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China's Digital Silk Road provides Beijing with a potent instrument to disrupt undersea cables and gain an advantage in the Indo-Pacific. Submarine fiber-optic cables are critical infrastructure yet vulnerable to sabotage. This paper examines how the planned Pakistan and East Africa Connecting Europe (PEACE) cable from China could become a new flashpoint in the Western Indian Ocean. The cable has strategic implications, allowing China to project power and leverage its technological edge. Its landing sites in Pakistan and Djibouti would anchor Chinese naval assets in key chokepoints. The civil-military fusion strategy also facilitates surveillance and espionage via the cables. To counter such threats, India and allies must secure submarine cables through monitoring, contingency planning, and multilateral cooperation. Investing in alternative "democratic digital networks" can also mitigate China's ambitions. Ultimately, submarine cables are emerging as a domain of geopolitical competition requiring policies that safeguard their resilience. [ABSTRACT FROM AUTHOR]

The strategic significance accorded to submarine cables has never been a static concept, but it has been homogenous: a focus on protecting cables from external threats. This article argues that because submarine cables have long had strategic value, they provide a means to examine the emerging concept of strategic technology competition between the United States and China. To do so, this article examines major changes to the submarine cable sector since 2015, including the success of Chinese company Huawei Marine, and US and other western government interventions in several cable projects. It characterises the strategic considerations exhibited by submarine cable activity in that period – influence building in third countries, a changing perception among the US and its partners of threat and protection priorities, and closer attention to cable security and surveillance considerations – and compares them with the traditional strategic values attached to submarine cables. It concludes strategic concerns about undersea cables includes a new concept: the construction and installation of cables as a strategic threat, and which adds complexity to a sector in which it is difficult to project influence. This article seeks to make a contribution to scholarship on strategic competition in emerging technologies. [ABSTRACT FROM AUTHOR]

China Fusion Engineering Experimental Reactor (CFETR) is a major scientific project independently designed and developed by China and jointly with international cooperation. Engineering design and project infrastructure construction are currently underway. The design goal of CFETR is 1.5–2.0 GW fusion power, and the central magnetic field is up to 15 Tesla, which is much larger than the design parameters of ITER under construction in Europe. In order to achieve the desired high magnetic field, the pre-research of Bi-2212 high temperature superconducting CICC magnet was carried out. The performance test of Bi-2212 cable is the most direct criterion for the successful development of the cable. New cable performance judgment method is proposed because of the long test time and high test cost of sub-size cables. Two cables are manufactured, and one cable is disassembled into single wires for performance evaluation. If the performance of single wires is not significantly attenuated in comparison with the performance of single wires that have not been twisted, we will conduct the second cable critical current test. The test results show that the method of dismantling the cable test is feasible. It is also feasible for cables of different structures. This method can be used to judge the performance of the cable in advance. This method is only suitable for detecting damage in the cable manufacturing process. [ABSTRACT FROM AUTHOR]

This article proposes a topological model capable of accounting for the scale and complexity of China’s digital infrastructure. Beginning with the troubled development of a submarine data cable between Los Angeles and Hong Kong, it identifies the limitations of topographical analyses of ICTs and then reviews theorizations of “the stack” as a topological model of planetary computation. To situate the stack model in the Chinese context, I draw on 3 case studies—QR codes, filtering, and cybersovereignty— exemplifying three topological configurations: the gateway, the sieve, and the dome. These configurations expand the conceptual vocabulary of the stack model at different scales, and provide useful tools for the analysis of computational infrastructures in Asia and beyond. [ABSTRACT FROM AUTHOR]

To achieve a high penetration of renewable energy, wind power development in China has gradually moved to diverse manifestation (e.g., centralized onshore, low wind speed, and offshore wind power). However, preexisting studies regarding wind power cost neglect to consider the respective characteristics of different development scenarios. In this paper, the overall levelized cost of energy (OLCOE) model is established for different scenarios. Taking China's wind farm data as an example, the impact of development scenarios and wind power permeability on OLCOE and its cost components is quantitatively analysed. The results show that, (1) in the low penetration scenario, low wind speed power has the best economy and is beneficial to the conventional units; (2) the large-scale development of offshore wind power requires a reduction in the cost of offshore wind turbines and submarine cables; and (3) at present, onshore centralized wind power has economic advantages, but there is little room for its cost reduction. [ABSTRACT FROM AUTHOR]

