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中国联通电信智能卡SWP卡测试规范v2.0

中国联通电信智能卡SWP卡测试规范v2.0

中国联通公司发布目次目次 (I)前言...................................................................................................................................... V III 1范围 (1)2规范性引用文件 (1)3术语、定义和缩略语 (1)3.1术语 (1)3.2符号 (2)3.3缩略语 (3)3.4编码规则 (3)4测试环境 (4)4.1应用测试环境 (4)4.1.1测试环境 (4)4.2测试设备 (4)4.3初始条件 (4)4.4SWP协议测试环境 (5)4.4.1测试设备 (5)4.4.2测试条件 (5)4.4.2.1测量和环境参数的范围 (5)4.4.2.2温度 (5)4.4.2.3TS 102 221接口触点(CLK, RST, I/O)和触点Vcc (6)4.4.2.4TS 102 613接口触点(SWIO) (6)4.4.2.5UICC接口的状态 (7)4.4.2.6LLC层的特性 (7)4.4.2.7触点Vcc (7)4.4.3测试执行 (7)4.5HCI协议测试环境 (7)4.5.1测试设备 (7)4.5.2测试条件 (8)4.5.2.1一般情况 (8)4.5.2.2UICC接口的状态 (8)4.5.3测试执行 (8)4.5.3.1参数种类 (8)4.5.3.2执行要求 (8)4.6HCI API测试 (8)4.6.1测试终端 (9)4.6.2测试卡片 (9)4.6.3读卡器 (9)4.6.4测试应用 (9)5应用测试 (11)6SWP协议测试 (11)6.1系统结构 (11)6.1.1配置 (11)6.1.1.1符合条件 (11)6.1.1.2ATR的全局接口字节 (11)6.1.1.3与TS 102 221接口并存,在UICC接收数据时激活SWP接口 (11)6.1.1.4与TS 102 221接口并存,当UICC发送数据时激活SWP接口 (12)6.1.2与其他接口并存 (12)6.1.2.1符合条件 (12)6.1.2.2与TS 102 221接口并存,TS 102 221时钟停止 (13)6.1.2.3与TS 102 221接口并存,TS 102 221复位 (13)6.1.2.4与TS 102 221接口并存,UICC接收数据时使SWP接口失效 (14)6.1.2.5与TS 102 221接口并存,UICC发送数据时使SWP接口失效 (14)6.1.2.6与TS 102 221接口并存,UICC接收数据时复位SWP (15)6.1.2.7与TS 102 221接口并存,UICC发送数据时复位SWP (15)6.2物理特性 (16)6.2.1卡工作运行的温度范围 (16)6.2.1.1一致性要求 (16)6.2.2触点 (16)6.2.2.1一致性要求 (16)6.2.3接口激活 (16)6.2.3.1一致性要求 (16)6.2.3.2在终端不支持SWP时UICC的行为 (24)6.3电气特性 (25)6.3.1支持电压等级 (25)6.3.1.1一致性要求 (25)6.3.1.2TS102 221电压等级B和C (25)6.3.2Vcc(C1)低电压模式定义 (25)6.3.2.1一致性要求 (25)6.3.2.2低电压模式操作 (25)6.3.3信号S1 (26)6.3.3.1一致性要求 (26)6.3.3.2电压等级B中的S1信号 (26)6.3.3.3电压等级C中的S1信号 (27)6.3.3.4低电压模式下的S1信号 (28)6.3.4信号S2 (29)6.3.4.1一致性要求 (29)6.3.4.2电压等级B下的信号S2 (29)6.3.4.3电压等级C中的S2信号 (30)6.3.4.4低电压模式下的S2信号 (30)6.4物理传输层 (31)6.4.1S1 Bit 编码和抽样时间 (31)6.4.1.1一致性要求 (31)6.4.1.2变化时序,默认比特时间的通讯 (32)6.4.1.3变化时序,延展比特时间的通讯 (32)6.4.1.4S1上升和下降时间 (33)6.4.1.5C6输入电容测量 (34)6.4.2S2转换测量 (35)6.4.2.1一致性要求 (35)6.4.2.2S2转换测量 (35)6.4.3SWP接口状态管理 (35)6.4.3.1一致性要求 (35)6.4.3.2UICC管理SWP接口状态 (36)6.4.4供电模式状态/转换和省电模式 (36)6.4.4.1一致性要求 (36)6.4.4.2低电模式下的供电状态(ACT_POWER_MODE) (36)6.4.4.3低电模式下的电压模式(非ACT) (37)6.4.4.4全供电模式下的供电状态不包含TS102.221 (37)6.4.4.5省电模式包括TS102.221接口–先重启TS102.221接口 (38)6.4.4.6省电模式包括TS102.221 –先重启TS102.613接口 (38)6.4.4.7全供电模式供电状态,包括TS102.221 (38)6.5数据链路层 (39)6.5.1MAC层 (39)6.5.1.1比特顺序 (39)6.5.1.2一致性要求 (39)6.5.1.3默认状态下的帧交换 (39)6.5.1.4结构 (39)6.5.1.5一致性要求 (39)6.5.1.6错误格式帧的解释-ACT LLC (40)6.5.1.7比特填充 (42)6.5.1.8错误检测 (42)6.5.2支持的LLC层 (43)6.5.2.1支持的LLC层 (43)6.5.2.2LLC层的交互 (43)6.5.3ACT LLC的定义 (47)6.5.3.1ACT LLC的定义 (47)6.6SHDLC LLC定义 (49)6.6.1SHDLC 概述 (49)6.6.1.1一致性要求 (49)6.6.1.2非正常数据到下一层的传输处理 (49)6.6.1.3出错管理,EUT发送I-帧 (50)6.6.1.4出错管理 (50)6.6.1.5修改滑动窗口和端点能力 (50)6.6.1.6UA帧有效负载 (51)6.6.1.7无有效负载UA帧-ES复位 (51)6.6.1.8无有效负载UA帧-EUT复位 (51)6.6.1.9SHDLC上下文 (51)6.6.1.10初始复位状态 (51)6.6.1.11连接复位时初始状态-由EUT复位 (52)6.6.1.12连接复位时初始状态-由ES复位 (52)6.6.1.13SHDLC帧序列 (52)6.6.1.14数据流 (58)6.6.1.15拒收(回退N) (60)6.6.1.16最后一帧丢失 (62)6.6.1.17接收未准备就绪 (63)6.6.1.18选择性拒绝 (64)6.7CLT LLC定义 (66)6.7.1CLT 帧格式 (67)6.7.1.1一致性要求 (67)6.7.1.2CLT PAYLOAD以A型排列结构的字符填充 (67)6.7.2CLT命令配置 (67)6.7.2.1一致性要求 (67)6.7.2.2CLT 指令, ISO/IEC 14443 A型 (68)6.7.2.3CLT 指令, ISO/IEC 18092 (69)6.7.3CLT 帧编译 (69)6.7.3.1ADMIN_FIELD的处理:CL_PROTO_INF(A) (69)7HCP测试 (70)7.1HCP消息结构 (70)7.1.1一致性要求 (70)7.1.2管道未打开时, 该管道上命令和事件的测试. (71)7.2指令 (72)7.2.1通用命令 (72)7.2.1.1ANY_SET_PARAMETER (72)7.2.1.2ANY_SET_PARAMETER接收-无效结构 (72)7.2.1.3ANY_SET_PARAMETER接收-RO注册参数 (73)7.2.1.4ANY_GET_PARAMETER (73)7.2.1.5ANY_SET_PARAMETER接收-无效结构 (73)7.2.1.6ANY_GET_PARAMETER接收-WO注册参数 (74)7.2.1.7ANY_OPEN_PIPE (74)7.2.1.8ANY_OPEN_PIPE接收 (74)7.2.1.9ANY_OPEN_PIPE传输 (76)7.2.1.10ANY_CLOSE_PIPE (76)7.2.1.11ANY_CLOSE_PIPE接收 (76)7.2.1.12ANY_CLOSE_PIPE传输 (77)7.3响应 (78)7.3.1一致性要求 (78)7.3.2对未知命令的响应 (78)7.3.3对乱序的,以前由主机控制器发出的命令的响应 (78)7.3.4对乱序的,以前由主机发出的命令的响应 (79)7.4事件 (79)7.4.1一致性要求 (79)7.4.2对未知事件的接收 (79)7.5网关和相关条款 (80)7.5.1网关 (80)7.5.1.1一致性要求 (80)7.5.1.2链接管理网关支持的命令和事件 (80)7.5.1.3除链接管理网关外其他管理网关支持的命令和事件 (80)7.5.2管理网关 (81)7.5.2.1主机控制器管理网关 (81)7.5.2.2主机控制器链路管理网关 (82)7.5.2.3主机链路管理网关 (83)7.5.2.4身份管理网关本地注册表 (83)7.6HCI过程 (85)7.6.1Pipe管理 (85)7.6.1.1Pipe创建 (85)7.6.1.2Pipe删除 (87)7.6.1.3清除全部Pipes (88)7.6.2会话初始化 (91)7.6.2.1一致性要求 (91)7.6.2.2SESSION_IDENTITY 未改变 (92)7.6.2.3SESSION_IDENTITY 改变 (92)7.6.3回环测试 (93)7.6.3.1一致性要求 (93)7.6.3.2Host控制器Pipe创建 (93)7.6.3.3另一Host控制器Pipe创建 (93)7.6.3.4EVT_POST_DATA过程 (94)7.7HCI API测试 (94)7.7.1基础包测试 (94)7.7.1.1HCIDevice测试 (94)7.7.1.2HCIService测试 (97)7.7.1.3HCIMessage测试 (102)7.7.1.4HCIListener测试 (107)7.7.1.5HCIException测试 (107)7.7.2卡模拟模式 (109)7.7.2.1CardEmulationMessage测试 (109)7.7.2.2CardEmulationService测试 (111)7.7.3连接模式 (112)7.7.3.1Connectivity Service测试 (112)7.7.4读卡器模式 (115)7.7.4.1ReaderService测试 (115)7.7.4.2ReaderMessage测试 (115)8GP测试 (118)9JAVA CARD API测试 (118)10基础引擎模块API测试 (118)11空间检测测试 (118)11.1应用下载空间测试 (118)11.2RTR空间测试 (118)11.3DTR空间检测 (119)12非接触性能测试 (120)12.1刷卡距离测试 (120)12.2脱机消费响应时间测试 (121)12.3刷卡成功率测试 (121)12.4通讯速率测试 (122)13OTA测试 (122)13.1OTA引擎测试 (122)13.2菜单翻页测试 (123)前言近场通信(NFC)是基于RFID技术发展起来的一种近距离高频无线通信技术,工作在13.56MHz 频段,可在短距离内实现电子身份识别或者数据传输功能。

