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Lithium niobate is a crystal with excellent electric-optic and nonlinear optical properties. Double-doped and multi-doped lithium niobate are widely used in a wide variety of optical devices. A series of Zn:Ru:Fe:LiNbO3 crystals with different lithium-niobium molar ([Li]/[Nb]) ratios were grown by the Czochralski method. The structures of the crystals with different [Li]/[Nb] ratios are analyzed using X-ray diffraction patterns and infrared spectra. The effect of the [Li]/[Nb] ratio dependence of the doped element concentration and segregation coefficient was studied using an inductive coupled plasma-atomic emission spectrometer (ICP-AES). It was found that the doping elements do not change the crystal structure, and the change of the [Li]/[Nb] ratio will affect the concentration and the occupancy of the doped ions in the crystal. The segregation coefficient and defect structures can be controlled by different [Li]/[Nb] ratios in Zn:Ru:Fe:LiNbO3 crystal.

Zhangye City is a representative agricultural city in China where agriculture depends heavily on precipitation in the Heihe River Basin; water use for agriculture plays a key role in the sustainable development of total water resources. This study, based on the predicted surface runoff by GCM, uses a CGE model with a water-land resources account, to analyze the impact of climate change on Zhangye City’s economy and agricultural water consumption. The results show that climate change increases surface runoff by 8.84%. The increasing surface runoff contributes most to the total water consumption, increasing by 8.11% accompanied by a small GDP expansion of 0.12%. Relative to the industrial structure, agricultural sectors benefit most. Contrarily, export-oriented industrial sectors see a decrease in benefit, resulting in employment migrating to lower value-added agricultural sectors. From the water types, the consumption for underground and other water also rise by 6.69% and 5.73% respectively, due to the economic scale expansion effect of the agricultural sectors. For varieties of crops, grain crops consume more water because of its greater water intensity. And the land is mostly transferred from economic crops to grain crops. Therefore, the government should pay attention to changes in the consumption propensity of water resources, continue to promote agricultural water-saving measures and the adjustment of agricultural planting structure.

Climate change would pose a direct and severe challenge to China's rice production and self-sufficiency. Here we use Global Trade Analysis Project (GTAP) model to evaluate the impacts of climate change on the self-sufficiency of rice in China due to 2 °C rise in temperature, and further analyze the impact and transmission mechanisms of climate change through market and trade. Our simulation method switches different regional mechanisms in the GTAP model by employing alternative closures and scenarios. Our results suggest that the fluctuation in rice price is much larger than that of rice production. The active regional feedback mechanism has much larger effects than the passive one in assessing climate change impacts. With the passive regional feedback mechanism (Single Regional General Equilibrium, SRGE and Multi-Regional General Equilibrium with China's shock, MRGE_C), China's rice export would decrease by more than 8%, and import would increase by over 5%, which leads to a decrease in rice self-sufficiency by more than 0.06 percentage points. With the active regional feedback mechanism (Multi-Regional General Equilibrium with global shock, MRGE_W), climate change will increase China's rice export by 2.7% as rising rice exports to South Korea overweight the export decrease to other countries, concurrently, China's rice import would decrease by 0.04%, which leads to a slight increase in rice self-sufficiency. As a whole, climate change will not severely threaten China's rice self-sufficiency. By the decomposition analysis, climate change impacts on China's rice self-sufficiency mainly depend on the changes in China's domestic rice production. Interestingly, the source of China's rice import will switch from Vietnam to Pakistan under MRGE_W, which derives from the input structure of paddy rice and rice sectors in different countries.

Recent studies have proved that CNN (Convolution neural network) is an effective method to solve steganalysis problem. In this paper, we analyze the influence of the input data sequence on CNN training results according to the training mechanism of CNN. The differences made by variant data sequence may be caused by data correlation, data mini-batch processing and high-pass filtering operations. In experiment, the accuracy of CNN detection with variant data sequence was compared, with cover and stego produced by two steganography algorithms (S_UNIWARD, WOW) with different embedding rates (0.1, 0.4). Results demonstrate that the network detection effect of pairwise data is better than that of random one.

In order to achieve China&rsquo, s target of carbon intensity emissions reduction in 2030, there is a need to identify a scientific pathway and feasible strategies. In this study, we used stochastic frontier analysis method of energy efficiency, incorporating energy structure, economic structure, human capital, capital stock and potential energy efficiency to identify an efficient pathway for achieving emissions reduction target. We set up 96 scenarios including single factor scenarios and multi-factors combination scenarios for the simulation. The effects of each scenario on achieving the carbon intensity reduction target are then evaluated. It is found that: (1) Potential energy efficiency has the greatest contribution to the carbon intensity emissions reduction target, (2) they are unlikely to reach the 2030 carbon intensity reduction target of 60% by only optimizing a single factor, (3) in order to achieve the 2030 target, several aspects have to be adjusted: the fossil fuel ratio must be lower than 80%, and its average growth rate must be decreased by 2.2%, the service sector ratio in GDP must be higher than 58.3%, while the growth rate of non-service sectors must be lowered by 2.4%, and both human capital and capital stock must achieve and maintain a stable growth rate and a 1% increase annually in energy efficiency. Finally, the specific recommendations of this research were discussed, including constantly improved energy efficiency, the upgrading of China&rsquo, s industrial structure must be accelerated, emissions reduction must be done at the root of energy sources, multi-level input mechanisms in overall levels of education and training to cultivate the human capital stock must be established, investment in emerging equipment and accelerate the closure of backward production capacity to accumulate capital stock.

