AIRCRAFT FLIGHT SAFETY ANALYSIS IN LOW ALTITUDE AIRSPACE

The low altitude airspace will be open in China, general aviation flights are tremendously increased. Whether aircrafts can fly safely and how to determine the requirements of safety flight are the problems needed to be confirmed. Under this circumstances, based on the international Civil Aviation Organization（ICAO） criteria and the standards made by CAAC, this paper adopts the ＂See and Avoid＂ principle. Under the binding conditions of flight rules, visibility requirements, responding time, the aircraft speed, circle banking angle or the climbing angle, based on its study on aircraft dynamics principles, this paper establishes a mathematical collision avoidance model for head-to-head traffic and crossing converging traffic at the same level. And the safety separation requirements of the aircrafts in low altitude flight are equantitatively analyzed. Finally, the Matlab software is used to analyze the above method. The result shows that the safe traffic avoidance of the converging traffic at the same level meets certain flight conditions, while intersecting the traffic at the same level can safely avoid the collision.

技术融合下的D^2SMP网络

近年来,随着带宽的不断增加,对于网络的管理也通过新技术的出现而不断加强。不过,随着融合的不断发展,网络的管理与安全问题再一次凸显出来。在人们的日常生活和工作中,网络已经成为重要的基础设施,ERP、CRM等标志着企业竞争力的关键系统,都是在网络平台上运行的。可以说,离开了网络,企业在现代商业社会中的生存是无法想象的。因此,网络的安全、智能、可运营是保证企业生存的关键。

A New Design and Implementation of an Attendance Checking Node for Coal Mines

A novel design and implementation of an attendance checking node for coal mines based on the CAN bus is presented in this paper. Hardware circuits and programming methods for the attendance checking node are discussed,including the single-chip computer with CAN controller AT89C51CC03,the CAN bus transceiver TJA1050,the large capacity DataFlash memory,the real-time clock DS1302,the voice chip ISD2560 and the card-reading circuit in Wie-gand format. All the extended hardware satisfies the requirements for intrinsically safe circuits (GB3836.4-2000) and intrinsically safe authentication promoted by the national explosion-proof institute. Further,the software programming methods for the CAN controller (AT89C51CC03) and the implementation of the CAN communications protocol are presented as well.

Assessment of the Ecological Security in the Three Gorges Reservoir Area by Using the Ecological Footprint Method

The ecological footprint concept and its calculation models are useful for the measurement of the sustainable level of social and economic development.The ecological security situation of the Three Gorges Reservoir Area(TGRA) was evaluated using this concept in this study.The construction of the Three Gorges Reservoir has led to the change in the ecology and immigration status of TGRA.The ecological footprint method is an important means to study the regional ecological security.Our results suggested that,by excluding the areas for biodiversity conservation(12% of the total land),the ecological footprint per capita was 0.57895 ha,which exceeded the ecological carrying capacity in TGRA.The total ecological deficit was found to be 11,522,193.34 ha,accounting for 95.02% of the ecological carrying capacity.These findings suggested that the ecological security of TGRA was not good.In order to compensate for the ecological deficit,it was essential to introduce natural resources from other regions.

Role of street patterns in zone-based traffic safety analysis

Although extensive analyses of road segments and intersections located in urban road networks have examined the role of many factors that contribute to the frequency and severity of crashes, the explicit relationship between street pattern characteristics and traffic safety remains underexplored. Based on a zone-based Hong Kong database, the Space Syntax was used to quantify the topological characteristics of street patterns and investigate the role of street patterns and zone-related factors in zone-based traffic safety analysis. A joint probability model was adopted to analyze crash frequency and severity in an integrated modeling framework and the maximum likelihood estimation method was used to estimate the parameters. In addition to the characteristics of street patterns, speed, road geometry, land-use patterns, and temporal factors were considered. The vehicle hours was also included as an exposure proxy in the model to make crash frequency predictions. The results indicate that the joint probability model can reveal the relationship between zone-based traffic safety and various other factors, and that street pattern characteristics play an important role in crash frequency prediction.

