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毕业论文图片尺寸要求如下：
因学校和专业而异，但大多数学校对于毕业论文的图片要求都是较为严格的。通常，图片应该具有足够的分辨率和清晰度，以保证图片质量与整体论文风格一致。以下是详细解释：
1.学校要求
不同学校或专业对毕业论文图片的具体要求不尽相同。有一些学校规定了图片的像素和尺寸，通常要求图像分辨率不能低于300dpi，并限制了最大和最小宽度或高度值。
2.图片格式
通常来说，毕业论文要求使用JPG或PNG格式的图片。这两种格式的图片在保证高质量的情况下，可以控制文件大小和保持良好的压缩效果。尤其对于在线提交毕业论文的学校，要求的图片格式可能不同。
3.图片尺寸
毕业论文中的图片尺寸需要适应实际应用，即要对照教师或指导老师给的毕业论文要求，并参考大学期间的实验课、论文写作课等相关经验。
一些常用的图片尺寸包括：宽200像素，高150像素；宽400像素，高300像素；宽600像素，高450像素。另外，在插入大图时，应该经过压缩处理之后再放置到文中，以便控制图片大小和文件尺寸。
4.图片版式
毕业论文的图片还需要符合相关的版式要求。图片需要与论文正文相结合，同时也需要有明显的图例说明，不同来源的图片需要详细注明出处，以避免抄袭和知识产权问题。
附加知识
毕业论文是研究生和本科生毕业时必须完成的重要项目。它是学术研究和成果展示的体现，也是评价学生知识和能力的重要途径之一。
因此，无论是文献查阅、论文组织，还是图片处理、排版等方面，毕业论文都需要仔细地准备和编写。好的论文不仅是学生经过几年学习和实践积累的结晶，也是面对未来职业发展的有力证明。
这是我从一篇文章下摘录下来的，请参考！ 模板：①白底：可以选择黑字，红字和蓝字，如果你觉得不够丰富，你可以改变局部的底色。②蓝底：深蓝更好一点，白字或黄字（浅黄和橘黄）,深蓝背景下不要选择暗红。是最普遍最保险，也是最简单的配色方案。③黑底：白字和黄字（橘黄比浅黄好）。这三种配色方式可以保证你的幻灯质量，如果你是第一次做，强力建议。 或许你觉得这样的幻灯太单调了，其实不然，你的幻灯不应该只有文字，你可以用各种模式图或流程图，使你的幻灯增加色彩，你也可以加一点小小的花边，或者在标题和正文之间加一条线，或者插入学校图标，都可以使你的幻灯不再单调 幻灯片制作大忌： 1. 忌讳大量文字与数字堆砌：幻灯最好采用标题式，讲解时按照标题发挥。将表格转换为统计图（如直方图）更为直观。每页幻灯文字不宜多于10行，正文字号不宜小于5号。 2. 忌讳铺天盖地不留余地：幻灯片应适当留出边缘，忌讳每页幻灯片内容都塞得满满地，看了头也大了。 3. 忌讳过于单调与过分花哨：一个人穿上一身的朴素衣服显得单调，浑身上下都穿上花衣服也未必好看。幻灯的生动体现在背景与文字的颜色搭配、图片与动画的适当应用等诸多方面，关键是两个字－－“和谐” 幻灯制作必杀技巧： 在制作幻灯前，下列技巧你必须掌握： 1. 图片压缩与编辑：幻灯片中经常会用到位图和插图，扫描和部分下载的bmp图片太大，插入幻灯后将令幻灯立刻“肥胖”，你必须学会压缩为jpeg等格式，压缩和裁减图片使用acdsee等就可以搞定；当然，PowerPoint 2002可以在这方面为你效劳，在创建幻灯的过程中，用户可以随时通过调用"图像"工具条对一个或几个位图图片进行压缩，依次选择"视图">"工具?quot;>"图片"，点击工具条上的"压缩图片"按钮即可。 另外，很多网上下载的图片往往需要复杂修改，你当然必须掌握photoshop等软件；作为高手，往往还需要自己制作部分重要的矢量图，需要掌握一种相关软件。 2. 统计图表的制作：一般的图表在powpoint里面就可以搞定，需要标记标准差的直方图则需要在excel里进行编辑，复杂的统计图甚至需要在统计软件里搞定。 3. 插入多媒体与动画：如果你像为你的幻灯添加动感，你还必须掌握插入多媒体（如avi）和动画（如swf）的方法以及设置播放的技巧，如果你还不会，赶紧在网上看看教程或请教别人吧。 4. 其他文字与动画技巧：学会制作不断闪烁的文字或图案，定义动画，定义幻灯片切换方式等可以使你的幻灯更加生动。 www,
修改图片大小。使用修图软件，对图片的大小，颜色和分辨率进行调整，一般来说论文中引用的图片需要调整为灰度。论文中图片的位置:插入文章的各类型图都应居中，并按排版需要调整大小，但图片宽度不应超过正文文本宽度。颜色:除特殊用途图片外，插图尽量不使用彩色图，应调为灰度。
The Basics A jet engine can be divided into several distinct sections: intake, compressor, diffuser, combustion chamber, turbine, and exhaust. These sections are much like the different cycles in a four-stroke reciprocating engine: intake, compression, power and exhaust. In a four-stroke engine a fuel/air mixture is is brought into the engine (intake), compressed (compression), and finally ignited and pushed out the exhaust (power and exhaust). In it's most basic form, a jet engine works in much the same way. * Air comes in the front of the engine where it enters the compressor. The air is compressed by a series of small spinning blades aptly named compressor blades and leaves at a high pressure. The pressure ratio between the beginning and end of the compressor can be as much as 48:1, but almost always 12:1 or more. * The air now enters the diffuser, which is nothing more than an area where the air can expand and lower it's velocity, thus increasing its pressure a little bit more. * The high pressure air at the end of the diffuser now enters the combustion chamber where it is mixed with fuel, ignited and burned. * When the fuel/air mixture burns, the temperature increases (obviously) which makes the air expand. * This expanding gas drives a set of turbine blades located aft of the combustion chamber. At least some of these turbine blades are connected by a shaft to the compressor blades to drive them. Depending on the type of engine, there may be another set of turbine blades used to drive another shaft to do other things, such as turn a propeller or generator. * The left over energy not extracted by the turbine blades is pushed out the back of the engine (exhaust section) and creates thrust, usually used to drive an airplane forward. The types of jet engines include: * Turbojet * Turbofan * Turboprop * Turbo shaft Turbojet The turbojet is the simplest of them all, it is just as described in "The basics" section. This style was the first type of jet engine to be used in aircraft. It is a pretty primitive style used