization considering a self-weight loading is treated. In the second example, the polishing pressure is also included as a loading in the topology optimization of the mirror. Results of the optimized design topology for the mirror with various mass constraints are presented.

무극 함금석영맥광상 화강암질모암에서의 원소들의 분산형태와 분산범위 (Primary Dispersion Patterns and Widths of Elements in Altered Granitic Wallrock around the Gold-bearing Quartz Veins at the Mugeug Mine)

  • 황인호;전효택
    • 자원환경지질
    • /
    • 제27권5호
    • /
    • pp.451-458
    • /
    • 1994
  • Geochemical studies on gold-bearing quartz veins and granitic wallrocks from the Mugeug mine were carried out in order to investigate primary dispersion patterns of elements and to quantify primary dispersion widths of elements with distance from the gold-bearing quartz veins. The best fitting model of dispersion pattern in altered wallrock around the gold-bearing quartz veins is an exponential function for Au, As, Sb, $Na_2O$ and Sr, and a quadratic function for CaO, $K_2O$, MnO, Ba, Rb and Cs. The primary dispersion widths are 15~343 cm in the hanging wall, and 33~173 cm in the footwall. The width of primary dispersion in the hanging wall is twice as thick as that in the footwall mainly due to the thermal effect and volatile components. The primary dispersion width is increased as the increase of gold-bearing quartz vein width and contents of As and Sb in gold-bearing quartz veins, but is not related to Au content in gold-bearing quartz veins.

  • PDF

가상화 기술을 이용한 임베디드 시스템상의 고장감내 PSTR 설계 (The Design of Fault Tolerant PSTR Using Virtualization Techniques on the Embedded System)

  • 유진호;한규종
    • 정보처리학회논문지:컴퓨터 및 통신 시스템
    • /
    • 제3권12호
    • /
    • pp.443-448
    • /
    • 2014
  • 본 논문은 가상화 기술을 이용하여 PSTR에 기반한 고장감내 설계에 관련한 연구이다. 고장감내 PSTR 모델을 가상화 기술에 기반하여 구현하게 되면 프라이머리와 쉐도우 간의 통신성능이 향상되고 각 프라이머리와 쉐도우 내의 동작에 대한 모니터링이 용이하게 된다. 기존의 PSTR 모델은 프라이머리 하드웨어와 쉐도우 하드웨어 구성을 전제로 하여 프라이머리에서 본 임무를 수행하고 쉐도우에서는 프라이머리에서 고장이 발생했을 경우 취해야 할 동작을 준비하게 된다. 쉐도우에서 이러한 동작을 준비하므로 임무에 차질이 없도록 프라이머리는 다시 주 임무를 수행할 수 있게 된다. 본 논문에서는 임베디드 환경에서 고장감내 PSTR 모델을 가상화 기술을 이용하여 구현한다.

이산 카오스 함수와 Permutation Algorithm을 결합한 고신뢰도 광영상 암호시스템 (A high reliable optical image encryption system which combined discrete chaos function with permutation algorithm)

  • 박종호
    • 정보보호학회논문지
    • /
    • 제9권4호
    • /
    • pp.37-48
    • /
    • 1999
  • 현대암호방식은 종래의 선형 대수와 수리이론을 적용한 암호통신을 벗어난 유사 잡음성을 띠는 카오스 신호를 이용한 암호통신을 적용해 오고 있다,[1-2] 본 논문은 1차 permutation 알고 리즘을 이용 하여 변환된 정보를 2차 이산 카오스 변환 함수를 이용해 암호화하는 광영상 암호시스템을 제안하여UT 다. 제안된 시스템은 키수열 발생기의 출력을 통해 영상정보를 permutation 하는 알고리즘 을 설계하였고 이에 대한 검정을 수행하였다. 또한 본 논문에서는 permutation 알고리즘을 통해 제한적인 카오스 함수 의 적용시 발생하는 문제점을 해결하고 비도를 증가시킴으로써 광영상 암호시스템에 적용 시 그 타당성 을 검정하였다. Current encryption methods have been applied to secure communication using discrete chaotic system whose output is a noise-like signal which differs from the conventional encryption methods that employ algebra and number theory[1-2] We propose an optical encryption method that transforms the primary pattern into the image pattern of discrete chaotic function first a primary pattern is encoded using permutation algorithm, In the proposed system we suggest the permutation algorithm using the output of key steam generator and its security level is analyzed. In this paper we worked out problem of the application about few discrete chaos function through a permutation algorithm and enhanced the security level. Experimental results with image signal demonstrate the proper of the implemented optical encryption system.

