853 resultados para Technology-based Firms
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地理信息系统是现代地理学与空间信息科学相结合的产物 ,经过 30多年的发展 ,它现已成为地学与计算机科学的交叉学科领域的一个研究热点 ,在自身的发展及应用方面取得了重大的突破 .对GIS的发展历史进行了简要的回顾 ,就GIS的结构、功能、分类等问题进行了探讨 ,并对GIS今后的发展动向、研究领域的分化等问题进行了预测和论述
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Sea surface salinity is a key physical parameter in ocean science. It is important in the ocean remote sensing to retrieve sea surface salinity by the microwave probe technology. Based on the in situ measurement data and remote sensing data of the Yellow Sea, we have built a new empirical model in this paper, which can be used to retrieve sea surface salinity of the Yellow Sea by means of the brightness temperature of the sea water at L-band. In this model, the influence of the roughness of the sea surface is considered, and the retrieved result is in good agreement with the in situ measurement data, where the mean absolute error of the retrieved sea surface salinity is about 0.288 psu. This result shows that our model has greater retrieval precision compared with similar models.
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本文针对基于马尔可夫随机场模型(MRF)的图像分割技术进行研究,通过深入分析马尔可夫随机场模型用于图像分割时的优缺点,提出了改进方案,将其用于单帧图像的无监督分割和动态场景下的运动目标分割。主要研究内容包括以下几部分。 第一部分详细介绍了马尔可夫随机场模型,包括邻域系统和基团的概念、初始标记场的获取、能量函数的确立和MAP估算方法。 第二部分针对噪声图像的预处理,提出一种多尺度双边滤波算法来综合不同尺度下双边滤波的去噪效果。为降低双边滤波的计算复杂性,提出一种双边滤波快速计算方法。该算法能够在去除噪声的同时较好地保留边缘。 第三部分针对MRF模型用于图像分割中遇到的过平滑问题,定义了一种间断自适应高斯马尔可夫随机场模型(DA-GMRF),提出一种基于该模型的无监督图像分割方法。利用灰度直方图势函数自动确定分类数及分割阈值,进行多阈值分割得到标记场的初始化,用Metroplis采样器算法进行标记场的优化,得到最终的分割结果。该方法考虑了平滑约束在图像边缘处的自适应性,避免了边缘处的过平滑,将其应用于无监督图像分割取得了较好的效果。 第四部分针对动态场景下的运动目标分割,提出一种基于间断自适应时空马尔可夫随机场模型的运动目标分割方法。解决了传统时空马尔可夫随机场模型不能对运动造成的显露遮挡现象进行处理问题,也克服了全局一致平滑假设造成的过平滑问题。帧差图像二值化得到初始标记场,初始标记场进行‘与’操作获得共同标记场,用Metroplis采样器算法实现共同标记场的优化。该方法既使用了平滑约束,而又保留了间断,从而使分割得到的运动目标边缘更加准确。
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在关于移动机器人的诸多研究领域中,机器人自定位是十分关键的技术,是实现机器人自主运动和其他任务的基础,而且涉及领域广泛,有很多难点有待解决,因而是一个具有重要研究价值的课题。 本论文以沈阳新松机器人股份有限公司自主研发的家庭服务机器人为研发平台,系统地研究了基于计算机视觉的室内移动机器人自定位问题,成功设计了基于单目视觉人工路标以及粒子滤波的室内移动机器人自定位系统。 本文首先根据室内移动机器人自主导航定位的要求,设计了一种简易美观的新型视觉人工路标,并且研究与实现了该路标的实时准确检测以及不同路标的识别。 其次,在位姿计算方面,本文研究了共面P4P(4点透视)问题的解法及其在位姿计算方面的应用,并分析比较了两种不同P4P解法的优缺点,成功地将两种算法结合起来用于机器人位姿计算。 最后,在机器人自定位方面,本文将单目彩色摄像机作为传感器,在基于贝叶斯滤波理论的自定位理论框架下,利用粒子滤波自定位方法融合视觉信息与码盘信息,实现了自主移动机器人的自定位。 实践证明,本文设计的基于单目视觉人工路标的自定位系统能够成功地应用在室内移动机器人上,具有较高的应用推广价值。
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随着计算机网络、通信和控制技术的发展,以太网技术在工业控制领域中的应用倍受关注。但控制系统对高可用性和稳定性的要求限制了工业以太网的发展。同时面对国内工业生产的安全现状,基于工业以太网技术的控制系统越来越多的被用于安全仪表系统(Safety Instrumented System SIS)中,所以迫切需要开展总线安全技术的研究工作,提高工业以太网控制系统的安全性和可用性。 为了满足总线控制系统对工业以太网的安全性和可用性要求,本文重点研究了基于工业以太网的高可用性网络技术,提出了三种网络冗余协议,描述了设计和开发过程,最后,通过实验数据给出了性能分析。 论文首先介绍了工业以太网和高可用性网络技术在控制领域的应用情况。分析了目前普遍应用的环网冗余技术,包括通用的生成树协议、快速生成树协议和自动化厂商自己开发的专用环网冗余协议。讨论了以上环网冗余协议在高可用性控制系统中应用的不足。 论文针对环网冗余协议在故障恢复时间等方面的不足,设计了三种基于工业以太网的网络冗余协议:单网冗余协议、双网备份冗余协议和双网并行冗余协议。本文所设计的网络冗余协议都要求将冗余管理下放到节点设备,实现分布式的冗余管理,冗余节点和非冗余节点能够同时在网络中并存,而且所有的冗余管理对于上层应用协议具有透明性。但是每种网络冗余协议在拓扑结构、故障探测和故障恢复方面各不相同。结合EPA(Ethernet for Plant Automation EPA)通信协议栈,选择合适的软硬件环境,本文实现了所设计的三种网络冗余协议,包括协议栈结构,帧结构和通信过程。 为了对网络冗余协议的进行功能测试和性能评估,论文提出了故障恢复时间,故障定位时间等评估指标,在实验室环境下搭建了测试网络平台,针对每个评估指标设计了测试方案,最后给出了每个网络冗余协议的性能和测试结果。