mostly in early military jet fighters such as the F-86. Its use was discontinued, for the most part, in favor of the more efficient turbofans. Actually, I should clarify that. Each type of engine is most efficient under certain conditions. Turbojets are most efficient at high altitudes and speeds above the speed of sound. See the diagram at the end of this page for relative efficiencies of each style engine. Turbofan Turbofans make up the majority of jet engines being produced and used today. A turbofan engine uses an extra set of turbine blades to drive a large fan, typically on the front of the engine. This fan differs from a propeller in that there are many small blades and they are inside of a duct. The fan sits just in front of the normal intake, some of the air driven by this fan will enter the engine, while the rest will go around the outside. The amount of air that bypasses the engine is different for each type of airplane. The different styles are called high and low bypass engines. Bypass ratio is the ratio of how much air goes through the fan, to how much goes through the engine. Typical bypass ratios would be 1:1 for a low bypass and 5:1 or more for a high bypass. Low bypass engines are more efficient at higher speeds, and are used on planes such as military aircraft, while high bypass engines are used in commercial airliners. Turboprop Turboprops are similar to turbofans in that they incorporate an extra set of turbine blades used to drive the propeller. Unlike the turbofan engines, nearly all the thrust produced by a turboprop is from the propellor, hardly any thrust comes from the exhaust. These engines are used mostly on smaller and slower planes such as commuter aircraft that fly to the smaller airports. As you can see from the efficiency chart below, turboprops are very efficient over a fairly wide range of speeds. They would probably be used more often on large transport aircraft, except for one problem: they have propellors. The general public does not like propellors, as they appear to be old-fashioned and unsafe. However, the military knows better and uses them on several large transport aircraft. Turbo shaft Turbo shaft engines are very similar to turboprop engines, but instead of driving a propellor, they are used to drive something else. Many helicopters use them to drive their rotors, and airliners and other large jets use them to generate electricity. Also, the Alaska Pipeline uses them at the pump stations to pump oil. Overall Overall the big difference between these engines is how they take a chunk of air and move it. Newton's third law states that Force equals mass times acceleration. Applying this to turbine engines: the turboprop takes a large chunk and accelerates it a little bit, while the turbojet takes a small chunk and accelerates the heck out of it, and the turbofan is somewhere in between these two. These different methods of moving air also have to do with how much noise each engine makes. The turbojet makes the most noise because there is a large difference in velocities of the blast of air coming out the exhaust and the surrounding air. The air from the fan on a turbofan engine "shields" the blast in the center by having the slower moving air from the fan surround it. Then the turboprop is the quietest of all because the air it's moving is relatively slow. A pressure - volume diagram (or a P-V diagram) is a useful tool in thermodynamics. In this case, it relates the pressure and volume of the gas moving through the engine at different stages. A P-V diagram can also be helpful in finding the work output of an engine. Work equals the integral of pressure with respect to volume. Or is simpler form, work equals the area enclosed in the diagram above. The above cycle is the Brayton cycle, or the cycle used by aircraft gas turbine engines. Explanation of the above cycle: * Air enters the inlet at point 1 at atmospheric pressure. * As this air passes through