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Based on real sea conditions of the national wave energy demonstration site in Wanshan sea area of Zhuhai City, China, some numerical experiments are carried out to simulate the submarine cables initial laying process of the Wave Energy Booster Station in this demonstration site. The numerical model is established with the Orcaflex software employed. The motion response of laying ship and the hydrodynamic characteristics of submarine cables are simulated here under three sea conditions, i.e. usual waves, waves with current combined and possible extreme waves. Research results show that the tension and curvature of the cable are large under the condition for wave direction perpendicular to the ship axial direction, which is a relatively bad sea condition. The current also has some influences on the submarine cable laying, and the maximum effective tension of cable produced by the combined wave-current action is 1.35 times that of cable with the wave action alone. When extreme waves appear, pitch, heave and heave acceleration of the laying ship and tension of the cable ends increases obviously. And the variation of effective tension at both cable ends can reach 1.67 times that of cable ends under usual random waves. The numerical model and research results in this paper can provide some guidance for the research and construction of the cable laying of booster stations for marine renewable energy power plants in real sea conditions. [ABSTRACT FROM AUTHOR]

• A model to evaluate the impact of EV charging loads on cable is presented. • Impacts on cable ampacity, derating factor and temperature are analyzed. • The impacts are analyzed in typical charging scenarios and EV penetration. To meet the rapidly growing electric vehicle (EV) charging demand, it is important to determine maximum ampacity and avoid overloading of Medium Voltage (MV) cables in power distribution systems. Previous works on modelling and analysis of relationship between the load demand of MV cables and EV penetration level did not consider the contribution of harmonic currents. This paper presents a methodology for modelling and analysis of the impact of EV charging loads on cable ampacity and temperature in presence of different levels harmonic currents under two typical scenarios of EV charging modes, i.e., uncontrolled domestic charging scenario and uncontrolled off-peak domestic charging. The proposed method determines the ampacity and temperature of three-core cable taking account for cable geometry, harmonic levels, stochastic nature of the charging power, start time of individual charging, seasonal temperature under different EV penetrations. A generic urban distribution network with residential load ratio of 0.7, which is representative of urban residential distribution network in China, is adopted as an example. Results show that the ampacity of a 400 mm2 10 kV cross-linked polyethylene (XLPE) cable decreased by 10.79 A and 2.03% when the harmonic level is at the maximum allowed limit as given in IEC 61000-3-2. Meanwhile, the ampacity decreased by 23.34 A and 4.09% at the maximum limit given in IEC 61000-3-4. In presence of 36.15% and 41.66% total harmonic distortion current which are the most serious harmonic distortion in the example network with 30% EV penetration, cable ampacity decreased by 42.86 A, 8.06% and 61.35 A, 11.35% respectively. [ABSTRACT FROM AUTHOR]

The effect of dose rates is the critical concern of irradiation testing in equipment qualification for polymeric materials used in nuclear power plants, and the rule 'the lower dose rates, the severer degradation' is always regarded as the truth due to the limited diffusion of oxidation. But it's obviously not economic and practical from the engineering point of view. In this paper, aiming at investigating such dose rate effects, gamma irradiation testing with multiple dose rates was performed on one domestically manufactured ethylene-propylene rubber that was intended for the nuclear cable insulations of the advanced pressurized water reactors in China. In detail, before and after testing, the mechanical, electrical and chemical properties were measured from the specimens, and their fractographs after tensile test were observed, and particularly the oxidation profiles on the whole cross sections of them were detected by the infrared microscope to quantitatively compare the degradation extent under different dose rates. Based on the results, the correlation among the dose rates, the measured properties, and the penetration depth of oxidation was clarified, the relevant degradation mechanisms were discussed, and a suitable dose rate for engineering practice was recommended. The effect of dose rate is the critical concern of irradiation testing in equipment qualification for polymeric materials used in nuclear power plants, and the rule 'the lower dose rate, the severer degradation' is always regarded as the truth due to the limited diffusion of oxidation. But it's obviously not economic and practical from the engineering point of view. In this paper, for purpose of investigating such dose rate effect, gamma irradiation testing with multiple dose rates was performed on one domestically manufactured ethylene-propylene rubber that was intended for use as the nuclear cable insulations in China. Before and after testing, upon the specimens, the mechanical, electrical and chemical properties were measured, the fractographs were observed, and particularly the oxidation profiles on the whole cross sections were detected to compare the degradation extent under different dose rates. The results indicated that the severest degradation was found occur at the intermediate dose rate instead of the lowest one due to the competing mechanisms between plasticizers volatilization and chain scission, seen in Fig. 1. But the oxidation penetration depth discovered indeed increases with the decrease of the dose rates, and even obeys roughly an arithmetic progression relation, as revealed in Fig. 2, from which the conventional concept that the degradation extent is inversely proportional to the dose rates is testified. Based on the results, the correlation among the measured properties, the penetration depth and extent of oxidation, and the dose rates were clarified, the relevant degradation mechanisms were discussed, and a suitable dose rate for engineering practice was recommended. Unlabelled Image • Irradiation testing with multiple dose rates was performed on one ethylene-propylene rubber to study the dose rate effect. • By infrared microscope, the dose rate effect based on the oxidation profile as extent and penetration depth was demonstrated. • Degradation of the measured mechanical, electrical and chemical properties was found influenced by the dose rate effect. • This paper will facilitate deeper understanding of the dose rate effect and the theories of diffusion-limited oxidation. [ABSTRACT FROM AUTHOR]