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本文介绍了基于工业以太网的载人潜水器的信息显示与存储技术。详细地描述了该系统的软件结构及各相关模块的特点,并对系统中数据信息流的传递显示与存储做了详细的介绍。目前,该系统已在水池中进行了实验,实验效果良好。
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利用反共振原理可有效减小振动机械对基础的作用,提高振动机械的寿命。建立了原点反共振振动机的动力学模型,阐明了其工作原理。以工作体和下质体振幅稳定为核心,分析了各系统参数一定时质量比和反共振频率比对系统振幅稳定性的影响情况,得到了作为组合参数时质量比和反共振频率比分别与上下质体动力放大因子的关系曲面,由此可得到满足工艺要求并能保证振幅稳定的参数区间,为各类反共振振动机设计提供了重要依据。研究了物料质量波动对系统振幅稳定性的影响和反共振点的漂移情况,揭示了对反共振机激振频率进行控制的必要性。在合理动力学参数组合的前提下通过引入控制技术,有效地提高了反共振振动机的工作机体和下质体的振幅稳定性。
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异构分布计算环境中多数据库的集成与互操作是CIMS环境下信息集成的一个主要研究领域。本文在分析这方面研究成果的基础上,结合CIMS环境下信息集成的需求,提出了一种基于视图对象(ViewObject)机制的多库集成与互操作技术,其基本思想是通过视图对象的机制对多种数据源中的数据进行多层抽象与封装,以满足CIMS环境下不同层次的应用集成需求。文中还以公共对象请求代理结构(CORBA)为基础提出了基于对象请求代理(ORB)的多数据库集成与互操作系统VO-MDBS的实现机制。
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为了实现轴类零件的修复,搭建基于激光熔覆技术的绿色再制造系统,该系统由功率为6kW的CO2激光器、四轴工作台、送粉机构、数控系统等硬件设备和激光绿色再制造系统驱动软件组成。以轴类为典型零件、Ni60A合金粉末为熔覆材料,对激光绿色再制造工艺技术进行研究。通过研究分析激光功率、熔覆速度、送粉量、熔覆间距等主要参数对熔覆层高度、宽度和熔覆层质量等的影响情况,获得了轴类零件激光修复的最佳工艺参数组合,实现基于激光熔覆的绿色再制造技术在生产实践中的应用。
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Exploration study proves that East sea shelf basin embeds abundant hydrocarbon resources. However, the exploration knowledge of this area is very low. Many problems in exploration are encountered here. One of them is that the gas reservoir of this area, with rapid lateral variation, is deeply buried. Correlation of Impendence between sandstone, gas sand and shale is very poor. Another problem is that the S/N ratio of the seismic data is very low and multiples are relatively productive which seriously affect reservoir identification. Resolution of the seismic data reflected from 2500-3000 meter is rather low, which seriously affects the application of hydrocarbon direct identification (HDI) technology. This research established a fine geological & geophysical model based on drilling、well logging、geology&seismic data of East sea Lishui area. A Q value extraction method from seismic data is proposed. With this method, Q value inversion from VSP data and seismic data is performed to determine the subsurface absorption of this area. Then wave propagation and absorption rule are in control. Field acquisition design can be directed. And at the same time, with the optimization of source system, the performance of high resolution seismic acquisition layout system is enhanced. So the firm foundation is ensured for east sea gas reservoir exploration. For solving the multiple and amplitude preserving problems during the seismic data processing, wave equation pre-stack amplitude preservation migration and wave equation feedback iteratively multiple attenuation technologies are developed. Amplitude preservation migration technology can preserve the amplitude of imaging condition and wave-field extrapolation. Multiple removing technology is independent of seismic source wavelet and velocity model, which avoiding the weakness of Delft method. Aiming at the complicated formation condition of the gas reservoir in this area, with dissecting typical hydrocarbon reservoir, a series of pertinent advanced gas reservoir seismic identification technologies