Probabilistic Global Maximum Power Point Tracking Algorithm for Continuously Varying Partial Shading Conditions on Autonomous PV Systems

A photovoltaic (PV) string with multiple modules with bypass diodes frequently deployed on a variety of autonomous PV systems may present multiple power peaks under uneven shading. For optimal solar harvesting, there is a need for a control schema to force the PV string to operate at global maximum power point (GMPP). While a lot of tracking methods have been proposed in the literature, they are usually complex and do not fully take advantage of the available characteristics of the PV array. This work highlights how the voltage at operating point and the forward voltage of the bypass diode are considered to design a global maximum power point tracking (GMPPT) algorithm with a very limited global search phase called Fast GMPPT. This algorithm successfully tracks GMPP between 94% and 98% of the time under a theoretical evaluation. It is then compared against Perturb and Observe, Deterministic Particle Swarm Optimization, and Grey Wolf Optimization under a sequence of irradiance steps as well as a power-over-voltage characteristics profile that mimics the electrical characteristics of a PV string under varying partial shading conditions. Overall, the simulation with the sequence of irradiance steps shows that while Fast GMPPT does not have the best convergence time, it has an excellent convergence rate as well as causes the least amount of power loss during the global search phase. Experimental test under varying partial shading conditions shows that while the GMPPT proposal is simple and lightweight, it is very performant under a wide range of dynamically varying partial shading conditions and boasts the best energy efficiency (94.74%) out of the 4 tested algorithms.

GLOBAL ASYMPTOTIC STABILITY IN N-SPECIES NONAUTONOMOUS LOTKA-VOLTERRACOMPETITIVE SYSTEMS WITH DELAYS

A delayed n-species nonautonomous Lotka-Volterra type competitive system without dominating instantaneous negative feedback is investigated. By means of a suitable Lyapunov functional, sufficient conditions are derived for the global asymptotic stability of the positive solutions of the system. As a corollary, it is shown that the global asymptotic stability of the positive solution is maintained provided that the delayed negative feedbacks dominate other interspecific interaction effects with delays and the delays are sufficiently small.

Cotidal charts and tidal power input atlases of the global ocean from TOPEX/Poseidon and JASON-1 altimetry

The global distributions of eight principal tidal constituents, M2, S2, K1, O1, N2, K2, P1, and Q1, are derived using TOPEX/Poseidon and JASON-1（T/P-J） satellite altimeter data for 16 a. The intercomparison of the derived harmonics at 7000 subsatellite track crossover points shows that the root mean square （RMS） values of the tidal height differences of the above eight constituents range from 1.19 cm to 2.67 cm, with an average of about 2 cm. The RMS values of the tidal height differences between T/P-J solutions and the harmonics from ground measurements at 152 tidal gauge stations for the above constituents range from 0.34 cm to 1.08 cm, and the relative deviations range from 0.031 to 0.211. The root sum square of the RMS differences of these eight constituents is 2.12 cm, showing the improvement of the present model over the existing global ocean tidal models. Based on the obtained tidal model the global ocean tidal energetics is studied and the global distribution of the tidal power input density by tide-generating force of each constituent is calculated, showing that the power input source regions of semidiurnal tides are mainly concentrated in the tropical belt between 30S and 30N, while the power input source regions of diurnal tides are mainly concentrated off the tropic oceans. The global energy dissipation rates of the M2, S2, K1, O1, N2, P1, K2 and Q1 tides are 2.424, 0.401, 0.334, 0.160, 0.113, 0.035, 0.030 and 0.006 TW, respectively. The total global tidal dissipation rate of these eight constituents amounts to 3.5 TW.

