Securing private wireless sensors in a shared environment in the internet of things context Anass RGHIOUI*1,Said BOUCHKAREN2,Anass KHANNOUS1,Mohammed BOUHORMA1 1LIST FSTT(Laboratory of Informatics,Systems and Telecommunications)
2LabTIC ENSAT(Laboratory of Technology of Information and Communication)
Abdelmalek Essaadi University
Tangier,Morocco
anass.rgh@https://www.doczj.com/doc/db14080544.html,
Abstract—To lead to the Smart Cities,we should have the possibility of obtaining information from different places and objects anytime and anywhere,in order to collect suf?cient data to anticipate problems and take a good decisions.This will promote to an effective and autonomous organization by creating interacted and communicated objects around the city. So,we need to install various and speci?c IP-based wireless sensors everywhere to collect data remotely and in a real time. The idea of mixing sensors belonging to organizations from different specialties in the same places will involve several experts and encourages competition.But on the other side,it will open the door to new security threats and issues,also this will impose new management problems like how to limit the access to each organization to its sensors.
In this paper,we study the security of a set of IP-based wireless sensors,which belongs to different organizations,and form a local network.We propose a model to ensure exchanged information con?dentiality and manage the sensors accessibility, while considering the wireless sensors constrained characteristics.
Keywords—Smart City;IEEE802.15.4;6LoWPAN;Internet of Things;IoT;WSN;Network Security.
I.I NTRODUCTION
With the immense and rapid development of technology, integrating different devices to the internet becomes possible. Communication interaction are transformed from human-to-machine to machine-to-machine(M2M),and more speci?cally things-to-things,that what create the Internet of Things(IoT) [1].
This technology progress facilitates the leading of smart cities[2],where different cohabited object can communicate and interact to decide instead of human,or to help managers to make more effective decisions.It supports the improvement on many life applications like logistic,healthcare,industry... etc.Mainly for monitoring requirement where we must use sensors devices to capture data in physical or environmental conditions.
Enabling wireless sensors based on the IEEE802.15.4 communication protocol[3],to connect to the internet by implementing them by6LoWPAN(IPv6over Low power Wireless Area Network)technology[4],[5],gives the possi-bility to transfer sensed data through the network in the entire world.6LoWPAN was developed by IETF as an adaptation layer between network layer and data link layer to pass IPv6 packet of1260bytes into802.15.4that support only127bytes frames.This solution allows the use of existing resources like internet protocols and infrastructure,and addressing a huge number of devices since an IPv6address is128bits long,this provides about3.4x1038addresses more than667million billion addresses per square millimeter of land surface.
Inasmuch as the Internet of Things is based on an open architecture[6],and the weaker characteristics of wireless sen-sors as resource-constrained devices,security issues becomes more sensitive.Attacks can come from two sides:802.15.4 side and IP side[7].Another issue is the security management in the case of implementing different sensors from different organization in the same place.In a normal situation,sensors belonging to the same organization form a local network managed by a base station,but in the IoT context,to give the opportunity for intervention from different experts and encourage concurrence,sensors from different origins should be cohabited in the same local area.
This paper provides a security model in the context of Inter-net of Things to ensure con?dentiality and access management of a set of IP-based wireless sensors,which belongs to different management agencies and form a local network.
The structure of the paper is as follows:Section2gives a brief overview of Smart Cities,IoT,6LoWPAN and IEEE 802.15.4and their main applications,Section3reviews the as-sumption and discusses the issues of our studied case security, Section4discusses the model for securing the network with the focus on key establishment schemes,Section5presents an analysis of our model in terms of energy,?exibility and security.Finally,Section6concludes the paper.
II.GENERAL CONTEXT
A.Smart Cities projects
Smart City is a set of interconnected systems collaborating together and using technology tools in order to offer a better city management https://www.doczj.com/doc/db14080544.html,ed tools are a whole of small con-nected devices accessed remotely.Interaction between them facilitate communications and offer better coordination.They form a working group with huge possibilities in monitoring, surveillance,and management giving real time data to man-agers and citizens to anticipate problems and have suf?cient information for better decisions.
Most of actors involved in such projects are industrial sectors of energy,water,transport,telecom network and in-
978-1-4799-5587-9/14/$31.00 ?2014 IEEE
frastructure companies,builders working on the hardware equipment of smart cities,integrators and services companies.B.Internet of Things concept
Internet of Things is a concept that aims to extend the internet to the real world by associating labels bearing codes,RFID tags or URLs to objects or places,making them available and accessible from anywhere and anytime.
Many technologies must be used and integrated to achieve this goal.Devices are different,some of them,like Wireless Sensor Network [8]are resource-constrained,they are not com-patible with internet communication protocols.These protocols must be adapted or new ones must be developed.
Applications domains include:waste management,urban planning,environmental sensing,social interaction gadgets,sustainable urban environment,continuous care,emergency response,intelligent shopping,smart product management,smart meters,home automation and smart events [9].C.6LoWPAN technology
6LoWPAN is a combination between the IPv6and IEEE 802.15.4,two totally different networks.The most important difference is the size of the IPv6packet measuring 1280bytes,where the 802.15.4supports only 127octet packets.The solution proposed by the IETF 6LoWPAN working group is to add an adaptation layer that optimizes IPv6packets through fragmentation and assemblies to be supported by the IEEE 802.15.4link layer (Figure
1).