The China-Pakistan Economic Corridor (CPEC) is considered as an excellent breakthrough for improving the economic and security situation in the region. The estimated worth of CPEC is 62$ billion which is comprising of 49 developmental projects. China-Pakistan Fiber Optic Project (CPFOP) is one of the core projects among these, which will deliver safe route of voice traffic between both countries. CPFOP is greatly beneficial in terms of enhanced security and revenue generation. Currently, Pakistan's international connectivity is via submarine cables. CPFOP will provide an alternative route for international telecom traffic and also assist in achieving the rapidly growing internet traffic demand in Pakistan. It is estimated that 17 million people will get benefit from this project. However, every project has some undesirable impacts. The aim of this research paper is twofold; 1st to trace out the pros and cons of CPFOP. 2ndly, performing a risk assessment of CPFOP by using Fuzzy VIKOR technique. This approach will help in prioritizing a list of failure modes of Fiber Optic Cable (FOC). Lastly, this paper will help authorities for optimizing and safeguarding national interest in the wake of CPFOP. [ABSTRACT FROM AUTHOR]

• A multiple criteria analysis method is proposed to compare renewable energy and traditional solutions for off-grid island power supply. • Life cycle cost is used to build the economic model. • The fuzzy analytic hierarchy process is used to quantify the risk level. • A simulation platform is built to obtain the energy utilization. • Applied to the actual project to verify the feasibility of the method. Renewable energy microgrids are a new option for powering remote islands. To explore the feasibility of constructing island microgrid in China, based on the failed Dongfushan Island Demonstration Microgrid Project caused by equipment failure, low economic benefits, low residents' satisfaction, and poor power supply stability, this paper compares two power supply methods, microgrid and submarine cable. A systematic multiple criteria analysis method is established to compare these two methods, including economic analysis, risk assessment, energy spilled and energy shortage. Net present value and the life-cycle cost method are used to establish the economic cost model. Fuzzy analytic hierarchy process is used to establish the risk assessment model. Additionally, the simulation using PVsyst software is used to calculate the energy spilled and energy shortage. Furthermore, future trends are predicted with data to provide suggestions for decision-makers. Multiple criteria analysis results showed that energy spilled and shortages are inevitable for the use of microgrid on seasonally tourist islands like Dongfushan Island, with energy spilled and shortages rate as high as 50.11% and 37.57% in the worst case. The microgrid risk level is relatively low risk, higher than the lowest risk level for submarine cables. At full capacity, the cost of microgrid (34.03 million yuan) is comparable to submarine cables (30.31 million yuan), making the latter more suitable for power supply due to its better reliability. [Display omitted] [ABSTRACT FROM AUTHOR]

• The accurate distributed impedance matrices of the single-core submarine cable system are established to calculate the electrical parameters considering the effects of the multilayer soil laying condition and semiconducting sheath. • The improved multiconductor analysis method based on the coupled line model and matrix cascading algorithm is proposed to further improve the calculation efficiency. • The characteristics of the three main grounding methods for the single-core submarine cables are fully revealed and analysed. The grounding system is a decisive factor in the safety and reliability of submarine cables used for marine transmission systems. In this paper, the accurate matrices of distributed impedance of the submarine cable system are established considering the effect of the multilayer soil laying condition. The improved multiconductor analysis method, which has good calculation efficiency and accuracy, is proposed to analyse the cable grounding system under the steady-state power-frequency operating conditions. The performance of different grounding methods of the Zhoushan 500 kV XLPE submarine cable project in Zhejiang Province of China is investigated. The results show that the grounding methods of solid-bonding with intermediate grounding points and solid-bonding with semiconducting sheath are more promising than the conventional solid-bonding grounding method for the long submarine cable system due to the reduction in the induced voltage of metallic sheath as well as lower power loss. A guideline for the grounding system design of the long submarine cable lines is proposed in this paper. [ABSTRACT FROM AUTHOR]

