基于快速DCT的画面内块的空域内插

主要介绍对边界像素进行约束来恢复画面中块的方法。这种方法基本假设前提是如果对块中丢失和它的边界像素进行DCT变换,含高频成分系数归化为零,这样就可以得到一系列线性方程,通过对这些方程求解就可以求出丢失的像素的近似值。这种方法只需对八个边界像素进行运算。

基于离散余弦变换域的块相关性和马尔可夫模型的图像隐写分析

提出高阶统计方法检测JPEG图像隐写.为充分描述图像数据及它们空间位置的相关性,运用了JPEG块内、块间系数间的相关性.使用量化分块DCT系数绝对值之差生成水平、垂直和zigzag方向的块内、块间差分数组,采用马尔可夫过程模拟差分数组,提取二阶统计量——差分数组转移概率矩阵——为隐写分析特征向量.仿真结果证明本文提出的方法的检出率高于已知方法的检出率.

帧内微块复制的屏幕图像编码算法

针对现有的帧内块复制(IBC)算法不能很好地适应屏幕图像具有各种不同大小和形状样图的问题,为了进一步提高屏幕图像的编码效率,提出了一种帧内微块复制(IMBC)算法。该算法首先将当前编码单元(CU)划分成L个微块。然后以每个微块作为最小的匹配和复制单元,采用匹配微块组选择算法,在参考像素集合R中找到与当前微块最匹配的"参考微块"。用L个位移矢量(DV)来表示"参考微块"所在位置与当前CU所在位置的位移关系。最后,对L个位移矢量应用预测算法以消除位移矢量之间的相关性后进行熵编码。对于屏幕图像标准测试数据集合中的视频序列,IMBC算法与IBC算法相比,在编码复杂度增加较低的前提下,在全帧内(AI)、随机接入(RA)、低延迟(LB)三种编码配置中,有损BD-rate降低率分别达3.4%、2.9%、2.6%,无损Bit-rate降低率分别达9.5%、5.2%、5.1%,能有效提高屏幕图像的编码效率。

定宽压力机内外块受力分析与在线测试

首先采用有限元软件对走停式定宽压力机内、外块的应力状态进行了定量分析,得到了内、外块最大应力随时间的变化关系,确定了内、外块的应力集中部位,然后对内、外块应力状态进行了在线测试,在5个不同的测试点的有限元模拟结果与实测结果均吻合良好,验证了有限元模型的正确性,为内、外块结构设计与优化提供了重要的理论依据。

SECCL-based research on prefabricated chunks in achieving oral English fluency

Fluency on oral English has always been the goal of Chinese English learners. Language corpuses offer great convenience to language researches. Prefabricated chunks are a great help for learners to achieve oral English fluency. With the help of computer software, chunks in SECCL are categorized. The conclusion is in the process of chunks acquiring, emphasis should be on content-related chunks, especially specific topic-related ones. One effective way to gain topic-related chunks is to build topic-related English corpus of native speakers.

Critical Approach to Methods of Glacier Reconstruction in High Asia and Discussion of the Probability of a Qinghai-Xizang (Tibetan) Inland Ice

This overview discusses old and new results as to the controversy on the past glacier extension in High Asia, which has been debated for 35 years now. This paper makes an attempt to come closer to a solution. H.v. Wissmann's interpretation (1959) of a small-scale glaciation contrasts with M. Kuhle's reconstruction (1974) of a large-scale glaciation with a 2.4 million km2 extended Qinghai-Xizang (Tibetan) inland glaciation and a Himalaya-Karakorum icestream network. Both opinions find support but also contradiction in the International and Chinese literature (Academia Sinica). The solution of this question is of supraregional importance because of the subtropical position of the concerned areas. In case of large albedo-intensive ice surfaces, a global cooling would be the energetical consequence and, furthermore, a breakdown of the summer monsoon. The current and interglacial heat-low above the very effective heating panel of the Qinghai-Xizang (Tibetan) Plateau exceeding 4000 m, which gives rise to this monsoon circulation, would be replaced by the cold-high of an inland ice. In addition, the plate-tectonically created Pleistocene history of the uplift of High Asia — should the occasion arise up to beyond the snowline (ELA) —would attain a paleoclimatically great, perhaps global importance. In case of a heavy superimposed ice load, the question would come up as to the glacio-isostatic interruption of this primary uplift. The production of the loesses sedimentated in NE-China and their very probable glacial genesis as well as an eustatic lowering of the sea-level by 5 to 7 m in the maximum case of glaciation are immediately tied up with the question of glaciation we want to discuss. Not the least, the problems of biotopes of the sanctuary-centres of flora and fauna, i.e., interglacial re-settlement, are also dependent on it. On the basis of this Quaternary- geomorphological-glaciological connection, future contributions are requested on the past glaciation, the current and glacial permafrost table and periglacial development, the history of uplift, and the development of Ice Age lakes and loess, but also on the development of vegetation and fauna in High Asia.

