Context-Aware Access Control for Collaborative Working Environments Based on Semantic
Social Networks
Peyman Nasirifard
Digital Enterprise Research Institute
National University of Ireland,Galway
IDA Business Park,Lower Dangan,Galway,Ireland
peyman.nasirifard@https://www.doczj.com/doc/c813127573.html,
Abstract.Most current shared workspaces within Collaborative Work-
ing Environments(CWE)provide role-based coarse-grained access con-
trol mechanisms for eProfessionals which do not satisfy their require-
ments in most cases.When e-Professionals collaborate in CWE,they
leave some?ngerprints,which contain highly valuable information.These
?ngerprints can be exported and used to extract the hidden social net-
works based on the objects that eProfessionals collaborate upon.Social
networks have great potentials to be used within di?erent domains like
designing access control policies.Context information of eProfessionals is
also a great source to be used within access control mechanisms.In this
paper,I present an approach for access control mechanism within CWE
based on context,trust,and social networks.These are key elements for
expressing access control policies.I intend to enrich the framework with
Semantic Web technologies and ontologies.
Key words:Social Network,Access Control,Collaborative Working
Environment,Context-Aware Access Control,Social Network Analysis,
Trust in Social Network,Semantic Social Network,Social Network Min-
ing
1Introduction
E-professional or”eProfessional”is a term used in Europe to describe a pro-fessional whose work relies on concepts of Telework or Telecommuting:working at a distance using information and communications technology[59].Internet has provided an infrastructure for eProfessionals to collaborate and work to-wards the same goal in a corporate environment which is so-called Collaborative Working Environment(CWE).The CWEs enable eProfessionals to share di?er-ent resources,e.g.documents or events among other eProfessionals in a platform which is so-called shared workspaces.One of the main disadvantages of current platforms is the lack of a?ne-grained access control mechanism.Most current platforms provide role-based coarse-grained access control mechanisms that do not meet the eProfessionals’requirements,e.g.temporal requirements.Social
networks,which can be represented as graphs,have great potentials to be used in di?erent domains like designing access control policies based on relationships among actors.When eProfessionals collaborate in CWE,they leave some?nger-prints that are highly valuable and can be used for extracting social networks. Most current environments are able to export the activities(events)that are done as feeds or log?les.The social networks among eProfessionals,extracted par-tially from?ngerprints,and enriched with trust and context,are good candidates to be used within access control policies.The whole framework can be enriched with Semantic Web technologies to make it more machine-understandable.
In this paper,which is actually my Ph.D.proposal,?rst I focus on back-ground information:I present essential de?nitions and concepts regarding social networks,collaborative working environments,di?erent access control mecha-nisms,context-aware access controls etc.Then I consider the problem that cur-rently exists in access control mechanism within most shared workspaces for eProfessionals and?nally I have a rough overview of my approach towards solv-ing the problem.During this paper,I try to answer following questions regarding my Ph.D.proposal:
–What is the problem that I am going to solve?
–What do I want to do?
–Why my approach is important?
–How does my approach di?er from prior works?
–What do I have so far?
–How am I going to do the work?
2Relevant Background
2.1Social Networks and Social Acquaintances
Social networks[36],as a sort of Scale-free networks[21],can be represented as graphs using the famous notions of nodes and edges between them.Obviously,the concept of social network is not something new and its origin is not also computer science.Social networks are good means to model the connections between people based on di?erent relationships that the actors may acquire during a period of time.The small world phenomenon[37],based on Milgram’s idea of six degrees of separation[22],presents the concept that everyone in the world is connected to all people in the world by a short chain of social relationships.Some practical e?orts like The small world project1at university of Columbia have proved this theoretical phenomenon.It is obviously a good indicator for the hidden power of social networks.
Roughly speaking,social networks fall into two main groups:object-centric social networks and non-object-centric which I call them user-centric social net-works.The term object-centric social network has been coined by Jyri Engestr¨o m in his blog post2and indicates those social networks that are built on top of 1https://www.doczj.com/doc/c813127573.html,/
2https://www.doczj.com/doc/c813127573.html,/blog/2005/04/why_some_social.html
objects,e.g.the actors make a social network conceptually around a photo or a movie clip.Engestr¨o m argues that the main reason that some Web-based social network sites fail after a while is the fact that they are not object-centric and the users lose their motivations to be connected.
A social network can be analyzed based on di?erent metrics,like Central-ity Closeness and Betweenness[40],[41].These metrics can identify di?erent characteristics and potentials of social networks.
One of the research areas in social networks is addressing the di?erent rela-tionships that the actors may acquire in a period of time.Ontological consider-ation on human relationships has been considered by some researchers:Matsuo et al.[51]provide some consideration towards this direction and present several distinctions across relationships between humans.Davis et al.[38]introduce RE-LATIONSHIP which is a set of vocabularies for describing relationships between people.Carminati et al.[39]propose REL-X vocabulary,which is another e?ort towards this direction.Gan et al.[52]provide several vocabularies as FOAF extensions to cover the often changing variables in FOAF.This work can be considered as providing context information for FOAF pro?les.
2.2Collaborative Working Environment
Collaborative Working Environments(CWE)are platforms and infrastructures that support working between people(eProfessionals)by means of di?erent tech-nologies and tools.The CWE was in existence before the birth of computers and Internet.The concept of e-Collaboration,which?rst appeared in1980s,have been studied by many researchers.Kock[42]de?nes e-Collaboration and has an overview of six key conceptual elements of e-Collaboration.
2.3Semantic Web and Semantic Social Network
Semantic Web[1],as an extension to current Web,is actually a set of technolo-gies and standards which tries to help machines to understand concepts and extract new information based on existing well-de?ned https://www.doczj.com/doc/c813127573.html,ing Se-mantic Web,software engineers are able to build interoperable systems that can bene?t from machines to combine data and reason on existing data and infer new information.Ontologies are main building blocks and fundamental elements of Semantic Web and try to de?ne a speci?c domain in a systematic way.Ontolo-gies can be represented using di?erent standards and languages like RDFS[3] and OWL[2].Both are based on Resource Description Framework(RDF)[63] which is a language for representing information about resources.OWL comes in three main?avors:OWL Lite,OWL DL and OWL Full which have been sorted according to expressivity and complexity levels.
Combining Semantic Web and social networks is an interesting area for many researchers.One of the main initiatives towards building a semantic social net-work is FOAF3(Friend of a Friend)project[44].In brief,FOAF provides some 3https://www.doczj.com/doc/c813127573.html,/
basic vocabularies that are needed to describe people,their interests,their friends etc.E?orts like XFN4(XHTML Friends Network)tries to embed social net-works and human relationships using hyperlinks like HTML.Neumann et al.[9] compare di?erent online social networks based on di?erent criteria and try to conclude with the importance of combining social networks and Semantic Web portals for a better collaboration in online communities.Downes[10]tries to address the need of social network metadata within semantic metadata.Jung et al.[14]propose a three-layer architecture(social layer,ontology layer,and concept layer)for semantic social networks which all these three layers are con-nected together and can in?uence each other.In[62]Mika extends the model of ontologies with social dimension and shows how community-based semantics can appear from this new model through a process of graph transformation.
Most researchers[47],[46],[50]in this area use FOAF as a basis model and extend it partially and gather a benchmarking corpus from extracted information which is available mostly on the Internet.Mika[13],[48]did some work on mining social networks based on a hybrid approach from FOAF pro?les and also information extracted from Google and ranked through Google Mindshare [45]for building and analyzing social networks among Semantic Web researchers (Flink5project).Due to availability of semantic search engines and open data like[49],this approach sounds to be more interesting among others.Goecks et al.
[54]provide an infrastructure that uses social networks for information sharing. They extract social networks from users’email messages.Mori et al.[53]have the similar approach,but they use di?erent sources like Web pages,emails,sensors and enable users to control their resources.This is performed automatically,but end users can also access and obviously change their social networks.