the compressor (from point 1 to 2), the pressure rises adiabatically (no heat enters or leaves the system). * Now the air enters the combustion chamber (from point 2 to 3), is mixed with fuel, and burned at a constant pressure. * Finally, the air goes through the turbine and out the exhaust (point 3 to 4) where the gases expand and do work. Thus, the pressure drops and the volume increases. The Compressor There are two main styles for turbine compressors: the axial and the centrifugal. The Axial Compressor * The axial type compressor is made up of many small blades, called rotor vanes, arranged in rows on a cylinder whose radius gets larger towards the back (as can be seen from the above picture). These blades act much like small propellors. * In between these rotor vanes are stator vanes which stay in a fixed spot and straighten the air coming out of the previous stage of rotor vanes before it enters the next stage. * On some newer engines, the angle of these stator vanes can be adjusted for optimum efficiency. * Each stage (1 row of rotor and stator vanes) generally provides for a pressure rise of about (so after the first stage, the pressure would be above atmospheric, after the second it would be , , etc...). The Centrifugal Compressor * Air enters the centrifugal compressor at the front and center. The blades then sling the air radially outwards where it is once again collected (at a higher pressure) before it enters the diffuser. * Pressure rise per stage is usually about 4 to 8:1 (higher than axial). These can be sombined in series (that is the exit of the first leads to the entrance of the next) to produce a greater pressure rise. But more than two stages is not practical. - Jet engines are rated in "pounds of thrust," while turboprops and turboshaft engines are rated in "shaft horsepower" (SHP). This is because it is difficult to hook up a dynamometer (power measuring device) to the column of air coming out of a jet engine, while it is easy to hook one to the shaft of a turboprop. - An equivalent measure to horsepower is thrust horsepower (THP). THP = (Thrust x MPH) / 375. or THP = SHP x 80% in the case of turboprop engines (the 80% is because the propeller "slips" a little in flight). - Exhaust gases exit the exhaust at upwards of 1000 mph or more and can use 1000 gallons of fuel/hour or more. - Turbine engines run lean. Unlike gasoline engines, turbines take in more air than they need for combustion. - Fuel can be injected into the exhaust section to burn with this unused air for extra thrust. This is called an afterburner. - A water/methanol mixture can be injected into the intake to increase the air density, and thus increase thrust. - Turbine engines can be built on a small scale as well. The turbine pictured below has a diameter of 4mm and runs at 500,000 rpm. It was built by at MIT for purposes of powering an aircraft with a wing span of about 5 inches that was projected to fly about 35 - 70 mph with a range of about 40 - 70 miles. micro turbine - The ignition system on turbine engines is only necessary for starting, afterwards it is self sustaining. In jets, the ignition system is also turned on for added saftey in "critical" stages of flight, such as takeoff and landing. - A device similar to a spark plug is used for the ignition process, but it has a larger gap. The spark is about 4 to 20 Joules (watts/second) at about 25000 volts and occurs between 1 and 2 times per second. - Turbine engines will run on just about anything, they prefer Jet-A (AKA diesel, kerosene, or home heating oil), but can burn unleaded, burbon, or even very finely powdered coal! - The above snowmachine uses an Allison turbine engine, a very common engine in helicopters (such as the Bell 206 Jet Ranger shown below). A lot of horsepower can be put into a small package! Note the intake and compressor are at the front of the engine, then the two side tubes take the compressed air and bring it around back