H.264中整数余弦变换和周期量化的原理与分析

H.264是联合视频组正在研究制定的新一代视频压缩编码标准。H.264在它的前身H.26L的基础上进行了改进,提出了一种新的整数余弦变换方法,在降低编解码器复杂性的同时提高了编码效率。针对新整数余弦变换的特点,并考虑到H.26L中量化表的类周期性质,H.264又提出了一种新的周期量化方法。分析了H.264中这种新的整数余弦变换和周期量化的推导过程,挖掘了其扩展的可能性,最后通过在复杂度、精度和性能三个方面与H.26L中的对应算法进行比较后指出这种新算法使得H.264与H.26L相比更加简单而有效。

非周期量化间歇控制的复杂动态网络同步分析

带有多重时变时滞的复杂动态网络同步研究得到广泛关注.基于非周期量化间歇控制策略,讨论一类带有时变时滞耦合动态复杂网络的指数同步问题.通过构造适当的时间依赖Lyapunov函数,经过严格理论分析,得到保证该动态网络实现指数同步的若干充分条件。通过数值模拟验证了所得理论结果的有效性和正确性。

汽车及典型部件全生命周期减量化技术专利布局分析

为了厘清汽车及典型部件全生命周期减量化技术的发展趋势,本文借助Incopat专利分析工具对汽车及典型部件的生态设计、材料选取以及回收体系建设相关技术专利布局进行研究分析。分析结果表明,目前该领域的技术发展逐渐走向成熟;世界各国从生态设计角度出发都将研究的重点转向了新动力汽车,技术方向研究相对比较均衡;我国目前专利申请态势基本同世界保持一致,但在技术产业化发展方面尚不成熟。针对上述问题,我国在汽车及典型部件全生命周期减量化技术专利布局方面应当做出以下改进:第一,通过专利标准化战略助力专利布局,降低可拆卸部件的替换成本和报废率,让我国企业成为相关技术市场的主导者;第二,根据竞争对手的发展适时对专利布局进行调整,避免重复他人既有研发路线,发挥自身优势;第三,增强自主技术研发能力,为拓展新兴市场提供知识产权支撑;第四,加强创新主体之间的协同创新,解决新能源技术创新成本高、周期长、风险高的问题;第五,充分运用专利联盟战略,增加我国企业的议价能力和竞争综合实力。

H.264中变换和量化的SIMD优化

H.264是一个新的基于运动补偿+变换+量化+熵编码框架的视频编码国际标准。H.264中采用了大量的新技术,这些技术在提高编码效率的同时,也极大地增加了算法的复杂度。为此H.264在保证性能的前提下也做了一些优化,如变换和量化可以在16比特精度下完成,并且除了量化中需要少许乘法外,其余可以只用加法和移位实现。这些特点使得H.264中的变换和量化可以很好地使用支持单指令多数据(SIMD)的MMX技术进行进一步优化。该文首先介绍了H.264中变换和量化的实现过程和特点,接下来重点讨论了利用MMX指令对变换和量化中的关键部分进行优化的方法,最后给出了计算机仿真的结果,并对结果进行了分析。仿真结果表明:该文提出的方法可以使H.264的变换和量化模块的运算速度提高到原来的3.5～5.2倍,优化效果十分显著。

基于多次滑动均值滤波的混合储能功率分配与定容研究

为了解决混合储能系统功率分配时因模态混叠导致功率分配不精确、储能系统成本过高的问题,提出一种多次滑动均值滤波(MMAF)的功率分配方法用于削弱模态混叠现象,降低混合储能成本。首先,获取满足平抑要求的混合储能最小总功率指令,采用MMAF算法对其进行滤波,获得蓄电池与超级电容各自的功率指令,引入Pearson相关系数量化模态混叠现象,作为判断滤波次数和每次滤波滑窗大小的指标,将蓄电池和超级电容各自的功率指令作为储能定容的可行域,考虑电池荷电状态约束求取储能适配的最小额定功率和额定容量;然后,基于等效运行时间建立蓄电池全寿命周期量化模型,为经济性分析提供依据;最后,以改进的混合储能全寿命周期成本模型验证了该文方法可以有效地限制模态混叠,降低混合储能系统成本。

Failure of the Business Cycle Theory and Call for a New Theory

The US economy has emerged from the recent financial crisis and embarked on a path of recovery. A key response of the US government to the crisis was to restore the health of crisis-ridden financial institutions through direct fiscal relief and continuous quantitative easing and pumping sufficient liquidity into the financial markets. Fortunately, this process did not give rise to widely feared vicious inflation or post-crisis depression. Does this suggest that as long as the central bank offers unlimited loans or economic assistance to crisis-ridden entities to restore their health, a crisis can be averted？ If this conclusion holds true, does this mean that the theory of cyclical economic crisis has failed？ What is the new theoretical methodology to avoid economic crises？ The answers to these questions will guide us in preventing and responding to financial or economic crises in the future.