Submarine cables are critical infrastructure that carry nearly all internet traffic. However, unclear international governance does not always guarantee their protection, leaving global information networks vulnerable to sabotage and espionage. China's access to submarine cables for strategic manipulation is greatly expanded through the Digital Silk Road and territorial claims in the South China Sea, posing a clear threat that requires a U.S. response. Current U.S. policy is uncoordinated and can be sorted into the isolationist, cooperative, competitive, and militaristic responses, which each present unique frameworks for future action. The isolationist response would disconnect the United States from insecure cable networks, limiting China's influence over U.S. assets but reducing international connectivity. The cooperative response emphasizes international norms-setting processes to achieve multilateral agreements protecting cables from state influences. The competitive response advocates U.S. competition with China in the submarine cable market through alternate assistance programs, which would increase the redundancy of a secure network. Finally, the militaristic response explores the role of America's military in defending submarine cables from foreign exploitation. This article recommends that future policy emphasize a combination of the competitive and militaristic responses in order to most immediately and effectively address China's threat to information security along submarine cables while minimizing U.S. risk. [ABSTRACT FROM AUTHOR]

Offshore wind farms have developed fast as an environmentally friendly source of energy. The submarine power cable of the offshore wind farm, used for connecting power generation devices to onshore equipment, may have a significant impact on navigation safety and is prone to being damaged (e.g. caused by fishing or emergency anchoring by ships) when adopting unfavorable routing. This paper proposes a fuzzy evidential reasoning method for submarine power cable routing selection of the offshore wind farm by comprehensively considering the conditions for cable laying and its influence on maritime safety. The kernel of this approach is to establish a three-layer decision-making framework after fuzzification of the input variables, to derive the belief rule base, and to obtain the optimal routing from the submarine power cable candidates using evidential reasoning and index value. The proposed approach is applied to a real routing selection problem of a submarine power cable for an offshore wind farm in Zhejiang Province of China. The resulting choice corresponds to the discussions in a workshop unanimously. • A fuzzy evidential reasoning method is developed for submarine power cable routing selection of the offshore wind farm. • Various criteria are identified with special consideration of maritime safety. • A three-layer decision making framework is established for submarine power cable routing selection. • Case study in the East China Sea is used to validate the proposed method. [ABSTRACT FROM AUTHOR]

For new submarine hot oil pipelines, accurate simulation of preheating is difficult owing to complex transient flow and coupled heat transfer happening. Using quasi-steady equations to simulate preheating is inadequate as the hydraulic transient phenomenon is neglected. Considering this fact, this paper constructs an unsteady flow and heat transfer coupled mathematical model for the preheating process. By combining the double method of characteristics (DMOC) and finite element method (FEM), a numerical methodology is proposed, namely, DMOC-FEM. Its accuracy is validated by field data collected from the Bohai sea, China, showing the mean absolute percentage error (MAPE) of 4.27%. Simulation results demonstrate that the preheating medium mainly warms submarine pipe walls rather than the surrounding subsea mud. Furthermore, during the preheating process, the equivalent overall heat transfer coefficients deduced performs more applicably than the inverse-calculation method in presenting the unsteady propagation of fluid temperature with time and distance. Finally, according to the comparison results of 11 preheating plans, subject to a rated heat power and maximum flow, the preheating parameter at a lower fluid temperature combined with a higher flow rate will produce a better preheating effect. [ABSTRACT FROM AUTHOR]

In order to improve the practice in the operation and maintenance of high voltage (HV) cables, this paper proposes a fault location method based on the monitoring of cable sheath currents for use in cross-bonded HV cable systems. This method first analyzes the power–frequency component of the sheath current, which can be acquired at cable terminals and cable link boxes, using a Fast Fourier Transform (FFT). The cable segment where a fault occurs can be localized by the phase difference between the sheath currents at the two ends of the cable segment, because current would flow in the opposite direction towards the two ends of the cable segment with fault. Conversely, in other healthy cable segments of the same circuit, sheath currents would flow in the same direction. The exact fault position can then be located via electromagnetic time reversal (EMTR) analysis of the fault transients of the sheath current. The sheath currents have been simulated and analyzed by assuming a single-phase short-circuit fault to occur in every cable segment of a selected cross-bonded high voltage cable circuit. The sheath current monitoring system has been implemented in a 110 kV cable circuit in China. Results indicate that the proposed method is feasible and effective in location of HV cable short circuit faults. [ABSTRACT FROM AUTHOR]

The article offers a brief historical account on the telegraphic networks in China. The expansion of the telegraphic networks into Asia was brought by economic and political intention, such as the growth of Western trade with China. In the business communities of Hong Kong and Shanghai, telegraphs were seen as important for the expansion of trade. One of the leading figures of telegraph communication in the country is the Eastern Extension of John Pender.