2.4Trust in Social Networks and Semantic Web
One of the most famous works in de?ning a computational model of trust is [11].In this work,Marsh took into the account the concept of trust in di?erent domains and based on this consideration,he developed a trust model for a dis-tributed environment.In[12],Golbeck has studied trust in social networks and proposed several algorithms for computing trust in social networks and evaluated this model using some applications like TrustMail.
Trust and Semantic Web have been studied in di?erent domains,mainly for recommendation systems.In[4],Bedi et al.suggest a semantic recommendation system based on trust and they apply their model to a tourism recommender system which generates recommendations for a selection of destinations.
2.5Context in Social Networks and CWE
It is di?cult to give one valid global de?nition to context.The main reason is that there is no absolute context and context gets its meaning in relative to 4https://www.doczj.com/doc/c813127573.html,/xfn/
5https://www.doczj.com/doc/c813127573.html,/
something[64].The lack of su?cient literature on studying the roles of contexts and contextualizations in social networks is apparent.There exist some works like[5],[6],[7]which try to address some aspects of contextualizations in social networks,but they seem to be preliminary https://www.doczj.com/doc/c813127573.html,ing shared context in CWE to improve and support collaborative tasks has been also studied in some works like[8].
2.6Access Control
Access control is the ability to permit or deny the use of something by some-one[43].There exist plenty of approaches and mechanisms towards controlling the access:access control lists,role-based access control,attribute-based access control,ontology-based access control etc.There exist a lot of formal languages that aim to express access control policies with di?erent perspectives and gran-ularities,like XACML[56],which is an extensible access control language and is currently used in many frameworks,P3P[57],which is too coarse-grained to be used in di?erent domains,EPAL[55],which is more machine-readable,Rei [58],which is an ontlogy-based policy language,and KAoS[60],which is an-other ontology-based policy framework which is well-suited for Semantic Web services etc.Many researchers try to combine di?erent access control mecha-nisms to build a more powerful mechanism and decrease the disadvantages of each mechanism.Kern et al.[23]provide an architecture for role-based access control to use di?erent rules to extract dynamic roles.Alotaiby et al.[29]present a team-based access control which is built upon role-based access control.Peri-orellis et al.[30]introduce another extension to role-based access control which is called task-based access control.They discuss task-based access control as a mechanism for dynamic virtual organisation scenarios.Kim et al.[34]propose a collaborative role-based access control(C-RBAC)model for distributed systems which is?ne-grained and try to address the con?icts from cross-domain role-to-role translation.Toninelli et al.[61]present an approach towards combining rule-based and ontology-based policies in pervasive environments.
There exist some e?orts towards enriching access control mechanisms by means of Semantic Web technologies.Li et al.[25]propose a rule based access control which is based on OWL and SWRL[26].They propose an OWL ontol-ogy to describe the terms and access policy rules will be expressed in SWRL. Priebe et al.[31]discuss that attribute-based access control(ABAC)is a bit complex and error-prone and they propose a solution by pushing Semantic Web technologies and ontologies into ABAC.
The study of access control mechanisms in CWE is not new and was in existence from the birth of e-Collaboration.Shen et al.[33]studied access control mechanisms in a simple collaborative environment,i.e.a simple collaborative text editing environment.Zhao[20]has an overview on three main access control mechanisms and provides a comparison between these three main mechanisms in collaborative environments.Tolone et al.[19]provide a comprehensive study on access control mechanisms in collaborative systems and they compare di?erent mechanisms based to di?erent criteria,https://www.doczj.com/doc/c813127573.html,plexity,understandability,ease
of use,etc.There exist also di?erent studies on access control requirements in collaborative systems.Jaeger et al.[28]present basic requirements for role-based access control within collaborative systems.Guti′e rrez Vela et al.[32]try to model an organization in a formal way that considers the necessary elements to represent the authorization and access control policies.Demchenko et al.[35] propose an access control model and mechanism for grid-based collaborative applications.
There exist some studies on access control in social networks.Most of the literature focus on relationships that the people may acquire in a social network. In[18],Kruk et al.suggest a role-based policy-based access control for social net-works,where the access rights will be determined based on social links and trust levels between people.In[15],Carminati et al.present the same approach and in[16],they extend their model by adding the concept of private relationships in access control,as they noticed that all relationships within social networks should not be public,due to security and privacy reasons.
Using context information in access control mechanisms has been studied by di?erent researchers.Toninelli et al.[17]suggest a semantic context-aware access control framework for secure collaboration in pervasive computing en-vironments.They propose a simple OWL-based context model and based on this model,they propose a context-aware policy model and they support their model by a meeting scenario case study,where the attending people can access the meeting resources only during the meeting.They express policy statements using description logic.Georgiadis et al.[24]provide a model for combining con-textual information with team-based access control and they provide a scenario in health care domain,where the model is used.Zhang et al.[27]propose a model for dynamic context-aware role-based access control for pervasive applications. They extend role-based access control and dynamically align role and permission assignments based on context information.
3Problem
In a collaborative working environment,where the eProfessionals collaborate, there should exist some kind of access control mechanism,as eProfessionals share di?erent resources(e.g.pro?les information,documents,events,etc.)and shared resources should be protected against unauthorized accesses within shared workspaces.Most current shared workspaces provide a coarse-grained role-based access control mechanism which is not?exible and in most cases seems to be e?ectless,especially when the number of eProfessionals increases.
I present a scenario to explain this problem in a more detailed manner:Bob is the name of the main actor.He is currently working on an European project in a collaborative distributed infrastructure with other team members from di?erent organizations.Partners are geographically distributed in di?erent countries with di?erent time zones.This project has di?erent Work Packages(WP)and Bob is the leader of WP two.The project has a Web site for public visitors.This Web site includes project news,newsletters,public events,some public deliverables
and information about the scope and the mission of the project.The project has also a private collaborative working environment(shared workspace).The pri-vate side includes a wiki,a forum,a calendar to document events,some folders for uploading documents to be accessed by team members,a bunch of docu-ments,presentations,photos from meetings,contracts,time sheets etc.Partners have sometimes conference calls to discuss online or via telephone.They meet regularly each two/three months to setup things and discuss the progress of the project.In this private workspace,Bob has uploaded some documents,photos, and presentations.The issue is that not all project members should access Bob’s resources.In our case,Bob wants to set the following access control rules based on the roles de?ned by the project.
–Bob wants to give access of work-in-progress deliverables to all WP leaders plus the project coordinator and if some of them are not available(e.g.on vacation),to their proxies.
–Bob wants to give access of a con?dential contract only once and only to a speci?c person.
–Bob wants to give access of a particular presentation only during the meeting (temporal restrictions)and only to speci?c meeting participants.
–Bob wants to give access of a particular background document only to mem-bers that are currently working on a particular deliverable.
–Bob wants to share a photo only to his close friends(or his colleagues from his company)within this project.
–Bob wants to give access of his presentation,only after?nishing it and only to particular members.
–Bob does not want to give access of a document to friends that were not present in a particular meeting and their trust levels are less than a threshold.–Special rule:Bob wants to share a technical report with responsible persons from other projects that are related to his project(same domain)
–and more rules...
The above items are just some simple requirements for setting access control policies.In general,with current role-based access control mechanisms within most CWEs(shared workspaces),it seems to be very di?cult or even impossi-ble to apply above rules.The lack of a?ne-grained access control mechanism for shared workspaces within collaborative working environments is the main problem that I want to address in my thesis.The term?ne-grained refers to a?exible,parametric,context-aware,open and extensible access control mech-anism.Towards this direction,in next section,I explain how social networks within most CWEs and context information can help to express and apply more ?exible access control rules.
