【单选题】
曲线区段上随曲线半径不同拉出值有差异,一般在( )之间。___
A. 150-300mm
B. 150-400mm
C. 150-500mm
D. 150-600mm
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答案
B
解析
暂无解析
相关试题
【单选题】
接触线是直接和受电弓滑板相接触并摩擦的,电动列车从( )上取得电能。___
A. 吊索
B. 吊弦
C. 承力索
D. 接触线
【单选题】
那种绝缘子性能反映了防雷需求的电气性能指标。___
A. 干闪络电压
B. 湿闪络电压
C. 击穿电压
D. 工作电压
【单选题】
击穿电压至少应比干闪电压高( )倍。___
A. 1
B. 5
C. 2
D. 3
【单选题】
绝缘子除起电气性能外,还承受一定的机械负荷。因此,要求绝缘子有一定的安全系数,一般绝缘子安全系数规定为( )。___
A. 1~5
B. 2~5
C. 5~3
D. 3~5
【单选题】
绝缘子要求质地紧密均匀,任何一个断面上不能有裂纹和气孔,表面( )后可防止水分的渗入。___
A. 冷处理
B. 热处理
C. 剖光
D. 涂釉
【单选题】
新购、制作(或大修)后,接触网检修工具在第一次投入使用前进行( )和电气强度试验。___
A. 机械
B. 电容
C. 绝缘
D. 电压
【单选题】
棒式绝缘子用在( )上、隧道内悬挂和隧道内定位等处。___
A. 承受拉力
B. 承受扭矩
C. 承受悬挂
D. 绝缘腕臂
【单选题】
液压压接钳一般为专用型和较大尺寸的压接,( )KN。机械压接钳为小尺寸的压接,69KN。___
A. 300
B. 180
C. 200
D. 110
【单选题】
螺纹联接拧紧对于受拉螺栓连接,可提高螺栓的()。___
A. 刚性
B. 紧密性
C. 防松
D. 疲劳强度
【单选题】
三角形螺纹的牙形为( ),当量摩擦系数大,自锁性好,主要用于联接。___
A. 30°
B. 45°
C. 55°
D. 60°
【单选题】
圆锥螺纹不用填料而靠牙的( )来保证螺纹副的紧密性。___
A. 自锁
B. 摩擦
C. 贴合
D. 变形
【单选题】
螺纹联接是利用( )构成的可拆联接。___
A. 螺纹零件
B. 摩擦零件
C. 机械零件
D. 零件间隙
【单选题】
温度变化时,线索受温度影响而伸长或缩短,由于()坠砣的重量作用,可使线索沿线路方向移动而自动调整线索张力,使张力恒定不变,并借以保持线的驰度满足技术要求。___
A. 补偿器
B. 控制器
C. 断路器
D. 短路器
【单选题】
接触线在夏季随着温度升高触线长度( )___
A. 缩短
B. 不变
C. 无规律
D. 增加
【单选题】
下锚补偿装置检查时注意大、小轮补偿绳是否有磨擦棘轮现象,小轮补偿绳张力是否一致,平衡轮是否处于( )平衡状态___
A. 垂直
B. 水平
C. 30°倾斜
D. 拉力
【单选题】
中国大陆称接触网供电或架空接触网,台湾称高架电缆或架空电缆,是( )铁路常用的两种供电网络方式之一。___
A. 步行
B. 电气化
C. 机电
D. 架空
【单选题】
在铁路和城市轨道交通系统中,架空接触网只有导线的一个电极,电力机车通过集电装置取电,再通过()回流到电网中。___
A. 电缆线
B. 变频器
C. 金属轮轨
D. 人工方式
【单选题】
用验电器验电的顺序是:将验电器上端挂在接触线(汇流排)上,验电器表计端头靠到钢轨上,指示灯不亮,读数表为( ),为已停电。 ___
A. 0
B. ∞
C. 100V
D. 1000V
【单选题】
验电器使用前需要到( )带电设备试验,确认验电器功能完好。___
A. 交流
B. 直流
C. 高压
D. 同电压等级
【单选题】
吊弦的长度要能适应在极限温度范围内接触线的()的变化。___
A. 伸缩
B. 弛度
C. 伸缩和弛度
D. 导线高度
【单选题】
吊弦喜爱垂直线路方向的偏移角不得大于( )。___
A. 10°
B. 15°
C. 20°
D. 25°
【单选题】
要求承力索能够承受较大的( )和具有抗腐蚀能力,并且在温度变化时驰度变化较小。___
A. 拉力
B. 压力
C. 张力
D. 应力
【单选题】
铜( )导电性能好,可做牵引电流的通道之一,和接触网并联供电,降低压损和能耗,且抗腐蚀性能提高。___
A. 吊索
B. 吊弦
C. 承力索
D. 接触线
【单选题】
承力索的主要作用是通过吊弦将接触线悬吊起来,提高悬挂的稳定性,与接触线( )供电。___
A. 串联
B. 并联
C. 分段
D. 并列
【单选题】
TJ120绞线的根数为( )。___
A. 18
B. 19
C. 20
D. 21
【单选题】
TJR120表示( )。___
A. 截面积为120mm2的软铜绞线
B. 截面积为120mm2的硬铜绞线
C. 截面积为120m2的软铜绞线
D. 截面积为150m2的软铜绞线
【单选题】
。用聚酯丙烯纤维制成的各类合成纤维绳用于合成树脂腕臂的紧固、滑轮悬挂和软横跨。这些绳索起到()。___
A. 机械作用
B. 绝缘作用
C. 机械和绝缘的作用
D. 非绝缘作用
【单选题】
