Both the EU and China remain committed to safeguarding the multilateral trading system,which is in alignment with the bilateral and common interests of the world.
On March 24,the international symposium themed“Strengthen the Role of the United Nations and Promote Multilateralism”was held in Beijing.The event was hosted by the Ministry of Foreign Affairs of China,and supported...On March 24,the international symposium themed“Strengthen the Role of the United Nations and Promote Multilateralism”was held in Beijing.The event was hosted by the Ministry of Foreign Affairs of China,and supported by China Institute of International Studies(CIIS),the United Nations Association of China.展开更多
The global trade governance system is the institutional safeguard for maintaining the operation of world trade. It consists of governance entities, platforms and rules. Since the end of World War Ⅱ, the global trade ...The global trade governance system is the institutional safeguard for maintaining the operation of world trade. It consists of governance entities, platforms and rules. Since the end of World War Ⅱ, the global trade governance system has mainly referred to the multilateral trading system, with the General Agreement on Tariffs and Trade(GATT) and the World Trade Organization(WTO) serving as governance platforms.展开更多
In an era marked by rising protectionism and geopolitical tensions,the world faces a stark choice:embrace multilateral cooperation or succumb to unilateral hegemony.The United States’punitive tariff policies have exp...In an era marked by rising protectionism and geopolitical tensions,the world faces a stark choice:embrace multilateral cooperation or succumb to unilateral hegemony.The United States’punitive tariff policies have exposed the negative effect of economic coercion and isolation.Meanwhile,China’s commitment to openness,innovation,and shared prosperity offers a contrast,a testament to the enduring vitality of multilateralism and global integration.展开更多
Today,the world is undergoing profound changes unseen in a century,and a host of global challenges continue to emerge.The international community urgently requires effective global governance.As Chinese President Xi J...Today,the world is undergoing profound changes unseen in a century,and a host of global challenges continue to emerge.The international community urgently requires effective global governance.As Chinese President Xi Jinping has pointed out,multilateralism is the inevitable choice for addressing the world’s difficulties and challenges.1 However,various negative trends in international politics are undermining or impeding the effectiveness of multilateralism and aggravating the global governance deficit.Against this backdrop,it is essential to reassess the importance of multilateralism in global governance,identify the challenges it faces,and explore feasible pathways for collective action to advance global governance.展开更多
Safeguarding the resilience and stability of global industrial and supply chains provides a crucial guarantee for world economic development.Moreover,it aligns with the common interests of all countries.At its third p...Safeguarding the resilience and stability of global industrial and supply chains provides a crucial guarantee for world economic development.Moreover,it aligns with the common interests of all countries.At its third plenary session,the 20th Central Commit tee of the Communist Par ty of China(CPC)stressed that it would“facilitate international cooperation in industrial and supply chains”.China is firmly committed to supporting and enhancing the multilateral trading system centered on the World Trade Organization(WTO)in order to ensure the smooth and stable operation of these chains.展开更多
This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficia...This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficial cooperation,and firmly upheld multilateralism,bringing tangible benefits to both peoples and making a significant contribution to global peace and development.展开更多
After the 2008 global financial crisis, the global governance architecture underwent significant changes, accompanied by transformations in political, economic, diplomatic, and social spheres. What we had learnt since...After the 2008 global financial crisis, the global governance architecture underwent significant changes, accompanied by transformations in political, economic, diplomatic, and social spheres. What we had learnt since the end of World War Ⅱ was unable to make sense of the evolution and direction of this architecture.展开更多
China-Africa cooperation sets a benchmark for equitable development in a multipolar world Despite rising unilateralism and protectionism in the West and increasing uncertainties in global trade,China-Africa economic a...China-Africa cooperation sets a benchmark for equitable development in a multipolar world Despite rising unilateralism and protectionism in the West and increasing uncertainties in global trade,China-Africa economic and trade cooperation remains on a fast track,backed by concrete actions towards common modernisation.This collaboration reinforces solidarity across the Global South and contributes to greater stability and confidence in the global multilateral trading system.展开更多
On June 18, 2025, the second ChinaCentral Asia Summit was held in Astana, Kazakhstan. The member states of the China-Central Asia mechanism emphasized the importance of further deepening multilateral cooperation based...On June 18, 2025, the second ChinaCentral Asia Summit was held in Astana, Kazakhstan. The member states of the China-Central Asia mechanism emphasized the importance of further deepening multilateral cooperation based on principles of equality, mutual respect, and mutual benefit. They declared their commitment to continue strengthening friendly relations, deepening political trust, and expanding economic cooperation among the six nations.展开更多
The U.S.administration's decision tounilaterally impose sweeping tariff increas-es on tmported goods represents a signifi-cant challenge to the existing global tradingsystem,which has long been structuredaround mu...The U.S.administration's decision tounilaterally impose sweeping tariff increas-es on tmported goods represents a signifi-cant challenge to the existing global tradingsystem,which has long been structuredaround multilateral(WTO),regional,andbilateral(FTA)trade agreements.展开更多