Fig.1.6LoWPAN WSN layers and main protocols
6LoWPAN network consists of one or more stub networks connected to the internet through the Edge Router.This latter,called also Border Router,routes traf?c in and out of the LoWPAN,which is the collection of 6LoWPAN nodes sharing the same address pre?x IPv6,ie the ?rst 64bits,it is used with IID (Interface Identi?er)[10]to form the IP address.This address is formed using the SSA (Stateless Address Autocon?guration)[11]in the starting phase of the network construction:the bootstrapping.This phase is managed by the data link layer which allows the establishment of ?rst
communications between nodes to con?gure channel,security keys and addressing.
After the bootstrapping phase,and once the data link layer is functional,6LoWPAN Neighbor Discovery protocol [12]that was chosen instead of the Neighbor Discovery protocol [13]because of its incompatibility with the low-power wireless networks -is used to start the construction of the entire network through some messages exchanged between nodes that allow hosts,routers and Edge Router autocon?guration.
Because of routing issues in 6LoWPAN,another team was created,IETF-ROLL (Routing over Low-power and Lossy Network)working group,to seek a proper routing solution to this kind of networks.They propose RPL (Routing Protocol for Low-power and Lossy-networks)[14].It is a distance vector routing protocol for IPv6which constructs a Directed Acyclic Graph.It is implemented in route-over.D.IEEE 802.15.4standard
802.15.4is a family of ad hoc networks for low-resource devices known by their low power consumption,low range and low debit.IEEE 802.15.4protocol is implemented in the two lower layers,ie,data link layer and physical layer.It divides devices into two types:FFD (Full Function Device)with all possible functions,must be at least one in a network,it acts as a PAN coordinator or a router and can communicate with all devices within the same network.And RFD (Reduced Function Device)with limited functions,it acts as a sensor or actuator and can only communicate with FFDs [15].
802.15.4de?nes two types of topologies:star and mesh.In star topology,devices are placed in groups as clusters,each cluster is managed by a cluster-head.Into a cluster,devices communicate only with their cluster-head.Cluster-heads can communicate with each other.In mesh topology,all devices contribute to the formation of the network and every one communicates with others who are within his reach.
Star topology
Mesh topology
FFD (Full Function Device)
RFD (Reduced Function Device)
Fig.2.IEEE 802.15.4topologies
III.
ASSUMPTIONS
A.Case study
Among smart city projects is offering data accessibility from speci?c places,objects,machines or products via internet.For that,it was a need to set up a lot of sensors belonging to
different organizations,institutions or companies.Depending to the use even if they collect the same data,we must limit the access of each group of sensors to the organizations that they belong.We should implementing them by a security system that preserve the con?dentiality of sensed information,because every organization would like to have a limit and exclusive accessibility to its sensors.
In this case study,we suppose that it exists a 6LoWPAN WSN (Figure 3)where sensors of different organizations are placed in the same place and forming one local network,i.e.one LoWPAN.The network may be linked to the internet by one or several edge routers.These edge routers are linked by a common backbone link and all sensors in this network have the same IPv6pre?x.This LoWPAN is managed remotely by a remote
server.
Fig.3.6LoWPAN WSN architecture with a Remote Server and different organizations (Org.A and Org.B)
We suppose that the LoWPAN,more precisely the 6LoW-PAN WSN in our case,consists of following units:an edge router ER,routers and hosts.Each one of routers and hosts has a unique identi?er.Hosts do not communicate with each other.
All devices are located in the network in a distributed way,but no one is outside the reach of other network sensors.Thus,
each node is connected to at least one router.
The LoWPAN is managed from a distance by a remote server RS,it offers information and updates to the network sensors.It may play the role of the main base https://www.doczj.com/doc/db14080544.html,munications within the LoWPAN are of two types:communications exchanged between the sensors and the edge routers,and those exchanged between sensors themselves to establish links and update the network topology.Other communications are those intended for outside the LoWPAN,for responsible organizations or for a remote server.B.Suitable solution
To achieve data con?dentiality,we must keep secret ex-changed data between two devices,for that,we have to use cryptography.There is two types of cryptography,symmetric and asymmetric.In symmetric cryptography,both communi-cating parties must share the same security key.However,for asymmetric cryptography,each unit has two keys:a public one that attributes it to each device that needs to communicate with it,and a private one which keeps it secret,used to decrypt messages encrypted by the public key.The advantage of asymmetric cryptography is its managing security keys mechanism,instead of symmetric cryptography where the problem of how a device will share its key privately with the other one without being disclosed by unauthorized parties.Since energy conservation is an essential element in WSN networks,most of studies [1],[7],[15][18]recommends the use of symmetric cryptography because,unlike asymmetric cryptography,it implements algorithms that do not require a lot of calculation,as a bene?t,it does not consume a lot of energy.
The dif?cult task in symmetric cryptography is security key management since each sender must have the same shared key with the recipient to decrypt the encrypted messages.Both must have speci?c mechanism in order to exchange the security key without being unveiled by a malicious.
IV.
PROPOSED SOLUTION
The main purpose of this paper is not to offer a complete security solution for IP-based WSN,the aim of our study is to propose a general security model to resolve the con?dentiality issues:con?dentiality of transmitted information and con?den-tiality of accessing to the device.Our scheme can be adapted and implemented by any IP-based WSN as needed,depending on the used application,in the context of IoT,in order to establish a smart city project.