Macro Perspective of Industry 4.0： Factors Affecting Value Creation Modules

Business needs to manage such a variety of things inside the firm or outside the business consistently. This factor affects the business in various ways. The factor which affects the business is clients, suppliers, distributors and so on. These all components are isolated from two sections full-scale environment and miniaturized scale environment. Macro perspective environment components are those external variables which are past the association＇s control. The problem of this study is guaranteeing a supportable evolvement of human presence in its social, ecological, and monetary measurement. So, we have to adapt test in order to outfit toward manageability. As for the method used in this study, it depends on using empirical framework to meet the interest of capital and buyer, in addition to supporting human presence in its social, ecological, monetary measurement. The paper is organised as following sections： first section is the introduction, second section is the literature review, the third section includes the research method, fourth one discusses the analysis, while the conclusion is in the fifth section.

Design and Implementation of a 3D Ocean Virtual Reality and Visualization Engine

In this study,a 3D virtual reality and visualization engine for rendering the ocean,named VV-Ocean,is designed for marine applications.The design goals of VV-Ocean aim at high fidelity simulation of ocean environment,visualization of massive and multidimensional marine data,and imitation of marine lives.VV-Ocean is composed of five modules,i.e.memory management module,resources management module,scene management module,rendering process management module and interaction management module.There are three core functions in VV-Ocean:reconstructing vivid virtual ocean scenes,visualizing real data dynamically in real time,imitating and simulating marine lives intuitively.Based on VV-Ocean,we establish a sea-land integration platform which can reproduce drifting and diffusion processes of oil spilling from sea bottom to surface.Environment factors such as ocean current and wind field have been considered in this simulation.On this platform oil spilling process can be abstracted as movements of abundant oil particles.The result shows that oil particles blend with water well and the platform meets the requirement for real-time and interactive rendering.VV-Ocean can be widely used in ocean applications such as demonstrating marine operations,facilitating maritime communications,developing ocean games,reducing marine hazards,forecasting the weather over oceans,serving marine tourism,and so on.Finally,further technological improvements of VV-Ocean are discussed.

OPKH: A Lightweight Online Approach to Protecting Kernel Hooks in Kernel Modules

Kernel hooks are very important con- trol data in OS kernel. Once these data are com- promised by attackers, they can change the control flow of OS kemel＇s execution. Previ- ous solutions suffer from limitations in that： 1） some methods require modifying the source code of OS kernel and kernel modules, which is less practical for wide deployment; 2） other methods cannot well protect the kernel hooks and function return addresses inside kernel mo- dules whose memory locations cannot be pre- determined. To address these problems, we propose OPKH, an on-the-fly hook protection system based on the virtualization technology. Compared with previous solutions, OPKH off- ers the protected OS a fully transparent envi- ronment and an easy deployment. In general, the working procedure of OPKH can be di- vided into two steps. First, we utilise the me- mory virtualization for offiine profiling so that the dynamic hooks can be identified. Second, we exploit the online patching technique to in- strument the hooks for run-time protection. The experiments show that our system can pro- tect the dynamic hooks effectively with mini- mal performance overhead.