such as petrophysical properties analyzing and seismic modeling technology、pre-stack/post-stack joint elastic inversion, attribute extraction technology based on seismic non-stationary signal theory and formation absorption characteristic and so on are studied and developed. Integrated analysis of pre-stack/post-stack seismic data, reservoir information, rock physics and attribute information is performed. And finally, a suit of gas reservoir identification technology is built, according to the geological and geophysical characteristics of this area. With developed innovative technologies, practical application and intergrated interpretation appraisal researches are carried out in Lishui 36-1.The validity of these technologies is tested and verified. Also the hydrocarbon charging possibility and position of those three east sea gas exploration targets are clearly pointed out.
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Hydrocarbon migration and accumulation are the important process to form reservoirs in sedimentary basins, and their researches are usually very difficult to be done in petroleum geology. In this paper, the west segment of northern margin of the Qaidam Basin was selected as study area. The concept of fault open coefficient, that combines multi-factors dealing with fault sealing, was applied to estimate semi-quantitatively the sealing characteristics of six faults which were considered controlling the hydrocarbon migration and accumulation. The data from boreholes were investigated to appraise the permeable characteristics of lithology combinations upon and beneath the unconformity surface. The result suggests that the basal conglomerates consist frequently the carriers. The data from boreholes and outcrops were collected to describe the sand carrier system. In order to eliminate the influence of inverse activities of the basin that made the formations be very steep, author adopts the phase method to build the basin models: for the steps before Pliocene the recovered true thickness maps were used to build the basin block; for the steps after Pliocene, the structure maps of today were used to build the basin block. During the modeling process, the results were calibrated by various measured data . the modeled results includes the dynamic evolvement course of trap form phase, vitrinite reflectance mature, the source rock expelled hydrocarbon intensity and fluid potential and petroleum plays. Author integrates the source rock expelled hydrocarbon intensity, fluid potential and carrier system and apply the migration technology based on percolation theory to simulate the oil and gas migration and accumulation course in the main accumulation times. The dominant pathways of oil and gas may show clearly the prospect distribution. Based on the hydrocarbon migration characteristics, the main control factors were synthesized, that including the effective source rock distribution, the match relationship of structural trap forming and hydrocarbon expelling from source rocks, the unconformity of Mesozoic and Cenozoic, the structures and the faults movement at Quaternary Finally, the author figures out the prospect plays in the study area.
