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News Article | April 26, 2017
Site: news.yahoo.com

BEIJING (Reuters) - China launched its first domestically built aircraft carrier on Wednesday amid rising tension over North Korea and worries about Beijing's assertiveness in the South China Sea. State media has quoted military experts as saying the carrier, China's second and built in the northeastern port of Dalian, is not expected to enter service until 2020, once it has been kitted out and armed. Foreign military analysts and Chinese media have for months published satellite images, photographs and news stories about the second carrier's development. China confirmed its existence in late 2015. The launch "shows our country's indigenous aircraft carrier design and construction has achieved major step-by-step results", Xinhua news agency said. State television showed the carrier, its deck lined in red flags, being pushed by tug boats into its berth. Fan Changlong, a vice chairman of China's powerful Central Military Commission, presided over the ceremony, Xinhua said, during which a bottle of champagne was broken on the bow. The launch follows China's celebration on Sunday of the 68th birthday of the founding of the Chinese navy, and comes amid renewed tensions between North Korea and the United States over Pyongyang's nuclear and missile programs. Little is known about China's aircraft carrier program, which is a state secret. But the government has said the new carrier's design draws on experiences from the country's first carrier, the Liaoning, bought second-hand from Ukraine in 1998 and refitted in China. The new conventionally powered carrier will be able to operate China's Shenyang J-15 fighter jets. Unlike the U.S. navy's longer-range nuclear carriers, both of China's feature Soviet-design ski-jump bows, intended to give fighter jets enough lift to take off from their shorter decks. But they lack the powerful catapult technology for launching aircraft of their U.S. counterparts. "NO NEED" TO MATCH THE UNITED STATES China's navy has been taking an increasingly prominent role in recent months, with a rising star admiral taking command, its first aircraft carrier sailing around self-ruled Taiwan and new Chinese warships popping up in far-flung places. The Liaoning has taken part in military exercises, including in the South China Sea, but is expected to serve more as a training vessel. State media has said the new carrier will be more dedicated to military and humanitarian operations. China claims almost all the South China Sea, believed to have huge deposits of oil and gas, through which about $5 trillion in ship-borne trade passes every year, and has been building up military facilities like runways on the islands it controls. Brunei, Malaysia, the Philippines, Taiwan and Vietnam also have claims. Taiwan, claimed by Beijing as its own, has said China is actually building two new aircraft carriers, but China has not officially confirmed the existence of another carrier. Chinese state media has quoted experts as saying that the country needs at least six carriers. The United States operates 10 and plans to build two more. Major General Chen Zhou, a researcher at the Academy of Military Science, told reporters in March that China would not exceed the United States in carrier groups. "China has no need for this," he said. Sam Roggeveen, a senior fellow at the Sydney-based Lowy Institute, said that by the time China had half that number, it could go toe-to-toe with the U.S. navy in the Asia-Pacific. "Given that the Americans have global obligations and responsibilities but China doesn't, then effectively by that point they would be evenly matched," Roggeveen said. Most experts agree that developing such a force will be a decades-long endeavor but the launch of the second carrier holds a certain prestige value for Beijing, seen by many analysts as keen to eventually erode U.S. military prominence in the region. "With two aircraft carriers you could say without much fear of contradiction that China, other than the United States, is the most powerful maritime force in the Asia-Pacific," Roggeveen said.


Fu Y.,Beijing University of Posts and Telecommunications | Yu Y.,Beijing University of Posts and Telecommunications | Song M.,Beijing University of Posts and Telecommunications | Zhan X.,Academy of Military Science
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Weighted sequential pattern mining algorithms discover weighted sequences with considering the different significance of each item in a sequence database. But current algorithms have not considered the importance of the itemset-intervals information between the two items in a same itemset. Hence, although a large number of sequences had been discovered, most of them are not useful for analysis. In this study, we propose a new algorithm, called ItemSet-interval Weighted Sequences (ISiWS), to solve the problem about efficient discovering useful sequences. In ISiWS, a matrix structure, called Transaction Bit Matrix (TBM), represents a sequence. ISiWS first uses TBMs to represent the sequences in a sequence database. Then, it utilizes projected technology to discover weighted sequences, and an approximate sequence match algorithm is applied to calculate support of sequences based on their itemset-intervals. Experiments show that ISiWS produces a significantly less number of weighted sequences than those of WSpan. © 2014 Springer International Publishing.


Zhong Y.,Tsinghua University | Hao J.,Academy of Military Science | Dai Y.,Tsinghua University
Qinghua Daxue Xuebao/Journal of Tsinghua University | Year: 2012

This paper describes a Hash-chain based anonymous incentive protocol to stimulate forwarding cooperation between nodes in position-based routing for mobile ad-hoc networks (MANET). The protocol uses a Hash-chain based micro-payment mechanism with location-aided routing for MANET to stimulate the real-time forwarding cooperation and to improve the routing performance of the privacy protection routing in untrusted MANET scenarios. Security analyses indicate that this protocol can defend against impersonation attacks and relay attacks in position-based routing while providing privacy to the forwarders. Efficiency analyses show that it stimulates anonymous selfish forwarders in real time.