4Approach
Generally,to realize above scenario,I plan to build a context-aware access control for shared workspaces within collaborative working environments based on social
networks.Social networks are key players,as their model is very similar to what we utilize in our o?ine lives to give access to the people that we communicate with.To achieve this goal,the?rst problem that should be addressed is modeling social networks in di?erent layers:based on social acquaintances and also roles within a collaborative working environment and organization.Besides this user-de?ned(manual)social network,there exist also some(semi-)automated ways to extract the hidden social networks in shared workspaces.This hidden social network,which connects people by means of dynamic relationships,is based on the objects that connect people(i.e.object-centric social networks),and can be extracted using di?erent mechanisms,like processing the log?les and feeds.As an example,if user A reads a document that has been written by user B,the hidden relationship between two users is“ReadWrite”from user A to user B and “WriteRead”from user B to user A.These hidden relationships enable building parametric social networks and help to recommend the appropriate candidates for sharing resources.
One key candidate for representing social networks is an extended version of FOAF to meet the new requirements.I believe that this area(mining social network)is a very wide area and di?erent sources can be considered towards this direction,but the main focus of my thesis is not on this section.In this step,I will have an overview of possibilities for de?ning/mining social networks from shared workspaces and provide a simple proof of concept.This approach should bene?t from ontologies for machine-understandability,like an ontology for di?erent sources that help to build social networks,an ontology for properties of a graph,etc.
The next problem is de?ning a context model that is extensible and suitable enough to model context information of eProfessionals with regards to CWE. This model should contain all required context information that is helpful for expressing access control policies.Obviously,this model and the model of social networks should refer to each other.
The analysis of social networks based on di?erent criteria that make sense for access control and then calculating trust among eProfessionals based on their dynamic relationships are the next sub-problems that should be solved.Di?er-ent characteristics of social networks should be considered to check whether they make sense to be embedded in access control scenarios or not.These character-istics vary from those related to graph-theory(e.g.in-degree,out-degree)to new de?ned ones.
One of the main goals is to allow end users to express access control poli-cies based on context information,trust and social network analysis.Probably ontology-based description which is actually a logic-based approach is a key candidate towards this direction.
The?nal step is related to the construction of the main engine that gets the enriched social networks and access control rules as inputs and decides the accessibility of resources for di?erent users.Figure1demonstrates the overall view and the whole process that I plan to work on it.
To summarize,below I present a list of items that are related to my research:
Fig.1.General Overview of Solution
–Modeling the collaborative working environment as social networks
–Mining social networks from shared workspaces within CWEs based on the objects that eProfessionals collaborate upon and the di?erent roles that they acquire
–Modeling the required CWE context information
–Proposing trust criteria for di?erent characteristics and dynamic relation-
ships in social networks within CWEs
–Expressing access control rules with consideration of the model of social network,trust and context criteria