Relationship between urban eco-environment and competitiveness with the background of globalization: Statistical explanation based on industry type newly classified with environment demand and environment pressure

Within the global urban system, the statistical relationship between urban eco-environment(UE) and urban competitiveness(UC)(RUEC) is researched. Data showed that there is a statistically inverted-U relationship between UE and UC. Eco-environmental factor is put into the classification of industries, and gets six industrial types by two indexes viz. industries' eco-environmental demand and pressure. The statistical results showed that there is a strong relationship, for new industrial classification, between the changes of industrial structure and evolvement of UE. The drive mechanism of the evolvement of urban eco-environment, with human demand and global work division was analyzed. The conclusion is that the development stratege, industrial policies of cities, and environmental policies fo cities must be fit with their ranks among the global urban system. At the era of globalization, so far as the environmental policies, their rationality could not be assessed with the level of strictness, but it can enhance cities' competitiveness when they are fit with cities' capabilities to attract and control some sections of the industry's value-chain. None but these kinds of environmental policies can probably enhance the UC.

New results on global exponential stability of competitive neural networks with different time scales and time-varying delays

This paper studies the global exponential stability of competitive neural networks with different time scales and time-varying delays. By using the method of the proper Lyapunov functions and inequality technique, some sufficient conditions are presented for global exponential stability of delay competitive neural networks with different time scales. These conditions obtained have important leading significance in the designs and applications of global exponential stability for competitive neural networks. Finally, an example with its simulation is provided to demonstrate the usefulness of the proposed criteria.

Re-Evaluation of China＇s Service Trade Competitiveness： A Global Value Chain Perspective

Based on the Worm Input-Output Database （WIOD）, this paper conducts a forward-linkage decomposition of value-added in trade to estimate China＇s service value-added exports and its service sector＇s international competitiveness during 2000- 2014. Result indicates that during the sample period, China＇s service exports measured by forward-linkage decomposition method accounted for around 35% in its total export. While the value of services exported directly through the service sector accounted for a falling share, the value of services exported through other sectors represented an increasing share. China ranks second in the world in terms of market share of service exports. However, the revealed comparative advantage （RCA） of China＇s service exports and export sophistication remains limited.

Analysis of the trend of global power sources based on comment emotion mining

In recent years,renewable energy technologies have been developed vigorously,and related supporting policies have been issued.The developmental trend of different energy sources directly affects the future developmental pattern of the energy and power industry.Energy trend research can be quantified through data statistics and model calculations;however,parameter settings and optimization are difficult,and the analysis results sometimes do not reflect objective reality.This paper proposes an energy and power information analysis method based on emotion mining.This method collects energy commentary news and literature reports from many authoritative media around the world and builds a convolutional neural network model and a text analysis model for topic classification and positive/negative emotion evaluation,which helps obtain text evaluation matrixes for all collected texts.Finally,a long-short-term memory model algorithm is employed to predict the future development prospects and market trends for various types of energy based on the analyzed emotions in different time spans.Experimental results indicate that energy trend analysis based on this method is consistent with the real scenario,has good applicability,and can provide a useful reference for the development of energy and power resources and of other industry areas as well.

Impacts of Emerging Biotechnologies on Major Power Competition and Global Governance

COVID-19’s global spread has exposed the weakness of biosecurity systems,underlining shortcomings and increasing the difficulty of global governance.Given the dilemma inherent in biotechnology’s prospects and risks,the leadership of biotechnology and biosecurity capability has become a focal point of great power competition.Both the threat of bioterrorism and the risk of the misuse or abuse of biotechnology are urgent and complicated.Due to the lack of verification mechanisms and the dual-nature of biotechnology,biosecurity competition may result in an arms race or military conflict,but major powers can innovate cooperation mechanisms to provide public goods and manage risk.

Research on key technologies of deduction of multinational power trading in the context of Global Energy Interconnection

When transnationalized electricity trade is conducted in the context of Global Energy Interconnection(GEI),the transaction settlement usually has a long cycle and high cost and is influenced by the volatility of the exchange rate.It is thus necessary to overcome the problems associated with the transaction settlement,change in the trading model data,and trading strategy in the transnational transaction deduction.To overcome the problem of trade settlement,this paper proposes the use of a digital currency(energy currency)for the cross-border electricity trading settlement based on the special drawing rights of the International Monetary Fund,which is controlled by the Global Energy Interconnection Development and Cooperation Organization(GEIDCO),to enable the proposed currency to become a stable digital currency.The traders can use the energy coins as a unit of currency for quotes,combined with the data pertaining to the changes in the energy information obtained from the GEI framework and data regarding the optimally extrapolated reference trading indicators.To realize the implementation of the multi-trader concurrent transaction deduction using a microservice architecture,this paper proposes a method of computing the microservice and synchronous interaction among the traders,based on the database table data,because the large amount of computation is required to be accomplished asynchronously with a single process.The key technology behind these cross-national electricity trading simulations can not only enable the GEI transnational traders to performed daily real-time trading,but it also demonstrates the advantages of the rapid settlement of the energy currency and the realization of a stable payment in the global energy interconnection cross-border electricity trading.