Zhong Y.,Tsinghua University | Hao J.,Academy of Military Science
Jiefangjun Ligong Daxue Xuebao/Journal of PLA University of Science and Technology (Natural Science Edition) | Year: 2014

An estimation method was proposed for the information support efficiency of the network attacks in order to estimate the support efficiency of the network attacks to the information operations. Based on the concept of system entropy, firstly a method was proposed to calculate the weights of the indexes based on the Analytic Hierarchy Process, then a calculation method of the difference of integration system entropy under the network attacks was given and a simulation experiment presented to evaluate the support efficiency of route attacks to a military wireless sensor network. The method can synthetically measure the influence of the network attacks to the information systems, and is a valuable method to estimate the influence of the network attacks to the information operations.


Zhong Y.,Tsinghua University | Hao J.-G.,Academy of Military Science | Dai Y.-Q.,Tsinghua University
Tien Tzu Hsueh Pao/Acta Electronica Sinica | Year: 2013

The routing performance issues in untrusted environments are the serious challenges for the privacy protection routing protocols in mobile ad-hoc networks (MANET). In order to encourage the selfish nodes and improve the routing performance in untrusted environments, this paper proposes an anonymous incentive mechanism based on hash-chain for the location-aided routing protocols. By using the efficiency and irreversibleness of hash-chain to the location-aided routing protocols, this mechanism can realize immediate incentive to the anonymous forwarders. Moreover, this mechanism can optimize the routing discover process through a route selection mechanism based on the payment price. The anonymity analyses indicate this mechanism can guarantee the anonymities of the nodes involved in routing. The performance evaluation shows that this mechanism has little effect on the routing performance when large amounts of data are transferred, and it is more efficient in small scale networks.


PubMed | Military School of Engineering, Academy of Military Science and Huaiyin Normal University
Type: | Journal: Journal of theoretical biology | Year: 2016

Multiple epidemiological models have been developed to model the transmission dynamics of Ebola virus (EBOV) disease in West Africa in 2014 because the severity of the epidemic is commonly overestimated. A compartmental model that incorporates the media impact and the effect of infected bats was constructed and calibrated using data reported until the end of 2014. The final cumulative number of deaths and confirmed cases were estimated to be 1.092110


Zi-Guang C.,Academy of Military Science | Li-Ping J.,Wuhan Naval University of Engineering | Jian-Chong Z.,Wuhan Naval University of Engineering | Shao-Wu G.,Air force Radar Academy
Lecture Notes in Electrical Engineering | Year: 2012

A serial of new issues need to be tackled before Ad Hoc network is used in military. There are many challenges: the lack of simulation platform of military Ad Hoc network, the difficulty of concept demonstration on maneuver combat, the hardness of quantitative analysis, etc. So, simulation system on maneuver combat is designed; frame and structure of the system are given. Many new issues on maneuver combat are researched: responsibility area programming, maneuver area programming, maneuver route programming, combat capability assessment, etc. This simulation system has a good application foreground. It can raise the cooperation capability of many single weapons. It can strengthen the capability of associated systems. © 2012 Springer-Verlag GmbH.


Dong X.-L.,Academy of Military Science | Sun J.-B.,Air Force Commander College | Sun N.-X.,Academy of Military Science
Xitong Fangzhen Xuebao / Journal of System Simulation | Year: 2011

The relation of operational index and Effectiveness of BVR air combat was explored. Firstly, key effectiveness index was screened out by (Sequential Bifurcation, SB). Secondly, based on design technology and the index analysis of discrete effectiveness space, interactive effect and main effect of factors were analyzed through the specific method of effectiveness index simulation experiment factor design of 2 k and n k. Multidimensional data analysis of the simulation factor n k was accomplished by the OLAP analysis technical. Finally, adopting exploratory simulation experiment method, demand locus of effectiveness index which secured victory with definite probability was accomplished. A lot of important analysis conclusions were reached by these methods. It is hopeful that these conclusions can offer help for operational commander decision and program and analysis of the effectiveness index of weapon equipment system.


Cheng W.,Air Force Command College | Zhan X.,Academy of Military Science | Zhang S.,Air Force Command College
Proceedings - 2011 6th IEEE Joint International Information Technology and Artificial Intelligence Conference, ITAIC 2011 | Year: 2011

Security has become the key issue in the development of large-scale information system. Piling security products and security technologies simply rather than functional integration and making full use of these products and technologies will cause resource wasting, and not meet the needs for flexible and diverse security requirements. This paper proposes a security architecture design based on SOA. Firstly, security devices and technologies are decomposed into basic security components which form the basic security service layer. Secondly, various extended security components that make up the extended security service layer are realized based on functional combination and process control. Then security services are provided through these two levels for upper security applications. At last, this paper gives the core architecture design of the security service core for dealing with the scalability bottlenecks in distributed system. The design solves effectively the security of large-scale information system. © 2011 IEEE.


Wu Y.,309th Hospital of Chinese | Jia J.,Academy of Military Science | Wang H.,309th Hospital of Chinese
Proceedings - 2014 IEEE Workshop on Electronics, Computer and Applications, IWECA 2014 | Year: 2014

To meet the requirements of OSGi distributed processing capabilities from enterprise computing, this paper proposes a convenient way which adds distributed computing capability to OSGi framework and supports interoperation between OSGi and legacy CORBA applications. This is achieved by using CORBA dynamic technology which implements the remote service invocation capability and CORBA naming service which supports remote service discovery capability. In the end, this paper proves the distributed processing capabilities by testing our implementation in a simple scenario with a legacy CORBA application. © 2014 IEEE.

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