A new low-cost demodulator for ZigBee receivers satisfying requirements of IEEE802.15.4 standard is presented,which is designed for ISM 2.4 GHz band and based on Zero-IF receivers.This demodulator extracts symbols dir...A new low-cost demodulator for ZigBee receivers satisfying requirements of IEEE802.15.4 standard is presented,which is designed for ISM 2.4 GHz band and based on Zero-IF receivers.This demodulator extracts symbols directly from baseband signal rather than recovering PN code chips,so its structure is simple.Two main techniques are used to improve the performance of demodulator.One is Phase-Axis Crossing Detector(PACD) which detects the phase correlation of baseband signal.The other is symbol synchronization and sampling clock correction algorithm.The result shows that this demodulator performance,Symbol Error Rate(SER) and Packet Error Rate(PER) meet IEEE 802.15.4TM standard requirements and the demodulator can handle frequency offset in excess of 200 kHz,involving a Zero-IF receiver with a Noise Figure(NF) lower than 17 dB,which is easily imple-mented in standard CMOS technology.展开更多
By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and spe...By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and speed during playing. The training method can be targeted to solve some common problems, and guide students to consciously feel the touch and the change of tone, listening with ears, controlling with fingers to achieve solid and soft balanced unity.展开更多
In view of the fact that consolidation area for supplementing prime farmland （CASPF） is a new concept proposed in the latest round of general land use planning in China, this paper proposes a new and integrated GIS-...In view of the fact that consolidation area for supplementing prime farmland （CASPF） is a new concept proposed in the latest round of general land use planning in China, this paper proposes a new and integrated GIS- based technology for delimiting CASPF. Taking the advantage of the features of CASPF, a comprehensive evaluation indicator system for defining ordinary farmland as CASPF is established in this study, which covers 11 indicators, including slope, land plots connectivity, altitude, surface soil texture, and so on. With the help of the ideal-point method, ordinary farmland plots are sorted according to their evaluation scores in descending order. Based on the space analysis technique of GIS, high-ranking land plots are defined as CASPF reasonably.展开更多
Teaching and research universities cultivate innovative talents that should have the following characteristics： a strong curiosity and thirst for knowledge, strong ability of self-learning and exploration. They shoul...Teaching and research universities cultivate innovative talents that should have the following characteristics： a strong curiosity and thirst for knowledge, strong ability of self-learning and exploration. They should primarily get engaged in applied basic research, focus on knowledge development and operational needs of the basic technology for logic systems, and acquire subject knowledge and expertise, technological innovation. They should have a good moral training, be able to work or live together with others; have good health and good human qualities, be able to take hard work. For the purposes of teaching and Research University, it is to foster innovative talents, we must adhere to the fundamental status of undergraduate teaching, and gradually promote the study of teaching; we must adhere to the path of industry-university cooperation; students in general education system must be established.展开更多
The paper introduces automotive safety cost formula, which defines the concept of private costs, technology costs and social costs and analyzes the impact of economic externalities in individual purchase decisions on ...The paper introduces automotive safety cost formula, which defines the concept of private costs, technology costs and social costs and analyzes the impact of economic externalities in individual purchase decisions on urban traffic safety in the private costs and discusses the concept of hard and soft technology and its function to improve vehicle safety. Take people, vehicles and the environment as the main line and points out the promoting role of the relevant state departments, policy, research institutions and transportation infrastructure in the social cost for the entire transportation system security. Finally, about the security of car crash in low speed on urban roads, the paper gives some recommendations as for private costs, technology costs and social costs factor.展开更多
In the paper the Czech toll system and its future are presented. E-toll Czech project： Facts and Figures （today） are included and the next steps in the process of developing microwave infrastructure are mentioned. ...In the paper the Czech toll system and its future are presented. E-toll Czech project： Facts and Figures （today） are included and the next steps in the process of developing microwave infrastructure are mentioned. In the event of possible system extension of the roads of the 1st, 2rid and 3rd class （ca 55,000 km）, the satellite technology will be used. The feasibility of such a combination of these two technologies, microwave and satellite, is subject to the compatibility of both systems in terms of the control equipment. For the microwave toll system, economic analyses according to EU directives were prepared for the Czech Ministry of Transport. Special attention is paid to the problems of traffic congestion, noise and damage to the environment, on the basis of the ＂user pays＂ and ＂polluter pays＂ according to the Eurovignette Directive principles. A complete survey of the EU toll system is included in the list of information sources.展开更多
基金Supported by Zhejiang Province Important Sci-Tech Foundation Item (No.2006C11107)
文摘A new low-cost demodulator for ZigBee receivers satisfying requirements of IEEE802.15.4 standard is presented,which is designed for ISM 2.4 GHz band and based on Zero-IF receivers.This demodulator extracts symbols directly from baseband signal rather than recovering PN code chips,so its structure is simple.Two main techniques are used to improve the performance of demodulator.One is Phase-Axis Crossing Detector(PACD) which detects the phase correlation of baseband signal.The other is symbol synchronization and sampling clock correction algorithm.The result shows that this demodulator performance,Symbol Error Rate(SER) and Packet Error Rate(PER) meet IEEE 802.15.4TM standard requirements and the demodulator can handle frequency offset in excess of 200 kHz,involving a Zero-IF receiver with a Noise Figure(NF) lower than 17 dB,which is easily imple-mented in standard CMOS technology.