Due to high energy density,clean combustion products and abundant resources,natural gas hydrates(NGHs)have been regarded as an important clean energy source with the potential for large-scale development and utilizati...Due to high energy density,clean combustion products and abundant resources,natural gas hydrates(NGHs)have been regarded as an important clean energy source with the potential for large-scale development and utilization.However,pilot tests in NGHs show that their production rates are far below commercial needs.Multilateral well technology may lead to a solution to this problem because it can dramatically expand the drainage area of production wells.This paper presents the practical rate transient analysis for multilateral horizontal wells in NGHs.In developing solution to the diffusivity equation of multilateral horizontal wells in NGHs,the superposition principle and reciprocity are applied.We wrote the governing equation in cylindrical coordinates to describe the NGH flow process.We used the moving boundaries and dissociation coefficients to model the solid-to-gas transition process in hydrates.To obtain solutions for flow in hydrate reservoirs,we used Laplace transforms and the Stehfest numerical inversion method.Superposition principle and Gaussian elimination are applied to obtain the desired solution for multilateral horizontal wells.We validated our proposed model with a commercial numerical simulator.By performing sensitivity analyses,effects on production behavior of the number of branches,dissociation coefficient,radius of the region with dissociated hydrate,and dispersion ratio are determined.A synthetic case study is conducted to show the typical production behaviors.展开更多
Currently, cybersecurity and cyber resilience are emerging and urgent issues in nextgeneration air traffic surveillance systems, which depend primarily on Automatic Dependent Surveillance-Broadcast(ADS-B) owing to its...Currently, cybersecurity and cyber resilience are emerging and urgent issues in nextgeneration air traffic surveillance systems, which depend primarily on Automatic Dependent Surveillance-Broadcast(ADS-B) owing to its low cost and high accuracy. Unfortunately, ADS-B is prone to cyber-attacks. To verify the ADS-B positioning data of aircraft, multilateration(MLAT)techniques that use Time Differences of Arrivals(TDoAs) have been proposed. MLAT exhibits low accuracy in determining aircraft positions. Recently, a novel technique using a theoretically calculated TDoA fingerprint map has been proposed. This technique is less dependent on the geometry of sensor deployment and achieves better accuracy than MLAT. However, the accuracy of the existing technique is not sufficiently precise for determining aircraft positions and requires a long computation time. In contrast, this paper presents a reliable surveillance framework using an Actual TDoA-Based Augmentation System(ATBAS). It uses historically recorded real-data from the OpenSky network to train our TDoA fingerprint grid network. Our results show that the accuracy of the proposed ATBAS framework in determining the aircraft positions is significantly better than those of the MLAT and expected TDoA techniques by 56.93% and 48.86%, respectively. Additionally, the proposed framework reduced the computation time by 77% compared with the expected TDoA technique.展开更多
This paper presents the estimation of three-dimensional volumetric errors of a machining center by using a tracking interferometer. A tracking interferometer is a laser interferometer with the mechanism to steer the l...This paper presents the estimation of three-dimensional volumetric errors of a machining center by using a tracking interferometer. A tracking interferometer is a laser interferometer with the mechanism to steer the laser direction to follow a target retroreflector. Based on the triangulation principle, the three-dimensional position of the target can be estimated from measured laser displacements. Its capability to measure three-dimensional positioning errors for arbitrary trajectories is important for the indirect measurement of the machine's kinematic model. This paper presents experimental investigation of the estimation accuracy of the multilateration-based measurement by a tracking interferometer. A tracking interferometer developed by a part of the authors is used in experiments. In the present experiment, the measured volume of target positions was 100 mm × 100 mm × 100 mm. The estimation accuracy of targets within this volume was not sufficiently high compared to the positioning error of the measured machine tool. The results of the experiment and simulation show that the estimation uncertainty is dependent on tracking interferometer locations relative to target locations. Error sensitivity analysis shows that wider distribution of tracker positions in XY improves the estimation accuracy.展开更多
Due to the particularity of its location algorithm,there are some unique difficulties and features regarding the test of target motion states of multilateration(MLAT)system for airport surface surveillance.This paper ...Due to the particularity of its location algorithm,there are some unique difficulties and features regarding the test of target motion states of multilateration(MLAT)system for airport surface surveillance.This paper proposed a test method applicable for the airport surface surveillance MLAT system,which can effectively determine whether the target is static or moving at a certain speed.Via a normalized test statistic designed in the sliding data window,the proposed method not only eliminates the impact of geometry Dilution of precision(GDOP)effectively,but also transforms the test of different motion states into the test of different probability density functions.Meanwhile,by adjusting the size of the sliding window,it can fulfill different test performance requirements.The method was developed through strict theoretical extrapolation and performance analysis,and simulations results verified its correctness and effectiveness.展开更多
文摘Both the EU and China remain committed to safeguarding the multilateral trading system,which is in alignment with the bilateral and common interests of the world.