p2p的功能

p2p的功能

p2p的功能P2P(点对点)网络是一种基于对等连接的网络系统,其中所有计算机都充当客户端和服务器的角色,共享和分发资源。

与传统的中心化网络相比,P2P网络拥有独特的功能和优势。

下面将介绍P2P网络的功能。

首先,P2P网络具有分布式的特点。

在传统的中心化网络中,中央服务器负责管理和分发资源,当服务器宕机或故障时,整个网络会陷入瘫痪。

而在P2P网络中,每个节点都存储一部分资源,当一个节点离线时,其他节点仍然可以继续共享和分发资源,网络的稳定性更高。

其次,P2P网络具有高效的资源共享和分发功能。

在P2P网络中,每个节点都可以共享和分发自己的资源,而不受中心服务器的限制。

这使得用户能够更快地获取所需的资源,例如文件、音乐、视频等。

同时,P2P网络也可以利用节点之间的带宽和存储空间,提高资源的可用性和下载速度。

另外,P2P网络具有匿名性和安全性。

在传统的中心化网络中,用户需要向中央服务器提供个人信息并受到监控。

而在P2P网络中,用户可以通过直接连接其他节点来共享和分发资源,无需向中央服务器提供个人信息,从而保护个人隐私和安全。

此外,P2P网络还具有弹性和扩展性。

在传统的中心化网络中,当用户数量增加时,中央服务器可能无法承受大量的请求,导致网络拥堵或崩溃。

而在P2P网络中,每个节点都充当服务器的角色,当节点数量增加时,网络的处理能力和吞吐量也会增加,从而使得网络具有更好的扩展性和适应性。

最后,P2P网络也具有自修复的功能。

在传统的中心化网络中,当服务器发生故障时,需要人工修复或更换服务器。

而在P2P网络中,每个节点都可以备份和共享资源,当一个节点离线或发生故障时,其他节点可以自动接替其角色,继续共享和分发资源,从而使网络具有自我修复的能力。

总之,P2P网络是一种具有各种功能和优势的网络系统。

它具有分布式的特点,能够高效地共享和分发资源,并保护用户的隐私和安全。

同时,P2P网络还具有弹性和扩展性,以及自修复的能力。

无刷电动调速器用户手册说明书

无刷电动调速器用户手册说明书

0103Specifications04User Guide05ESC Programming06Programmable Items07Data CheckingProgrammable Item List of Platinum 60A V4 ESC. (“*” in the form below indicate factory defaults. )USER MANUALHV 130A V4 / HV 130A OPTO V4Brushless Electronic Speed Controller1. Flight Mode:1.1 In “Fixed-wing” mode, the motor will start up when the throttle amount reaches 5% or above. There is no soft start-up, the motor responds to the throttle increase rapidly.1.2 In “Helicopter (Linear Throttle)” mode, the motor will start up when the throttle amount reaches 5% and it will start up in a soft way with the throttle (from 0 to 100%) acceleration time is fixed to 3.5 seconds. It will accelerate to the RPM corresponds to the specific throttle amount at the fixed rate.1.3 In “Helicopter (Elf Governor)” mode, the motor will start up when the throttle amount reaches 40% or above. And it will complete the speed standardization and enter the speed-governing operation in the preset start-up time (4~25s). In this mode, the motor will standardize its speed every time it starts up. Due to different discharge rates/capabilities of different batteries, the RPM you standardize each time may be a little different. In consequence, at the same throttle amount, the RPM may be a bit different when using different batteries, but this won’t affect the speed-governing effect.1.4 In “Helicopter (Store Governor)” mode, the motor will start up when the throttle amount reaches 40% or above. It will also start up in a very soft way. And it will also complete the speed standardization and enter the speed-governing operation in the preset start-up time. In this mode, the motor will only standardize its speed the first time when it starts up. When performing RPM standardization for the first time, we recommend using a fully-charged battery with good discharge capability. After the RPM standardization, change another battery to fly your aircraft. At the same throttle amount, the RPM should be the same as the RPM of the first flight. For consistent control feel, we recommend using this mode. About RPM Standardization & OthersI. The motor will enter the soft start-up when user switches the throttle amount from 0 to 40% or above (50%throttle is recommended). The pitch of main blades should be 0 degree during the• High performance microprocessor for excellent motor speed-governing and super soft start-up.• Microprocessor powered by independent DC regulator has better anti-interference performance, which greatly reduces the risk of losing control.• DEO (Driving Efficiency Optimization) Technology adopted greatly improves throttle response & driving efficiency, reduces ESC temperature.• New switch-mode BEC with adjustable output voltage ranges from 5V to 8V and continuous/peak current of 10A/25A.• BEC is separated from other circuits of the ESC, it will keep its normal output when the MOSFET board of the ESC is burnt. • Multiple flight modes: Fixed-wing, Helicopter (Linear Throttle), Helicopter (Elf Governor),Helicopter (Store Governor).• New governor program with adjustable governor parameter P/I brings excellent speed-governing effect, guarantees the stability of the propeller’s revs when the load changes dramatically. • Data logging records the standardized RPM, minimum voltage and maximum temperature of the flight.• "Restart in auto rotation" can manually interrupt the auto rotation and quickly restart the motor to avoid crashes caused by incorrect operations. • Independent output port for RPM (that is: motor speed) signals.• Separate programming port for ESC programming or parameter setting.• WIFI module (sold separately) for programming the ESC wirelessly with your smart phone (IOS or Android).• Online data checking, ESC programming, firmware upgrade (Multifunction LCD program box or WIFI Express is needed) supported.