–Designing an engine that gets access control rules and enriched social net-works as inputs and decides the accessibility of resources for di?erent users –Supporting all layers with semantic technologies to make relevant informa-tion more machine-understandable
5Conclusion
Most current shared workspaces within CWEs provide a role-based access control mechanism which is in most cases in?exible and e?ectless.Social networks and contexts are two main candidates to enrich the legacy access control mechanism for a more?exible approach.In this paper,I discussed the lack of a?ne-grained context-aware access control for CWEs using a scenario and based on require-ments,I proposed a context-aware access control mechanism based on social networks within CWEs.In my approach,context information of eProfessionals, trust,and explicit and implicit social networks within CWEs are key concepts. The implicit social network can be extracted by monitoring the behaviors of eProfessionals,when they collaborate in CWEs.I enrich the framework with Se-mantic Web technologies and ontologies.This approach enables users to express and apply?exible access control rules based on their relationships with other eProfessionals,trust and their context information.
Acknowledgments.This work is supported by inContext(Interaction and Context Based Technologies for Collaborative Teams)project:FP6-IST-2006-034718and Ecospace(Integrated Project on eProfessional Collaboration Space) project:FP6-IST-5-35208
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赛区评阅编号（由赛区组委会填写）： 2016年高教社杯全国大学生数学建模竞赛 承诺书 我们仔细阅读了《全国大学生数学建模竞赛章程》和《全国大学生数学建模竞赛参赛规则》（以下简称为“竞赛章程和参赛规则”，可从全国大学生数学建模竞赛网站下载）。 料 我们的报名参赛队号（12位数字全国统一编号）： 参赛学校（完整的学校全称，不含院系名）： 参赛队员 (打印并签名) ：1. 2.
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系泊系统的设计和探究 摘要 本文利用牛顿力学定律，力矩平衡原理、非线性规划、循环遍历法等方法对系泊系统进行了设计与探究。通过对系泊系统各组件和浮标运用牛顿经典力学体系进行分析，得到了各个情况下的钢桶倾斜角度、锚链状态、浮标吃水深度和游动区域。 ?， 。当风 对于第二问，求解当海面风速为36m/s时，浮标的吃水深度和游动区域、钢桶以及钢管的倾斜角度和锚链形态。利用第一问中的力学方程和程序，求得钢桶的倾角为19.5951?和四节钢管的倾斜角度依次为19.756?、19.755?、19.916?、20.076?。浮标的游动区域为以锚在海面上的投影为圆心，半径为18.8828m的圆。由于部分数据与问题二中钢桶的倾斜角度不超过5?，锚链在锚点与海床的夹角不超过16?的要求不符，所以通过调节重物球的质量使钢桶的倾斜角度和锚链在锚点与海床的夹角处在要求的范围之内。借助MATLAB程序中的循环遍历法，可以求得重物球的质量3770kg。
编写Windows https://www.doczj.com/doc/c813127573.html,的usb驱动程序教程 Windows https://www.doczj.com/doc/c813127573.html, 是微软推出的功能强大的嵌入式操作系统，国内采用此操作系统的厂商已经很多了，本文就以windows https://www.doczj.com/doc/c813127573.html,为例，简单介绍一下如何开发windows https://www.doczj.com/doc/c813127573.html, 下的USB驱动程序。 Windows https://www.doczj.com/doc/c813127573.html, 的USB系统软件分为两层： USB Client设备驱动程序和底层的Windows CE实现的函数层。USB设备驱动程序主要负责利用系统提供的底层接口配置设备，和设备进行通讯。底层的函数提本身又由两部分组成，通用串行总线驱动程序（USBD）模块和较低的主控制器驱动程序（HCD）模块。HCD负责最最底层的处理，USBD模块实现较高的USBD函数接口。USB设备驱动主要利用 USBD接口函数和他们的外围设备打交道。 USB设备驱动程序主要和USBD打交道，所以我们必须详细的了解USBD提供的函数。 主要的传输函数有： abourttransfer issuecontroltransfer closetransfer issuein te rruptransfer getisochresult issueisochtransfer gettransferstatus istransfercomplete issuebulktransfer issuevendortransfer 主要的用于打开和关闭usbd和usb设备之间的通信通道的函数有： abortpipetransfers closepipe isdefaultpipehalted ispipehalted openpipe resetdefaultpipe resetpipe 相应的打包函数接口有： getframelength getframenumber releaseframelengthcontrol setframelength takeframelengthcontrol 取得设置设备配置函数： clearfeature setdescriptor getdescriptor setfeature
系泊系统的设计 摘要 对于问题一，建立模型一，已知题目给出的锚链长度与其单位长度的质量，得到悬链共210环。对各节锚链，钢桶，四节钢管受力分析得出静力平衡方程，使用分段外推法，可以得到静力平衡下的迭代方程。其中锚对锚链的拉力大小方向为输入变量，迭代的输出变量为浮标的位置和对钢管的拉力，在给定的风速下，输入和输出满足关系2)2(25.1cos 水v h T -=α，αθcos cos 11T T =，通过多层搜索算法得出最符合的输入输出值，即可得到给定风速下浮标的吃水深度，浮标拉力、锚链与海床夹角。利用MATLAB 软件编程求解模型得到：风力12m/s 时，钢桶与竖直方向上的角度1.9863度，从下往上四节钢管与竖直方向夹角为1.9652度、1.9592度、1.9532度、1.9472度，浮标吃水0.7173m ，以锚为圆心浮标的游动区域16.5125m ，锚链末端切线与海床的夹角3.8268度。风力24m/s 时，锚链形状，钢桶与竖直方向上的夹角3.9835度，从下往上四节钢管与竖直方向夹角为3.9420度、3.9301度、3.9183度、3.9066度，浮标吃水0.7244m ，以锚为圆心浮标的游动区域18.3175m 。锚链末端切线与海床夹角15.9175度。 对于问题二的第一小问，使用模型一求解，当风速36m/s 时，锚链末端切线与海床夹角26.3339度，浮标吃水0.7482m ，浮标游动区域为以锚为圆心半径为18.9578m 的圆形区域，从下往上四节钢管与竖直方向倾斜角度为8.4463度、8.4225度、8.3989度、8.3753度，钢桶与竖直方向倾斜角度为8.5294度。为满足问题二的要求，在模型一的基础上把重物球质量作为变量，建立模型二，将钢桶倾斜角小于5度和锚链前端夹角小于16度当做两个约束条件，通过MATLAB 编程求解得到满足约束条件要求的重物球质量取值范围为3700kg 到5320kg 。 对于问题三，首先取不同水深、水速、风速三种情况，建立模型三，即在模型一的基础上增加水流对系统产生的影响。在三种情况下，找到合适的锚链型号、锚链长度，重物球质量，对吃水深度、游动区域、钢桶的倾斜角三个目标进行优化达到最小。通过MATLAB 编程实现该模型三得到结果：选用Ⅲ型锚链，锚链长度为27.24m ，重物球质量为2580kg 。 关键词：平面静力系分析 多层搜索算法 遗传算法 逐步外推法 多目标优化