由于交流电通过导体时会发生集肤效应,其( )电阻不是均匀分布的。___
A. 内部
B. 外部
C. 阻抗
D. 截面
【单选题】
线索在温度升高或降低时发生变形的常量,即单位长度的金属线索在( )变化摄氏一度时的伸缩量。___
A. 温度
B. 环境
C. 外力
D. 应力
【单选题】
表示线索性能的综合拉断力是金属材料在拉伸(或压缩),剪切,弯曲等各种外力作用下,发生断裂时的外力( )。___
A. 拉力
B. 压力
C. 外力
D. 应力
【单选题】
表示线索性能的综合拉断力的单位是( )。___
A. N
B. 10N
C. 100N
D. KN
【单选题】
线索性能的抗拉强度表示金属材料抵抗( )变形的能力,单位Pa。___
A. 旋转
B. 拉伸
C. 纵向
D. 横向
【单选题】
抗拉强度有材料单位面积上能承受( )的大小来决定。___
A. 拉力
B. 压力
C. 张力
D. 应力
【单选题】
银含量( )或镁含量(0.5%)的合金添加剂用来进一步改善铜线的机械和热性能,从而得以使用较高张力的铜线。___
A. 0.001
B. 0.002
C. 0.003
D. 0.004
【单选题】
接触线允许磨损率被限制为原截面积的( )。___
A. 10%~20%
B. 20%~30%
C. 30%~40%
D. 40%~50%
【单选题】
( )的选择主要取决于所需的电流、电压的稳定性和施加的张力。___
A. 接触线形状
B. 接触线材料
C. 接触线截面积
D. 接触线重量
【单选题】
采用合金的目标是提高接触线的( )、耐磨耗性能和高温软化性能___
A. 抗拉强度
B. 塑性
C. 硬度
D. 导电性能
【单选题】
( )制成带沟槽的圆柱状,沟槽便于安装线夹,固定接触线又不影响受电弓取流。___
A. 吊索
B. 吊弦
C. 承力索
D. 接触线
【单选题】
架空接触线的首选截面为( )。___
A. 圆形
B. 直线状
C. 方形
D. 曲线状
【单选题】
( )既要有足够的机械强度又要有良好的电气性能。___
A. 吊索
B. 吊弦
C. 承力索
D. 接触线
推荐试题
【单选题】
An administrator is attempting to enable Storage I/O Control on a datastore, but it is failing. What is the likely reason for this failure? ___
A. The host is connected to a datastore is running on ESX 4.0.
B. The host is connected to a Fibre Channel storage array.
C. The datastore has multiple extents.
D. The datastore is managed by a single vCenter Server.
【单选题】
A mission-critical virtual machine built on vSphere 4.1 needs to be moved to an ESXi 6.x host.Which virtual hardware version is needed to move the virtual machine without upgrading? ___
A. 6
B. 7
C. 10
D. 11
【单选题】
An administrator is analyzing a virtual machine as shown in the Exhibit. What is the current long term risk for this virtual machine? ___
A. The virtual machine may run out of memory before April 27.
B. The virtual machine may continue to function after April 27.
C. The virtual machine has adequate memory configured for operation for the next 120 days.
D. The virtual machine has adequate memory reservation configured for operation for the next 120 days.
【单选题】
An administrator is monitoring a High Availability (HA) and Distributed Resource Scheduler (DRS) enabled cluster and has noticed that virtual machines in the cluster are being migrated without user intervention. Why is this happening? ___