to the combustion chamber and turbine and the exhaust exits out the middle. There are many engines out there with strange configurations like this. Communications Technology Your Rights and what the Data Protection Commissioner can do to help Right of Access The personal information to which you are entitled is that held on computer or in a manual filing system that facilitates access to information about you. You can make an access request to any organisation or any individual who has personal information about you. For example, you could make an access request to your doctor, your bank, a credit reference agency, a Government Department dealing with your affairs, or your employer. If you find out that information kept about you by someone else is inaccurate, you have a right to have that information corrected (or "rectified"). In some circumstances, you may also have the information erased altogether from the database - for example, if the body keeping the information has no good reason to hold it (. it is irrelevant or excessive for the purpose), or if the information has not been obtained fairly. You can exercise your right of rectification or erasure simply by writing to the body keeping your data. In addition, you can request a data controller to block your data . to prevent it from being used for certain purposes. For example, you might want your data blocked for research purposes where it held for other purposes. If an organisation holds your information for the purposes of direct marketing (such as direct mailing, or telephone marketing), you have the right to have your details removed from that database. This right is useful if you are receiving unwanted "junk mail" or annoying telephone calls from salespeople. You can exercise this right simply by writing to the organisation concerned. The organisation must write back to you within 40 days confirming that they have dealt with your request. Right to complain to the Data Protection Commissioner What happens if someone ignores your access request, or refuses to correct information about you which is inaccurate? If you are having difficulty in exercising your rights, or if you feel that any person or organisation is not complying with their responsibilities, then you may complain to the Data Protection Commissioner, Mr Mead, who will investigate the matter for you. The Commissioner has legal powers to ensure that your rights are upheld. The Data Protection Commissioner will help you to secure your rights: * with advice and information * by intervening directly on your behalf if you feel you have not been given satisfaction * by taking action against those failing to fulfil their obligations. SEE APPENDIX 2 FOR CASE STUDY Ergonomics Ergonomics (from Greek ergon work and nomoi natural laws) is the study of designing objects to be better adapted to the shape of the human body and/or to correct the user's posture. Common examples include chairs designed to prevent the user from sitting in positions that may have a detrimental effect on the spine, and the ergonomic desk which offers an adjustable keyboard tray, a main desktop of variable height and other elements which can be changed by the user. Ergonomics also helps with the design of alternative computer input devices for people who want to avoid repetitive strain injury or carpal tunnel syndrome. A normal computer keyboard tends to force users to keep their hands together and hunch their shoulders. To prevent the injuries, or to give relief to people who already have symptoms, special split keyboards, curved keyboards, not-really-keyboards keyboards, and other alternative input devices exist. Ergonomics is much larger than looking at the physiological and anatomical aspects of the human being. The psychology of humans is also a key element within the ergonomics discipline. This psychological portion of ergonomics is usually referred to as Human factors or Human factors engineering in the ., and ergonomics is the term used in Europe. Understanding design in terms of cognitive workload, human error, the way humans perceive their surrounds and, very importantly, the tasks that they undertake are all analysed by ergonomists. [IMAGE] With video conferencing consideration should be taken in positioning of camera and screens so as to avoid neck strain. Codec 1. (COder/DECoder or COmpressor/DECompressor) Hardware or software that encodes/compresses and decodes/decompresses audio and video data streams. The purpose of a codec is to reduce the size of digital audio samples and video frames in order to speed up transmission and save storage space. The goal of all codec designers is to maintain audio and video quality while compressing the binary data further. Speech codecs are designed to deal with the characteristics of voice, while audio codecs are developed for music. Codecs may also be able to transcode from one digital format to another; for example, from PCM audio to MP3 audio. The codec algorithms may be implemented entirely in a chip or entirely in software in which case the PC does all of the processing. They are also commonly implemented in both hardware and software where a sound card or video capture card performs some of the processing, and the main CPU does the rest. When analog signals are entered into a computer, cellphone or other device via a microphone or video source such as a VHS tape or TV, analog-to-digital converters create the raw digital audio samples and video frames. Speech, audio and video codecs are typically lossy codecs that compress data by altering the original format, which is why "codec" means "encoder/decoder" and "compressor/decompressor." If a codec uses only lossless compression in which the original data is restored exactly, then it would not be a coder/decoder. This is a subtle point, but the two meanings of the acronym have been confusing. LAN A local area network (LAN) is a computer network covering a local area, like a home, office or small group of buildings such as a college. The topology of a network dictates its physical structure. The generally accepted maximum size for a LAN is 1000m2. LANs are different from personal area networks (PANs), metropolitan area networks (MANs) or wide area networks (WANs). LANs are typically faster than WANs. The earliest popular LAN, ARCnet, was released in 1977 by Datapoint and was originally intended to allow multiple Datapoint 2200s to share disk storage. Like all early LANs, ARCnet was originally vendor-specific. Standardization efforts by the IEEE have resulted in the IEEE 802 series of standards. There are now two common wiring technologies for a LAN, Ethernet and Token Ring. Wireless technologies are starting to evolve and are convenient for mobile computer users. A number of network protocols may use the basic physical transport mechanism including TCP/IP. In this case DHCP is a convenient way to obtain an IP address rather than using fixed addressing. LANs can be interlinked by connections to form a Wide area network. A router is used to make the connection between LANs. WAN WANs are used to connect local area networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organisation and are private, others, built by Internet service providers provide connections from an organisation's LAN to the Internet. WANs are most often built of leased lines. At each end of the leased line, a router connects to the LAN on one side and a hub within the WAN on the other. A number of network protocols may use the basic physical transport mechanism including TCP/IP. Other protocols including and ATM. Frame relay can also be used for WANs. Ethernet Ethernet is normally a shared media LAN. All stations on the segment share the total bandwidth, which is either 10 Mbps (Ethernet), 100 Mbps (Fast Ethernet) or 1000 Mbps (Gigabit Ethernet). With switched Ethernet, each sender and receiver pair have the full using Ethernet the computers are usually wired to a hub or to a switch. This constitutes the physical transport mechanism. Fiber-optic Ethernet (10BaseF and 100BaseFX) is impervious to external radiation and is often used to extend Ethernet segments up to miles. Specifications exist for complete fiber-optic networks as well as backbone implementations. FOIRL (Fiber-Optic Inter Repeater Link) was an earlier standard that is limited to .6 miles distance.