USB驱动程序编写 linux下usb驱动编写（内核2.4）——2.6与此接口有区别2006-09-15 14:57我们知道了在Linux 下如何去使用一些最常见的USB设备。但对于做系统设计的程序员来说，这是远远不够的，我们还需要具有驱动程序的阅读、修改和开发能力。在此下篇中，就是要通过简单的USB驱动的例子，随您一起进入USB驱动开发的世界。 USB骨架程序（usb-skeleton），是USB驱动程序的基础，通过对它源码的学习和理解，可以使我们迅速地了解USB驱动架构，迅速地开发我们自己的USB硬件的驱动。 USB驱动开发 在掌握了USB设备的配置后，对于程序员，我们就可以尝试进行一些简单的USB驱动的修改和开发了。这一段落，我们会讲解一个最基础USB框架的基础上，做两个小的USB驱动的例子。 USB骨架 在Linux kernel源码目录中driver/usb/usb-skeleton.c为我们提供了一个最基础的USB驱动程序。我们称为USB骨架。通过它我们仅需要修改极少的部分，就可以完成一个USB设备的驱动。我们的USB驱动开发也是从她开始的。 那些linux下不支持的USB设备几乎都是生产厂商特定的产品。如果生产厂商在他们的产品中使用自己定义的协议，他们就需要为此设备创建特定的驱动程序。当然我们知道，有些生产厂商公开他们的USB协议，并帮助Linux驱动程序的开发，然而有些生产厂商却根本不公开他们的USB协议。因为每一个不同的协议都会产生一个新的驱动程序，所以就有了这个通用的USB驱动骨架程序，它是以pci 骨架为模板的。 如果你准备写一个linux驱动程序，首先要熟悉USB协议规范。USB主页上有它的帮助。一些比较典型的驱动可以在上面发现，同时还介绍了USB urbs的概念，而这个是usb驱动程序中最基本的。 Linux USB 驱动程序需要做的第一件事情就是在Linux USB 子系统里注册，并提供一些相关信息，例如这个驱动程序支持那种设备，当被支持的设备从系统插入或拔出时，会有哪些动作。所有这些信息都传送到USB 子系统中，在usb骨架驱动程序中是这样来表示的： static struct usb_driver skel_driver = { name: skeleton, probe: skel_probe, disconnect: skel_disconnect, fops: &skel_fops, minor: USB_SKEL_MINOR_BASE, id_table: skel_table,
家装用尺寸一览表 Revised by Hanlin on 10 January 2021
家装用尺寸一览表 ▌标准入户门洞0.9m*2m， ▌房间门洞0.9m*2m， ▌厨房门洞0.8m*2m， ▌卫生间门洞0.7m*2m ▌客厅：长沙发：240*90*75cm长方形茶几：130*70*45cm电视柜：200*50*180cm电视离沙发：3m电视高度与电视柜高差：40到120cm走道宽度：100至120cm ▌厨房：橱柜操作台：台面高80cm左右面积90*46（最小20最大60）cm吊柜：离台面60cm左右高度在145cm到150cm餐桌：餐桌高：750—790mm。餐椅高；450—500mm。圆桌直径：二人500mm．二人800mm，四人900mm，五人1100mm，六人1100-1250mm，八人1300mm，十人l500mm，十二人1800mm。方餐桌尺寸：二人700×850(mm)，四人1350×850(mm)，八人2250×850(mm) ▌卫生间：浴缸长度：一般有三种1220、1520、1680mm；宽：720mm，高：450mm。坐便：750×350(mm)。冲洗器：690×350(mm)。盟洗盆：550×410(mm)。淋浴器高：2100mm。化妆台：长：1350mm；宽450mm。 ▌卧室：标准双人床尺寸：150*190、150*200厘米，被套的尺寸应配180*215和200*230之间的。加大双人床尺寸：180*200厘米，被套一般为200*230或220*240。床头柜宽：400毫米-600毫米，深：350毫米-450毫米高：500毫米-700毫米。衣柜：柜门尺寸，单
USB设备驱动程序设计 引言 USB 总线是1995 年微软、IBM 等公司推出的一种新型通信标准总线， 特点是速度快、价格低、独立供电、支持热插拔等，其版本从早期的1.0、1.1 已经发展到目前的2.0 版本，2.0 版本的最高数据传输速度达到480Mbit/s，能 满足包括视频在内的多种高速外部设备的数据传输要求，由于其众多的优点，USB 总线越来越多的被应用到计算机与外设的接口中，芯片厂家也提供了多种USB 接口芯片供设计者使用，为了开发出功能强大的USB 设备，设计者往往 需要自己开发USB 设备驱动程序，驱动程序开发一直是Windows 开发中较难 的一个方面，但是通过使用专门的驱动程序开发包能减小开发的难度，提高工 作效率，本文使用Compuware Numega 公司的DriverStudio3.2 开发包，开发了基于NXP 公司USB2.0 控制芯片ISP1581 的USB 设备驱动程序。 USB 设备驱动程序的模型 USB 设备驱动程序是一种典型的WDM(Windows Driver Model)驱动程序，其程序模型如图1 所示。用户应用程序工作在Windows 操作系统的用户模式层，它不能直接访问USB 设备，当需要访问时，通过调用操作系统的 API(Application programming interface)函数生成I/O 请求信息包(IRP)，IRP 被传输到工作于内核模式层的设备驱动程序，并通过驱动程序完成与UBS 外设通 信。设备驱动程序包括两层：函数驱动程序层和总线驱动程序层，函数驱动程 序一方面通过IRP 及API 函数与应用程序通信，另一方面调用相应的总线驱动 程序，总线驱动程序完成和外设硬件通信。USB 总线驱动程序已经由操作系统 提供，驱动程序开发的重点是函数驱动程序。 USB 设备驱动程序的设计
家具设计的基本尺寸（单位：cm） 衣橱：深度：一般60~65；推拉门：70，衣橱门宽度：40~65 推拉门：75~150，高度：190~240 矮柜：深度：35~45，柜门宽度：30-60 电视柜：深度：45-60，高度：60-70 单人床：宽度：90，105，120；长度：180，186，200，210 双人床：宽度：135，150，180；长度180，186，200，210 圆床：直径：186，212.5，242.4（常用） 室内门：宽度：80-95，医院120；高度：190，200，210，220，240 厕所、厨房门：宽度：80，90；高度：190，200，210 窗帘盒：高度：12-18；深度：单层布12；双层布16-18（实际尺寸） 沙发：单人式：长度：80-95，深度：85-90；坐垫高：35-42；背高：70-90 双人式：长度：126-150；深度：80-90 三人式：长度：175-196；深度：80-90 四人式：长度：232-252；深度80-90 茶几：小型，长方形：长度60-75，宽度45-60，高度38-50（38最佳） 中型，长方形：长度120-135；宽度38-50或者60-75 正方形：长度75-90，高度43-50 大型，长方形：长度150-180，宽度60-80，高度33-42（33最佳） 圆形：直径75，90，105，120；高度：33-42 方形：宽度90，105，120，135，150；高度33-42 书桌：固定式：深度45-70（60最佳），高度75 活动式：深度65-80，高度75-78 书桌下缘离地至少58；长度：最少90（150-180最佳） 餐桌：高度75-78（一般），西式高度68-72，一般方桌宽度120，90，75；长方桌宽度80，90，105，120；长度150，165，180，210，240 圆桌：直径90，120，135，150，180 书架：深度25-40（每一格），长度：60-120；下大上小型下方深度35-45，高度80-90活动未及顶高柜：深度45，高度180-200 木隔间墙厚：6-10；内角材排距：长度（45-60）*90
系泊系统的设计和探究 This model paper was revised by the Standardization Office on December 10, 2020
