Name: 
ZHANG Yingjun Angela
Title ( post ): 
Professor
Department: 
Information Engineering
email: 
yjzhang [at] ie.cuhk.edu.hk
phone: 
3943 8465
website: 
http://www.ie.cuhk.edu.hk/people/yjzhang.shtml
Area of expertise: 
Wireless Communications and Networking
Avatar: 
Class: 
faculty_member
Chinese Name: 
張穎珺
glossary_index: 
Z
Research Area: 
Wireless Communication, Network Economics

CUHK Develops Novel Tree Guard Monitoring System to Safeguard Invaluable Trees and Monitor Collapse Risk

Date: 
2014-10-28
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Two professors of The Chinese University of Hong Kong (CUHK), Prof. CHIU Siu Wai, School of Life Sciences and Prof. CHENG Chun Hung, Department of Systems Engineering and Engineering Management, have jointly developed an innovative ‘Tree Guard Monitoring System’, with a sponsorship from the Chung Chi College. The automatic monitoring system allows round-the-clock surveillance against possible tree theft, as well as risk of collapse for tilt and sick trees.  The system can be adopted by country parks, property managements as well as garden managements.  The novel system will be exhibited at the InnoCarnival 2014 to be held next month. 

As early as the Song Dynasty, farmers in Hong Kong planted Incense trees for producing and exporting fragrant products. The precious Incense trees have been in high demand, especially among the illegal traffickers in the mainland.  The endangered and vulnerable Incense trees are conserved by The State Council of China as a national protection wild plant (second class).  In Hong Kong, thefts of Incense trees, as well as the Buddhist Pine, another precious species known as the ‘Fung Shui’ tree, have been very frequent recently.  The incidents have prompted Prof. CHIU Siu Wai and Prof. CHENG Chun Hung, with a team of CUHK students and staff (including Mr. Stanley LO and Mr. Sam HUNG from the Department of Systems Engineering and Engineering Management), to develop the novel ‘Tree Guard Monitoring System’ to protect the plants, as well as to monitor the collapse risk of hazardous trees. 

The ‘Tree Guard Monitoring System’ consists of multiple sensors, such as sonic, temperature, humidity and tilt sensors, which are integrated into a hardware device with wireless communication capabilities for continuous monitoring. When the device is mounted on the tree, alerts will be sent to the control room when abnormal activities on the trees, such as sawing and hammering are identified. The same principles can be applied to monitoring tilt and sick trees.  

The natural environment is complicated and ever changing. For instance, a storm may destroy the devices, and minor movement may trigger the alarm system.  Therefore it is a great challenge for the researchers to develop a robust system with the least chance of false alarms.  Nonetheless, Mr. Lo and Mr. Hung insisted on carrying on the research and development of the system. 

Prof. CHENG Chun Hung explains, ‘The “Tree Guard Monitoring System” utilizes various wireless technologies to form a scalable wireless mesh network for transmitting sensor data to the control center.  The wireless communication network can be scaled up for wider coverage in two dimensions: 1) expansion within a tree group with  low-bandwidth, low-energy wireless communication; and 2) extending the coverage in multiple tree groups with Wi-Fi network communication, which should be readily available in many private premises and government facilities.’ 

Prof. CHIU Siu Wai said, ‘The system can provide useful real-time data for the tree management teams to devise proactive and reactive measures for safeguarding trees. In future, we also hope to set an early warning mechanism for trees with collapse risk, so that preventive measures can be carried out as early as possible to avoid accidents and casualties.’ 

Albeit difficult, Professor Chiu and Prof. Cheng still deemed it worthwhile to develop the system for protecting the trees and people’s lives. CUHK has been actively undertaking tree management research and offering recommendations to the authorities.  In October 2010, Prof. CHIU Siu Wai urged the government to formulate a sustainable tree strategy and establish a tree health database in Hong Kong to improve the effectiveness of tree management.  She has developed two novel tree management skills—‘paint coating’ and ‘micro-drill sampling’, which can help prevent trees from dying due to pest infestations, prevent Incense trees from producing resin, as well as detect hidden tree diseases and structural defect at an early stage.  Professor Chiu has held five different ‘Tree pests and treatment workshops’, in which various experts introduced common tree diseases, controlling strategies for sick trees, and shared tree management experience. Participants could learn and practise on-site during the workshop.