A. The DRS Automation level is set to Fully Automated.
B. The Automation level is set to Automatic.
C. The
D. PM Threshold is set to Aggressive.
【单选题】
An administrator attempts to migrate a suspended virtual machine to a newly deployed vSphere 6.x cluster. The compatibility check fails. What condition could cause this behavior?___
A. The new vSphere 6.x cluster is running Intel CPUs instead of AMD CPUs.
B. A suspended virtual machine cannot be migrated.
C. The hardware virtualization feature of the CPU is not enabled on the new hosts.
D. A vSphere Distributed Switch is required to migrate a suspended virtual machine.
【单选题】
A vSphere administrator has been using vSphere in evaluation mode and now wants to deploy an environment that provides the same features. Which edition of vSphere provides similar functionality to evaluation mode? ___
A. Enterprise Plus
B. Enterprise
C. Standard
D. Essentials
【单选题】
A vSphere administrator has been using vSphere in evaluation mode and now wants to deploy an environment that provides the same features. Which edition of vSphere provides similar functionality to evaluation mode? ___
A. Enterprise Plus
B. Enterprise
C. Standard
D. Essentials
【单选题】
An administrator has just configured the IP address on an ESXi host from the Direct Console User Interface. How can the configuration be validated as correct without any additional tools?___
A. Add the host to vCenter Server and if it works, then all networking settings are ok.
B. Select the Test Management Network option from the DCUI.
C. Connect to the host with the vSphere Client and click the Test Network option.
D. Use PowerCLI to connect to the host and initiate a network test.
【单选题】
An administrator is installing vCenter Server for an environment that has 40 ESXi 6.x Hosts and 150 virtual machines. Which database would meet the minimal requirements needed for this task? ___
A. vFabric Postgres
B. Microsoft SQL Express 2008
C. Microsoft SQL Server 2014
D. Oracle 11g
【单选题】
What is a requirement when enabling a Virtual SAN cluster in an existing High Availability (HA) and Distributed Resource Scheduler (DRS) Cluster? ___
A. Disable DRS and HA before enabling Virtual SAN
B. Enable DRS before enabling Virtual SAN
C. Disable HA before enabling Virtual SAN
D. Enable Storage DRS before enabling Virtual SAN
【单选题】
The vSphere administrator attempts to connect to an ESXi host via an SSH client and receives the following security alert: The vSphere administrator needs to determine whether the RSA key fingerprint shown in the security alert is the fingerprint of the intended ESXi host. Which tool should the vSphere administrator use? ___
A. Direct Console User Interface
B. vSphere Client
C. vSphere Web Client
D. vSphere Management Assistant
【单选题】
An administrator needs to monitor traffic on vSwitches in a vSphere 6.x environment. Which option, if configured, would accomplish this task? ___
A. Forged Transmits
B. MAC Address Changes
C. Promiscuous Mode
D. Notify Switches
【单选题】
What is true regarding datastores on ESXi 6.x? ___
A. NFS 4.1 datastore does not support Fault Tolerance (FT)
B. VMFS3 and VMFS5 datastores can be newly created
C. NFS datastore can be concurrently mounted using NFS 4.1 on one host and NFS on another
D. NFS 3.0 datastore does not support Fault Tolerance (FT)
【单选题】
An administrator is cloning and configuring five new web server virtual machines. What would be the benefit of configuring resource shares for the new VMs? ___
A. To prioritize access to a resource during contention.
B. To guarantee access to a resource during contention.
C. To prioritize access to a resource before contention occurs.
D. To guarantee access to a resource before contention occurs.
【单选题】
An administrator logs into the vSphere Web Client and sees the warning shown in the Exhibit. During a change control window, the warning was addressed. What should be done to verify that the host is no longer showing the warning? ___
A. Run a Remediate host operation.
B. Recheck the compliance of the host.
C. Restart the host to get rid of the warning.
D. Install VMware tools to clear the warning.
【单选题】
A vApp named Sales has a Memory Limit of 32 GB and a CPU Limit of 12,000 MHz. There are three virtual machines within the vApp: <Sales-DB -- Has a memory reservation of 20 GB. > <Sales-DC -- Has a memory reservation of 8 GB. > <Sales-Web -- Has a memory reservation of 8 GB.> Which statement is correct? ___