Our solution is based on symmetric cryptography,it offers three types of security keys:a pairwise key between the ER and the network nodes,a pairwise key between two nodes,and a group key shared by all nodes belonging to the same organization.Also,this solution manages pairwise nodes access from outside the LoWPAN.
To generate a key,a node use a seed S and its secret ID N ID i .The N ID i must not be shared in plaintext into the network.
The choice of the cryptographic algorithm and the method to which he will combine between S and N ID i to generate
TABLE I.
L IST OF USED NOTATIONS
ER Edge Router RS Remote Server
S Generated seed by RS S N i Generated seed by N i N i Node i
N ID i The ID of N i
K N i ER Pairwise key between N i and ER
K N i,j Pairwise key between two nodes N i and N i Org X Organization X (X may be A or B ...)K Org X Group key shared between Org X nodes L 1
Level of a node towards ER
the key,is left to the user according to his needs and his
deployment environment.
Communications between the edge routers,the remote server,and the organizations are well secured as they are powerful and robust machines.A.Predeployment con?gurations
In the RS,we create a database of the nodes that will be present in the network.This database is implemented by data concerning these devices.The two necessary information for our solution are the identi?er ID and the MAC address of each node.
Also,each ER in this network will be implemented by a database of nodes within the LoWPAN.This database will record for each node its addresses (MAC and IP)and its pairwise security key shared whith this node.
Every node N i has three types of security keys:K N i
ER a
pairwise key between N i and the ER,K N i,j
between two nodes N i and N j (between a host and a router,or between
two routers),and group key K Org
X
shared between all of nodes belonging to the same organization X.
B.Security keys establishment
In this section we explain the suggested methods for
the management and establishment of symmetric keys in the network:the shared pairwise key between the edge router and network nodes,the shared key between two communicated a node into the LoWPAN and the shared group key between the same organizations nodes.
1)K N i
ER establishment:The RS generates a seed S ,sends it to the ER of the LoWPAN that transfers it to the nodes in the ?rst row,the message is determined as a message of level L 1since it begins from the ER that represents the head of the network.A node N i receives this message,keeps the seed and increment the level in the received message as its level,so if the ?rst message that is sent by the ER equal to 1,the ?rst devices that receive this message will have L 2,and so on,each node that receives this message for the ?rst time will increment its level.Thus,each node records the one-hop sender address of this message as its gateway to the ER.Thereafter,each node send the received seed to other one-hop nodes,in this case:if a node has already received the seed,it will check the level of the sender,if it is less than or equal to its level,it will reject it,otherwise it will record the sender address as its second gateway.If a device receives the message for the ?rst time,it will proceed as cited before.So on,until all the
nodes in the network receives the seed S .This way,each node N i will use the S with its own ID N ID i to generate the secret
key K N i
ER .Since the
RS has the seed and all devices IDs in its database,it will generate for each one its appropriate security key and send them securely to the ERs each one with its MAC address.Upon receiving an encrypted message,ER will check the address of the sender to determine its key that will use to decrypt the message (Figure 4).
Fig.4.
K N
i ER establishment and sharing
2)K N i,j establishment:After that each node in the net-work has a symmetric key K N i
ER shared with the ER,they will need to communicate with each other to share some information and update their routing tables.For this,each device generates its own seed S N i and use it with its ID to generate a symmetric key K N i in order to share it with its neighbors.If a node N i wants to communicate with another N j ,one of them must be a router node.Firstly,they exchange hello messages,including their level.The node which has the level less than the other,that is to say it is in a position nearest to the ER,will deal with authentication procedures and key exchange.Assuming that N i level less than N j .In this case,N i records in a message N j MAC address and its own key
K N i ,encrypts this message by its key K N i
ER and transfers it to ER.The latter,i.e.the ER,decrypting this message will understand that the node owner of the address contained in the message,i.e.N j ,wants to communicate with the node sending the message,which is N i .The ER will check them by requesting RS.If it is OK,ER encrypts the sender node
key K N i with the solicited node key K N j
ER and sends it to this latter,i.e.N j to use it to communicate securely with the other node N i (Figure 5).
3)K Org X establishment:In our model,RS acts as a proxy between organizations and their nodes.Every organization that implements these sensors in the network must ?rst register them within the RS,it must provide sensors ID and MAC address.Through the database,the RS will identify each node by its owner,like that,each organization wants to communicate
+=Hello
Encrypts Nj MAC address and
by MAC ,)
( )S
N
i
S N i N i ID K
N i
+=N
K
N i K N i
ER
MAC
Addr
,K N i
( )K
N i
ER
( )
K N i K N j ER
Fig.5.
K N i,j establishment and sharing
with its nodes must ?rst pass through the RS.RS plays the
role of intermediary between the node and the organization.RS will verify the access authorization of this organization to this node.If it is OK,RS receives the sensor data through ER and forwards it after to this organization.In the case where an organization wants to make an order to its nodes,an update or a con?guration change to enhance security,we establish a group key with respect to each set of nodes belonging to the same organization.Each organization will generate a symmetric key K Org X and send it in a secure way to RS.This latter checks
this organization nodes and sends them the K Org
X
to each one encrypted by its symmetric key K N i
ER .
V.
D ISCUSSION OF TH
E PROPOSED SOLUTION
We evaluate our work relative to three criteria:energy ef?ciency,an essential element for LoWPAN networks,?exi-bility and scalability of this model in a dynamic network like distributed networks,and security our main objective of this study.