赛区评阅编号（由赛区组委会填写）： 2016年高教社杯全国大学生数学建模竞赛 承诺书 我们仔细阅读了《全国大学生数学建模竞赛章程》和《全国大学生数学建模竞赛参赛规则》（以下简称为“竞赛章程和参赛规则”，可从全国大学生数学建模竞赛网站下载）。 我们完全明白，在竞赛开始后参赛队员不能以任何方式（包括电话、电子邮件、网上咨询等）与队外的任何人（包括指导教师）研究、讨论与赛题有关的问题。 我们知道，抄袭别人的成果是违反竞赛章程和参赛规则的，如果引用别人的成果或资料（包括网上资料），必须按照规定的参考文献的表述方式列出，并在正文引用处予以标注。在网上交流和下载他人的论文是严重违规违纪行为。 我们以中国大学生名誉和诚信郑重承诺，严格遵守竞赛章程和参赛规则，以保证竞赛的公正、公平性。如有违反竞赛章程和参赛规则的行为，我们将受到严肃处理。 我们授权全国大学生数学建模竞赛组委会，可将我们的论文以任何形式进行公开展示（包括进行网上公示，在书籍、期刊和其他媒体进行正式或非正式发表等）。 我们参赛选择的题号（从A/B/C/D中选择一项填写）： 我们的报名参赛队号（12位数字全国统一编号）： 参赛学校（完整的学校全称，不含院系名）： 参赛队员 (打印并签名) ：1.
2. 3. 指导教师或指导教师组负责人 (打印并签名)： （指导教师签名意味着对参赛队的行为和论文的真实性负责） 日期：年月日 （请勿改动此页内容和格式。此承诺书打印签名后作为纸质论文的封面，注意电子版论文中不得出现此页。以上内容请仔细核对，如填写错误，论文可能被取消评奖资格。） 赛区评阅编号（由赛区组委会填写）： 2016年高教社杯全国大学生数学建模竞赛 编号专用页 赛区评阅记录（可供赛区评阅时使用）： 送全国评阅统一编号（赛区组委会填写）： 全国评阅随机编号（全国组委会填写）：
最新开发usb驱动程序的方法连载一 开发usb驱动程序的方法（连载二） NT还有更多其他的对象，例如中断对象、Controller对象、定时器对象等等，但在我们开发的驱动程序中并没有用到，因此在这里不做介绍。 I/O缓冲策略 很明显的，驱动程序和客户应用程序经常需要进行数据交换，但我们知道驱动程序和客户应用程序可能不在同一个地址空间，因此操作系统必须解决两者之间的数据交换。这就就设计到设备的I/O缓冲策略。 读写请求的I/O缓冲策略 前面说到通过设置Device对象的Flag可以选择控制处理读写请求的I/O缓冲策略。下面对这些缓冲策略分别做一介绍。 1、缓冲I/O(DO_BUFFERED_IO) 在读写请求的一开始，I/O管理器检查用户缓冲区的可访问性，然后分配与调用者的缓冲区一样大的非分页池，并把它的地址放在IRP的AssociatedIrp.SystemBuffer域中。驱动程序就利用这个域来进行实际数据的传输。 对于IRP_MJ_READ读请求，I/O管理器还把IRP的UserBuffer域设置成调用者缓冲区的用户空间地址。当请求完成时，I/O管理器利用这个地址将数据从驱动程序的系统空间拷贝回调用者的缓冲区。对于IRP_MJ_WRITE写请求，UserBuffer被设置为NULL，并把用户缓冲区的数据拷贝到系统缓冲区中。 2、直接I/O(DO_DIRECT_IO) I/O管理器首先检查用户缓冲区的可访问性，并在物理内存中锁定它。然后它为该缓冲区创建一个内存描述表(MDL)，并把MDL的地址存放在IRP的MdlAddress域中。AssociatedIrp.SystemBuffer和 UserBuffer 都被设置为NULL。驱动程序可以调用函数 MmGetSystemAddressForMdl得到用户缓冲区的系统空间地址，从而进行数据操作。这个函数将调用者的缓冲区映射到非份页的地址空间。驱动程序完成I/O请求后，系统自动从系统空间解除缓冲区的映射。 3、这两种方法都不是 这种情况比较少用，因为这需要驱动程序自己来处理缓冲问题。 I/O管理器仅把调用者缓冲区的用户空间地址放到IRP的UserBuffer 域中。我们并不推荐这种方式。 IOCTL缓冲区的缓冲策略 IOCTL请求涉及来自调用者的输入缓冲区和返回到调用者的输出缓冲区。为了理解IOCTL请求，我们先来看看WIN32 API DeviceIoControl函数的原型。 BOOL DeviceIoControl ( HANDLE hDevice, // 设备句柄 DWORD dwIoControlCode, // IOCTL请求操作代码 LPVOID lpInBuffer, // 输入缓冲区地址 DWORD nInBufferSize, // 输入缓冲区大小 LPVOID lpOutBuffer, // 输出缓冲区地址 DWORD nOutBufferSize, // 输出缓冲区大小 LPDWORD lpBytesReturned, // 存放返回字节数的指针
家具设计的基本尺寸（单位：厘米） 衣橱：深度：一般60~65；推拉门：70，衣橱门宽度：40~65 推拉门：75~150，高度：190~240 矮柜：?深度：35~45，柜门宽度：30-60 电视柜：深度：45-60，高度：60-70 单人床：宽度：90，105，120；长度：180，186，200，210 双人床：宽度：135，150，180；长度180，186，200，210 圆床：?直径：186，，（常用） 室内门：宽度：80-95，医院120；高度：190，200，210，220，240 厕所、厨房门：宽度：80，90；高度：190，200，210 窗帘盒：高度：12-18；深度：单层布12；双层布16-18（实际尺寸） 沙发：单人式：长度：80-95，深度：85-90；坐垫高：35-42；背高：70-90双人式：长度：126-150；深度：80-90 三人式：长度：175-196；深度：80-90 四人式：长度：232-252；深度80-90 茶几：小型，长方形：长度60-75，宽度45-60，高度38-50（38最佳） 中型，长方形：长度120-135；宽度38-50或者60-75 正方形：?长度75-90，高度43-50 大型，长方形：长度150-180，宽度60-80，高度33-42（33最佳）
圆形：直径75，90，105，120；高度：33-42 方形：宽度90，105，120，135，150；高度33-42 书桌：固定式：深度45-70（60最佳），高度75 活动式：深度65-80，高度75-78 书桌下缘离地至少58；长度：最少90（150-180最佳） 餐桌：高度75-78（一般），西式高度68-72，一般方桌宽度120，90，75； 长方桌宽度80，90，105，120；长度150，165，180，210，240 圆桌：直径90，120，135，150，180 书架：深度25-40（每一格），长度：60-120；下大上小型下方深度35-45，高度80-90 活动未及顶高柜：深度45，高度180-200 木隔间墙厚：6-10；内角材排距：长度（45-60）*90 桌类家具高度尺寸：７００ｍｍ、７２０ｍｍ、７４０ｍｍ、７６０ｍｍ四个规格； 椅凳类家具的座面高度：４００ｍｍ、４２０ｍｍ、４４０ｍｍ三个规格。 桌椅高度差应控制在２８０至３２０ｍｍ范围内。
开发usb驱动程序的方法（连载一） 开始驱动程序设计 下面的文字是从Microsoft的DDK帮助中节选出来的，它让我们明白在开始设计驱动程序应该注意些什么问题，这些都是具有普遍意义的开发准则。应该支持哪些I/O请求在开始写任何代码之前，应该首先确定我们的驱动程序应该处理哪些IRP例程。 如果你在设计一个设备驱动程序，你应该支持和其他相同类型设备的NT驱动程序相同的IRP_MJ_XXX 和IOCTL请求代码。 如果你是在设计一个中间层NT驱动程序，应该首先确认你下层驱动程序所管理的设备，因为一个高层的驱动程序必须具有低层驱动程序绝大多数IRP_MJ_XXX例程入口。高层驱动程序在接到I/O 请求时，在确定自身IRP当前堆栈单元参数有效的前提下，设置好IRP中下一个低层驱动程序的堆栈单元，然后再调用IoCallDriver 将请求传递给下层驱动程序处理。 一旦决定好了你的驱动程序应该处理哪些IRP_MJ_XXX，就可以开始确定驱动程序应该有多少个Dispatch例程。当然也可以考虑把某些 RP_MJ_XXX处理的例程合并为同一例程处理。例如在ChangerDisk 和 VDisk里，对IRP_MJ_CREATE和IRP_MJ_CLOSE处理的例程就是同一函数。对IRP_MJ_READ和IRP_MJ_WRITE处理的例程也是同一个函数。 应该有多少个Device对象？ 一个驱动程序必须为它所管理的每个可能成为I/O请求的目标的物理和逻辑设备创建一个命名Device对象。一些低层的驱动程序还可能要创建一些不确定数目的Device对象。例如一个硬盘驱动程序必须为每一个物理硬盘创建一个Device对象，同时还必须为每个物理磁盘上的每个逻辑分区创建一个Device对象。一个高层驱动驱动程序必须为它所代表的虚拟设备创建一个Device 对象，这样更高层的驱动程序才能连接它们的Device对象到这个驱动程序的Device对象。另外，一个高层驱动程序通常为它低层驱动程序所创建的Device对象创建一系列的虚拟或逻辑Device对象。 尽管你可以分阶段来设计你的驱动程序，因此一个处在开发阶段的驱动程序不必一开始就创建出所有它将要处理的所有Device对象。但从一开始就确定好你最终要创建的所有Device对象将有助于设计者所要解决的任何同步问题。另外，确定所要创建的Device对象还有助于你定义Device对象的Device Extension 的内容和数据结构。 开始驱动程序开发 驱动程序的开发是一个从粗到细逐步求精的过程。NT DDK的src\ 目录下有一个庞大的样板代码，几乎覆盖了所有类型的设备驱动程序、高层驱动程序和过滤器驱动程序。在开始开发你的驱动程序之前，你应该在这个样板库下面寻找是否有和你所要开发的类似类型的例程。例如我们所开发的驱动程序，虽然DDK 对USB描述得不是很详细，我们还是可以在src\storage\class目录发现很多和USB设备有关的驱动程序。下面我们来看开发驱动程序的基本步骤。 最简的驱动程序框架 1、写一个DriverEntry例程，在里面调用IoCreateDevice创建一个Device对象。 2、写一个处理IRP_MJ_CREA TE请求的Dispatch例程的基本框架 (参见DDK Kernel-Mode Drivers 4.4.3描述的一个DispatchCreate 例程所要完成的最基本工作。当然写了DispatchCreate例程后，要在DriverEntry 例程为IRP_MJ_CREA TE初始化例程入口)。如果驱动程序创建了多于一个Device对象，则必须为IRP_MJ_CLOSE 请求写一个例程，该例程通常情况下可以和DispatchCreate共用一个例程，参见参见DDK Kernel-Mode Drivers 4.4.3。 3、编译连接你的驱动程序。