CUHK’s participation in InnoCarnival 2014

CUHK will participate in the InnoCarnival 2014, organized by the Innovation and Technology Commission of the Hong Kong Special Administrative Region Government, from 1 to 9 November at the Hong Kong Science Park.  Eighteen innovative projects developed by CUHK researchers will be showcased to inspire youngsters’ interest in science, engineering and mathematics.

Members of the public are welcome to visit CUHK’s booth at the InnoCarnival 2014, to learn more about the Tree Guard Monitoring technology and other recent innovative projects. Interactive games are also available to deepen visitors’ knowledge of the showcased projects.

Date: 

1 to 9 November 2014

Time:

10:00 am to 7:00 pm

Venue:

Convention Centre 3, 1/F., 12W, Phase 3, Hong Kong Science Park, Sha Tin

Website of InnoCarnival 2014: http://www.itm.gov.hk/

The research team led by Prof. CHIU Siu Wai (3rd right), School of Life Sciences, and Prof. CHENG Chun Hung (3rd left), Department of Systems Engineering and Engineering Management, has jointly developed an innovative ‘Tree Guard Monitoring System’.

 

The ‘Tree Guard Monitoring System’ allows round-the-clock surveillance against possible tree theft, as well as risk of collapse for tilt and sick trees.

 

 

CUHK Develops Novel Tree Guard Monitoring System to Safeguard Invaluable Trees and Monitor Collapse Risk

Alumnus Tak-Sing Wong Named One of the World's Top 35 Innovators

Date: 
2014-09-17
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Carnivorous plant inspires solution to “sticky” problems

The distinguished alumnus from Department of Mechanical and Automation Engineering was recently been selected as one of the world's top 35 innovators under 35 by MIT Technology Review in recognition of his achievement in inventing one of today’s most intriguing and potentially useful new materials. Called SLIPS, for “slippery liquid–infused porous surface,” it repels any type of liquid, from oil to water to blood, and prevents organisms like bacteria and barnacles from sticking.

The range of possible applications for the new material is wide: it could be used to coat medical devices such as catheters to decrease the potential for bacterial contamination or cover the hull of a ship to prevent barnacles from adhering to the surface.

Working at the Wyss Institute for Biologically Inspired Engineering at Harvard University, Wong modeled the SLIPS material after the carnivorous pitcher plants Nepenthes, which produce a surface that can upend even the oily feet of an ant and send the bug hydroplaning into the stomach of the plant. He assembled micro- and nanoscale structures and filled the empty spaces within the structures with a lubricant that repels both liquids and solids, including ice and bacterial biofilm.

He is now an assistant professor of mechanical engineering at Pennsylvania State University.

From www.technologyreview.com/lists/innovators-under-35/2014/

 

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MAE

Engineering Research on Privacy and Security in Online Social Networks

Date: 
2014-09-15
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Online Social Networks (OSN), like Facebook, Twitter and LinkedIn, has become an essential part of our daily life. We use them to maintain connections with our friends and get useful information. Besides, we use a lot of 3rd party Apps for amusement or additional functionalities. OSN users must authorize those Apps to access their own data objects, like statuses and photos. This is done via a widely adopted Single-Sign-On protocol called “OAuth 2.0”.

Although various OAuth 2.0 related vulnerabilities have been discovered recently, to our best knowledge, such vulnerabilities are all due to the improper application of OAuth. It was generally believed that the correct use of OAuth 2.0, e.g. by adhering to the guidelines provided in the Internet standards, is secure enough.

However, recent research by Prof. Wing Cheong Lau and his graduate students Mr. Pili Hu and Mr. Ronghai Yang shows that Department of Information Engineering of CUHK shows that OAuth 2.0 is intrinsically vulnerable to a type of so-called application-impersonation-attacks due to OAuth’s provision of multiple authorization flows and token types. Since different applications may have different privileges like access permission rights and rate limits, application impersonation would allow unauthorized privilege escalation. This, in turn, can result in large-scale privacy leaks, as well as the delivery of unauthorized notification messages to the mass. The team’s discovery shows that it is urgent for industrial practitioners to review their API design and enable applications to opt-out from certain specific modes of OAuth2.0 operation. This research also highlights the importance to protect the application as well as the user during the design of the next version of OAuth or other similar Single-Sign-On protocols. The work will be published in the ACM Conference on Online Social Networks (COSN’14) in Oct 2014. In the same conference, this MobiTeC team will also introduce a model-based testing tool which can automatically scan and audit OAuth deployments in practice. Back in August, the team had already presented their early findings to a large audience of cybersecurity practitioners and researchers in the BlackHat USA 2014 conference.