• Multiple protections like start-up protection, ESC thermal protection, capacitor thermal protection, over-current protection, overload protection, and throttle signal loss protection.Model Applications Input Voltage Cont./Peak Current (10s)BEC OutputThrottle Signal/BEC Output/RPM Signal Transmission WiresSize/WeightSeparate Programming PortPlatinum HV 130A V4White Throttle Signal Wire/Red & Black BEC Output Wires/Yellow RPM Signal Transmission WireFor connecting Multifunction LCD Program Box/WIFI module or fanSwitch-mode, 5V-8V Adjustable (Step:0.1V), 10A/25A Cont./Peak101x45.5x27mm / 168.5gProgrammingConnect the LCD program box and a battery to your ESC as shown above.successfully connected to your ESC.relates to the ESC.main blades =R ÷ Motor Poles ÷ 2 ÷ Gear Ratio × Throttle Amount (%).channel on the VBAR system. About which channel you should plug it in, it depends on your receiver and flybarless system. The White wire is for transmitting Program Your ESC with a WIFI Express: For detailed information, please refer to the user manual of WIFI Express.The ESC will record the standardized RPM, minimum voltage, maximum current and maximum temperatures of the flight but won’t save these data, so you need to keep the ESC on if you want to check theinformation of the flight.08Normal Start-up ProcessTurn on the transmitter, and then move the throttle stick to the bottom position.After connected to a battery, the ESC will emit “♪123” indicating it’s normally powered on.The motor will emit several beeps to indicate the number of LiPo cells.The motor emits a long beep indicating the ESC is ready to go.09Explanations for Warning Tones1. Input voltage is abnormal:The ESC will measure the input voltage the moment when it’s powered on. The motor will keep beeping “BB, BB, BB” (the interval between two BBs is 1 second) when the input voltage is beyond the normal range. The warning tone won’t stop until the voltage turns normal. 2. Throttle signal loss protection is activated:The motor will beep “B-, B-, B-” (the interval between two B-s is 2 seconds) when the ESC doesn’t detect any throttle signal. 3. Throttle stick is not at the bottom position:The motor will beep “B-B-B-B-B-” when the throttle stick is not moved to the bottom position.4. Throttle range is to narrow:The motor will beep “B-B-B-B-B-” when the throttle range you set is too narrow (when designing this ESC, it requires that the entire throttle range you set cannot be less than 50% of the whole throttle range available on the transmitter.) The warning tone indicates the throttle range you set is void and you need to set it again.10Explanations for Multiple Protections11Different Troubles & Status LEDs1. Start-up Protection:The ESC will monitor the motor speed during the start-up process. When the speed stops increasing or the speed increase is not stable, the ESC will take it as a start-up failure. At that time, if the throttle amount is less than 15%, the ESC will automatically try to restart up; if it is larger than 15%, you need to move the throttle stick to back the bottom position and then restart up the ESC. (Possible causes of this problem: poor connection/ disconnection between the ESC and motor wires, propellers are blocked, etc.)2. ESC Thermal Protection:The ESC will gradually reduce the output but won’t cut it off completely when the ESC temperature goes above 110℃. For ensuring the motor can still get some power and won’t cause crashes, so the maximum reduction is about 50% of the full power. The ESC will gradually resume its maximum power after the temperature lowers down. In addition, the ESC temperature cannot exceed 70℃ when it’s powered on. Otherwise, it cannot be started up. (Here we are describing the ESC’s reaction in soft cutoff mode, while if in hard cutoff mode; it will immediately cut off the power.) 3. Capacitor Thermal Protection:The ESC will activate this protection when the operating temperature of capacitors goes over 130℃. It protects capacitors in the same way as the ESC thermal protection does to the ESC .4. Throttle Signal Loss Protection:When the ESC detects loss of signal for over 0.25 second, it will cut off the output immediately to avoid an even greater loss which may be caused by the continuous high-speed rotation of propellers or rotor blades. The ESC will resume the corresponding output after normal signals are received. 5. Overload Protection:The ESC will cut off the power/output or automatically restart itself when the load suddenly increases to a very high value. (Possible cause to sudden load increase is that propellers are blocked.)6. Over-current Protection:The ESC will cut off the power when the current gets close to the short circuit current (of 400A). This protection may be activated by the burnt motor or some others.soft start-up process, the RPM standardization completes when the soft start-up ends, and the ESC makes the motor enter the speed-governing state. In “Helicopter (Store Governor)” mode, if user wants to re-standardize the speed, he needs to set the flight mode to “Helicopter (Elf Governor)” and save this mode first, and then reset the flight mode back to “Helicopter (Store Governor)”, then the ESC will re-standardize the motor speed when the motor rotates for the first time after the ESC is powered off and then on again.II. For ensuring the speed-governing effect, we recommend setting the throttle amount to 85% or below in both speed-governing modes (Helicopter (Store Governor) & Helicopter (Elf Governor)), so