A.Energy ef?ciency
From energy point of view,which is an essential metric for LoWPAN networks,and a critical criterion of choice to adopt or not a solution,our model does not require a lot of calculation or data exchange between devices to establish security keys,it can be considered as an energy-economizer.
Our model is based on symmetric cryptography that is recommended by experts in the ?eld as an appropriate solution for LoWPAN.Our proposal for key management in our scheme has three key types to secure communication within this network:communication between the edge router,the remote
server and network nodes,and communication between nodes.
A node uses its own information such as the ID to establish the key,it does not store other additional information that will charge its space storage.In terms of computation,a device only needs to combine between the seed and its ID to generate the key,an operation that not require excessive computation.B.Flexibility and scalability
In distributed topologies,two elements are important to take into consideration,?exibility and scalability,we deal with this two concepts by modeling a schema that tolerates changes in topology and do not depend in a speci?c infrastructure.Our scheme is ?exible towards changes in:topology,nodes positions,and network density.Each node has a speci?c key sharing with the edge router,in any position,both can establish a secure communication using their shared key.A device can easily change a router by another,for route optimization,due to a malfunction of a node,a change of position,or for another reason,it will request the connection establishment with the new gateway,it has only to forward its request to the edge router for veri?cation and exchange keys.In the case of a new device that is added to the network,it must be previously added to the database of the remote server.Then,it has only has to send a request the nearest router to establish a connection in the same way mentioned above.C.Security metrics
Our solution ensures con?dentiality,authentication and authorization of communications in the network.
All communications and data exchanged in the network are encrypted,the only information exchanged in plaintext is the seed generated by the remote server that represents only one element among others that are well secured to establish the key.Thus,any node unless those de?ned in the Remote server has permission to join the network,or has the possibility of establishing a security key.
Also,no outsider device can communicate directly with a LoWPAN node,it must ?rstly pass by the remote server.And only authorized ones can communicate with network nodes,each one can receive only sensed data from its own sensors.We avoided any sharing of information that may present a risk to the network,the key generation is done in the node itself.Thus,we do not share in the network nodes IDs,so no intruder can take a legitimate device ID by a snif?ng attack.The remote server is a powerful and well secured machine,it was given the role of monitoring the network basing on the database of legitimate network devices.
VI.
C ONCLUSION
We presented a settlement security keys for symmetric cryptography in order to secure a 6LoWPAN-based Wireless Sensor Network in the context of the Internet of Things in the case where many organizations implement their sensor nodes in a shared environment.This model is based on the establishment of three security pairwise keys in order to secure communication between the remote server,edge router and network nodes.This model should ensure the con?dentiality and nodes authentication as no intruder cannot get a false
identity or set the security key to integrate the network.The discussion and the analysis showed that this scheme meets the measures that must be taken into account for6LoWPAN-WSN,such as energy conservation,and adaptation for network ?exibility and scalability.We have not de?ned any symmetric cryptography algorithms or a speci?c application utilization to let the choice to the user according to his needs.As future work,this model should be tested using different symmetric cryptographic algorithms with heterogeneous nodes to verify its effectiveness,and to the well-suited for practical use and in a real environment.