In-Pipe Mobile Minimachine and Its Control

This paper deals with utilization possibility of a kinematical couple of screw-matrix in minimachine mechatronic concept which is assigned to move within the pipes having less than 25 mm of the inner diameter. The principle of the movement for a straightforward motion consists in transformation of the actuator rotary movement through a screw and a nut to the linear motion. It causes a change of distance between the front and rear parts of the minimachine modules. Due to minimization of the dimensions, the electrical control and power supply components are placed outside of the minimachine operating area. The control module is based on a programmable integrated circuit （PIC）.

A Practical Online Approach to Protecting Kernel Heap Buffers in Kernel Modules

Heap overflow attack is one of the major memory corruption attacks that have become prevalent for decades. To defeat this attack,many protection methods are proposed in recent years. However,most of these existing methods focus on user-level heap overflow detection. Only a few methods are proposed for kernel heap protection. Moreover,all these kernel protection methods need modifying the existing OS kernel so that they may not be adopted in practice. To address this problem,we propose a lightweight virtualization-based solution that can protect the kernel heap buffers allocated for the target kernel modules. The key idea of our approach is to combine the static binary analysis and virtualization technology to trap a memory allocation operation of the target kernel module,and then add one secure canary word to the end of the allocated buffer. After that,a monitor process is launched to check the integrity of the canaries. The evaluations show that our system can detect kernel heap overflow attacks effectively with minimal performance cost.

Intravascular Ultrasound Image Hard Plaque Recognition and Media-adventitia Border Detection

Intravascular ultrasound (IVUS) is a new technology for the diagnosis of coronary artery disease, and for the support of coronary intervention. IVUS image segmentation often encounters difficulties when plaque and acoustic shadow are present A novel approach for hard plaque recognition and media-adventitia border detection of IVUS images is presented in this paper. The IVUS images were first enhanced by a spatial-frequency domain filter that was constructed by the directional filter and histogram equalization. Then, the hard plaque was recognized based on the intensity variation within different regions that were obtained using the k-means algorithm. In the next step, a cost matrix representing the probability of the media-adventitia border was generated by combining image gradient, plaque location and image intensity. A heuristic graph-searching was applied to find the media-adventitia border from the cost matrix.Experiment results showed that the accuracy of hard plaque recognition and media-adventitia border detection was 89.94% and 95.57%, respectively. In conclusion,using hard plaques recognition could improve media-adventitia border detection in IVUS images.

Texture Analysis and Characteristic Identification About Plaque Tissues of IVUS

Intravascular ultrasound can provide clear real-time cross-sectional images,including lumen and plaque.In practice,to identify the plaques tissues in different pathological changes is very important.However,the grayscale differences of them are not so apparent.In this paper a new textural characteristic space vector was formed by the combination of Co-occurrence Matrix and fraction methods.The vector was projected to the new characteristic space after multiplied by a projective matrix which can best classify those plaques according to the Fisher linear discriminant.Then the classification was completed in the new vector space.Experimental results found that the veracity of this classification could reach up to 88%,which would be an accessorial tool for doctors to identify each plaque.

A Discussion on Correlations of Plate Motion with Seismic Anisotropy and Stress Field in Plate Boundary Zones

In many parts of the global plates,including subduction zones,mid-ocean ridges and even the interior of the continental plates,seismic anisotropy has a certain correlation with image of absolute plate motion( APM),or is in accord with the predominant direction of the intraplate stress field. In our study,a statistical analysis is done on the correlations of plate motion with seismic anisotropy as well as a stress field within nine plate boundaries which contain major subduction zones in the globe. Results indicate that absolute or relative plate motion( RPM) controls the seismic anisotropy and stress field of the plate boundary,which is especially obvious for the RPM. It can also be inferred that the correlation of RPM is better than that of APM. Because of the complexity of subduction mechanism and diversity of controlling factors at plate boundaries containing subduction zones,the correlation becomes much complex. Sources of anisotropy at various depths show different characteristics,and stress state is controlled by many factors,thus further discussions on the correlations are required.