A related interview (http://www.weibo.com/1737187942/BmulJflhP?mod=weibotime)
can be found at: http://v.ifeng.com/news/tech/201409/01214414-b601-4604-be4e-1be3d04b62f7.shtml

 

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NCEL Develops New Business Model to Make Broadband Wireless Services Economical and Sustainable

Date: 
2014-09-11
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The Network Communications and Economics Lab (NCEL) led by Prof. Jianwei Huang, Department of Information Engineering, The Chinese University of Hong Kong (CUHK), has recently proposed a novel information market model for utilizing idle TV white space spectrum, which can bring a significant profit to the white space database operator, while guaranteeing mobile users' high quality wireless communication service. This work won the Best Paper Award in IEEE WiOpt 2014 (http://www.wi-opt.org), a single-track leading wireless conference focusing on modeling and optimization of wireless networks.

In most places, radio spectrum is allocated by strict licensing to different wireless applications. Driven by the explosive growth in smartphones and bandwidth-hunger applications, radio spectrum is becoming an increasingly scarce resource. It is becoming increasingly challenging for the current 3G/4G cellular network to fully satisfy the fast growing demands. Many countries have been trying to utilize the unused or under-utilized TV broadcast frequency channels (TV white space) to provide the so-called super Wi-Fi services. Comparing with today's traditional Wi-Fi technology, super Wi-Fi can extend the coverage to several to tens of kilometers. For example, a single super Wi-Fi base station with 30km coverage radius can cover an area of 2,000 CUHK campus. Regarding the transmission data rates, the current Wi-Fi technology can support a transmission rate of 5Mbps/MHz at a distance of 35 meters in an indoor environment. The super Wi-Fi can achieve the same indoor transmission rate at a distance of several hundreds. Moreover, due to the strong penetration capability of the super Wi-Fi technology, it can significantly improve communication qualities of smart meters and smart appliances, and facilitate large-scale deployments of new technologies such as M2M (machine to machine) and D2D (device to device) communications.

Today, countries such as USA, UK, and Singapore have been very active in developing database-assisted TV white space network trials. There is also a sizable amount of TV white space in Hong Kong, although how it should be used is still under discussion. Recently, the local regulator, the Office of the Communications Authority (OFCA), has claimed that the government would auction off a third of the 3G spectrum currently held by city's incumbent 3G mobile network operators. This results in customers' concerns in the potential deterioration of mobile communication service quality. Exploring the use of TV white space is one of the most effective solutions for alleviating the tension between limited network capacity and fast growing customer demands.

However, in contrast to the fast technology development of TV white space networking, the development of business models for this new network architecture is significantly lagging behind. Obviously, the lack of full understanding of such a business model will hamper the commercialization of TV white space network. Through the study of new business models of TV white space networks, Prof. Jianwei Huang and his team hope to increase the utilization of TV white space, provide new business opportunities to wireless service providers, and reduce the cost for the wireless consumers.

The Business Model for TV White Space: Trade Information, Not Spectrum

In most recently proposed business models for wireless spectrum, the unlicensed spectrum users need to purchase short-term usage rights from the licensed holders in a secondary spectrum market. However, TV white space is often defined as public goods, which do not have licensed owners and cannot be directly traded. In order to tackle this challenge, the CUHK research team proposed a new business model – the information market – to trade the network information related to TV white space channels instead of the channels themselves. Accordingly to the latest TV white space technology standards, an unlicensed spectrum user needs to inquire an authorized TV white space database regarding the available white space channels, and selects one channel for its communications. This is similar as today's mobile phones' process of searching for wireless networks. In the information market model proposed by Prof. Jianwei Huang and his team, the unlicensed users can also choose to purchase information from the spectrum database regarding the white space channels. Such information includes not only the basic information regarding the availabilities of channels, but also the advanced information regarding channel quality and interference level of each channel. With such information, the unlicensed spectrum user can choose a high quality white space channel for its communications, hence avoiding significant interferences from other mobile devices and maximizing the communication quality.

Through the information market model proposed by the CUHK NCEL team, the mobile users are able to freely choose between the free basic service and the premium information service when utilizing the TV white space channels. The TV spectrum database operators are able to make revenue through selling the advanced information, hence achieving a win-win situation. Such an information market business model can be directly applied to the current TV white space technology framework, without requiring additional investment in hardware.