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网络营销参与与消费者行为外文翻译 本科毕业论文设计外文翻译原文 Internet Marketing Involvement and Consumer Behavior Introduction One of the most stunning aspects of the past few years has been the speed at which the Internet market has expanded and matured This rapid rate of Internet adoption has resulted in an extraordinary pace of change in the marketing landscape- and opened up a variety of opportunities for marketers All across Taiwan and around the world shopping centers are closing their doors as consumers turn to the Internet for all of their shopping needs The Internet as the primary on-line marketing channel is now overtaking the commercial on-line servicesIn fact all of the on-line service firms now offer Internet access as a primary service Users can send e-mails exchange views shop for products and access newsfood recipes art and business information As the Internet establishes its position as a mainstream marketing channel consumer criticism regarding Internet marketing strategies have increased as well Critics worry about information privacy including issues related to the acquisition and dissemination
中英文对照资料外文翻译文献 平设计任何时期平面设计可以参照一些艺术和专业学科侧重于视觉传达和介绍。采用多种方式相结合，创造和符号，图像和语句创建一个代表性的想法和信息。平面设计师可以使用印刷，视觉艺术和排版技术产生的最终结果。平面设计常常提到的进程，其中沟通是创造和产品设计。共同使用的平面设计包括杂志，广告，产品包装和网页设计。例如，可能包括产品包装的标志或其他艺术作品，举办文字和纯粹的设计元素，如形状和颜色统一件。组成的一个最重要的特点，尤其是平面设计在使用前现有材料或不同的元素。平面设计涵盖了人类历史上诸多领域，在此漫长的历史和在相对最近爆炸视觉传达中的第20和21世纪，人们有时是模糊的区别和重叠的广告艺术，平面设计和美术。毕竟，他们有着许多相同的内容，理论，原则，做法和语言，有时同样的客人或客户。广告艺术的最终目标是出售的商品和服务。在平面设计，“其实质是使以信息，形成以思想，言论和感觉的经验”。
在唐朝（618-906 ）之间的第4和第7世纪的木块被切断打印纺织品和后重现佛典。阿藏印在868是已知最早的印刷书籍。在19世纪后期欧洲，尤其是在英国，平面设计开始以独立的运动从美术中分离出来。蒙德里安称为父亲的图形设计。他是一个很好的艺术家，但是他在现代广告中利用现代电网系统在广告、印刷和网络布局网格。于1849年，在大不列颠亨利科尔成为的主要力量之一在设计教育界，该国政府通告设计在杂志设计和制造的重要性。他组织了大型的展览作为庆祝现代工业技术和维多利亚式的设计。从1892年至1896年威廉?莫里斯凯尔姆斯科特出版社出版的书籍的一些最重要的平面设计产品和工艺美术运动，并提出了一个非常赚钱的商机就是出版伟大文本论的图书并以高价出售给富人。莫里斯证明了市场的存在使平面设计在他们自己拥有的权利，并帮助开拓者从生产和美术分离设计。这历史相对论是，然而，重要的，因为它为第一次重大的反应对于十九世纪的陈旧的平面设计。莫里斯的工作，以及与其他私营新闻运动，直接影响新艺术风格和间接负责20世纪初非专业性平面设计的事态发展。谁创造了最初的“平面设计”似乎存在争议。这被归因于英国的设计师和大学教授Richard Guyatt，但另一消息来源于20世纪初美国图书设计师William Addison Dwiggins。伦敦地铁的标志设计是爱德华约翰斯顿于1916年设计的一个经典的现代而且使用了系统字体设计。在20世纪20年代，苏联的建构主义应用于“智能生产”在不同领域的生产。个性化的运动艺术在2俄罗斯大革命是没有价值的，从而走向以创造物体的功利为目的。他们设计的建筑、剧院集、海报、面料、服装、家具、徽标、菜单等。J an Tschichold 在他的1928年书中编纂了新的现代印刷原则，他后来否认他在这本书的法西斯主义哲学主张，但它仍然是非常有影响力。Tschichold ，包豪斯印刷专家如赫伯特拜耳和拉斯洛莫霍伊一纳吉，和El Lissitzky 是平面设计之父都被我们今天所知。他们首创的生产技术和文体设备，主要用于整个二十世纪。随后的几年看到平面设计在现代风格获得广泛的接受和应用。第二次世界大战结束后，美国经济的建立更需要平面设计，主要是广告和包装等。移居国外的德国包豪斯设计学院于1937年到芝加哥带来了“大规模生产”极简到美国;引发野火的“现代”
陶瓷 ceramics 合成纤维 synthetic fibre 电化学腐蚀 electrochemical corrosion 车架 automotive chassis 悬架 suspension 转向器 redirector 变速器 speed changer 板料冲压 sheet metal parts 孔加工 spot facing machining 车间 workshop 工程技术人员 engineer 气动夹紧 pneuma lock 数学模型 mathematical model 画法几何 descriptive geometry 机械制图 Mechanical drawing 投影 projection 视图 view 剖视图 profile chart 标准件 standard component 零件图 part drawing 装配图 assembly drawing 尺寸标注 size marking
技术要求 technical requirements 刚度 rigidity 内力 internal force 位移 displacement 截面 section 疲劳极限 fatigue limit 断裂 fracture 塑性变形 plastic distortion 脆性材料 brittleness material 刚度准则 rigidity criterion 垫圈 washer 垫片 spacer 直齿圆柱齿轮 straight toothed spur gear 斜齿圆柱齿轮 helical-spur gear 直齿锥齿轮 straight bevel gear 运动简图 kinematic sketch 齿轮齿条 pinion and rack 蜗杆蜗轮 worm and worm gear 虚约束 passive constraint 曲柄 crank 摇杆 racker 凸轮 cams
E---MARKETING (From:E--Marketing by Judy Strauss,Adel El--Ansary,Raymond Frost---3rd ed.1999 by Pearson Education pp .G4-G25.) As the growth of Googel. shows, some marketing principles never change.Markets always welcome an innovative new product, even in a crowded field of competitors ,as long as it provides customer value.Also,Google`s success shows that customers trust good brands and that well-crafted marketing mix strategies can be effective in helping newcomers enter crowded markets. Nevertheless, organizations are scrambling to determine how they can use information technology profitably and to understand what technology means for their business strategies. Marketers want to know which of their time-ested concepts will be enhanced by the Internet, databases,wireless mobile devices, and other technologies. The rapid growth of the Internet and subsequent bursting of the dot- bubble has marketers wondering,"What next?" This article attempts to answer these questions through careful and systematic examination of successful e-mar-keting strategies in light of proven traditional marketing practices. （Sales Promotion;E--Marketing；Internet；Strategic Planning ） 1.What is E--Marketing E--Marketing is the application of a broad range of information technologies for: Transforming marketing strategies to create more customer value through more effective segmentation ,and positioning strategies；More efficiently planning and executing the conception, distribution promotion,and pricing of goods,services,and ideas;andCreating exchanges that satisfy individual consumer and organizational customers` objectives. This definition sounds a lot like the definition of traditional marketing. Another way to view it is that e-marketing is the result of information technology applied to traditional marketing. E-marketing affects traditional marketing in two ways. First,it increases efficiency in traditional marketing strategies.The transformation results in new business models that add customer value and/or increase company profitability.