The Neuroprotective Potential of Cyanidin-3-glucoside Fraction Extracted from Mulberry Following Oxygen-glucose Deprivation

  • Bhuiyan, Mohammad Iqbal Hossain;Kim, Hyun-Bok;Kim, Seong-Yun;Cho, Kyung-Ok
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제15권6호
    • /
    • pp.353-361
    • /
    • 2011
  • In this study, cyanidin-3-glucoside (C3G) fraction extracted from the mulberry fruit (Morus alba L.) was investigated for its neuroprotective effects against oxygen-glucose deprivation (OGD) and glutamate-induced cell death in rat primary cortical neurons. Cell membrane damage and mitochondrial function were assessed by LDH release and MTT reduction assays, respectively. A time-course study of OGD-induced cell death of primary cortical neurons at 7 days in vitro (DIV) indicated that neuronal death was OGD duration-dependent. It was also demonstrated that OGD for 3.5 h resulted in approximately 50% cell death, as determined by the LDH release assay. Treatments with mulberry C3G fraction prevented membrane damage and preserved the mitochondrial function of the primary cortical neurons exposed to OGD for 3.5 h in a concentration-dependent manner. Glutamate-induced cell death was more pronounced in DIV-9 and DIV-11 cells than that in DIV-7 neurons, and an application of $50{\mu}M$ glutamate was shown to induce approximately 40% cell death in DIV-9 neurons. Interestingly, treatment with mulberry C3G fraction did not provide a protective effect against glutamate-induced cell death in primary cortical neurons. On the other hand, treatment with mulberry C3G fraction maintained the mitochondrial membrane potential (MMP) in primary cortical neurons exposed to OGD as assessed by the intensity of rhodamine-123 fluorescence. These results therefore suggest that the neuroprotective effects of mulberry C3G fraction are mediated by the maintenance of the MMP and mitochondrial function but not by attenuating glutamate-induced excitotoxicity in rat primary cortical neurons.

Species-specific biomass drives macroalgal benthic primary production on temperate rocky reefs

  • Spector, Michael;Edwards, Matthew S.
    • ALGAE
    • /
    • 제35권3호
    • /
    • pp.237-252
    • /
    • 2020
  • Temperate rocky reefs dominated by the giant kelp, Macrocystis pyrifera, support diverse assemblages of benthic macroalgae that provide a suite of ecosystem services, including high rates of primary production in aquatic ecosystems. These forests and the benthic macroalgae that inhabit them are facing both short-term losses and long-term declines throughout much of their range in the eastern Pacific Ocean. Here, we quantified patterns of benthic macroalgal biomass and irradiance on rocky reefs that had intact kelp forests and nearby reefs where the benthic macroalgae had been lost due to deforestation at three sites along the California, USA and Baja California, MEX coasts during the springs and summers of 2017 and 2018. We then modeled how the loss of macroalgae from these reefs impacted net benthic productivity using species-specific, mass-dependent rates of photosynthesis and respiration that we measured in the laboratory. Our results show that the macroalgal assemblages at these sites were dominated by a few species of stipitate kelps and fleshy red algae whose relative abundances were spatially and temporally variable, and which exhibited variable rates of photosynthesis and respiration. Together, our model estimates that the dominant macroalgae on these reefs contribute 15 to 4,300 mg C m-2 d-1 to net benthic primary production, and that this is driven primarily by a few dominant taxa that have large biomasses and high rates of photosynthesis and / or respiration. Consequently, we propose that the loss of these macroalgae results in the loss of an important contribution to primary production and overall ecosystem function.

Scoparone의 간 기능에 대한 영향 (Effects of Scoparone on Liver Function)

  • 최석영;조민경;홍순명;김병삼
    • 한국식품영양과학회지
    • /
    • 제27권2호
    • /
    • pp.344-349
    • /
    • 1998
  • The purpose of this study was carried out to investigate the effect of scoparone(6, 7-dimethoxyco-umarin) on liver function. Sprague-Dawley rats were treated with scoparone at a dose of 20mg/kg body weight for 5 days. Hepatic bile flow, liver weight, BSP(bromosulfophthalein) biliary excretion, alanine aminotransferase(ALT) and aspartate aminotransferase(AST) activities, malondialdehyde production and lactate dehydrogenase(LDH) release were assayed. Among them, ALT and AST activities, malondialdehyde production and LDH release were assayed by using primary hepatocyte cultures at a concentration of 0.1mg/ml. Scoparone treatment had no effect on liver weight and hepatic bile flow. Scoparone treatment not only increased BSP biliary excretion, but also recovered the decreased BSP biliary excretion by CCl4, Also scoparone significantly decreased with the increases of ALT and AST activities, malondialdehyde production and LDH release induced by CCl4. These results suggested that scoparone could protect the liver damage by chemicals via promoting the liver excretory function.

  • PDF