一、概述 可编程控制器（PLC）是一种新型的通用控制装置，他将传统的继电器控制技术、计算机控制技术和通信技术融为一体，专为工业控制而设计，具有功能强、通用灵活、可靠性强、环境适应性好、编成简单、使用方便、体积小、重量轻、功耗低等一系列优点。近年来，随着可编程控制器的日渐成熟，越来越多设备的控制都采用PLC控制器来代替传统的继电器控制，并取得了很好的经济效益。空气压缩机使矿山生产重要的四大固定设备之一，它生产压缩空气，用以带动凿岩机、风动装岩机等设备及其他风动工具。其能否安全运行直接影响着煤矿生产的产量和效益问题。影响其安全生产的要素主要有空压机的超温、超压、断水、断油等因素。随着煤矿现代化的发展，矿山对矿山设备的要求越来越高,建设本质安全性矿山已成为煤矿生产建设的核心。矿山设备不断更新，不断进步，可靠性、易操作性、可监视性、易维护性等已是最基本的要求了。用继电器搭成的控制电路具有可靠性差、不易维护、不易监视，已不能适应当前的要求。现在迫切需要可靠性高、易维护、易操作、可监视并且价格不高这样的控制器来代替继电器搭成的电路。随着电子技术、软件技术、控制技术飞速发展，可编程控制器（PLC）发展迅猛，性能很高，价格较为合理，与继电器搭的控制电路比具有非常大的优势。许多矿山设备已选用了PLC来代替比较重要的设备控制。传统的保护主要采用分离仪表，其可靠性差、集程度低、费用高，不能有效的满足矿山设备投入的经济性和安全性的要求。本文笔者采用可编程控制器（PLC）作为核心控制器，通过检测仪器为PLC提供控制中所需要的信号参数对空压机进行自动巡回检测控制。进行监控的主要参数有空压机高低压缸温度、润滑油温度、电动机温度、风包温度、出水温度；高低压缸压力、风包压力、润滑油压力；高/低压、中/后冷却水断水检测等参数。二、控制功能和控制原理1. 保护控制功能⑴、 电机电流和电压的检测。⑵、 一二级缸、油压、风包压力检测。⑶、 一二级排气温度、油温、电机温度检测。⑷、 电动机的延时启动。⑸、 电机的无水运转。2. 保护控制原理在启动主机之前先将水源电磁阀和放空电磁阀都打开，在冷却水压和流量达到规定值条件下，可以进行空压机的空载起动，然后延时自动关闭放空电磁阀，空压机进行正常运行。启动时允许低油压启动，设置一定时间后对油压进行监控。在停机时，按复位按钮放空电磁阀打开，经30秒延时后切断主电源。实现空压机的停机，同时关闭水源电磁阀和放空电磁阀。在保户状态时，以上监控参数有一个在设定范围内发生故障，产生报警信号，同时打开放空电磁阀，压缩机减载运行，延时30秒故障不消除自动机停机。 ⑴. 控制分布图1-1压缩机控制分布图⑵. 控制通讯原理现场总线PROFIBUS可以实现数字和模拟输入/输出、智能信号装置和过程调节装置与可编程控制器PLC和PC之间的数据传输，把I/O通道分散到实际需要的现场设备附近。PROFIBUS一方面覆盖了传感器/执行器领域的通信要求，另一方面又具有单元级领域的所有通信网络通信功能。他支持高速的循环数据通信，以满足了实时监控的要求。1-2系统控制通讯图三、信号采集S7-200为每个本机数字量输入提供脉冲捕捉功能。脉冲捕捉功能允许PLC捕捉到持续时间很短的脉冲。而在扫描周期的开始，这些脉冲不是总能被CPU读到。当一个输入设置了脉冲捕捉功能时，输入端的状态变化被锁存并一直保持到下一个扫描循环刷新。这就确保了一个持续时间很短的脉冲被捕捉到并保持到S7-200读取输入点。本设计需对下列参数进行采集： (1)、压力信号分别为1级缸、2级缸及储风缸压力、润滑油压力4点； (2)、温度信号为1级缸排气温度、2级缸进气温度、风包温度、油温、电机温度以及冷却水出口温度共6点； (3)、电量信号为主电机电流1点，电源电压1点，共2个点。(4)、流量检测有高低/压端2点，中/后冷2点共4点。采集参数总计为4+6+2+4=16个。 对上述参数采集后，首先判断有关参数是否异常，然后形成动态数据表格进行实时巡回显示，并存储起来而供以后进行随机查询。四、系统软件设计本系统主要是以保护为主，根据《煤矿安全规程》的要求和空压机的保护原理，其控制的软件设计流如下。五、结束语该系统主要是以S7-200 为核心控制器，PROFIBUS作为通讯桥梁，通过检测元件为控制其提供检测信号，以此达到保护控制的目的。在本文的编写过程中，得到了张集矿机电科多位领导的大力支持，在此致以诚挚的谢意！同时感谢西门子（中国）有限公司自动化驱动集团提供的大量资料。
论文编号:JX235 所有图纸,任务书.论文字数:40706.页数:105摘 要 本设计主要是带式输送机全自动液压张紧装置的设计。它是在吸收国、内外输送机张紧技术的基础上，根据国内带式输送机的运行特点及要求研制的。它采用比例控制技术及可靠性较高的可编程控制技术，可以对张紧力进行多点控制，根据不同工作情况随时调节张紧力的大小。能最大程度的延长皮带的寿命，大大节约了成本。在设计中，用一个动滑轮使液压缸的行程减少了一半，避免使用行程较长的液压缸，减少了制造液压缸的难度。同时，系统中增加了若干个蓄能器，可以最大限度的吸收液压冲击，减小对皮带的冲击力提高胶带的使用寿命。本设计在总结其它常规皮带张紧装置的基础上,设计了能够满足皮带机的皮带长度变化较大时的皮带拉紧装置。此装置在皮带机启动阶段,能提供足够大的启动张力；启动完毕后, 又可使皮带的张力恢复到额定值以维持皮带机的正常运行。本文根据液压自动张紧装置的液压原理,详细阐述了自动张紧装置的结构组成、控制原理及功能特点,并阐明了控制系统的设计关键在于压力值和最大拉力值的设定。介绍了带式输送机运行系统要求,并运用PLC可编程控制技术对带式输送机的起动、制动和拉紧部分实时监控,完全实现了带式输送机自动控制运行方式,构成了一个高可靠性的设备运行控制系统。关键词：带式输送机； 自动液压张紧装置； 自动控制； 可编程控制PLCABSTRACT This design is mainly about full automatic hydraulic tension station for belt conveyer. It is designed on the foundation of opening technology in and outside, according to the domestic operation characteristic of belt conveyer and requirement. The equipment is also made on domestic belt-type conveyer movement characteristic and requestment. It uses the proportional control technology and the reliable higher programmable control technology, It may carry on the multi-spots control to strict the strength, adjusts pressing the strength size as necessary according to the different working can be the greatest degree lengthen the leather belt the life, greatly saved the cost. In the design, It causes the hydraulic cylinder with a movable pulley the stroke to reduce one half, and avoides using a stroke longer hydraulic this way,it reduces difficulty of the hydraulic cylinder’s produce. At the same time, it increases certain accumulators in the system, and limits absorption hydraulic pressure impact,which reduces the leather belt impulse and