广东工业大学华立学院 本科毕业设计（论文） 外文参考文献译文及原文 系部经济学部 专业经济学 年级 2007级 班级名称 07经济学6班 学号 16020706001 学生姓名张瑜琴 指导教师陈锶 2011 年05月
目录 1挑战：小额贷款中的进入和商业银行的长期承诺 (1) 2什么商业银行带给小额贷款和什么把他们留在外 (2) 3 商业银行的四个模型进入小额贷款之内 (4) 3.1内在的单位 (4) 3.2财务子公司 (5) 3.3策略的同盟 (5) 3.4服务公司模型 (6) 4 合法的形式和操作的结构比较 (8) 5 服务的个案研究公司模型：厄瓜多尔和Haiti5 (9)
1 挑战：小额贷款中的进入和商业银行的长期承诺 商业银行已经是逐渐重要的运动员在拉丁美洲中的小额贷款服务的发展2到小额贷款市场是小额贷款的好消息客户因为银行能提供他们一完整类型的财务的服务，包括信用，储蓄和以费用为基础的服务。整体而言，它也对小额贷款重要，因为与他们广泛的身体、财务的和人类。如果商业银行变成重的运动员在小额贷款，他们能提供非常强烈的竞争到传统的小额贷款机构。资源，银行能廉宜地发射而且扩张小额贷款服务rela tively。如果商业广告银行在小额贷款中成为严重的运动员，他们能提出非常强烈的竞争给传统的小额贷款机构。然而，小额贷款社区里面有知觉哪一商业银行进入进入小额贷款将会是短命或浅的。举例来说，有知觉哪一商业银行首先可能不搬进小额贷款因为时候建立小额贷款操作到一个有利润的水平超过银行的标准投资时间地平线。或，在进入小额贷款，银行之后可能移动在－上面藉由增加贷款数量销售取利润最大值－或者更坏的事，退出如果他们是不满意与小额贷款的收益性的水平。这些知觉已经被特性加燃料商业银行的情形进入小额贷款和后来的出口之内。在最极端的，一些开业者已经甚至宣布，”降低尺度死！”而且抛弃了与主意合作的商业银行。 在最 signific 看得到的地方，蚂蚁利益商业银行可能带给小额贷款，国际的ACCION 发展发射而且扩张的和一些商业银行的关系小额贷款操作。在这些情形的大部分方面， ACCION 和它的合伙人正在使用方法，已知的当做服务公司模型，表演早答应当做一个能工作的方法克服真正的。 商业银行的障碍进入和穿越建立长命的小额贷款操作一个商业银行 这论文描述如何服务公司模型、住址商业银行中的主要议题进入进小额贷款，监定成功建立的因素动作井小额贷款服务公司，和礼物结果和小额贷款的课servic e 公司用最长的经验，在海地和审判官席 del 的 SOGEBANK│ SOGESOL 初期结果指出那这服务公司模型表现一重要的突破在促成商业银行进入和留在小额贷款。在厄瓜多尔的 Pichincha│ CREDIFE。初期结果指出服务公司模型在促成商业广告中表现一次重要的突破银行进入而且留在小额贷款。
The development of plastic mould China's industrial plastic moulds from the start to now, after more than half a century, there has been great development, mold levels have been greatly enhanced. Mould has been at large can produce 48-inch big-screen color TV Molded Case injection mold, 6.5 kg capacity washing machine full of plastic molds, as well as the overall car bumpers and dashboards, and other plastic mould precision plastic molds, the camera is capable of producing plastic mould , multi-cavity mold small modulus gear and molding mold. --Such as Tianjin and Yantai days Electrical Co., Ltd Polaris IK Co. manufactured multi-cavity mold VCD and DVD gear, the gear production of such size precision plastic parts, coaxial, beating requirements have reached a similar foreign the level of product, but also the application of the latest gear design software to correct contraction as a result of the molding profile error to the standard involute requirements. Production can only 0.08 mm thickness of a two-cavity mold and the air Cup difficulty of plastic doors and windows out of high modulus, and so on. Model cavity injection molding manufacturing accuracy of 0.02 to 0.05 mm, surface roughness Ra0.2 μ m, mold quality, and significantly increase life expectancy, non-hardening steel mould life up to 10~ 30 million, hardening steel form up to 50 ~ 10 million times, shorten the delivery time than before, but still higher than abroad,and the gap between a specific data table. Process, the multi-material plastic molding die, efficient multicolor injection mould, inserts exchange structure and core pulling Stripping the innovative design has also made great progress. Gas-assisted injection molding, the use of more mature technologies, such as Qingdao Hisense Co., Ltd., Tianjin factory communications and broadcasting companies, such as mold manufacturers succeeded in 29 ~ 34-inch TV thick-walled shell, as well as some parts on the use of gas-assisted mould technology Some manufacturers also use the C-MOLD gas-assisted software and achieved better results. Prescott, such as Shanghai, such as the new company will provide users with gas-assisted molding equipment and technology. Began promoting hot runner mold, and some plants use rate of more than 20 percent, the general heat-thermal hot runner, or device, a small number of units with the world's advanced level of rigorous hot runner-needle device, a small number of units with World advanced level of rigorous needle-hot runner mould. However, the use of hot runner overall rate of less than 10%, with overseas compared to 50 ~ 80%, the gap larger. In the manufacturing technology, CAD / CAM / CAE technology on the level of application of a new level to the enterprise for the production of household appliances representatives have introduced a considerable number of CAD / CAM systems, such as the United States EDS UG Ⅱ,