In order to preserve the statistical properties of information hiding when embedding changes are constrained to pixels, a color image steganography method is proposed based on FLD Ensemble classifiers and content-adaptive quadtree algorithm. First, the color cover is divided into several non-overlapping sub-blocks by quad-tree algorithm, and each block is prioritized depending on its texture complexity. Then, we extract the statistical feature of blocks with high priority from three channels respectively. Then, we use such feature as the input of FLD Ensemble classifiers, which are trained by color stego images generated by the current steganography schemes LSBM, WOW and S-UNIWARD. Then, we design the additive distortion function of color images and the pixel distortion is computed by results of the Ensemble classifiers. We use STC embed secret message into R, B, G channels respectively. The experimental results show that the proposed scheme can achieve a competitive performance compared with the other steganography schemes LSBM, WOW and S-UNIWARD when resisting SPAM steganalysis methods for color images effectively.

A series of Hf:Dy:LiNbO3 crystals with various [Li]/[Nb] ratios ([Li]/[Nb]=0.946, 1.05, 1.20 and 1.38) in the melt were grown by the Czochralski method. The UV-VIS-NIR absorption spectra of Hf:Dy:LiNbO3 crystals were measured, and Judd-Ofelt (J-O) theory is used to evaluate the transition intensity parameters Ω2, 4, 6 and spectroscopic quality factor (X). The X of Hf:Dy:LiNbO3 crystals with the [Li]/[Nb] ratio of 1.38 was found to be 2.11. The up-conversion luminescence at around 475 nm, 582 nm, 653 nm and 749 nm of Dy3+ ions were observed under 800 nm excitation. The energy transfer mechanisms of up-conversion process were analyzed in detail, and luminescence lifetime was measured. The results show that Hf:Dy:LiNbO3 crystal is an excellent candidate for laser medium.

Enterprises always have to pursue for profitability while maintaining long term competitive advantages. Today, this task becomes more challenging due to globalization and dynamic changing business environment. For each enterprise, this task can not be fulfilled without changes to its business infrastructure and IT systems. That is, enterprises need to transform themselves to adapt to both external and internal changes. This kind of transformation is not simply any transactional act, but rather a never-easy journey. In this paper, the concept of continual business transformation is introduced with key challenges identified. Based on experience from practical cases, we propose a set of business transformation technology framework that incorporates component-based approach and business-driven architecture. In the framework, CBM (Component Business Modeling) method is to identify transformation opportunities and provide guidance to IT architecture design from business perspectives. As transformation needs to be conducted in a holistic view, IT Blueprint in the framework is to provide an enterprise-wide IT design and governance model. To avoid building more silo applications as happening today in many cases, the IT Blueprint can be used to guide solution development for better alignment among different applications as well as across various stages during the transformation. Another keystone in the framework is Assetization, which is proposed for quality improvement and cost reduction from harvesting and reusing artifacts built in the transformation journey. Furthermore, we also illustrate how these methods and technologies were validated in a transformation engagement with a leading international bank in Asia-Pacific with satisfactory results.

In this paper, a manageable Web services hub framework and enabling technologies for e-sourcing are proposed for buyers, suppliers, service providers and trading partners to register business, user and service information as well as to provision and subscribe to services. The proposed framework enables a business to dynamically configure its business processes to integrate with existing Web services provided by other enterprises based on service requirements. Next, a multi-level security mechanism ensuring secure communications in a hub or among hubs is presented. An advanced Web services discovery mechanism is introduced after that for looking up multiple UDDI registries and aggregating results in an efficient manner. A working system of this framework, Managed e-Hub, which provides an infrastructure for enabling next generation e-utilities in a secure and controlled environment, is also presented in this paper. Some further research ideas are given at the end of the paper.

Software development is exhibiting some noticeable characteristics: model-based development, team work, parallel development, incremental and iterative development, transregional development and so on. The development process is becomes so complicated that a CASE environment is requested to support some mechanisms: mass tool integration, staff cooperation, process management, extensive data sharing, data management etc. So, along with mass, cooperating integrative development tools, a management environment with the ability to accomplish the above-mentioned tasks is also in great demand. UML (Unified Modeling language) is one of the latest achievements in the field of software engineering. Based on the experience of process engineering, the authors are constructing a development and management environment supporting UML. They discuss in detail how this environment effectively supports the object-oriented (OO) development process based on UML, and how this environment satisfies the characteristics listed above. They devote themselves to solving problems in process management and the collaboration on data.