文摘By analyzing several effective finger practices, it is possible to consolidate the basic skills to help students adjust and establish a good touch mode. This is an important pre-requisite for pursuing strength and speed during playing. The training method can be targeted to solve some common problems, and guide students to consciously feel the touch and the change of tone, listening with ears, controlling with fingers to achieve solid and soft balanced unity.
基金Supported by the National Natural Science Foundation of China （No.40701179） and the Fundamental Research Funds for the Central Universities （No. XDJK2009C 102）.
文摘In view of the fact that consolidation area for supplementing prime farmland （CASPF） is a new concept proposed in the latest round of general land use planning in China, this paper proposes a new and integrated GIS- based technology for delimiting CASPF. Taking the advantage of the features of CASPF, a comprehensive evaluation indicator system for defining ordinary farmland as CASPF is established in this study, which covers 11 indicators, including slope, land plots connectivity, altitude, surface soil texture, and so on. With the help of the ideal-point method, ordinary farmland plots are sorted according to their evaluation scores in descending order. Based on the space analysis technique of GIS, high-ranking land plots are defined as CASPF reasonably.
文摘Teaching and research universities cultivate innovative talents that should have the following characteristics： a strong curiosity and thirst for knowledge, strong ability of self-learning and exploration. They should primarily get engaged in applied basic research, focus on knowledge development and operational needs of the basic technology for logic systems, and acquire subject knowledge and expertise, technological innovation. They should have a good moral training, be able to work or live together with others; have good health and good human qualities, be able to take hard work. For the purposes of teaching and Research University, it is to foster innovative talents, we must adhere to the fundamental status of undergraduate teaching, and gradually promote the study of teaching; we must adhere to the path of industry-university cooperation; students in general education system must be established.
文摘The paper introduces automotive safety cost formula, which defines the concept of private costs, technology costs and social costs and analyzes the impact of economic externalities in individual purchase decisions on urban traffic safety in the private costs and discusses the concept of hard and soft technology and its function to improve vehicle safety. Take people, vehicles and the environment as the main line and points out the promoting role of the relevant state departments, policy, research institutions and transportation infrastructure in the social cost for the entire transportation system security. Finally, about the security of car crash in low speed on urban roads, the paper gives some recommendations as for private costs, technology costs and social costs factor.
文摘In the paper the Czech toll system and its future are presented. E-toll Czech project： Facts and Figures （today） are included and the next steps in the process of developing microwave infrastructure are mentioned. In the event of possible system extension of the roads of the 1st, 2rid and 3rd class （ca 55,000 km）, the satellite technology will be used. The feasibility of such a combination of these two technologies, microwave and satellite, is subject to the compatibility of both systems in terms of the control equipment. For the microwave toll system, economic analyses according to EU directives were prepared for the Czech Ministry of Transport. Special attention is paid to the problems of traffic congestion, noise and damage to the environment, on the basis of the ＂user pays＂ and ＂polluter pays＂ according to the Eurovignette Directive principles. A complete survey of the EU toll system is included in the list of information sources.