提供全方位装修指南，装修设计知识、丰富设计案例！ 家装各种最佳尺寸标准大全! 家装最实际的规格尺寸 标准红砖24*11.5*53； 标准入户门洞0.9米*2米， 房间门洞0.9米*2米， 厨房门洞0.8米*2米， 卫生间门洞0.7米*2米， 标准水泥50kg/袋。 厨房 1.吊柜和操作台之间的距离应该是多少？ 60厘米。 从操作台到吊柜的底部，您应该确保这个距离。这样，在您可以方便烹饪的同时，还可以在吊柜里放一些小型家用电器。 2.在厨房两面相对的墙边都摆放各种家具和电器的情况下，中间应该留多大的距离才不会影响在厨房里做家务？ 120厘米。 为了能方便地打开两边家具的柜门，就一定要保证至少留出这样的距离。 150厘米。 这样的距离就可以保证在两边柜门都打开的情况下，中间再站一个人。 3.要想舒服地坐在早餐桌的周围，凳子的合适高度应该是多少？ 80厘米。 对于一张高110厘米的早餐桌来说，这是摆在它周围凳子的理想高度。因为在桌面和凳子之间还需要30厘米的空间来容下双腿。 4.吊柜应该装在多高的地方？ 145至150厘米。
提供全方位装修指南，装修设计知识、丰富设计案例！ 餐厅 1. 一个供六个人使用的餐桌有多大？ 2. 120厘米。 这是对圆形餐桌的直径要求。 140*70厘米。 这是对长方形和椭圆形捉制的尺寸要求。 2.餐桌离墙应该有多远？ 80厘米。 这个距离是包括把椅子拉出来，以及能使就餐的人方便活动的最小距离。 3.一张以对角线对墙的正方形桌子所占的面积要有多大？ 180*180平方厘米。 这是一张边长90厘米，桌角离墙面最近距离为40厘米的正方形桌子所占的最小面积。 4.桌子的标准高度应是多少？ 72厘米。 这是桌子的中等高度，而椅子是通常高度为45厘米。 5.一张供六个人使用的桌子摆起居室里要占多少面积？ 300*300厘米。 需要为直径120厘米的桌子留出空地，同时还要为在桌子四周就餐的人留出活动空间。这个方案适合于那种大客厅，面积至少达到600*350厘米。 6.吊灯和桌面之间最合适的距离应该是多少？ 70厘米。 这是能使桌面得到完整的、均匀照射的理想距离。 卫生间 1．卫生间里的用具要占多大地方？ 马桶所占的一般面积： 37厘米×60厘米。
U S B驱动程序的编写采用W D M驱动程序 Document serial number【UU89WT-UU98YT-UU8CB-UUUT-UUT108】
USB驱动程序的编写采用WDM 驱动程序。WDM 驱动程序是一些例程的集合，它们被动地存在，等待主机系 统软件（PnP 管理器、I/O 管理器、电源管理器等）来调用或激活它们。具体驱动程序不同，其所包含 的例程也不同。一个WDM 驱动程序的基本组成包括以下5个例程：（1）驱动程序入口例程：处理驱动程序的初始化。 （2）即插即用例程：处理PnP 设备的添加、删除和停止。 （3）分发例程：处理用户应用程序发出的各种 I/O 请求。 （4）电源管理例程：处理电源管理请求。 （5）卸载例程：处理驱动程序的卸载。 包含文件： , , , , , makefile,sources) 在文件中，包含了上述五个例程： 中定义了各种数据结构还有各种IOCTL控制码，用于不同数据的读写。
中实现了各种驱动例程。包含了上述五个所说例程外还包含了其他例程，课程从下面的驱动 程序入口例程得出一些信息。 驱动程序入口例程： NTSTATUS DriverEntry( IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING RegistryPath ) { NTSTATUS ntStatus = STATUS_SUCCESS; PDEVICE_OBJECT deviceObject = NULL; DriverObject->MajorFunction[IRP_MJ_CREATE] = Ezusb_Create; DriverObject->MajorFunction[IRP_MJ_CLOSE] = Ezusb_Close; ources. If you want to add a new source # file to this
【精华】室内装修，必须预留的最佳尺寸标准大全 2014-08-29筑龙房地产筑龙房地产 阅读引语 强烈推荐大家存的一份装修预留尺寸标准！！非常实用！！ 现在新房子的设计一般都会交给专门的设计师来做，但哪怕是专业设计师制作的设计图稿，没有实地接触的设计师可能还会存在一些设计尺寸上的死角。另 外，落实图稿的是施工队的工人，工人往往疏忽大意就会犯错。于是房子装修完了，总是小错误不断。因此小哥觉得大家有必要存一份尺寸标准，监工时要用起来 哦！且看且分享吧！ PART1：【客 厅】 【面积：20平方米～40平方米】 客厅是居室的门面，可以说对家具尺寸的要求是最严格的，多大的沙发配多大的茶几，多远的距离适合摆放电视等等，别看都是一些小数字，却足以令你的客厅成为一个舒适协调的地方。
电视组合柜的最小尺寸？ 【200×50×180厘米】 对于小户型的客厅，电视组合柜是非常实用的，这种类型的家具一般都是由大小不同的方格组成，上部比较适合摆放一些工艺品，柜体厚度至少要保持30厘米；而下部摆放电视的柜体厚度则至少要保持50厘米，同时在选购电视柜时也要考虑组合柜整体的高度和横宽与墙壁的面宽是否协调。 长沙发或是扶手沙发的椅背应该有多高？ 【85至90厘米】 沙发是用来满足人们的放松与休息的需求，所以舒适度是最重要的，这样的高度可以将头完全放在*背上，让颈部得到充分放松。如果沙发的*背和扶手过低，建议增加一个*垫来获得舒适度，如果空间不是特别宽敞，沙发应该尽量靠墙摆放。 扶手沙发与电视机之间应该预留多大的距离？
【3米左右】 这里所指的是在一个29英寸的电视与扶手沙发或和长沙发之间最短的距离，此外，摆放电视机的柜面高度应该在40厘米到120厘米之间，这样才能让看者非常舒适。 与容纳三个人的沙发搭配，多大的茶几合适呢？ 【120×70×45厘米或100×100×45厘米】 在沙发的体积很大或是两个长沙发摆在一起的情况下，矮茶几就是很好的选择，茶几的高度最好和沙发坐垫的位置持平。 目前市场上较为流行的是一种低矮的方几，材质多为实木或实木贴皮的，质感较好。 细节补充： 照明灯具距桌面的高度，白炽灯泡60瓦为100厘米，40瓦为65厘米，25瓦为50厘米，15瓦为30厘米；日光灯距桌面高度，40瓦为150厘米，30瓦为140厘米，20瓦为110厘米，8瓦为55厘米。 PART2：【餐 厅】 【面积：10平方米～20平方米】 用餐的地方是一家人团聚最多的地方，通常也是居室中较为拥挤的一个空间，因为有较多的餐椅需要放置，也是家人同时集中的地方，所以它的尺寸就更要精打细算才能使餐厅成为一个温馨的地方。
摘要 本题要求观测近海观测网的组成，建立模型对其中系泊系统进行设计，在不同风速和水流的情况下确定锚链，重物球，钢管及浮标等的状态，从而使通讯设备的工作效果最佳。求解的具体流程如下： 针对问题一，分别对系统中的受力物体在水平方向和竖直方向上的力进行分析，找出锚链对锚无拉力时的临界风速，运用力矩平衡求出钢管与钢桶的倾斜角度。对于锚链，将其等效为悬链线模型，根据风速不同判断锚链的状态，从而求出结果。 ?时能够正常工针对问题二，需要调节重物球的质量，使通讯设备在36m m 作。为了确定重物球的质量，首先将实际风速与临界风速进行比较，判断此时系统中各物体的状态，与题目中已知数据进行比较。在钢桶倾斜角度达到临界角度时，计算锚链与海床的夹角并于题中数据进行比较，计算重物球的质量。在浮标完全没入海面时，计算相应条件下重物球的质量，从而确定满足条件的重物球的质量范围。 针对问题三，要求在不同条件下，求出系泊系统中各物体的状态。以型号I 锚链为例，当水流方向与风速方向相同时，系统条件最差，分析在不同水深条件下的系泊系统设计。由题中已知条件确定系统设计的限制条件，对系统各物体进行受力分析，以使整体结果最小，即可得出最优的系泊系统设计。 # 》 关键词：悬链线多目标非线性规划 @