Multi-Time Scale Analysis of Runoff at the Yangtze Estuary Based on the Morlet Wavelet Transform Method

Runoff series of the Yangtze River presents an intricate variation tendency under the reinforced influence of human activities.The Morlet Wavelet Transform method has been applied to analyze the annual runoff data from 1950 to 2011 at the Yangtze River Estuary.It can clearly reveal the multi-time scales structure,break point,change and distribution of periodic variation in the different time scales of the runoff series.The main conclusions are that:1) Repeated periodic oscillations accompanied by an extremely large fluctuation are presented in the runoff series with an obvious difference between wet and dry years,and the major periods of the time series are about 3,8,16 and 23 years respectively.Among them,the presented maximum periodic oscillation is 23 years scale.2) In the 23-year time scale,the wet periods are 1950-1958,1969-1980 and 1992-2003,and the dry periods are 1959-1968,1981-1991 and 2004-2011.3) It can be predicted from the view of long time scales that the low annual runoff will likely occur in the near future.

Environmental life cycle assessment of Indian coal-fired power plants

Coal is the backbone of the Indian power sector. The coal-fired power plants remain the largest emitters of carbon dioxide, sulfur dioxide and substantial amounts of nitrogen oxides, which are associated with climate and health impacts. Various CO2 mitigation technologies （carbon capture and storage--CCS） and SO2/NOx mitigation technologies （flue gas desulfurization and selective catalytic reduction） have been employed to reduce the environmental impacts of the coal-fired power plants. Therefore, it is imperative to understand the feasibility of various mitigation technologies employed. This paper attempts to perform environmental life cycle assessment （LCA） of Indian coal-fired power plant with and without CO2, SO2 and NOx mitigation controls. The study develops new normalization factors for India in various damage categories, using the Indian emissions and energy consumption data, coupled with the emissions and particulate emission to come up with a final environmental impact of coal-fired electricity. The results show a large degree of dependence on the perspective of assessment used. The impact of sensitivities of individual substances and the effect of plant efficiency on the final LCA results is also studied.

Reproductive Cycle and Seasonal Variations in Lipid Content and Fatty Acid Composition in Gonad of the Cockle Fulvia mutica in Relation to Temperature and Food

From March 2004 to February 2005,seasonal variations in lipid content and fatty acid composition of gonad of the cockle Fulvia mutica(Reeve) were studied on the eastern coast of China in relation to the reproductive cycle and environment conditions(e.g.,temperature and food availability).Histological analysis as well as lipid and fatty acid analyses were performed on neutral and polar lipids of the gonad.Results showed that gametogenesis occurred in winter and spring at the expense of lipids previously accumulated in summer and autumn,whereas spawning occurred in summer(20.4-24.6℃).The seasonal variation in lipid content was similar to that of the mean oocyte diameter.In both neutral and polar lipids,the 20:5n-3 and 22:6n-3 levels were relatively higher than saturated fatty acids,and polyunsaturated fatty acids were abundant,with series n-3 as the predominant component.Seasonal variations in the 20:5n-3 and 22:6n-3 levels and the principal n-3 fatty acids were clearly related to the reproductive cycle.The ∑(n-3) and ∑(n-6) values were relatively high during January-May,and the associated unsaturation index was significantly higher than that in other months.The results suggest that fatty acids play an important role in the gametogenesis of F.mutica.

Development and Application of Hydrocracking Catalysts RHC-1/RHC-5 for Maximizing High Quality Chemical Raw Materials Yield