About Network Communications and Economics Lab (NCEL)

The Network Communications and Economics Lab (NCEL) was formed in 2007 by Prof. Jianwei Huang in the Department of Information Engineering, focusing on the interdisciplinary research among communications, networking, and economics. The NCEL team has published over 160 papers in top international journals and conferences, with a total citation of more than 4,100 times. The NCEL's research results have received 7 Best Papers Awards in international venues, including the 2011 IEEE Marconi Prize Paper Award in Wireless Communications from IEEE Communications Society and IEEE Signal Processing Society. Four papers from NCEL are among the ESI Highly Cited Papers in the field of Computer Science, which are the 1% top papers in terms of citations within the field according to Essential Science Indicators from Web of Science.

The co-authors of this awarding winning work also include Ms. Yuan Luo and Dr. Lin Gao. Ms. Luo is a PhD student under the supervision of Prof. Jianwei Huang, and received the prestigious Hong Kong PhD Fellowship from Hong Kong Research Grant Council in 2011, with a monthly award of HKD20,000 for three years. Dr. Lin Gao is a Postdoc Research Fellow in CUHK, and received the Best Paper Awards from IEEE WiOpt in both 2014 and 2013. For more information, please see http://jianwei.ie.cuhk.edu.hk.

 

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CUHK Faculty of Engineering Researchers Develop New Business Model to Make Broadband Wireless Services Economical and Sustainable

Date: 
2014-09-10
Thumbnail: 
Body: 

The Network Communications and Economics Lab (NCEL) led by Prof. Jianwei Huang, Department of Information Engineering, The Chinese University of Hong Kong (CUHK), has recently proposed a novel information market model for utilizing idle TV white space spectrum, which can bring a significant profit to the white space database operator, while guaranteeing mobile users' high quality wireless communication service. This work won the Best Paper Award in IEEE WiOpt 2014 (http://www.wi-opt.org), a single-track leading wireless conference focusing on modeling and optimization of wireless networks. 

In most places, radio spectrum is allocated by strict licensing to different wireless applications.  Driven by the explosive growth in smartphones and bandwidth-hunger applications, radio spectrum is becoming an increasingly scarce resource. It is becoming increasingly challenging for the current 3G/4G cellular network to fully satisfy the fast growing demands. Many countries have been trying to utilize the unused or under-utilized TV broadcast frequency channels (TV white space) to provide the so-called super Wi-Fi services. Comparing with today's traditional Wi-Fi technology, super Wi-Fi can extend the coverage to several to tens of kilometers. For example, a single super Wi-Fi base station with 30km coverage radius can cover an area of 2,000 CUHK campus. Regarding the transmission data rates, the current Wi-Fi technology can support a transmission rate of 5Mbps/MHz at a distance of 35 meters in an indoor environment. The super Wi-Fi can achieve the same indoor transmission rate at a distance of several hundreds. Moreover, due to the strong penetration capability of the super Wi-Fi technology, it can significantly improve communication qualities of smart meters and smart appliances, and facilitate large-scale deployments of new technologies such as M2M (machine to machine) and D2D (device to device) communications. 

Today, countries such as USA, UK, and Singapore have been very active in developing database-assisted TV white space network trials. There is also a sizable amount of TV white space in Hong Kong, although how it should be used is still under discussion. Recently, the local regulator, the Office of the Communications Authority (OFCA), has claimed that the government would auction off a third of the 3G spectrum currently held by city's incumbent 3G mobile network operators. This results in customers' concerns in the potential deterioration of mobile communication service quality. Exploring the use of TV white space is one of the most effective solutions for alleviating the tension between limited network capacity and fast growing customer demands.

However, in contrast to the fast technology development of TV white space networking, the development of business models for this new network architecture is significantly lagging behind. Obviously, the lack of full understanding of such a business model will hamper the commercialization of TV white space network. Through the study of new business models of TV white space networks, Prof. Jianwei Huang and his team hope to increase the utilization of TV white space, provide new business opportunities to wireless service providers, and reduce the cost for the wireless consumers.

The Business Model for TV White Space: Trade Information, Not Spectrum

In most recently proposed business models for wireless spectrum, the unlicensed spectrum users need to purchase short-term usage rights from the licensed holders in a secondary spectrum market. However, TV white space is often defined as public goods, which do not have licensed owners and cannot be directly traded. In order to tackle this challenge, the CUHK research team proposed a new business model – the information market – to trade the network information related to TV white space channels instead of the channels themselves. Accordingly to the latest TV white space technology standards, an unlicensed spectrum user needs to inquire an authorized TV white space database regarding the available white space channels, and selects one channel for its communications. This is similar as today's mobile phones' process of searching for wireless networks. In the information market model proposed by Prof. Jianwei Huang and his team, the unlicensed users can also choose to purchase information from the spectrum database regarding the white space channels. Such information includes not only the basic information regarding the availabilities of channels, but also the advanced information regarding channel quality and interference level of each channel. With such information, the unlicensed spectrum user can choose a high quality white space channel for its communications, hence avoiding significant interferences from other mobile devices and maximizing the communication quality. 