enhances the adhesive tape’s this issue ,the belt conveyer device whose tension force varied greatly is desiged to satisfy the re2 quirement s of the st ressed belt in varied length. It s tersion is greater in starting state ,and smaller in normal state moving. In the basis of working principle of automatic hydraulic tensioning device , st ructure composing , cont rol principle and function characteristics of the device were int roduced in this paper. It also expounded the design key of the cont rol system is to set pressure value and maxim drawing requirement of belt conveyer operating system. PLC is utilized to monitor the drive , brake and tension part of belt conveyer in real time and to realize autocontrol operating mode completely, constructing a control system with super reliability for equipment words：Belt-type conveyer； full automatic hydraulic tension station； automatic control； programmable control目 录1 概述 张紧装置的作用 张紧装置的类型及其介绍 液压张紧装置的基本介绍及其特点 液压张紧装置的特点 新型自动控制液压张紧装置的主要技术特点 液压传动的特点 带式输送机张紧装置的PLC控制系统介绍 PLC的介绍 带式输送机张紧装置的控制原理 62 带式输送机的工作原理 带式输送机的组成及工作原理 带式输送机的组成 带式输送机的工作原理 带式输送机的驱动原理——摩擦传动原理 单滚筒驱动情况 多滚筒驱动情况 163 带式输送机的选型设计计算 设计参数 带式输送机的机型选择 输送带的选择设计 选取带速 选择带宽 运行阻力的计算 输送带张力的计算 校核 张紧行程及张紧力的计算 张紧行程 张紧力 机型布置 布置原则 布置形式 滚筒的选择 电机、减速器的选型及有关驱动装置部件的选用 减速器的选型 有关驱动装置部件的选用 354 带式输送机的起动分析 带式输送机的起动曲线 起动时的动张力计算 起动时间 425 张紧装置选择方案 张紧装置的类型 方案比较与选择 446 张紧装置的设计 张紧装置组成 主要技术问题 张紧装置参数的确定 张紧力和张紧行程 启动加速度 起动时间 液压站及有关元件的设计与选用 液压油缸的设计 齿轮泵及电机 蓄能器 液压油箱的设计 电液比例溢流阀及其放大器 电磁换向阀、单向阀 机械结构设计 张紧车架 滑轮 注意事项与要求 张紧装置的振动 设备使用要求 587 电控系统 控制系统的硬件组成 PLC及扩展模块 测速传感器 压力变送器 PLC控制系统的硬件配置图 软件设计 思路及流程图 输入输出点地址分配 参数设定 带式输送机张紧装置PLC程序 68结 论 75参考文献 76英文原文 77中文译文 99致 谢 104可&联[系Q——Q：13....6.........后面输入....775..........接着输入12......5Q——Q空间里有所有内容。
建议看看下面的资料网，在这里想要谁给现写一篇，可能不会有，因为z这里没人会为了这个区花费一些时间去写的，所以根据我搜集的一些网站来看，希望对你有所帮助，用心去做，不管毕业论文还是平时作业吗，我相信你都可以做好的。毕业论文以及毕业设计的，推荐一个网 这个网站的论文都是以words的形式原封不动的打包上传的，网上搜索不到的，对毕业论文的写作有很大的参考价值，希望对你有所帮助。 论文写作建议看看下面的资料网，在这里想要谁给现写一篇，可能不会有，因为z这里没人会为了这个区花费一些时间去写的，所以根据我搜集的一些网站来看，希望对你有所帮助，用心去做，不管毕业论文还是平时作业吗，我相信你都可以做好的。写作资料也很多，下面给你一些范文资料网： 如果你不是校园网的话，请在下面的网站找： 百万范文网： 分类很细 栏目很多 毕业论文网： 引文数据库： 社科类论文： 经济类论文： 论文之家： 范文网： 如果你是校园网，那就恭喜你了，期刊网里面很多资料 中国知网： 龙源数据库： 万方数据库： 优秀论文杂志 论文资料网 法律图书馆 法学论文资料库 中国总经理网论文集 职业经理人论坛 财经学位论文下载中心 公开发表论文_深圳证券交易所 中国路桥资讯网论文资料中心 论文商务中心 ' 法律帝国： 学术论文 论文统计
关于医学影像毕业论文
在医院，X光、B超等等都属于医学影像技术，那么大家对医学影像了解有多少呢？在这里，我分享了给大家关于医学影像毕业论文，一起来学习吧！
摘 要 介绍医学影像发展的历程CT成像技术的优势和影像技术在数字化中的发展说明PACS系统基本原理与结构及采用这种体系结构的意义;指出影像学的发展对医学诊断过程具有极其重要的意义。
关键词 发展 成像技术 数字化
影像学发展概述及特点
影像学诊断是世纪医学诊断最重要发展最快的领域之一。CT的研制始于世纪6年代。1967年英国的工程师汉斯菲尔德开始了模式识别的研究工作。5年代X线透视和摄片是临床最常用的影像学诊断方法而今天由于X线CT技术的出现和应用使影像学诊断水平发生了飞跃从而极大地提高了临床诊断水平。即计算机体断层摄影(CT)即是利用计算机技术处理人体组织器官的切面显像。X线CT片提供给医生的信息量远远大于普通X线照片观察所得的信息。
CT成像技术的优势:CT与常规的影像学检查手段相比主要有以下四个方面的优点。
真正的断面图像:CT通过X线准直系统的准直可得到无层面外组织结构干扰的横断面图像。与常规X线体层摄影比较CT得到的横断面图像层厚准确图像清晰密度分辨率高无层面以外结构的干扰。
密度分辨率高:CT与常规影像学检查相比它的密度分辨率最高。其原因是:第一CT的X射线束透过物体到达检测器经过严格的准直散射线少;第二CT机采用了高灵敏度的、高效率的接收器;第三CT利用计算机软件对灰阶的控制可根据诊断需要随意调节适合人眼视觉的观察范围。一般CT的密度分辨率要比常规X线检查高约倍。
可作定量分析: CT能够准确地测量各组织的X射线吸收衰减值通过各种计算可作定量分析。
可利用计算机作各种图像处理:借助于计算机和某些图像处理软件可作病灶的形状和结构分析。采用螺旋扫描方式可获得高质量的三维图像和多平面的断面图像。
影像学的主要新技术
基于数字化的影像技术:随着信息时代的到来数字化、标准化、网络化作业已经进入医学影像界并以奔腾之势迅猛发展伴随着一些全新的`数字化影像技术陆续应用于临床。医学影像存档与通讯系统(PACS)和医学影像诊断报告系统应运而生并得到了快速发展使整个放射科发生着巨大变化提高了影像学科在临床医学中的地位和作用。
PACS的基本原理与结构:PACS是以计算机为中心由图像信息的获取、传输与存档和处理等部分组成。
图像信息的获取:CT、MRI、DSA、CR及ECT等数字化图像信息可直接输入PACS而众多的X线图像需经信号转换器转换成数字化图像信息才能输入。
图像信息的传输:在PACS中传输系统对数字化图像信息的输入检索和处理起着桥梁作用。
图像信息的储存与压缩:图像信息的储存可用磁带、磁盘、光盘和各种记忆卡片等。图像信息的压缩储存非常必要。因为一张X线照片的信息量很大相当于15多页字稿纸写满汉字的信息量而一个.8cm光盘也只能存储张X线照片的信息。压缩方法多用间值与哈佛曼符号压缩法影像信息压缩1/5～1/1仍可保持原有图像质量。
图像信息的处理:图像信息的处理由计算机中心完成。计算机的容量、处理速度和可接终端的数目决定着PACS的大小和整体功能。软件则关系到检索能力、编辑和图像再处理的功能。CT的计算机系统属于通用小型计算机为适合CT机的工作要求CT的计算机系统一般都具有运算速度快和存储量大这两个特点。
结 语
医学影像有着巨大的发展潜力如果每种影像模式都能成功抓住技术发展中的机遇和挑战那么这种潜力将会实现这将需要物理学家、工程师、数字家、信息学家和医生的共同努力。
毕业论文图片尺寸要求如下：
因学校和专业而异，但大多数学校对于毕业论文的图片要求都是较为严格的。通常，图片应该具有足够的分辨率和清晰度，以保证图片质量与整体论文风格一致。以下是详细解释：
1.学校要求
不同学校或专业对毕业论文图片的具体要求不尽相同。有一些学校规定了图片的像素和尺寸，通常要求图像分辨率不能低于300dpi，并限制了最大和最小宽度或高度值。
2.图片格式