To adapt to the change in the demand of the oil refining market,two hydrocracking catalysts,RHC-1 and RHC-5,were developed to improve the quality of tail oil.The catalysts were designed based on the theory of selective ring-opening.By selecting more acidic molecular sieves,the problem of poor selectivity of conventional materials can be solved to properly match up to the hydrogenation performance of catalysts.Compared with the performance of previous catalysts,the quality of the tail oil achieved by the said catalysts is better,and the BMCI is reduced by 1—2 units.In the long cycle operation of the petroleum industry,the good quality of the tail oil has been verified and the adaptability of the process conditions is good.When the RHC-1 catalyst is used to process heavy feed under medium pressure,a BMCI value of about12 can be obtained along with a nearly 60%yield of tail oil.The total yield of chemical raw material(steaming cracking feed+catalytic reforming feed)can exceed 80%,and the hydrogen consumption has dropped by nearly 50%as compared to the conventional hydrocracking conversion rate.When processing a mixed CGO and VGO feed with the full conversion mode under a hydrogen pressure of 13.0 MPa,the RHC-5 catalyst can yield about 68.4%of heavy naphtha with a potential aromatic content of up to 50.6,while the total yield of chemical raw materials can reach more than 98%.The results of industrial application of these catalysts show that more than 30%of high quality tail oil can be obtained via processing of inferior quality feed,and its BMCI value can reach 10.7.The total yield of chemical raw materials can reach more than65%.The industrial operation process has implemented two operating cycles totaling 8 years.

Quantifying the emission＇s impact of coal mining activities on the environment and human health in process

Discharges and emissions in the coal mining process have a strong effect both on the environment and on human health. This problem is usually be a negative one and has only been recognized qualitatively, due to the lack of effective quantitative methods. Based on emergy theory and accounting methodology, a set of quantitative methods for accounting the environmental support due to pollutants emissions was first introduced. Then impacts on environment and effects on human health were quantified using the unified units. The results indicated that water pollutants caused more impacts on the environment than air pollutants did, i.e., more environmental contributions are needed to dilute and absorb water pollutants. The occupation of land caused by coal mining gangue waste stacking has led to a huge loss of environmental services over the years. Moreover, the potential damage on the human condition health caused by CO2 through climate change cannot be ignored. Finally, the impacts of mining activities on environmental and human health in unified units are shown to provide a quantitative insight into the disadvantage of coal mining. The comparable results of the method indicate the different influence of various pollutants and the contribution of ＇natural capital＇ directly. This work is a part of ongoing thermodynamic input-output analysis and life cycle analysis of coal mining systems （which are in process.）

Measurement of the Variation of Shear Velocity on Bed during a Wave Cycle

Almost all works in the field of boundary layer flow under the breaking wave consider the flow similar as the flow in an oscillating pressure tube. Although the two flows are similar, there are many differences. The results achieved in such manner are therefore also only similar to the results that can be achieved during measurements in the surf zone. Present article deals with boundary layer measurements on an inclined bottom under breaking waves. The measurements over the whole wave cycle were carried out, and the shear velocity under the breaking wave was calculated based on the measurements. It was found that there is a considerable space and time variation of the term in the surf zone. The turbulence generated during the wave breaking changes the shape of the shear velocity profile in comparison to the profile measured before breaking. As the values of shear velocity are directly correlated with the description of the whole velocity field in the wave, it can be assumed that the enhanced description of the shear velocity results in better understanding of the whole velocity field under breaking waves. Therefore, the article brings a new insight into the field and aims to make a discussion about the need to rethink the way of describing the boundary layer flow in the surf zone.

Energy Crisis in Nigerian University System： Implications of Self Auto-generation for Human Capital Development

Energy requirements for tertiary educational purpose is burgeoning, a reflection of its criticality to human asset formation and to use self auto-generation by petrol or diesel generators as the energy supply source is an unsustainable practice. The situation is worrisome in view of the noise pollution and nuisance that constitutes to the learning environment. This paper, therefore, determines the quantity of self generated energy supply, its intensity, the associated CO2 emissions and their possible implications for human capital development. A survey of generating sets was conducted using the University of Nigeria Nsukka as a representative of Nigerian universities. A walk-through-approach was adopted in gathering data and two metrics-life cycle cost and cost of electricity from auto-generation were used to determine the economic implications of the self generation. The results show that self auto-generation contributed installed energy capacity of amount 19 MVA, 20 MVA, 34 MVA, 11 MVA and 22 MVA to run human capital development activities, respectively for academic sessions from July 2006 to November 2010. The study helps us understand that reforms in educational sector are not effective as long as energy insecurity is a dominant factor.