Research on the Competitive Power of the Industrial Clusters in China

Industrial clusters have been an important phenomenon of the global economy. The most important reason for its becoming the focus of people＇s attention and the popular mode of industry programming is continuous and powerful competitiveness ,The article analyzes this competitiveness, and points out some problems of China＇s industrial clusters, which directly affects its current competitiveness and further development. Finally, we propose stone specific measures of those problems.

China's Global Energy Strategy: from Energy Strength to Energy Power

Since the founding of the People's Republic of China in 1949, China's global energy strategy has experienced three stages: "infancy", "growth" and "maturity". Chinese foreign energy cooperation has also gone through three periods chronologically, which include(1) the period when China got rid of its high dependence on oil imports from the Soviet Union, achieved self-reliance and even became a net exporter;(2) the period when China first focused on "bringing in" and then turned itself into a net importer of crude oil and refined oil; and(3) the period when China "went global" to engage in energy cooperation in diverse areas, gradually shifting into a leading role before launching the Belt and Road Initiative, which marked the full establishment of the Chinese global energy strategy. The objective of the Chinese global energy strategy has gradually changed from merely pursuing "energy strength" to transforming "energy strength" into "energy power"; the mission is mainly to "promote energy cooperation and energy revolution"; to implement this mission, China will provide international public goods to global and regional energy governance through energy diplomacy and services; and the areas covered by the strategy are countries and regions along the "Silk Road Economic Belt".

Application of Fuzzy Comprehensive Evaluation to Air-conditioning Competitive Power Analysis

As the conceptual design of air-conditioning is done using the theory of Quality Function Deployment (QFD),cus- tomer requirements should be understood and the product competitive power be analyzed as exactly as possible for new product de- signing.Lots of information in the process of this research is fuzzy and uncertain,but traditional QFD can not deal with it well. Fuzzy theory can solve the problem.So a fuzzy model for analyzing product competitive power is formulated in this paper to im- prove traditional QFD,after that it is applied to analyze air-conditioning competitive power.When air-conditioning competitive power is analyzed using this model,firstly the importance weight of the customer requirements o fair-conditioning is determined us- ing the Analytic Hierarchy Process (AHP) weighting process,then air-conditloning competitive power is evaluated using fuzzy comprehensive evaluation.It is proved that the model is feasible and has good applicability.

The permanence and global attractivity of a competitive system with feedback controls and toxic substance

In this paper,we consider a nonautonomous competitive system with feedback controls and toxic substance.Some average couditions for the permanence and global attractivity of the system are obtained.It is shown that our results are generalization or improvement of those of Zhao,Jiang and Lazer [Nonlinear Analysis:Real World Applications,5(4)(2004),265-276],Xia,Cao,Zhang and Chen [Journal of Mathematical Analysis and Applications,294(2)(2004),503-522] and Chen [Nonlinear Analysis:Real World Applications,in press]

The power of the public purse: financing of global health partnerships and acienda setting for sustainability

Public-private partnerships(PPPs) have reshaped the institutional structure of global governance.They have advanced collaboration on core issues such as health, clean energy, the rights of women and children, and access to infrastructure, among others. But which actors create and finance public-private partnerships in global governance to advance such objectives? What are the implications of the agency behind such collaboration for influencing the global agenda on sustainable development? While some scholars and advocacy groups see the growing role of private actors as a powershift away from public institutions, others argue that such arrangements tend to be complementary to public mandates and indeed may provide a new means for international institutions to pursue such mandates. The article probes this debate by analyzing the type of actors that finance global health partnerships, an area in which the influence of hybrid initiatives is particularly prominent. It reveals that public financing remains a core and necessary condition for the emergence and functioning of PPPs. The growing share of private financing,nonetheless, has important implications for shaping partnerships agendas and steering global health and sustainability governance. Rather than a powershift or abdication of responsibilities by the state, there is rather a tendency of deliberate diffusion of power by donors toward hybrid structures.