A GIS Model for Analyzing Airspace Obstructions and Safety near Airports

The purpose of Federal Aviation Regulations Part 77, entitled ＂Objects Affecting Navigable Airspace＂, is to identify potential hazards and prevent adverse impacts to the safe and efficient use of navigable airspace. The OIS （obstruction identification surfaces） represent these regulations, identify objects that penetrate these imaginary surfaces, evaluate hazardous effects, and ensure safe separations of aircraft from obstructions. The OIS evaluation is often used for selecting airfield locations and runway orientations. More importantly, the OIS evaluation is an airport＇s safeguard against flawed urban development, especially for airports near rapidly expanding cities. Without accurate analysis tools, hand-calculation errors on the OIS can occur and cause adverse impacts to airport safety. Applying the GIS （geographic information system） features of geospatial data and 3D formats, this paper proposes a model named GIS Obstruction Model which is capable of precisely calculating maximum allowable heights and creating visual imagery of penetrating obstructions. The special features of the model include web-based design, adaptability to any airport, user-friendly multiple inquiry methods, quick response to online inquiries, and response with 3D visual reality. The proposed G1S Obstruction Model is useful for airport planning, architecture design, safety management or civil engineering permit review.

Secure Authentication of WLAN Based on Elliptic Curve Cryptosystem

The security of wireless local area network （WI.AN） becomes a bottleneck for its further applications. At present, many standard organizations and manufacturers of WLAN try to solve this problem. However, owing to the serious secure leak in IEEES02.11 standards, it is impossible to utterly solve the problem by simply adding some remedies. Based on the analysis on the security mechanism of WLAN and the latest techniques of WI.AN security, a solution to WLAN security was presented. The solution makes preparation for the further combination of WLAN and Internet.

Distributed Role-based Access Control for Coaliagion Application

Access control in multi-domain environments is one of the important questions of building coalition between domains. On the basis of RBAC access control model, the concepts of role delegation and role mapping are proposed, which support the third-party authorization. Then, a distributed RBAC model is presented. Finally the implementation issues are discussed.

Prediction of Instability Separation Modes and Its Application in Practical Dynamic Security Region

The transient critical boundary of dynamic security region (DSR) can be approximated by a few hyper planes correlated with instability separation modes. A method to fast predict instability separation modes is proposed for DSR calculation in power injection space. The method identifies coherent generation groups by the developed K-medoids algorithm, taking a similarity matrix derived from the reachability Grammian as the index. As an experimental result, reachability Grammian matrices under local injections are approximately invariant. It indicates that the generator coherency identifications are nearly consistent for different injections. Then instability separation modes can be predicted at the normal operating point, while average initial acceleration is considered as the measure of the critical generator group to amend the error. Moreover, based on these predicted instability separation modes, a critical point search strategy for DSR calculation is illustrated in the reduced injection space of the critical generators. The proposed method was evaluated using New England Test System, and the computation accuracy and speed in determining the practical DSR were improved.

Determination of Vitamins B2,B3,B6 and B7 in Corn Steep Liquor by NIR and PLSR

Corn steep liquor(CSL) is an important raw material that has high nutritional value and serves as a nitrogen source.Biotin in CSL is especially of great importance to fermentation.In order to develop a fast,versatile,cheap,and environmentally safe analytical method for quantifying vitamins B2(VB2),B3(VB3),B6(VB6) and B7(VB7) in CSL,the near-infrared spectroscopy(NIR) measurements of 66 samples(22 batches) of CSL were analyzed by partial least-square regression(PLSR).Multivariate models developed in the NIR regions showed good predictive abilities for VB2,VB3,VB6 and VB7.Results confirmed the probability of the multivariate spectroscopic approach as a replacement for expensive and time-consuming conventional chemical methods.