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Ordos Basin is a typical cratonic petroliferous basin with 40 oil-gas bearing bed sets. It is featured as stable multicycle sedimentation, gentle formation, and less structures. The reservoir beds in Upper Paleozoic and Mesozoicare are mainly low density, low permeability, strong lateral change, and strong vertical heterogeneous. The well-known Loess Plateau in the southern area and Maowusu Desert, Kubuqi Desert and Ordos Grasslands in the northern area cover the basin, so seismic data acquisition in this area is very difficult and the data often takes on inadequate precision, strong interference, low signal-noise ratio, and low resolution. Because of the complicated condition of the surface and the underground, it is very difficult to distinguish the thin beds and study the land facies high-resolution lithologic sequence stratigraphy according to routine seismic profile. Therefore, a method, which have clearly physical significance, based on advanced mathematical physics theory and algorithmic and can improve the precision of the detection on the thin sand-peat interbed configurations of land facies, is in demand to put forward.Generalized S Transform (GST) processing method provides a new method of phase space analysis for seismic data. Compared with wavelet transform, both of them have very good localization characteristics; however, directly related to the Fourier spectra, GST has clearer physical significance, moreover, GST adopts a technology to best approach seismic wavelets and transforms the seismic data into time-scale domain, and breaks through the limit of the fixed wavelet in S transform, so GST has extensive adaptability. Based on tracing the development of the ideas and theories from wavelet transform, S transform to GST, we studied how to improve the precision of the detection on the thin stratum by GST.Noise has strong influence on sequence detecting in GST, especially in the low signal-noise ratio data. We studied the distribution rule of colored noise in GST domain, and proposed a technology to distinguish the signal and noise in GST domain. We discussed two types of noises: white noise and red noise, in which noise satisfy statistical autoregression model. For these two model, the noise-signal detection technology based on GST all get good result. It proved that the GST domain noise-signal detection technology could be used to real seismic data, and could effectively avoid noise influence on seismic sequence detecting.On the seismic profile after GST processing, high amplitude energy intensive zone, schollen, strip and lentoid dead zone and disarray zone maybe represent specifically geologic meanings according to given geologic background. Using seismic sequence detection profile and combining other seismic interpretation technologies, we can elaborate depict the shape of palaeo-geomorphology, effectively estimate sand stretch, distinguish sedimentary facies, determine target area, and directly guide oil-gas exploration.In the lateral reservoir prediction in XF oilfield of Ordos Basin, it played very important role in the estimation of sand stretch that the study of palaeo-geomorphology of Triassic System and the partition of inner sequence of the stratum group. According to the high-resolution seismic profile after GST processing, we pointed out that the C8 Member of Yanchang Formation in DZ area and C8 Member in BM area are the same deposit. It provided the foundation for getting 430 million tons predicting reserves and unite building 3 million tons off-take potential.In tackling key problem study for SLG gas-field, according to the high-resolution seismic sequence profile, we determined that the deposit direction of H8 member is approximately N-S or NNE-SS W. Using the seismic sequence profile, combining with layer-level profile, we can interpret the shape of entrenched stream. The sunken lenticle indicates the high-energy stream channel, which has stronger hydropower. By this way we drew out three high-energy stream channels' outline, and determined the target areas for exploitation. Finding high-energy braided river by high-resolution sequence processing is the key technology in SLG area.In ZZ area, we studied the distribution of the main reservoir bed-S23, which is shallow delta thin sand bed, by GST processing. From the seismic sequence profile, we discovered that the schollen thick sand beds are only local distributed, and most of them are distributary channel sand and distributary bar deposit. Then we determined that the S23 sand deposit direction is NW-SE in west, N-S in central and NE-SW in east. The high detecting seismic sequence interpretation profiles have been tested by 14 wells, 2 wells mismatch and the coincidence rate is 85.7%. Based on the profiles we suggested 3 predicted wells, one well (Yu54) completed and the other two is still drilling. The completed on Is coincident with the forecastThe paper testified that GST is a effective technology to get high- resolution seismic sequence profile, compartmentalize deposit microfacies, confirm strike direction of sandstone and make sure of the distribution range of oil-gas bearing sandstone, and is the gordian technique for the exploration of lithologic gas-oil pool in complicated areas.