一、问题重述 近浅海观测网的传输节点由浮标系统、系泊系统和水声通讯系统组成（如图1所示）。某型传输节点的浮标系统可简化为底面直径2m、高2m的圆柱体，浮标的质量为1000kg。系泊系统由钢管、钢桶、重物球、电焊锚链和特制的抗拖移锚组成。锚的质量为600kg，锚链选用无档普通链环，近浅海观测网的常用型号及其参数在附表中列出。钢管共4节，每节长度1m，直径为50mm，每节钢管的质量为10kg。要求锚链末端与锚的链接处的切线方向与海床的夹角不超过16度，否则锚会被拖行，致使节点移位丢失。水声通讯系统安装在一个长1m、外径30cm 的密封圆柱形钢桶内，设备和钢桶总质量为100kg。钢桶上接第4节钢管，下接电焊锚链。钢桶竖直时，水声通讯设备的工作效果最佳。若钢桶倾斜，则影响设备的工作效果。钢桶的倾斜角度（钢桶与竖直线的夹角）超过5度时，设备的工作效果较差。为了控制钢桶的倾斜角度，钢桶与电焊锚链链接处可悬挂重物球。 系泊系统的设计问题就是确定锚链的型号、长度和重物球的质量，使得浮标的吃水深度和游动区域及钢桶的倾斜角度尽可能小。 问题1某型传输节点选用II型电焊锚链，选用的重物球的质量为1200kg。现将该型传输节点布放在水深18m、海床平坦、海水密度为×103kg/m3的海域。若海水静止，分别计算海面风速为12m/s和24m/s时钢桶和各节钢管的倾斜角度、锚链形状、浮标的吃水深度和游动区域。 | 问题2在问题1的假设下，计算海面风速为36m/s时钢桶和各节钢管的倾斜角度、锚链形状和浮标的游动区域。请调节重物球的质量，使得钢桶的倾斜角度不超过5度，锚链在锚点与海床的夹角不超过16度。 问题3 由于潮汐等因素的影响，布放海域的实测水深介于16m~20m之间。布放点的海水速度最大可达到s、风速最大可达到36m/s。请给出考虑风力、水流力和水深情况下的系泊系统设计，分析不同情况下钢桶、钢管的倾斜角度、锚链形状、浮标的吃水深度和游动区域。 二、模型假设 1.不考虑流体对锚链的作用，忽略锚链本身的伸长，锚链沿长度均匀分布； 2.假设风是二维的，只存在平行于水平面的风速，不存在垂直方向上的分量；
编写USB驱动程序步骤： 1所有usb驱动都必须创建主要结构体struct usb_driver struct usb_driver ->struct module *owner (有他可正确对该驱动程序引用计数，应为THIS_MODULE） ->const char *name (驱动名字，运行时可在查看 /sys/bus/usb/drivers/) ->const struct usb_device_id *id_table (包含该驱动可支持的所有不同类型的驱动设备,没添探测回调函数不会被调用） ->int （*probe)(struct usb_interface *intf,const struct usb_device_id *id) (usb驱动探测函数,确认后struct usb_interface 应恰当初始化，然后返0，如果出错则返负值) ->void(*disconnect)(struct usb_interface *intf) (当struct usb_interface 被从系统中移除或驱动正从usb核心中卸载时，usb核心将调用此函数）代码实例： static struct usb_driver skel_driver={ .owner = THIS_MODULE, .name = "skeleton", .id_table = skel_table, .probe = skel_probe, .disconnect = skel_disconnect, }; ↓ 2usb_register()注册将struct usb_driver 注册到usb核心，传统是在usb驱动程序模块初始化代码中完成该工作的
家具设计地基本尺寸（单位：） 衣橱：深度：一般；推拉门：，衣橱门宽度： 推拉门：，高度： 矮柜：深度：，柜门宽度： 电视柜：深度：，高度： 单人床：宽度：，，；长度：，，， 双人床：宽度：，，；长度，，， 圆床：直径：，，（常用） 室内门：宽度：，医院；高度：，，，， 厕所、厨房门：宽度：，；高度：，， 窗帘盒：高度：；深度：单层布；双层布（实际尺寸） 沙发：单人式：长度：，深度：；坐垫高：；背高： 双人式：长度：；深度： 三人式：长度：；深度： 四人式：长度：；深度 茶几：小型，长方形：长度，宽度，高度（最佳） 中型，长方形：长度；宽度或者 正方形：长度，高度 大型，长方形：长度，宽度，高度（最佳） 圆形：直径，，，；高度： 方形：宽度，，，，；高度 书桌：固定式：深度（最佳），高度 活动式：深度，高度 书桌下缘离地至少；长度：最少（最佳） 餐桌：高度（一般），西式高度，一般方桌宽度，，；长方桌宽度，，，；长度，，，，圆桌：直径，，，， 书架：深度（每一格），长度：；下大上小型下方深度，高度 活动未及顶高柜：深度，高度 木隔间墙厚：；内角材排距：长度（）* 室内常用尺寸 、墙面尺寸 ()踢脚板高；—. ()墙裙高：—. ()挂镜线高：—(画中心距地面高度). ．餐厅
() 餐桌高：—. () 餐椅高；—. () 圆桌直径：二人．二人，四人，五人，六人，八人，十人，十二人. () 方餐桌尺寸：二人×()，四人×()，八人×()， () 餐桌转盘直径；—. 餐桌间距：(其中座椅占)应大于. () 主通道宽：—. 内部工作道宽：—. () 酒吧台高：—，宽. () 酒吧凳高；一. 在客厅 .长沙发与摆在它面前地茶几之间地正确距离是多少？ 厘米 在一个（**高厘米）地长沙发面前摆放一个（**高厘米）地长方形茶几是非常舒适地.两者之间地理想距离应该是能允许你一个人通过地同时又便于使用，也就是说不用站起来就可以方便地拿到桌上地杯子或者杂志. b5E2R。 .一个能摆放电视机地大型组合柜地最小尺寸应该是多少？ **高厘米 这种类型地家具一般都是由大小不同地方格组成，高处部分比较适合用来摆放书籍，柜体厚度至少保持厘米；而低处用于摆放电视地柜体厚度至少保持厘米.同时组合柜整体地高度和横宽还要考虑与墙壁地面积相协调..如果摆放可容纳三、四个人地沙发，那么应该选择多大地茶几来搭配呢？ **高厘米 在沙发地体积很大或是两个长沙发摆在一起地情况下，矮茶几就是很好地选择，高度最好和沙发坐垫地位置持平. .在扶手沙发和电视机之间应该预留多大地距离？ 米 这里所指地是在一个英寸地电视与扶手沙发或长沙发之间最短地距离.此外，摆放电视机地柜面高度应该在厘米到厘米之间，这样才能使观众保持正确地坐姿. .摆在沙发边上茶几地理想尺寸是多少？ 方形：**高厘米. 椭圆形：*高厘米. 放在沙发边上地咖啡桌应该有一个不是特别大地桌面，但要选那种较高地类型，这样即使坐着地时候也能方便舒适地取到桌上地东西. p1Ean。 .两个面对面放着地沙发和摆放在中间地茶几一共需要占据多大地空间？ 两个双人沙发（规格 **高厘米）和茶几（规格**高厘米）之间应相距厘米. .长沙发或是扶手沙发地地靠背应该有多高？
数学建模A题系泊系统 设计 HEN system office room 【HEN16H-HENS2AHENS8Q8-HENH1688】
系泊系统的设计 摘要 本题要求观测近海观测网的组成，建立模型对其中系泊系统进行设计，在不同风速和水流的情况下确定锚链，重物球，钢管及浮标等的状态，从而使通讯设备的工作效果最佳。求解的具体流程如下： 针对问题一，分别对系统中的受力物体在水平方向和竖直方向上的力进行分析，找出锚链对锚无拉力时的临界风速，运用力矩平衡求出钢管与钢桶的倾斜角度。对于锚链，将其等效为悬链线模型，根据风速不同判断锚链的状态，从而求出结果。 ?时能够正常工作。为针对问题二，需要调节重物球的质量，使通讯设备在36m m 了确定重物球的质量，首先将实际风速与临界风速进行比较，判断此时系统中各物体的状态，与题目中已知数据进行比较。在钢桶倾斜角度达到临界角度时，计算锚链与海床的夹角并于题中数据进行比较，计算重物球的质量。在浮标完全没入海面时，计算相应条件下重物球的质量，从而确定满足条件的重物球的质量范围。 针对问题三，要求在不同条件下，求出系泊系统中各物体的状态。以型号I锚链为例，当水流方向与风速方向相同时，系统条件最差，分析在不同水深条件下的系泊系统设计。由题中已知条件确定系统设计的限制条件，对系统各物体进行受力分析，以使整体结果最小，即可得出最优的系泊系统设计。 关键词：悬链线多目标非线性规划 一、问题重述 近浅海观测网的传输节点由浮标系统、系泊系统和水声通讯系统组成（如图1所示）。某型传输节点的浮标系统可简化为底面直径2m、高2m的圆柱体，浮标的质量为1000kg。系泊系统由钢管、钢桶、重物球、电焊锚链和特制的抗拖移锚组成。锚的质量为600kg，锚链选用无档普通链环，近浅海观测网的常用型号及其参数在附表中列出。钢管共4节，每节长度1m，直径为50mm，每节钢管的质量为10kg。要求锚链末端与锚的链接处的切线方向与海床的夹角不超过16度，否则锚会被拖行，致使节点移位丢失。水声通讯系统安装在一个长1m、外径30cm的密封圆柱形钢桶内，设备和钢桶总质量为100kg。钢桶上接第4节钢管，下接电焊锚链。钢桶竖直时，水声通讯设备的工作效果最佳。若钢桶倾斜，则影响设备的工作效果。钢桶的倾斜角度（钢桶与竖直线的夹角）超过5度时，设备的工作效果较差。为了控制钢桶的倾斜角度，钢桶与电焊锚链链接处可悬挂重物球。 系泊系统的设计问题就是确定锚链的型号、长度和重物球的质量，使得浮标的吃水深度和游动区域及钢桶的倾斜角度尽可能小。