Safety Assessment for a Side-by-side Offloading Mooring System

In order to improve the safety properties of an offloading system with side-by-side （SBS） mooring in which the FPSO is moored by a yoke system in the field of BZ25-1, it is necessary to analyze those properties. According to the experience of similar projects, tow strategies of different offioading arrangements were discussed by using the 3-D radiation/diffraction theory and quasi-static time domain method to assess their respective safety properties. Through the safety assessment analysis of different arrangement comparisons, various ways to improve the safety properties of off＇loading systems with side-by-side mooring were verified by analyzing the tension in the mooring lines and the fender deflection. Through comparison it can be concluded that by enlarging the key factors properly, including the size of the fenders and the hawsers as well as the number of hawsers, a better safety performance can be achieved.

Research of data transmission security in videoconference system

Many coal enterprises have built the videoconference systems on their LAN （Local Area Network）. As the development of these enterprises, their organizations are distributed over our country and even over the world. Therefore, the videoconference systems have to run over WAN （Wide Area Network）. Normally, the structure of a videoconference system is center_division including MCU （multi control unit）and participants. No QoS and security assurance are available now because all videoconference system is based on TCP/IP. Therefore, the system stability is absolutely depended on the Network. This paper discussed how to anti ARP attacking. The method discussed in this paper is based on TCP/IP.

AUTHENTICATED SYMMETRIC-KEY ESTABLISHMENT FOR MEDICAL BODY SENSOR NETWORKS

This study concerns security issues of the emerging Wireless Body Sensor Network (WBSN) formed by biomedical sensors worn on or implanted in the human body for mobile healthcare appli-cations. A novel authenticated symmetric-key establishment scheme is proposed for WBSN,which fully exploits the physiological features obtained by network entities via the body channel available in WBSN but not other wireless networks. The self-defined Intrinsic Shared Secret (ISS) is used to replace the pre-deployment of secrets among network entities,which thus eliminates centralized services or au-thorities essential in existing protocols,and resolves the key transport problem in the pure symmet-ric-key cryptosystem for WBSN as well. The security properties of the proposed scheme are demon-strated in terms of its attack complexity and the types of attacks it can resist. Besides,the scheme can be implemented under a light-weight way in WBSN systems. Due to the importance of the ISS concept,the analysis on using false acceptance/false rejection method to evaluate the performance of ISS for its usage in the scheme is also demonstrated.

Evaluation of regional energy security in eastern coastal China based on the DPSIR model

The DPSIR assessment method, which implies the relationships among driving force （D）, pressure （P）, status （S）, impact （I）, and response （R）, is widely applied by scholars. This paper aims to establish a comprehensive assessment system for regional energy security in eastern coastal China based on the above model using different indicators. Factor analysis and the SPSS statistical analysis software were used to carry out scientific and quantitative assessments. The results indicated that con- tradictions of energy supply and demand as well as environmental pollution are the critical factors that present great challenges to regional energy security in this area. The authors argued that a sustainable, stable, and safe supply energy supply is crucial in solving the aforesaid dilemma, and improving the energy use efficiency is one of the best choices. Some countermeasures and suggestions regarding regional energy supply stability and utilization security were pointed out.

The White Volta Basin, Climate Change and Food Security： Perspectives of Riparian Communities in Northern Ghana

This paper has examined how the resources of the White Volta River are enhancing food availability for riparian communities in northern Ghana despite climate change and its associated effects on food security. Using participatory methods such as focus group discussions and interviews, data was collected from households and institutions in three riparian communities. The result of the study indicates that, all things been equal, cultivation of food crops along the river bank in the rainy season gives significantly high yields as compared to yields from farms farthest from the river under rain fed agriculture. Higher organic content and moisture retention capacity of river bank soils explains the yield differential and adaptability to climate change. In addition, farmers now irrigate cereal crops which were hitherto, reserved for only rainy season production. However, inappropriate irrigation practices are accelerating erosion and sedimentation of the river and thus, threaten the sustainability of agriculture and food security in the White Volta Basin. The paper therefore, recommends the adoption of IWRM （integrated water resources management） and the participation of local communities, Government and Civil Society organisations for sustaining the productive capacity of the White Volta Basin for enabling adaptation of agriculture to climate change in the riparian communities of the basin.