Biogeographic characteristics of Zhesi brachiopod fauna and reconstruction of tectonopaleogeography of Jiamusi-Mongolia Block

The Kungurian-Capitanian （Permian） Zhesi branchiopod fauna is mainly composed of cold-water typed taxa with high diversity and abundance. This fauna is similar with the coeval brachiopod faunas from Ti- man-Pechora, Svalbard, and Queen Elizabeth Islands of the Boreal Realm, with no real ＂warm-water＂ species. Zhesi brachiopod fauna is a cold-water fauna and should be assigned to the Boreal Realm. Considering the paleogeographic characteristics of this fauna and the basic rationale of paleobiogeographie provinces being controlled by latitude-temperate, and that the above areas were located at 50°N -70°N in the global paleoclimate reconstruction map compiled by Boucot et al. , the paleo-latitude of the southern margin of Jiamusi-Mongolia Block, where developed the Zhesi brachiopod fauna, is suggested ranging from 40°N to 60°N. Zhesi brachiopod fauna is an endemic fauna, containing more than 75% endemic species and self-grouped as a biogeographic province, termed Inner Mongolia Province. These characteristics indicate that this area was closed or semiclosed at that time. On the Jiamusi-Mongolia Block, the Herlen-Jiamusi Old-land as an obvious ＂continental barrier＂ hindered the northward migration of the Zhesi brachiopod fauna and the immigration of brachiopod species from other areas. The Tarim plate has collided with the Kazakhstan plate and the western part of South Tianshan-Beishan-Xar Moron Ocean has been closed. At the same time, the western margin of Jiamusi-Mongolia Block was joined with the Tarim plate. The Xar Moron Ocean in south of Jiamusi-Mongolia Block was wide e- nough and the ocean temperature rose gradually southward, so that it is not suitable for the cold-water brachiopods to survive and thrive on the northern margin of the North China plate. Thus, the ocean with large width and high temperature formed another natural barrier for the southward migration of the cold-water brachiopods.

The Active Yakutat （Kula？） Plate and Its Southcentral Alaska Megathrust and Intraplate Earthquakes

Alaska geology and plate tectonics have not been well understood due to an active Yakutat plate, believed to be part of the remains of an ancient Kula plate, not being acknowledged to exist in Alaska. It is positioned throughout most of southcentral Alaska beneath the North American plate and above the NNW subducting Pacific plate. The Kula？ plate and its eastern spreading ridge were partially ＂captured＂ by the North American plate in the Paleocene. Between 63 Ma and 32 Ma, large volumes of volcanics erupted from its subducted N-S striking spreading ridge through a slab window. The eruptions stopped at 32 Ma, likely due to the Pacific plate fiat-slab subducting from the south beneath this spreading ridge. At 28 Ma, magmatism started again to the east; indicating a major shift to the east of this ＂refusing to die＂ spreading ridge. The captured Yakutat plate has also been subducting since 63 Ma to the WSW. It started to change to WSW fiat-slab subduction at 32 Ma, which stopped all subduction magmatism in W and SW Alaska by 22 Ma. The Yakutat plate subduction has again increased with the impact/joining of the coastal Yakutat terrane from the ESE about 5 Ma, resulting in the Cook Inlet Quaternary volcanism of southcentral Alaska. During the 1964 Alaska earthquake, sudden movements along the southcentral Alaska thrust faults between the Yakutat plate and the Pacific plate occurred. Specifically, the movements consisted of the Pacific plate moving NNW under the buried Yakutat plate and of the coastal Yakutat terrane, which is considered part of the Yakutat plate, thrusting WSW onto the Pacific plate. These were the two main sources of energy release for the E part of this earthquake. Only limited movement between the Yakutat plate and the North American plate occurred during this 1964 earthquake event. Buried paleopeat age dates indicate the thrust boundary between the Yakutat plate and North American plate will move in about 230 years, resulting in a more ＂continental＂ type megathrust earthquake for southcentral Alaska. There are, therefore, at least two different types ofmegathrust earthquakes occurring in southcentral Alaska： the more oceanic 1964 type and the more continental type. In addition, large ＂active＂ WSW oriented strike-slip faults are recognized in the Yakutat plate, called slice faults, which represent another earthquake hazard for the region. These slice faults also indicate important oil/gas and mineral resource locations.