Promotion of Agricultural Products Competitive Power in Heilongjiang Province with Modern Logistics

The paper studied the competitive power of agricultural products in Heilongjiang Province by analyzing the revealed comparative advantage,and drew the conclution that agricultural products competitive power was decreasing in Heilongjiang Province.There were three main reasons for this status: firstly,the cost of circulation of agricultural products was increasing;secondly,the commodity rate of agricultural products was low;thirdly,the marketing power of agricultural product was weak because of lacking the ...

Analysis on the Mode and Competitive Strategy of Electricity Sales in the Background of Electric Power System Reform

A new round of reform of the power system conforms to the national development of the energy revolution and the reform of the electricity market system. As an important promoter of the energy revolution and power reform, a new round of power system reform has brought profound changes to the energy industry and the power industry and the electricity market system has changed dramatically. With the release of the electricity market, market competition intensified. This paper analyzes the competition strategy of electricity sales market, analyzes the characteristics of market participants such as power generation enterprises, power grid enterprises, electricity sales companies and users, and puts forward the corresponding coping strategies to help the market participants to deal with the opportunities and challenges brought by power system reform, provide guidance and reference for the market participants.

Partial extinction, permanence and global attractivity innonautonomous n-species Lotka-Volterra competitivesystems with impulses

In this paper, the qualitative properties of general nonautonomous Lotka-Volterran-species competitive systems with impulsive e？ects are studied. Some new criteria on thepermanence, extinction and global attractivity of partial species are established by used themethods of inequalities estimate and Liapunov functions. As applications, nonautonomous twospecies Lotka-Volterra systems with impulses are discussed.

The importance of product positioning and global branding for sustaining competitive advantage within the companies＇ global marketing strategy

In today＇s globally competitive world, because of the globalization, new business patterns and the changing nature of consumers, the companies feel the necessity to act strategic in the market and to reach up the target markets and sustain maximum customer satisfaction in order to compete and survive. In this context, within the study it is tried to define product positioning in international markets and global branding strategies conceptually and to focus on their contributions to the overall competitive advantage of the company. Initially, the study tries to present the association between product positioning and global branding approaches of the companies and sustaining competitive advantage. Justifications for the examination of the importance of companies＇ international product positioning and global branding orientations as a basis of creating competitive advantage were derived from the literature. It is suggested that the companies＇ product positioning and global branding orientations and sustaining competitive advantage are the important aspects in multinational management and international business areas. Therefore, the purpose of this study is to evaluate the impact of product positioning and global branding strategies of the companies with special references to various industries and global brands.

2020 Global Energy Interconnection Conference (Asia Energy and Power Conference) Call for Papers

The 2020 Global Energy Interconnection Conference(Asia Energy and Power Conference)will be held on Nov.1-42020,Beijing,China.We are collecting research papers worldwide to publish the proceedings for the event.

Effect of Energy Market Globalization over Power Sector of GCC Region: A Short Review

Globalization of energy market in GCC countries is deepening not only through free-flowing international trade but also through foreign investment, market-driven domestic economies and industrialization. GCC nations are transforming their energy industry and market around the world which is promising their economic efficiency and technology development. Nevertheless, this open energy market across the world has raised a question about energy security and power demand. This energy market globalization has pushed the GCC Nations to pay attention to the control of supply and demand of power. Interconnection of power network between the GCC Region is optimistic pace to secure the future anticipated power fallouts. And also installation of Renewable Energy projects will support GCC to accommodate their increasing power demand. This paper discusses about how the energy market globalization has effect the power supply and demand of GCC nations, their concerns and recent progress towards its resolution.