NATO and EU Strategies for the Black Sea Region： The Challenge of Power Balance in New Security Environment

The article gives an overview on the dynamic political processes in the Black Sea region after some major geostrategic changes posing instability concerns in the region. The aim is to summarise the policy tendencies of the international organisations （NATO and EU） towards Russia and to present some analytical thoughts on current Euro-Atlantic strategies. Proposed is a different way of thinking based on the ＂congagement＂ approach.

The rural economic development under the background of food security, resource allocation and regional coordination

From the background of new socialist countryside building, this paper proposes that the allocation of resources in rural areas is the organic combination of human resources in rural manpower on its possible configuration space, noting that effective human resource allocation in rural areas is of great significance to promote the moderately prosperous society building and to improve economic efficiency of human resources in rural areas and to increase farmers＇ income and so on ; Meanwhile, it analyzes the current situation and some problems of rural human resource allocation ; Finally, from the perspective of subject of human resources allocation in rural areas, it raises possible valid configuration path.

Modified electromagnetism-like algorithm and its application to slope stability analysis

In the view of the disadvantages of complex method (CM) and electromagnetism-like algorithm (EM), complex electromagnetism-like hybrid algorithm (CEM) was proposed by embedding complex method into electromagnetism-like algorithm as local optimization algorithm. CEM was adopted to search the minimum safety factor in slope stability analysis and the results show that CEM holds advantages over EM and CM. It combines the merits of two and is more stable and efficient. For further improvement, two CEM hybrid algorithms based on predatory search (PS) strategies were proposed, both of which consist of modified algorithms and the search area of which is dynamically adjusted by changing restriction. The CEM-PS1 adopts theoretical framework of original predatory search strategy. The CEM-PS2 employs the idea of area-restricted search learned from predatory search strategy, but the algorithm structure is simpler. Both the CEM-PS1 and CEM-PS2 have been demonstrated more effective and efficient than the others. As for complex method which locates in hybrid algorithm, the optimization can be achieved at a convergence precision of 1×10-3, which is recommended to use.

The planning and comprehensive utilization of Three Gorges Project

As the most significant water project,the Three Gorges Project (TGP) was designed to take care of multiple objectives for water utilization such as flood control,power generation and navigation.The implementation of the project improved the flood safety level of Jingjiang reach to more than 100-year return period,which reduced greatly the flood risk at the mid-lower reaches of Changjiang River,produce huge quantity of energy for the central,east and south China,and improved significantly the navigation conditions of Chuanjiang River.Meanwhile,the operation of the TGP in dry season which compensate the downstream water resources,will as well deepen the navigation channel and thus improve the navigation conditions in the middle river reach.With the increasing demands raised from various aspects of the society,new requirements will be made for the TGP for the purpose of harnessing,development and protection of the Yangtze River Basin.Therefore,it will be a long-term task for the operation of TGP on how to optimize the water resources utilization and implement an effective operation.

Orthogonal experiment design of EMI of security monitoring system in coal mines

Security monitoring system of coal mines is indispensable to ensure the safe and efficient production of colliery. Due to the special and narrow underground field of the coal mine, the electromagnetic interference can cause a series of misstatements and false positives on the monitoring system, which will severely hamper the safe production of coal industry. In this paper, first, the frequency characteristics of the interference source on the power line are extracted when equipment runs normally. Then the finite difference time domain method is introduced to analyze the effects of the electromagnetic interference parameters on the security monitoring signal line. And the interference voltage of the two terminal sides on the single line is taken as evaluating indexes. Finally, the electromagnetic interference parameters are optimized by orthogonal experimental design based on the MATLAB simulation on the normal operation of equipment.