通常来说，毕业论文要求使用JPG或PNG格式的图片。这两种格式的图片在保证高质量的情况下，可以控制文件大小和保持良好的压缩效果。尤其对于在线提交毕业论文的学校，要求的图片格式可能不同。
3.图片尺寸
毕业论文中的图片尺寸需要适应实际应用，即要对照教师或指导老师给的毕业论文要求，并参考大学期间的实验课、论文写作课等相关经验。
一些常用的图片尺寸包括：宽200像素，高150像素；宽400像素，高300像素；宽600像素，高450像素。另外，在插入大图时，应该经过压缩处理之后再放置到文中，以便控制图片大小和文件尺寸。
4.图片版式
毕业论文的图片还需要符合相关的版式要求。图片需要与论文正文相结合，同时也需要有明显的图例说明，不同来源的图片需要详细注明出处，以避免抄袭和知识产权问题。
附加知识
毕业论文是研究生和本科生毕业时必须完成的重要项目。它是学术研究和成果展示的体现，也是评价学生知识和能力的重要途径之一。
因此，无论是文献查阅、论文组织，还是图片处理、排版等方面，毕业论文都需要仔细地准备和编写。好的论文不仅是学生经过几年学习和实践积累的结晶，也是面对未来职业发展的有力证明。
关于内容：1、一般概括性内容：课题标题、答辩人、课题执行时间、课题指导教师、课题的归属、致谢等。2、课题研究内容：研究目的、方案设计（流程图）、运行过程、研究结果、创新性、应用价值、有关课题延续的新看法等。3、PPT要图文并茂，突出重点，让答辩老师明白哪些是自己独立完成的，页数不要太多，30页左右足够，不要出现太多文字，老师对文字和公式都不怎么感兴趣；4、凡是贴在PPT上的图和公式，要能够自圆其说，没有把握的坚决不要往上面贴。5、每页下面记得标页码，这样比较方便评委老师提问的时候review关于模板：1、可以去像素网选择一套合适的论文答辩PPT模板，不要用太华丽的企业商务模板，学术ppt最好低调简洁一些；2、推荐底色白底（黑字、红字和蓝字）、蓝底（白字或黄字）、黑底（白字和黄字），这三种配色方式可保证幻灯质量。我个人觉得学术ppt还是白底好；3、动手能力强的大牛可以自己做附和课题主题的模板，其实很简单，就是把喜欢的图在“幻灯片母版”模式下插入就行了。关于文字：1、首先就是：不要太多！！！图优于表，表优于文字，答辩的时候照着ppt念的人最逊了；2、字体大小最好选ppt默认的，标题用44号或40号，正文用32号，一般不要小于20号。标题推荐黑体，正文推荐宋体，如果一定要用少见字体，记得答辩的时候一起copy到答辩电脑上，不然会显示不出来；3、正文内的文字排列，一般一行字数在20～25个左右，不要超过6～7行。更不要超过10行。行与行之间、段与段之间要有一定的间距，标题之间的距离（段间距）要大于行间距；关于图片：1、图片在ppt里的位置最好统一，整个ppt里的版式安排不要超过3种。图片最好统一格式，一方面很精制，另一方面也显示出做学问的严谨态度。图片的外周，有时候加上阴影或外框，会有意想不到的效果；2、关于格式，tif格式主要用于印刷，它的高质量在ppt上体现不出来，照片选用jpg就可以了，示意图我推荐bmp格式，直接在windows画笔里按照需要的大小画，不要缩放，出来的都是矢量效果，比较pro，相关的箭头元素可以直接从word里copy过来；3、流程图，用viso画就可以了，这个地球人都知道；4、ppt里出现图片的动画方式最好简洁到2种以下，还是那句话，低调朴素为主；5、动手能力允许的话，学习一下photoshop里的基本操作，一些照片类的图片，在ps里做一下曲线和对比度的基本调整，质量会好很多。windos画笔+ps，基本可以搞定一切学术图片。关于提问环节：评委老师一般提问主要从以下几个方面：1.他本人的研究方向及其擅长的领域；2.可能来自课题的问题：是确实切合本研究涉及到的学术问题（包括选题意义、重要观点及概念、课题新意、课题细节、课题薄弱环节、建议可行性以及对自己所做工作的提问）；3.来自论文的问题：论文书写的规范性，数据来源，对论文提到的重要参考文献以及有争议的某些观察标准等；4.来自幻灯的问题：某些图片或图表，要求进一步解释；5.不大容易估计到的问题：和课题完全不相干的问题。似乎相干，但是答辩者根本未做过，也不是课题涉及的问题。答辩者没有做的，但是评委想到了的东西，答辩者进一步打算怎么做。提问环节很容易因为紧张被老师误导，如果老师指出你xx地方做错了，先冷静想一下，别立马就附和说啊我错了啊我没有考虑到。一般来说答辩老师提的问题，很少有你做课题这几年之中都没考虑到的。想好了再回答，不要顶撞老师，实在不会的问题，千万不要“蒙”，态度一定要谦虚，哪怕直接说“自己没有考虑到这点，请老师指正”。
修改图片大小。使用修图软件，对图片的大小，颜色和分辨率进行调整，一般来说论文中引用的图片需要调整为灰度。论文中图片的位置:插入文章的各类型图都应居中，并按排版需要调整大小，但图片宽度不应超过正文文本宽度。颜色:除特殊用途图片外，插图尽量不使用彩色图，应调为灰度。
毕业论文图片尺寸要求如下：
因学校和专业而异，但大多数学校对于毕业论文的图片要求都是较为严格的。通常，图片应该具有足够的分辨率和清晰度，以保证图片质量与整体论文风格一致。以下是详细解释：
1.学校要求
不同学校或专业对毕业论文图片的具体要求不尽相同。有一些学校规定了图片的像素和尺寸，通常要求图像分辨率不能低于300dpi，并限制了最大和最小宽度或高度值。
2.图片格式
通常来说，毕业论文要求使用JPG或PNG格式的图片。这两种格式的图片在保证高质量的情况下，可以控制文件大小和保持良好的压缩效果。尤其对于在线提交毕业论文的学校，要求的图片格式可能不同。
3.图片尺寸
毕业论文中的图片尺寸需要适应实际应用，即要对照教师或指导老师给的毕业论文要求，并参考大学期间的实验课、论文写作课等相关经验。
一些常用的图片尺寸包括：宽200像素，高150像素；宽400像素，高300像素；宽600像素，高450像素。另外，在插入大图时，应该经过压缩处理之后再放置到文中，以便控制图片大小和文件尺寸。
4.图片版式
毕业论文的图片还需要符合相关的版式要求。图片需要与论文正文相结合，同时也需要有明显的图例说明，不同来源的图片需要详细注明出处，以避免抄袭和知识产权问题。
附加知识
毕业论文是研究生和本科生毕业时必须完成的重要项目。它是学术研究和成果展示的体现，也是评价学生知识和能力的重要途径之一。
因此，无论是文献查阅、论文组织，还是图片处理、排版等方面，毕业论文都需要仔细地准备和编写。好的论文不仅是学生经过几年学习和实践积累的结晶，也是面对未来职业发展的有力证明。
里边是不是有很多图片。或者是单个图片非常大。要是纯文字这得多少万字。
不用非要在软件里找吧 你可以在别的地方找啊 比如说你在百度知道里直接找人问问 看有没有人有 这不更简单吗 在百度里直接搜不也很简单吗 都不难的 路径很多的
1.右键图片,设置图片格式--图片--压缩--应用于--文档中的所有图片---选项-压缩图片--确定
这是我从一篇文章下摘录下来的，请参考！ 模板：①白底：可以选择黑字，红字和蓝字，如果你觉得不够丰富，你可以改变局部的底色。②蓝底：深蓝更好一点，白字或黄字（浅黄和橘黄）,深蓝背景下不要选择暗红。是最普遍最保险，也是最简单的配色方案。③黑底：白字和黄字（橘黄比浅黄好）。这三种配色方式可以保证你的幻灯质量，如果你是第一次做，强力建议。 或许你觉得这样的幻灯太单调了，其实不然，你的幻灯不应该只有文字，你可以用各种模式图或流程图，使你的幻灯增加色彩，你也可以加一点小小的花边，或者在标题和正文之间加一条线，或者插入学校图标，都可以使你的幻灯不再单调 幻灯片制作大忌： 1. 忌讳大量文字与数字堆砌：幻灯最好采用标题式，讲解时按照标题发挥。将表格转换为统计图（如直方图）更为直观。每页幻灯文字不宜多于10行，正文字号不宜小于5号。 2. 忌讳铺天盖地不留余地：幻灯片应适当留出边缘，忌讳每页幻灯片内容都塞得满满地，看了头也大了。 3. 忌讳过于单调与过分花哨：一个人穿上一身的朴素衣服显得单调，浑身上下都穿上花衣服也未必好看。幻灯的生动体现在背景与文字的颜色搭配、图片与动画的适当应用等诸多方面，关键是两个字－－“和谐” 幻灯制作必杀技巧： 在制作幻灯前，下列技巧你必须掌握： 1. 图片压缩与编辑：幻灯片中经常会用到位图和插图，扫描和部分下载的bmp图片太大，插入幻灯后将令幻灯立刻“肥胖”，你必须学会压缩为jpeg等格式，压缩和裁减图片使用acdsee等就可以搞定；当然，PowerPoint 2002可以在这方面为你效劳，在创建幻灯的过程中，用户可以随时通过调用"图像"工具条对一个或几个位图图片进行压缩，依次选择"视图">"工具?quot;>"图片"，点击工具条上的"压缩图片"按钮即可。 另外，很多网上下载的图片往往需要复杂修改，你当然必须掌握photoshop等软件；作为高手，往往还需要自己制作部分重要的矢量图，需要掌握一种相关软件。 2. 统计图表的制作：一般的图表在powpoint里面就可以搞定，需要标记标准差的直方图则需要在excel里进行编辑，复杂的统计图甚至需要在统计软件里搞定。 3. 插入多媒体与动画：如果你像为你的幻灯添加动感，你还必须掌握插入多媒体（如avi）和动画（如swf）的方法以及设置播放的技巧，如果你还不会，赶紧在网上看看教程或请教别人吧。 4. 其他文字与动画技巧：学会制作不断闪烁的文字或图案，定义动画，定义幻灯片切换方式等可以使你的幻灯更加生动。 www,