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Manfred Beckmann, David P. Enot, David P. Overy, and John Draper (2007). Representation, comparison, and interpretation of metabolome fingerprint data for total composition analysis and quality trait investigation in potato cultivars. Journal of Agricultural and Food Chemistry, 55 (9) pp.3444-3451 RAE2008
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The authors explore nanoscale sensor processor (nSP) architectures. Their design includes a simple accumulator-based instruction-set architecture, sensors, limited memory, and instruction-fused sensing. Using nSP technology based on optical resonance energy transfer logic helps them decrease the design's size; their smallest design is about the size of the largest-known virus. © 2006 IEEE.
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BACKGROUND/AIMS: The obesity epidemic has spread to young adults, and obesity is a significant risk factor for cardiovascular disease. The prominence and increasing functionality of mobile phones may provide an opportunity to deliver longitudinal and scalable weight management interventions in young adults. The aim of this article is to describe the design and development of the intervention tested in the Cell Phone Intervention for You study and to highlight the importance of adaptive intervention design that made it possible. The Cell Phone Intervention for You study was a National Heart, Lung, and Blood Institute-sponsored, controlled, 24-month randomized clinical trial comparing two active interventions to a usual-care control group. Participants were 365 overweight or obese (body mass index≥25 kg/m2) young adults. METHODS: Both active interventions were designed based on social cognitive theory and incorporated techniques for behavioral self-management and motivational enhancement. Initial intervention development occurred during a 1-year formative phase utilizing focus groups and iterative, participatory design. During the intervention testing, adaptive intervention design, where an intervention is updated or extended throughout a trial while assuring the delivery of exactly the same intervention to each cohort, was employed. The adaptive intervention design strategy distributed technical work and allowed introduction of novel components in phases intended to help promote and sustain participant engagement. Adaptive intervention design was made possible by exploiting the mobile phone's remote data capabilities so that adoption of particular application components could be continuously monitored and components subsequently added or updated remotely. RESULTS: The cell phone intervention was delivered almost entirely via cell phone and was always-present, proactive, and interactive-providing passive and active reminders, frequent opportunities for knowledge dissemination, and multiple tools for self-tracking and receiving tailored feedback. The intervention changed over 2 years to promote and sustain engagement. The personal coaching intervention, alternatively, was primarily personal coaching with trained coaches based on a proven intervention, enhanced with a mobile application, but where all interactions with the technology were participant-initiated. CONCLUSION: The complexity and length of the technology-based randomized clinical trial created challenges in engagement and technology adaptation, which were generally discovered using novel remote monitoring technology and addressed using the adaptive intervention design. Investigators should plan to develop tools and procedures that explicitly support continuous remote monitoring of interventions to support adaptive intervention design in long-term, technology-based studies, as well as developing the interventions themselves.