A. All three virtual machines can power on, but will have memory contention.
B. All three virtual machines can power on without memory contention.
C. Only two of the three virtual machines can power on.
D. Only one of the virtual machines can power on.
【单选题】
You are editing the management network configuration of an ESXi 6.x Host from the vSphere Web Client. You mistakenly put the incorrect VLAN in place for the management network. What action do you need to take to correct this? ___
A. You need to manually edit the configuration on the host with command line utilities.
B. No action is required. By default ESXi rolls back configuration changes that disconnect the host.
C. The ESXi host system configuration will need to be restored to the factory configuration to fix the issue.
D. The change can be reverted in the vSphere Web Client by simply editing the switch again.
【单选题】
What is true about resource pools created on a Distributed Resource Scheduler (DRS) cluster?___
A. A root resource pool is created with the specified values.
B. A root resource pool is automatically created using the aggregate total of the ESXi host resources in the cluster.
C. A root resource pool is automatically created using the aggregate total of all resources in the datacenter.
D. A root resource pool is not needed when creating resource pools on a DRS cluster.
【单选题】
An administrator attempts to enable Enhanced vMotion Compatibility (EVC) on a cluster. The operation results in a compatibility error, as shown in the exhibit. What is the likely cause of this error? ___
A. The CPUs in the ESXi host are not AMD CPUs.
B. The CPUs in the ESXi host do not support hardware virtualization capabilities.
C. The XD/NX CPU features have not been enabled in the BIOS of the server.
D. There is no shared storage between the hosts in the cluster.
【单选题】
What condition would prevent an administrator from creating a new VMFS3 datastore on an ESXi 6.x host using the vSphere Web Client? ___
A. A VMFS3 datastore cannot be created on an ESXi 6.x host.
B. The VMFS3 kernel module is not loaded.
C. A VMFS3 datastore cannot be mounted on an ESXi 6.x host.
D. VMFS3 datastores are not compatible with virtual machines created on an
E. SXi 6.x host.
【单选题】
During a new vSphere Distributed Switch configuration, where does the Maximum Transmission Unit (MTU) value get modified? ___
A. Uplink Settings
B. Switch Settings
C. Portgroup Settings
D. NIC Teaming Settings
【单选题】
A small company wants to use VMware products for its production systems. The system administrator needs to recommend a solution that will deliver High Availability to the company's production applications. What is minimum vSphere offering that will support this requirement? ___
A. vSphere Essentials
B. vSphere Essentials Plus
C. vSphere Hypervisor
D. vSphere Standard
【单选题】
Which scenario shows a reason for VMware Tools failing to install? ___
A. Virtual machine has a CD-ROM configured.
B. Guest OS Antivirus is blocking the VMware Tools installation.
C. Guest OS has 64-bit ldd (list dynamic dependencies) utility installed.
D. Virtual machine is powered on.
【单选题】
An administrator is configuring an ESXi 6.x host to use multiple NICs to resolve a management network redundancy error. After configuring a second NIC, the server is not able to communicate when the primary connection is taken down. The administrator analyzes the Exhibit shown here. Based on the exhibit, what is the likely cause of the issue? ___
A. vmnic4 is not attached to a vSwitch.
B. vmnic2 is not connected to a physical switch.
C. E1000 is the incorrect NIC
D. river for this card.
【单选题】
What information is required as part of an interactive ESXi 6.x installation? ___
A. Keyboard layout
B. IP Address
C. Root password
D. DNS information
【单选题】
What is the default load balancing policy for a newly created VMkernel port on a vSphere Distributed Switch? ___
A. Route based on orginating virtual port ID
B. Route based on IP Hash
C. Route based on source mac address
D. Route based on physical NIC load
【单选题】
An administrator deploys vCenter Server using the embedded Platform Services Controller. After testing the deployment for a couple of months, it is determined that the environment would be better served with an external Platform Services Controller. What should the administrator do to meet this new requirement? ___
A. Deploy a fresh instance of vCenter Server with an external Platform Services Controller.
B. Perform a fresh install of an external Platform Services Controller.
C. Migrate the embedded Platform Services Controller to an external Platform Services Controller.
D. Upgrade the embedded Platform Services Controller to an external Platform Services Controller.
【单选题】
Why are some virtual machines orphaned after rebooting a High Availability (HA) enabled host? ___