there will besufficient compensating room to maintain the consistency of the RPM. We recommend replacing the motor or adjusting the gear ratio if the expected RPM still cannot be reached when the throttle amount exceeds 85%. (Note: You need to re-standardize the RPM after replacing the motor, blades, body frame or adjusting the gear ratio.)III. In “Helicopter (Store Governor)” mode, if you fly your aircraft with another pack that has poor discharge capability after the RPM standardization (with a pack which has good discharge capability), the pack has poor discharge capability will get damaged.IV. In “Helicopter (Store Governor)” mode, different battery packs can bring the same stable RPM only if they have the same cell count. This won’t change even when you change the battery pack. However, battery packs with different cell count don’t have the same effect. For instance, in “Helicopter (Store Governor)” mode, you can not use a 4S to calibrate the motor RPM and then use a 6S to drive the motor, hoping it can run at the same RPM.V. User can decide the control feel via adjusting Governor Parameter P/I. In “Helicopter (Store Governor) or Helicopter (Elf Governor)” mode, connect your ESC to a smart phone or PC, then you can check the throttle vs speed chart.2. LiPo Cells: The ESC will automatically calculate the number of LiPo cells you have plugged in as per the “3.7V/Cell” rule if “Auto Calc.” is selected. Or user can set this item manually. 3. Voltage Cutoff Type:The ESC will gradually reduce the output to 50% of the full power in 3 seconds after the voltage cutoff protection is activated, if soft mode is selected . It will immediately cut off all the output when hard mode is selected. 4. Cutoff Voltage: 2.8V-3.8V (custom), 3.0V (default).5. BEC Voltage: 5-8V (adjustable), 0.1V (step), 6V (default).6. Start-up Time: 4-25s (adjustable), 1s (step), 15s (default). (Note: It only functions in Helicopter (Store Governor) and Helicopter (Elf Governor))7. Governor Parameter P: Control the ESC maintaining the stability of the current motor speed.8. Governor Parameter I: Control the dynamic response. To be specific, control the supplement extent when the actual motor speed is below expectation. If you choose a very big value, then the supplement may be too much. If select a very small value, then the supplement may not sufficient.9. Auto Restart Time:the ESC will cut off its output when the throttle amount is between 25% and 40%. If you increase the throttle amount to above 40% within preset time period (0-90s), the motor will rapidly start up and accelerate to the speed (in the programmed Restart Acceleration Time) corresponds to the specific throttle amount, complete the shutdown and restart up . If you move the throttle stick to over 40% beyond the preset time period, the ESC will enter the soft start-up process. (Note: This function won’t effect unless the throttle amount is over 25% and it only effects in “Helicopter (Store Governor) and Helicopter (Elf Governor)” mode.)10. Restart Acceleration Time:1-3s (adjustable), 0.5s (step), 1.5s (default). This item controls the time the motor will cost to restart and accelerate to the full speed. (This function only effects in “Helicopter Governor Elf/Store” mode) 11. Brake Type:11.1 Proportional Brake: when the throttle range on the transmitter is between 20% and 100%, the corresponding ESC throttle output is between 0% and 100%.When the throttle range on the transmitter is between 20% and 0%, the corresponding brake force is between 0 and 100%.11.2 Reverse: after selecting this option, the RPM signal wire will turn into a reverse signal wire (the signal range is in line with the throttle range). After setting a channel on the transmitter, when the reverse signal length is above 20% signal length, the Reverse mode will be activated. The reverse signal length must be below 20% signal length when the ESC is powered on for the first time. When the reverse signal length is below 20% signal length, 0-100%throttle corresponds to “CW”; when the reverse signal length is above 20% signal length, the motor will stop spinning CW (and then spin CCW); at this time, 0-100% throttle corresponds to “CCW”. Any signal loss will activate the throttle signal loss protection, no matter it happens to the RPM signal wire or the throttle signal cable during the flight.12. Brake Force: 0-100% (adjustable), 1% (step), 0 (default). (Note: this function only effects in “Normal Brake” mode.)13. Timing: 0-30° (adjustable), 1° (step), 15° (default).14. Motor Rotation: CW/CCW. User can adjust this item via a multifunction LCD program box.15. DEO (Freewheel): User can decide this function “Enabled” or “Disabled” in “Fixed Wing” mode or in “Helicopter (Linear Throttle)” mode. This item has been preset to “Enabled” and cannot be adjusted in “Helicopter (Store Governor) and Helicopter (Elf Governor)” mode. This function can brings better throttle linearity.During the normal operation, the Blue LED on the ESC will turn solid after the start-up completes. The Red LED will come on at full throttle and dies out at partial throttle.。