Life Cycle Input-Output Analysis Extended to Use, Disposal, and Recycling Stages Applied to Embodied CO2 Emissions of a Refrigerator

Input-output analysis is widely employed to analyze inventories of a product＇s embodied energy and environmental burdens. However, input-output analysis focuses only on the production stage and ignores other life cycle phases. Input-output analysis is not exactly a LCA （life cycle assessment） method in the strict sense of ISO 14040 standards, which must cover all stages of a product＇s life cycle, ＂from the cradle to the grave＂, so to speak. A tiered hybrid LCA is a useful tool that covers all life cycle stages by combining a process analysis with the input-output analysis method. This study aims to extend input-output analysis to the use, disposal, and recycling stages by using matrix-based method. The new method is applied to the analysis of the embodied CO2 emissions of a refrigerator as a case study. The entire life cycle C02 emissions are estimated to be 2.9 tons, including indirect emissions, and the reduction in CO2 emissions due to recycling steel scrap is calculated as 48.5 kg. The authors conclude that the new method enables a consistent inventory analysis for all life cycle stages by combining process and input-output methods.

A CONTROL ALGORITHM FOR RAPID MOVEMENTS NEAR THE RADIUS COMPENSATION SINGULARITY IN FIVE-AXIS END MILLING

When the five-axis CNC system executes the 3D cutter radius compensation function,the angle between two adjacent radius compensation vectors might become very large and the linear axes would move too fast if the tool orientation vector is close to the surface normal.The reason that results in this phenomenon is analyzed based on building the transmission relationship between the cutter contact point and the cutter location point.By taking the square-end tool as an example,an optimization algorithm to control the undesired movements is advanced.For the singular area where sudden change exists,the number of interpolation cycles is determined by the cutter feedrate,the limit speeds of machine axes and the maximum allowable angle between radius compensation vectors of adjacent NC blocks.The radius compensation vector of each interpolation cycle is obtained by a kind of vector rotation method.By maintaining the perpendicularity between the radius compensation vector and the tool orientation vector,the rapid movements of the linear axes are eliminated.A trial-cut experiment is performed to verify the correctness and the effectiveness of the proposed algorithm.

Sodium guide star laser generation by single-pass frequency doubling in a periodically poled near-stoichiometric LiTaO_3 crystal

We report in this work a continuous wave(CW) narrowband 589 nm light generation for the purpose of laser guide assisted adaptive optics.A 39 mm long 1 mm thick periodically poled near stoichiometric LiTaO3 crystal with duty cycle near 50% was fabricated using electrical poling at room temperature and pumped by a Raman fiber amplifier.We tested two temperature control ovens,and a maximum conversion efficiency of about 14.3%,corresponding to 4 W of yellow light with 28 W of fundamental power,and bandwidth less than 0.18 GHz was achieved.

Performance analysis for power generating system by using matrix method

We verified that the matrix method, a process analysis method used mainly for life cycle inventory analysis, has several advantages in the analysis of power systems, which have recently become more complex to enhance efficiency and to reduce C02 emissions. While designing a conceptual thermodynamic model of a complex power system, the matrix method provides a definite procedure and facilitates calculations, even if there is a recttrsive loop between the upstream and downstream processes. Similarly, in the case of partial modification to the constructed model, the matrix method can potentially reduce the time and effort required to calculate the thermodynamic balances, even if the constructed model is designed by others. In this study, we obtained mass flow and energy balances of example model power systems by the matrix method from the common thermodynamic conditions including temperatures and pressures which are set on the basis of an existing industrial steam power system. While analyzing the environmental impact of complex multiproduct power systems, such as carbon emissions, the matrix method can be used to easily derive the environmental impact of each final product. We could verify the efficacy of the matrix method in accurately deriving that of an example model power system.

Quasi-periodic variations of low energy cosmic rays

Cosmic rays(CR)play an important role in space weather-related studies.Their temporal variability,both of a quasi-periodic character as well as an irregular one,has been studied from ground-based direct measurements,as well as from cosmogenic nuclides,over a long time.We attempt to describe the current knowledge of selected quasi-periodicities in CR flux in the energy range above the atmospheric threshold,from direct measurements.The power spectrum density(PSD)of the CR time series as measured by neutron monitors(NMs)and by muon detectors has a rather complicated character.Along with the shape(slope)of the PSD,knowledge of the contribution of quasi-periodic variations(q-per)to the CR signal is of importance for the modulation,as well as for checking the links of CR to space weather,and/or to space climate effects.The rotation of the Earth and solar rotation cause two types of mechanisms behind the certain q-per observed in secondary CR on the Earth’s surface.Solar activity and solar magnetic field cyclicities contribute to the q-per signals in CR if studied over a longer time.The complexity of the spatial structure of the interplanetary magnetic field(IMF)and its evolution within the heliosphere,in addition to the changes in the geomagnetic field,cause variability in contributions of the q-per in CR.Wavelet spectra are useful tools for checking the fine structure of q-per and their temporal behaviour.Over a long time NMs and muon telescopes provide information about q-per in CR.