文摘On March 24,the international symposium themed“Strengthen the Role of the United Nations and Promote Multilateralism”was held in Beijing.The event was hosted by the Ministry of Foreign Affairs of China,and supported by China Institute of International Studies(CIIS),the United Nations Association of China.
文摘The global trade governance system is the institutional safeguard for maintaining the operation of world trade. It consists of governance entities, platforms and rules. Since the end of World War Ⅱ, the global trade governance system has mainly referred to the multilateral trading system, with the General Agreement on Tariffs and Trade(GATT) and the World Trade Organization(WTO) serving as governance platforms.
文摘In an era marked by rising protectionism and geopolitical tensions,the world faces a stark choice:embrace multilateral cooperation or succumb to unilateral hegemony.The United States’punitive tariff policies have exposed the negative effect of economic coercion and isolation.Meanwhile,China’s commitment to openness,innovation,and shared prosperity offers a contrast,a testament to the enduring vitality of multilateralism and global integration.
文摘Today,the world is undergoing profound changes unseen in a century,and a host of global challenges continue to emerge.The international community urgently requires effective global governance.As Chinese President Xi Jinping has pointed out,multilateralism is the inevitable choice for addressing the world’s difficulties and challenges.1 However,various negative trends in international politics are undermining or impeding the effectiveness of multilateralism and aggravating the global governance deficit.Against this backdrop,it is essential to reassess the importance of multilateralism in global governance,identify the challenges it faces,and explore feasible pathways for collective action to advance global governance.
文摘Safeguarding the resilience and stability of global industrial and supply chains provides a crucial guarantee for world economic development.Moreover,it aligns with the common interests of all countries.At its third plenary session,the 20th Central Commit tee of the Communist Par ty of China(CPC)stressed that it would“facilitate international cooperation in industrial and supply chains”.China is firmly committed to supporting and enhancing the multilateral trading system centered on the World Trade Organization(WTO)in order to ensure the smooth and stable operation of these chains.
文摘This year marks the 50th anniversary of the establishment of diplomatic relations between China and the EU.Over half a century,China and the EU have steadily enhanced political mutual trust,deepened mutually beneficial cooperation,and firmly upheld multilateralism,bringing tangible benefits to both peoples and making a significant contribution to global peace and development.
文摘After the 2008 global financial crisis, the global governance architecture underwent significant changes, accompanied by transformations in political, economic, diplomatic, and social spheres. What we had learnt since the end of World War Ⅱ was unable to make sense of the evolution and direction of this architecture.
文摘China-Africa cooperation sets a benchmark for equitable development in a multipolar world Despite rising unilateralism and protectionism in the West and increasing uncertainties in global trade,China-Africa economic and trade cooperation remains on a fast track,backed by concrete actions towards common modernisation.This collaboration reinforces solidarity across the Global South and contributes to greater stability and confidence in the global multilateral trading system.
文摘On June 18, 2025, the second ChinaCentral Asia Summit was held in Astana, Kazakhstan. The member states of the China-Central Asia mechanism emphasized the importance of further deepening multilateral cooperation based on principles of equality, mutual respect, and mutual benefit. They declared their commitment to continue strengthening friendly relations, deepening political trust, and expanding economic cooperation among the six nations.
文摘The U.S.administration's decision tounilaterally impose sweeping tariff increas-es on tmported goods represents a signifi-cant challenge to the existing global tradingsystem,which has long been structuredaround multilateral(WTO),regional,andbilateral(FTA)trade agreements.