Study on the Scaffolding Teaching of Three-dimensional Animation Foundation based on Modularization

In this paper, the teaching of course Three-dimensional Animation Foundation is designed mainly based on teaching content modularization and scaffolding teaching model. The modularized content design for Three-dimensional Animation Foundation is specifically expounded, and also the ideas for developing the scaffolding teaching model are analyzed. How to integrate the scaffolding teaching model into course teaching is introduced in details. Finally, new methods for guiding students to think independently in course teaching and improve students＇ self-awareness and self-learning ability are proposed.

Feasibility of diagnosing unstable plaque in patients with acute coronary syndrome using iMap-IVUS

Objective： To compare the plaque composition between stable and unstable plaques, characterize unstable plaque by using iMap-intravascular ultrasound （IVUS）, and quantify the diagnostic criteria for unstable plaque. Methods： Thirty-three acute coronary syndrome （ACS） patients who had undergone coronary angiography and IVUS from February 19, 2014 to December 19, 2014 at Peking University People＇s Hospital were enrolled in the study. Baseline data were collected. The patients were divided into two groups according to their gray-scale IVUS imaging, stable plaque and unstable plaque. A difference-in-difference evaluation was performed using the baseline data and off-line iMap imaging results between the two groups. A receiver operating characteristic （ROC） curve was constructed to obtain the optimal cut-off value to diagnose unstable plaque. Results： Percentages of fibrotic and necrotic tissues, absolute values of lipidic, necrotic, and calcified tissues, and plaque burden were independent predictors for unstable plaque. Absolute necrotic area was the best predictor and exhibited the highest diagnostic value for plaque vulnerability （area under the curve （AUC）=0.806, P=0.000, 95% CI （0.718, 0.894））. The cut-off score for predicting unstable plaque was 4.0 mm2. Conclusions： This study attempted to propose a cut-off value based on absolute necrotic area using iMap-IVUS to predict plaque vulnerability in patients with ACS. This score might provide a valuable reference for diagnosing unstable plaque.

Enhanced External Counterpulsation Treatment Inhibitting Advanced Atherosclerotic Plaque Progression by Augmenting the Plaque Wall Stress： An in vivo FSI Study Based on Animal Experiment

Enhance extemal counterpulsation （ECP） procedure has exhbited itself to be an effective therapy for the m anagem entof ischem ic card iovascu lar diseases, However, considering that EECP significantly increases the acute diastolic pressure, whether it will intervene in the chronic progression of advanced plaque causing great concern in clilical applkation, but yet rein ains elusive presently. In the current paper, a flu id-structure interface （FSI） num erical model of artery with p iaque corn ponent w as developed based on in vivo hem odynam ic m easurem entperfotm ed h a porcine model, to caku late the m echanical stresses of the plaque before and during EECP, and h lum to assess the potential effects of long-term EECP treatm ent on plaque progression. The resu Its show that E E C P augm ented the wall shear stress （WSS） and plaque w all stress （PWS） over the card lac cycles, aswell as the spacial oscillatory of W SS （WSSG ）. Durhg EECP treatm ent, the PW S level respectively raised 6.82% and 6.07% in two simulation cases. The currentpilot study suggests that E E C P treatm entre ay p lay a positive effect on inh biting the conthued plaque progression by hcreashg the PW S level over the card iac cycles. Meanwhile, the plaque morphology should be taken into consideration while m aking patient- specific plan for Ion g- term E E C P treatment in clinic.

Relative T-Injective Modules and Relative T-Flat Modules

Abstract Let T be a Wakamatsu tilting module. A module M is called （n, T）-copure injective （resp. （n, T）-copure flat） if εT^1（N, M） = 0 （resp. Г1^T（N, M） = 0） for any module N with T-injective dimension at most n （see Definition 2.2）. In this paper, it is shown that M is （n, T）-copure injective if and only if M is the kernel of an In（T）-precover f ： A → B with A ∈ ProdT. Also, some results on Prod T-syzygies are presented. For instance, it is shown that every nth Prod T-syzygy of every module, generated by T, is （n, T）-copure injective.