外文翻译 英文原文 Belt Conveying Systems Development of driving system Among the methods of material conveying employed，belt conveyors play a very important part in the reliable carrying of material over long distances at competitive cost．Conveyor systems have become larger and more complex and drive systems have also been going through a process of evolution and will continue to do so．Nowadays，bigger belts require more power and have brought the need for larger individual drives as well as multiple drives such as 3 drives of 750 kW for one belt(this is the case for the conveyor drives in Chengzhuang Mine)．The ability to control drive acceleration torque is critical to belt conveyors’ performance．An efficient drive system should be able to provide smooth，soft starts while maintaining belt tensions within the specified safe limits．For load sharing on multiple drives．torque and speed control are also important consideratio ns in the drive system’s design. Due to the advances in conveyor drive control technology，at present many more reliable．Cost-effective and performance-driven conveyor drive systems cov ering a wide range of power are available for customers’ choices[1]. 1 Analysis on conveyor drive technologies 1．1 Direct drives Full-voltage starters．With a full-voltage starter design，the conveyor head shaft is direct-coupled to the motor through the gear drive．Direct full-voltage starters are adequate for relatively low-power, simple-profile conveyors．With direct fu11-voltage starters．no control is provided for various conveyor loads and．depending on the ratio between fu11- and no-1oad power requirements，empty starting times can be three or four times faster than full load．The maintenance-free starting system is simple，low-cost and very reliable．However, they cannot control starting torque and maximum stall torque；therefore．they are
互联网网络营销外文文献翻译 (含：英文原文及中文译文) 文献出处：Peter Kenzelmann. Technical Consultancy in Internationalization[J]. International Marketing Review, 2006, 4(3):20-29. 英文原文 The technical basis of network marketing Peter Kenzelmann Network marketing is based on the technology infrastructure of computer network technology, as represented by information technology. Computer networks of modern communications technology and computer technology to the product of combining it in different geographic regions and specialized computer equipment for external interconnection lines of communication into a large, powerful networks, thus enabling a large number of computers can easily transmit information to each other, share hardware, software, data and other resources. And network marketing is closely related to the computer network there are three types: the Internet, Extranet and Intranet. The theoretical basis for the network marketing Theoretical foundation of network marketing is direct marketing network theory, network theory of relationship marketing, marketing theory and network software to integrate marketing theory. (A) Direct Response Network Marketing Theory
关于毕业设计说明书（论文）英文文献及中文翻译撰写格式 为提高我校毕业生毕业设计说明书（毕业论文）的撰写质量，做到毕业设计说明书（毕业论文）在内容和格式上的统一和规范，特规定如下: 一、装订顺序 论文（设计说明书）英文文献及中文翻译内容一般应由3个部分组成，严格按以下顺序装订。 1、封面 2、中文翻译 3、英文文献（原文） 二、书写格式要求 1、毕业设计（论文）英文文献及中文翻译分毕业设计说明书英文文献及中文翻译和毕业论文英文文献及中文翻译两种，所有出现相关字样之处请根据具体情况选择“毕业设计说明书” 或“毕业论文”字样。 2、毕业设计说明书（毕业论文）英文文献及中文翻译中的中文翻译用Word 软件编辑，英文文献用原文，一律打印在A4幅面白纸上，单面打印。 3、毕业设计说明书（毕业论文）英文文献及中文翻译的上边距:30mm；下边距:25mm；左边距:3Omm；右边距:2Omm；行间距1.5倍行距。 4、中文翻译页眉的文字为“中北大学2019届毕业设计说明书” 或“中北大学××××届毕业论文”，用小四号黑体字，页眉线的上边距为25mm；页脚的下边距为18mm。 5、中文翻译正文用小四号宋体，每章的大标题用小三号黑体，加粗，留出上下间距为：段前0.5行，段后0.5行；二级标题用小四号黑体，加粗；其余小标题用小四号黑体，不加粗。 6、文中的图、表、附注、公式一律采用阿拉伯数字分章编号。如图1.2，表2.3，附注3.2或式4.3。 7、图表应认真设计和绘制,不得徒手勾画。表格与插图中的文字一律用5号宋体。
每一插图和表格应有明确简短的图表名，图名置于图之下，表名置于表之上，图表号与图表名之间空一格。插图和表格应安排在正文中第一次提及该图表的文字的下方。当插图或表格不能安排在该页时，应安排在该页的下一页。 图表居中放置，表尽量采用三线表。每个表应尽量放在一页内，如有困难，要加“续表X.X”字样，并有标题栏。 图、表中若有附注时，附注各项的序号一律用阿拉伯数字加圆括号顺序排，如:注①。附注写在图、表的下方。 文中公式的编号用圆括号括起写在右边行末顶格，其间不加虚线。 8、文中所用的物理量和单位及符号一律采用国家标准，可参见国家标准《量和单位》(GB3100~3102-93)。 9、文中章节编号可参照《中华人民共和国国家标准文献著录总则》。