A. The Orphaned virtual machines have HA restart disabled.
B. The Orphaned virtual machines moved recently and the change did not persist.
C. The host is attached to failed storage.
D. The host just came out of maintenance mode.
【单选题】
Which vSphere 6 Standard Edition feature will allow an organization to ensure that critical multi-threaded applications have the maximum possible uptime? ___
A. Fault Tolerance
B. High Availability
C. Distributed Resource Scheduler
D. App HA
【多选题】
An application running in a virtual machine is experiencing performance issues. When utilizing performance monitoring utilities, it is noted that the CPU Utilization of the application is at 100%. Which two scenarios are probable causes of the CPU contention for the application? (Choose two.)___
A. There is a network I/O constraint.
B. There is a storage I/O constraint.
C. There is insufficient disk space assigned to the virtual machine.
D. The application is not virtualization aware.
【多选题】
A Fault Tolerance (FT) virtual machine with four vCPUs is experiencing high latency when performing ICMP and Application tests. What are three potential causes that may be attributing to this latency? (Choose three.)___
A. The FT network has insufficient bandwidth and is running on a 1GB Link.
B. The FT network is on a particularly high latency link.
C. The FT network has been configured with Network I/O Control.
D. The FT virtual machine is running an e1000 network adapter.
E. The
F. T virtual machine is running on poor performing network-based storage.
【多选题】
A virtual machine is experiencing performance issues. The following performance metrics are observed: <CPU usage value for the virtual machine is above 90%> < CPU ready value for the virtual machine is above 20%> Which two activities will likely resolve the performance issues? (Choose two.)___
A. Set a CPU reservation for the virtual machine.
B. Increase the CPU limit on the virtual machine.
C. Decrease CPU shares equally for all virtual machines on the host.
D. Increase CPU shares equally for all virtual machines on the host.
【多选题】
An administrator is upgrading a vSphere Distributed Switch. The existing switch is version 6.0 and the administrator wants to upgrade to the latest version possible. The environment contains several ESXi 6.1 hosts. Which two options are available to ensure that the upgraded switch will be compatible with these hosts? (Choose two.)___
A. Upgrade the vSphere Distributed Switch to 6.0
B. Upgrade the ESXi 5.5 hosts to version 6.0, then upgrade the vSphere Distributed Switch to 5.5
C. Upgrade the vSphere Distributed Switch to 5.1
D. Upgrade the
E. SXi host switches to 5.5, then upgrade the vSphere Distributed Switch to 5.5
【多选题】
An administrator attempts to create a Thick Provisioned Virtual Disk (VMDK) on an NFS datastore; but it fails. Which two reasons would explain the failure? (Choose two.)___
A. Datastore is on an NFS 3 storage server that does not support Hardware Acceleration
B. Datastore is on an NFS 4.1 storage server
C. Only VMFS datastores support "Thick Provisioned" VMDK
D. The NFS datastore was not created on a "Thick Provisioned" device
【多选题】
Which two NFS Protocol versions does vSphere 6 support? (Choose two.)___
A. Version 3
B. Version 3.1
C. Version 4
D. Version 4.1
【多选题】
Which three operations occur during a cold migration of a virtual machine? (Choose three.)___
A. The virtual machine disks are moved if the datastore is being changed.
B. The virtual machine is registered with the destination server.
C. The source virtual machine is removed from the old hosts.
D. The virtual machine hardware is upgraded.
E. The virtual machine files are quiesced prior to the migration.
【多选题】
A 4 GB Memory virtual machine is experiencing extended memory issues, as shown in the Exhibit. What potential issues could be attributed to this memory pressure?___
A. A limit is imposed on the virtual memory of this virtual machine.
B. The Balloon driver has been uninstalled.
C. A limit has been imposed on the Virtual CPU of the virtual machine.
D. Storage IO control has been enabled for the virtual machine causing the swapped memory.
【多选题】
You are creating a virtual machine in the Web Client using the New Virtual Machine wizard. Which two steps are required? (Choose two.)___
A. Select a valid name.
B. Select a cluster for the compute resource.
C. Select a network adapter.
D. Select the virtual machine compatibility.
【多选题】
An administrator has been given requirements to configure vMotion for a new virtual machine. The configuration should: <Provide Network Redundancy Use VLAN 550> <Be secured against anyone trying to spoof communication The vSwitch1 configuration is shown in the Exhibit.> Which three changes should be made to meet the stated requirements? (Choose three.)___
A. The VLAN ID must be set appropriately.
B. The default values for MAC Address Changes and Forged Transmits must be altered.
C. The teaming and failover adapters must be set appropriately.
D. The Traffic Shaping configuration must be altered.
E. The Load Balancing Policy must be set appropriately.
【多选题】
Which three traffic types are available services options when configuring a vmkernel port? (Choose three.)___
A. Provisioning Traffic
B. Virtual Volumes Traffic
C. vSphere Replication NFC Traffic
D. Virtual SAN Traffic
E. FCoE Traffic