Through the information market model proposed by the CUHK NCEL team, the mobile users are able to freely choose between the free basic service and the premium information service when utilizing the TV white space channels. The TV spectrum database operators are able to make revenue through selling the advanced information, hence achieving a win-win situation. Such an information market business model can be directly applied to the current TV white space technology framework, without requiring additional investment in hardware. 

About Network Communications and Economics Lab (NCEL)

The Network Communications and Economics Lab (NCEL) was formed in 2007 by Prof. Jianwei Huang in the Department of Information Engineering, focusing on the interdisciplinary research among communications, networking, and economics.  The NCEL team has published over 160 papers in top international journals and conferences, with a total citation of more than 4,100 times. The NCEL's research results have received 7 Best Papers Awards in international venues, including the 2011 IEEE Marconi Prize Paper Award in Wireless Communications from IEEE Communications Society and IEEE Signal Processing Society. Four papers from NCEL are among the ESI Highly Cited Papers in the field of Computer Science, which are the 1% top papers in terms of citations within the field according to Essential Science Indicators from Web of Science. 

The co-authors of this awarding winning work also include Ms. Yuan Luo and Dr. Lin Gao. Ms. Luo is a PhD student under the supervision of Prof. Jianwei Huang, and received the prestigious Hong Kong PhD Fellowship from Hong Kong Research Grant Council in 2011, with a monthly award of HKD20,000 for three years. Dr. Lin Gao is a Postdoc Research Fellow in CUHK, and received the Best Paper Awards from IEEE WiOpt in both 2014 and 2013. For more information, please see http://jianwei.ie.cuhk.edu.hk.

Prof. Jianwei Huang, Department of Information Engineering, CUHK (left) and his PhD student Ms. Yuan Luo.

 

(From left) The information market model for TV white space networks proposed by Prof. Jianwei Huang, Ms. Yuan Luo, PhD student, and Dr. Lin Gao, Postdoc Research Fellow won the Best Paper Award in IEEE WiOpt 2014.

 

The information market model for TV white space networks.

 

白頻譜網絡資訊巿場模型

 

 

CUHK Faculty of Engineering Researchers Develop New Business Model to Make Broadband Wireless Services Economical and Sustainable

Prof. Jun Wang Won an IEEE Neural Networks Pioneer Award

Date: 
2014-09-10
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The biennial IEEE World Congress on Computational Intelligence was held in Beijing on July6-11, 2014. Several awards such as Neural Networks Pioneer Award, Fuzzy Systems Pioneer Award, and Evolutionary Computation Pioneer Award were given at the awards banquet. Prof. Jun Wang from the CUHK’s Faculty of Engineering has won the Neural Networks Pioneer Award conferred by the IEEE President-elect, for his outstanding achievements on neurodynamic optimization.

Started in 1991, Neural Networks Pioneer Award is considered as the highest honor in the field of neural networks, to commemorate the outstanding contributions of some prominent scientists. Professor Wang is the third awardee in Asia to receive this honor following two professors at the University of Tokyo and Osaka University.

 

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Undergraduate Summer Research Internship 2014

Date: 
2014-09-09
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The following students are selected to receive the Best Project Awards.

1. Wong Yau Chun (BME) 黃友俊

Bacterial cellulose regenerated fiber
Supervised by Prof Douglas Yung

2. Li Linkai (EE) 李林鍇
Impedance Spectroscopy of Perovskite Solar Cells
Supervised by Prof Zhao Ni

3. Huang Jian (MAE) 黃戩
Microencapsulation and magnetic manipulation for cell delivery
Supervised by Prof Zhang Li

4. Liang Jiaxin (IE) 梁嘉炘
Programmable Intelligence for Cross-platform Socialization (PIXS)
Supervised by Prof Wing Lau

5. Zhang Qiaosheng (IE) 張喬生
Network Error-Correcting Codes
Supervised by Prof Sidharth Jaggi

6. Zhang Qiming (IE) 張启明
Distributed Backoff Protocols for Decentralized Social Networks
Supervised by Prof Wing Lau

 

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