光纤通信技术课后部分习题答案

光纤通信技术课后部分习题答案

4.51 Calculate the pulse spreading caused by chromatic dispersion for BF04431-02 multimode grade-index fiber from SpecTran, (See Figure 3.20) operating at 1300 nm. Assume = 70 nm. S: Taking 0 = 1342.5 nm, S0 = 0.097 ps
t GI
L NA 4 L NA 4 32cN 13 32cn13
1 BR 4t
where N1 core group index of refraction
Hence, BRGI
8cn13 8 3 10 8 1.486 3 4.92 10 9 bit / s 4.92Gbit / s L NA4 1 10 3 0.200 4
P 4.34
2
4
t BR
2
2
PD=2.17 dB ( realizable!)
4.56 What is the bit-rate length limitation caused by chromatic disperson for the Spectran fiber referred to in Problem 4.51? S: (BR x L)max = 1 / [4 D()] 1 4( 2 ) D
4.55 What is meant by the term dispersion power penalty? Calculate the disperson power penalty for the pulse spread obtained in Problem 4.51. The BR is 2.5 Gbit/s. S: The amount of transmitting power required for compensating the increase bit error rate (BER) cause by attenuation is called dispersion power penalty. In Problem 4.51, ttotal = tmat = 18 ns (if fiber length is 100 km) PD(dB) = -10 log10 {exp[-(1/4 ) (ttotal)2 (BR)2]} = -10 log10 {exp[-1/4 x (18 x 10-9)2 ( x 2.5 x 109)2]} = 2.17 x 104 dB, enough to burn any type of fiber, impossible. if the fiber length is 1 km:

操作系统试题库(经典版)

操作系统试题库(经典版)