基金This work received funding support from National Natural Science Foundation of China(12202042),Highend Foreign Expert Introduction Program(G2023105006L)China Postdoctoral Science Foundations(2021M700391)Fundamental Research Funds for the Central Universities(QNXM20220011,FRFTP-22-119A1,FRF-IDRY-22-001)。
文摘Due to high energy density,clean combustion products and abundant resources,natural gas hydrates(NGHs)have been regarded as an important clean energy source with the potential for large-scale development and utilization.However,pilot tests in NGHs show that their production rates are far below commercial needs.Multilateral well technology may lead to a solution to this problem because it can dramatically expand the drainage area of production wells.This paper presents the practical rate transient analysis for multilateral horizontal wells in NGHs.In developing solution to the diffusivity equation of multilateral horizontal wells in NGHs,the superposition principle and reciprocity are applied.We wrote the governing equation in cylindrical coordinates to describe the NGH flow process.We used the moving boundaries and dissociation coefficients to model the solid-to-gas transition process in hydrates.To obtain solutions for flow in hydrate reservoirs,we used Laplace transforms and the Stehfest numerical inversion method.Superposition principle and Gaussian elimination are applied to obtain the desired solution for multilateral horizontal wells.We validated our proposed model with a commercial numerical simulator.By performing sensitivity analyses,effects on production behavior of the number of branches,dissociation coefficient,radius of the region with dissociated hydrate,and dispersion ratio are determined.A synthetic case study is conducted to show the typical production behaviors.
文摘Currently, cybersecurity and cyber resilience are emerging and urgent issues in nextgeneration air traffic surveillance systems, which depend primarily on Automatic Dependent Surveillance-Broadcast(ADS-B) owing to its low cost and high accuracy. Unfortunately, ADS-B is prone to cyber-attacks. To verify the ADS-B positioning data of aircraft, multilateration(MLAT)techniques that use Time Differences of Arrivals(TDoAs) have been proposed. MLAT exhibits low accuracy in determining aircraft positions. Recently, a novel technique using a theoretically calculated TDoA fingerprint map has been proposed. This technique is less dependent on the geometry of sensor deployment and achieves better accuracy than MLAT. However, the accuracy of the existing technique is not sufficiently precise for determining aircraft positions and requires a long computation time. In contrast, this paper presents a reliable surveillance framework using an Actual TDoA-Based Augmentation System(ATBAS). It uses historically recorded real-data from the OpenSky network to train our TDoA fingerprint grid network. Our results show that the accuracy of the proposed ATBAS framework in determining the aircraft positions is significantly better than those of the MLAT and expected TDoA techniques by 56.93% and 48.86%, respectively. Additionally, the proposed framework reduced the computation time by 77% compared with the expected TDoA technique.
文摘This paper presents the estimation of three-dimensional volumetric errors of a machining center by using a tracking interferometer. A tracking interferometer is a laser interferometer with the mechanism to steer the laser direction to follow a target retroreflector. Based on the triangulation principle, the three-dimensional position of the target can be estimated from measured laser displacements. Its capability to measure three-dimensional positioning errors for arbitrary trajectories is important for the indirect measurement of the machine's kinematic model. This paper presents experimental investigation of the estimation accuracy of the multilateration-based measurement by a tracking interferometer. A tracking interferometer developed by a part of the authors is used in experiments. In the present experiment, the measured volume of target positions was 100 mm × 100 mm × 100 mm. The estimation accuracy of targets within this volume was not sufficiently high compared to the positioning error of the measured machine tool. The results of the experiment and simulation show that the estimation uncertainty is dependent on tracking interferometer locations relative to target locations. Error sensitivity analysis shows that wider distribution of tracker positions in XY improves the estimation accuracy.
基金supported by the National Science and Technology Pillar Program of China (No.2011BAH24B06)the National Nature Science Foundation of China+1 种基金Chinese Civil Aviation Jointly Funded Foundation Project (No.U1433129)the Sichuan Provincial Department of Education Foundation(No.13ZB0287)
文摘Due to the particularity of its location algorithm,there are some unique difficulties and features regarding the test of target motion states of multilateration(MLAT)system for airport surface surveillance.This paper proposed a test method applicable for the airport surface surveillance MLAT system,which can effectively determine whether the target is static or moving at a certain speed.Via a normalized test statistic designed in the sliding data window,the proposed method not only eliminates the impact of geometry Dilution of precision(GDOP)effectively,but also transforms the test of different motion states into the test of different probability density functions.Meanwhile,by adjusting the size of the sliding window,it can fulfill different test performance requirements.The method was developed through strict theoretical extrapolation and performance analysis,and simulations results verified its correctness and effectiveness.