Abstract: A supporting body of diatomite-based porous ceramics was prepared by a solid-phase sintering process and low-temperature calcination process. A nano-TiO2 compound membrane was loaded on the supporting body by the hydrolysis precipitation method and using TiCl4 as the forerunner body, and the TiO2/diatomite-based porous ceramic composite structure was characterized by X-ray diffraction and scanning electron microscopy and so on. The photocatalytic activities of TiO2 films were investigated by the degradation of formaldehyde. The results indicate that the TiO2 films in TiO2/diatomite-based porous ceramic composite calcined at 550 ℃are anatase, and the average grain size of TiO2 is 10.9 nm. The elimination rate of the composites for formaldehyde reaches 96.8% in 6 h under an ultraviolet lamp irradiation of 8 W, and the concentration of formaldehyde drops to 0.015 mg/m3 from 0.463 mg/m3. Key words: diatomite-based porous ceramics; nano-titania compound membrane; water solution precipitation method; formaldehyde; photocatalytic activity 摘要：采用固相烧结法和低温煅烧工艺，制备了硅藻土基多孔陶瓷支承体。以四氯化钛为前驱体，采用水解沉淀法在支承体上负载纳米TiO2复合膜。用X射线衍射仪和扫描电子显微镜等对TiO2复合膜/多孔陶瓷支承体的复合结构进行了表征；并以甲醛为降解对象，考察了TiO2复合膜的光催化性能。结果表明：纳米TiO2/硅藻土基多孔陶瓷复合膜在550℃煅烧后TiO2为锐钛矿型，平均晶粒粒径为10.9 nm。在紫外光照射240min后，甲醛气体初始浓度由0.463 mg/m3 降至0.015 mg /m3，复合材料对甲醛的去除率达到96.8%。 关键词：硅藻土基多孔陶瓷；纳米二氧化钛复合膜; 水解沉淀法；甲醛；光催化性能Abstrac:t Photocatalytic ceramic foam filter, the composite of high photo active TiO2 nano mate rials and three dimensional porous ceramic foam materials, has been widely applied in the field of air /water purification, owing to its characteristics of high photoactivity, large surface area, large flowing flux and ceramic heat/ chemical resistance, recycling probability. Applications have been in the fields of industrial exhaust deodorization, agriculture pesticide degradation using sunlight, sterilization of laboratories and hospitals, high-speed train air purification, and so on. The application research progress, problem and future prospect of photo catalytic ceramic foam filter are summarized. Key words: photo catalyst; ceramic foam filter; application; air /water purification 摘要: 高活性的光催化二氧化钛纳米材料与高气孔率的三维多孔泡沫陶瓷材料复合, 得到的光催化泡沫陶瓷过滤器, 具备高活性、大表面积、大通量、以及陶瓷的耐高温、耐化学腐蚀、循环适用性, 在大气/水净化领域率先得到了广泛应用。在工业领域的废气脱臭处理、在农业领域的农药废水太阳光降解、在医疗卫生领域的实验室医院空气杀菌处理、在交通领域的高速列车空气净化等, 已经展开应用。综述了国内外光催化泡沫陶瓷过滤器的应用研究现状、问题及其发展趋势。 关键词: 光催化; 泡沫陶瓷过滤器; 应用研究; 大气/水净化
机械专业相关词汇中英文翻译大全 单价unit price 工日合计Man-day total/work-day total 人工费cost of labor 材料费materials expenses 机械的mechanical 检查接线connection test 发电机generator 调相机phase regulator 周波cycle 减负荷装置 load-shedding equipment 断路器柜circuit breaker cabinet 单母线single busbar 互感器transformer 每相电流Current by Phase 封闭式插接close type socket joint 发电机控制面板generator control panel 分级卸载sorted unloading 同步控制synchronization control 调速器 speed governor 信号屏signal screen 继电器relay 高压柜high pressure cabinet 油浸电力变压器oil-immersed power transformer 空气断路器air circuit breaker 控制屏control panel 直流馈电屏direct current feed control panel 电容器electric condenser 计量盘metering panel 成套配电箱whole set of distribution box 落地式floor model 控制开关Control switches 铜芯电力电缆Copper core power cable 控制电缆actuating cable 热缩式电力电缆终端头pyrocondensation power cable terminal 钢结构支架配管steel structure bracket tubing 万用槽钢versatile U-steel 电缆托架 cable bracket 钢制托盘式桥架steel Tray-type cable support system waterproof socket 防水插座 防爆插座Explosion-proof socket 接地绞线earthing twisted pair 接地母线 earthing bus
文献出处：Guzzo T, D’Andrea A, Ferri F, et al. Evolution of Marketing Strategies: From Internet Marketing to M-Marketing[C]//On the Move to Meaningful Internet Systems: OTM 2012 Workshops. Springer Berlin Heidelberg, 2012: 627-636. 原文 Evolution of Marketing Strategies:From Internet Marketing to M-Marketing Tiziana Guzzo, Alessia D’Andrea, Fernando Ferri, and Patrizia Grifoni 1 Introduction Marketing is “the process which creates, communicates, delivers the value to the consumers, and maintains the relationship with consumers. It generates the strategy that underlies sales techniques, business communication, and business developments. It is “an integrated process through which companies build strong consumers relationships and create value for their consumers and for themselves” Marketing strategies have a long history and mainly interested economists and sociologists. The wide use of Internet, pervasiveness of social networks and the evolution of mobile devise are implying a wider involvement of interdisciplinary competences enlarging the interest toward ICT competences. This paper is to describe the evolution of marketing strategies from the advent of the Web (Internet Marketing) - through the advent of Social Networks (Marketing 2.0) - to the evolution of Mobile Social Networks (M-marketing). In particular, the paper analyses the use that Italian people make of mobile devices and the user perception and acceptance of M-marketing.