操作系统试题库一, 选择题第一部分:操作系统概述1.在计算机系统中,操作系统是( B ).A. 一般应用软件B.核心系统软件C.用户应用软件D.系统支撑软件2.( D )不是基本的操作系统.A,批处理操作系统B,分时操作系统C,实时操作系统D,网络操作系统3.(C )不是分时系统的基本特征:A,同时性B,独立性C,实时性D,交互性4.关于操作系统的叙述(D)是不正确的.A."管理资源的程序"B."管理用户程序执行的程序"C."能使系统资源提高效率的程序"D."能方便用户编程的程序"5.操作系统的发展过程是(A )A.设备驱动程序组成的原始操作系统,管理程序,操作系统B.原始操作系统,操作系统,管理程序C.管理程序,原始操作系统,操作系统D.管理程序,操作系统,原始操作系统6.设计批处理多道系统时,首先要考虑的是( B)A.灵活性和可适应性B.系统效率和吞吐量C.交互性和响应时间D.实时性和可靠性7.操作系统是一种(B ).A, 应用软件B, 系统软件C, 通用软件D, 工具软件8.计算机系统的组成包括(B ).A,程序和数据B, 计算机硬件和计算机软件C,处理器和内存D,处理器,存储器和外围设备9.下面关于计算机软件的描述正确的是(B ).A,它是系统赖以工作的实体B,它是指计算机的程序与文档C,位于计算机系统的最外层D,分为系统软件和支撑软件两大类10.财务软件是一种(C).A,系统软件B,接口软件C,应用软件D,用户软件11.世界上第一个操作系统是(B).A,分时系统B,单道批处理系统C,多道批处理系统D,实时系统12.批处理操作系统提高了计算机的工作效率,但(B ).A,系统吞吐量小B,在作业执行时用户不能直接干预C,系统资源利用率不高D,不具备并行性13.允许多个用户以交互使用计算机的操作系统是(A).A,分时系统B,单道批处理系统C,多道批处理系统D,实时系统14.下面关于操作系统的叙述正确的是(A ). A,批处理作业必须具有作业控制信息B,分时系统不一定都具有人机交互功能C,从响应时间的角度看,实时系统与分时系统差不多D,由于采用了分时技术,用户可以独占计算机的资源15.操作系统是一组(C ).A,文件管理程序B,中断处理程序C,资源管理程序D,设备管理程序16.现代操作系统的两个基本特征是(C)和资源共享.A,多道程序设计B, 中断处理C,程序的并发执行D, 实现分时与实时处理17.(D)不是操作系统关心的主要问题. A, 管理计算机裸机B, 设计,提供用户程序与计算机硬件系统的界面C, 管理计算机系统资源D, 高级程序设计语言的编译器18.引入多道程序的目的是(D ).A,为了充分利用主存储器B,增强系统的交互能力C,提高实时响应速度D,充分利用CPU,减少CPU的等待时间19.在多道程序设计的计算机系统中,CPU(C ).A,只能被一个程序占用B,可以被多个程序同时占用C,可以被多个程序交替占用D,以上都不对20.多道程序设计是指(B ).A,有多个程序同时进入CPU运行B,有多个程序同时进入主存并行运行C,程序段执行不是顺序的D,同一个程序可以对应多个不同的进程21.从总体上说,采用多道程序设计技术可以( )单位时间的算题量,但对每一个算题,从算题开始到全部完成所需的时间比单道执行所需的时间可能要(B).A,增加,减少B,增加,延长C,减少,延长D,减少,减少22.(A)没有多道程序设计的特点.A,DOS B,UNIX C,WINDOWS D,OS/223.下列四个操作系统中,是分时系统的为(C ).A,MS-DOS B,WINDOWS 98C,UNIX D,OS/2系统24.在分时系统中,时间片一定,( B),响应时间越长.A,内存越多B,用户数越多C,后备队列D,用户数越少25.批处理系统的主要缺点是(B ).A,CPU的利用率不高B,失去了交互性C,不具备并行性D,以上都不是26.在下列性质中,哪一个不是分时系统的特征.( C )A, 交互性B, 多路性C, 成批性D, 独占性27.实时操作系统追求的目标是( C). A,高吞吐率B,充分利用内存C, 快速响应D, 减少系统开销28.以下(C)项功能不是操作系统具备的主要功能.A,内存管理B,中断处理C,文档编辑D,CPU调度29.操作系统程序结构的主要特点是(C). A, 一个程序模块B,分层结构C, 层次模块化D,子程序结构30.操作系统负责为方便用户管理计算机系统的(C ).A, 程序B, 文档资料C, 资源D, 进程31.计算机在接受用户请求后处理数据以与在数据处理结束时,将结果送到终端显示器.例如,导弹控制系统应选择安装(C )A,批处理操作系统B,分时操作系统C,实时操作系统D,网络操作系统32.操作系统的基本职能是(A).A.控制和管理系统内各种资源,有效地组织多道程序的运行B.提供用户界面,方便用户使用C.提供方便的可视化编辑程序D.提供功能强大的网络管理工具33.分布式操作系统与网络操作系统本质上的不同在于(D ).A.实现各台计算机之间的通信B.共享网络中的资源C.满足较大规模的应用D.系统中若干台计算机相互协作完成同一任务34.Linux操作系统是著名的(B )。

P2P应用基础知识

P2P应用基础知识
额,比万维网应用所占的比例大得多。
1 具有集中目录服务器的 P2P 工作方式
Napster 最早使用 P2P 技术,提供免费下载 MP3 音乐。 Napster 将所有音乐文件的索引信息都集中存放在 Napster 目录
服务器中。 使用者只要查找目录服务器,就可知道应从何处下载所要的MP3文
件。 用户要及时向 Napster 的目录服务器报告自己存有的音乐文件。 Napster 的文件传输是分散的,文件的定位则是集中的。
29
30
31
0
1
2
3 4
N4
27 26
5 6
25
7 N7
24
8
23
9 K8
22 21 20
10
11 N10
12
N20
19 18
17
16
15
13 14
K12 N13
(b) N13加入,N26退出
通过指针表加速 Chord 表查找
为了加速查找,在 Chord 环上可以增加 一些指针表(finger table),它又称为路 由表或查找器表。
对于结点 N4, 第 1
列第 i 行计算(N4
+ 2i – 1),得出后继 结点。
图例:
NID KID
N30
K31 K2
K29
29 30 31 0
12 3
N4
28
4
N26
27 26
5 6
K23 25
7 N7
N20 的指针表
N20 + 1 N26 N20 + 2 N26 N20 + 4 N26 N20 + 8 N30 N20 + 16 N4

P2P原理简介

P2P原理简介

P2P(点对点)下载技术原理简介作者:Nacy各位想必都用过BT下载吧?现在的BT下载可以说是继局域网、ftp、http之后最广泛使用的文件分享和传播途径,可以说已经融入了广大网民的生活中。

bt,全称BitTorrent,是一种P2P下载方式。

常见的P2P除了bt就是emule为什么P2P可以在如此短的时间内风靡世界呢?这是为什么呢???这里就要从它的原理说起,在介绍P2P的原理之前,有必要先解释下传统的http下载。

传统的http下载是从服务器(sever)上直接复制数据给客户端(PC),这种传输的快慢有带宽的限制。

[什么是带宽?比如你家用的是2M ADSL,那么带宽就是2M,此处的2M指2Mbps,就是250kb/s(2000/8)。

想想你下载的时候达到过带宽吗?由于一般服务器连接的客户端不止一个,服务器的带宽就会被分享。

当然服务器的带宽比自家大多了,一般都是光纤;没有特殊限制的话,服务器的带宽是等分的。

假设服务器的带宽是100M,即12500kb/s,有100台客户端连接,那么每一台分享到的带宽就是125kb/s,可见客户端的带宽没有完全发挥,为了弥补这种状况,flashget(网际快车)发明了多线程下载,这里就不深究了。

但是现实中,情况显然严重的多,大型软件下载站的访问量有多少大家可以百度百度。

网民越来越多,这种情况需要改变。

P2P就是在这种情况下诞生的。

下面转页就是P2P下载原理的示意图:如图所示,P2P下载时,服务器(sever)不再担任以前的http下载中服务器的角色,他只负责将文件的基本信息在客户端之间中转,本身并未存放任何文件。

P2P软件将文件被分成若干块,这里假设为A~Z块,客户端可以先下载K段再下载别的,没有固定的顺序,只要等最后文件被“填满”就完成了。

这样的好处就是,http下载中宕机了你就下不全了(虽然也有断点续传,不过现在随机地址越来越多了--+),使用P2P你就完全不必担心这一点,即使你没有M段,只要等有M段的人传给你就行了,而且在别人传给你的同时,你也在将自己完成的部分分享给没有此区块的人,这样就是分享。

双串口单片机(51单片机)

双串口单片机(51单片机)
特性?8位cmos微控制器?每4个时钟周期为一个机器周期的高速结构最大外部时钟频率为40mhz?与标准80c52管脚兼容?指令与mcs51兼容?4个8位io口?一个附加的4位io口和等待状态控制信号仅限44脚plccqfp封装?3个16位定时计数器?12个中断源2级中断能力?片上振荡器及时钟电路?二个增强型全双工串行口?32kbflasheprom?256字节片内暂存ram?片内1kb外部数据存储器用movx指令访问?可编程看门狗定时器?软件复位?2个16位数据指针?对外部ram及外设的访问周期可以进行软件编程?封装
15. 串行口 ...............................................................................................................................55 15.1 模式 0....................................................................................................................56 15.2 模式 1....................................................................................................................56 15.3 模式 2....................................................................................................................58 15.4 模式3.....................................................................................................................59 15.5 贞错误检测............................................................................................................59 15.6 多机通信 ...............................................................................................................60
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4月P2P问题平台达52家发生率为2.78% 网贷之家数据显示,4月P2P问题平台数量较上月有所减少,但仍有52家平台出现问题,问题平台发生率为2.78%。

4月问题平台注册资金普遍较低,大部分注册资金都在3000万元以下,且运营时间多在1年以内。

尽管P2P行业风险不断暴露,但是其热度并不减,截至今年4月底正常运营平台1819家,环比上涨5.27%。

4月新上线平台数量持续增加,达到143家。

从问题平台类型来看,跑路的平台有所减少,而提现困难的平台有所增加,使得跑路平台和提现困难平台数量占比均达到46%,另外,停业平台为4家,所占比例较小。

一位业内人士坦言,P2P发展已到瓶颈期,而最主要的原因就是征信问题没有解决,比如工商银行积累了海量信息,为什么要跟一个小P2P平台共享?更进一步讲,如果一个借款人在某机构逾期,该机构可能会对此保密,为的是他可以从别处借到钱,把这里的钱还了。

金融玩的就是击鼓传花游戏,谁都不想成为最后的接棒人。

理财范CEO申磊告诉《经济参考报》记者,征信对于P2P平台的风险识别和资产配置都有很重要的作用。

尤其借款方的债务水平和信用记录,将直接影响平台对其授信额度。

然而目前对于平台来说,做好征信是一个成本不菲的事情,不仅要花费大量的人力物力财力,甚至不一定能够查清借款方在其他平台或金融机构的债务明细。

所以不管是P2P平台之间的基础征信数据共享,还是接入银行征信系统,都非常必要。

“然而现实的情况是,一方面这些数据对于各家平台来说十分重要,行业又缺乏有资质有公信力的机构来搭建征信平台;另一方面,监管机构尚未出台相关监管政策,央行征信系统也没有准入P2P平台,所以目前P2P还无法和银行征信对接。

”申磊补充道。

据了解,众多P2P平台将目光投向民营征信机构。

但据多家平台负责人反馈,虽与多家机构合作,但发现无论接入哪家评分或征信机构,始终无法完美匹配。

同时,全国没有一个机构能够提供一份很完整的征信报告,P2P平台需要综合参考多份报告。

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