【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
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答案
D
解析
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【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
【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
【单选题】
曲线区段上随曲线半径不同拉出值有差异,一般在150-400mm之间,拉出值的允许误差为正负( )。___
A. 20mm
B. 30mm
C. 40mm
D. 50mm
【单选题】
补偿器的a、b值主要受( )的变化而变化,接触线和承力索补偿器的a、b值( )。___
A. 环境 不相等
B. 环境 相等
C. 温度 不相等
D. 温度 相等
【单选题】
铁道部颁发的“接触网运行检修规程”规定,补偿器a、b值的最小值不小于( )。___
A. 100mm
B. 200mm
C. 300mm
D. 400mm
【单选题】
锚段便于在锚段两端给接触网导线和承力索加设补偿装置,以调整导线、承力索的( )。___
A. 高度
B. 结构高度
C. 拉出值
D. 张力与弛度
推荐试题
【多选题】
Which two configuration options can exclude virtual disks from snapshot operations? (Choose two.)___
A. Use RDM in virtual mode for virtual disk.
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C. Use a virtual disk larger than 2 TB in size.
D. Use RDM in physical mode for virtual disk.
【多选题】
Which two storage configurations on the source server are unsupported with VMware Converter? (Choose two.)___
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【多选题】
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A. ESXi 5.5 or later is required.
B. vCenter HA network latency between nodes must be less than 50 ms.
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E. SXi host cluster with DRS enabled.
【多选题】
An attempt to delete NFS datastore from a ESXi host returns the error: Sysinfo error on operation returned the following status:< Busy> Which two statements could explain this failure? (Choose two.)___
A. NFS datastore is a part of Storage DRS Cluster.
B. NFS.VolumeRemountFrequency value is set to 30.
C. Storage I/O Control is enabled on NFS datastore.
D. NFS datastore has running or registered virtual machines.
【多选题】
An administrator finds that the Microsoft Exchange virtual machines are exhibiting network latency. What two in-guest changes can help decrease latency? (Choose two.)___
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【多选题】
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A. dependent hardware
B. in-guest
C. software
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【多选题】
Which two statements are true for NFS v4.1 firewall behavior? (Choose two.)___
A. It closes port 2049.
B. It sets allowed. All flag to TRUE.
C. It sets allowed. All flag to FALSE.
D. It opens port 2049.
【多选题】
A vSphere Administrator attempts to enable Fault Tolerance for a virtual machine but receives the following error: Secondary VM could not be powered on as there are no compatible hosts that can accommodate it. What two options could cause this error? (Choose two.)___
A. The other ESXi host(s) are in Maintenance Mode.
B. Hardware virtualization is not enabled on the other ESXi host(s).
C. The other ESXi host(s) are in Quarantine Mode.
D. Hardware MMU is enabled on the other
E. SXi host(s).
【多选题】
Storage capabilities be populated in what two ways? (Choose two.)___
A. The administrator can use tags to describe capabilities.
B. Default capabilities are provided by vCenter Server.
C. Datastores can advertise their capabilities through VAAI.
D. Datastores can advertise their capabilities through VASA.
【多选题】
In network troubleshooting it is important to know what upstream switch the ESXi host is connected to. Which two features does ESXi provide to help identify the upstream switch? (Choose two.)___
A. Promiscuous mode
B. DPM
C. LLDP
D. CDP
【多选题】
Virtual Volumes supports which three VMware features? (Choose three.)___
A. Instant Clones
B. Distributed Resource Scheduler
C. Linked Clones
D. vMotion
E. Storage Distributed Resource Scheduler
【多选题】
vSphere DRS helps to balance virtual machines with available resources in a vSphere cluster. What three types of resources can be taken into account for balancing? (Choose three.)___
A. CPU
B. physical NIC saturation of an ESXi host
C. virtual NIC saturation of a virtual machine
D. RAM
E. storage latency
【多选题】
Which three design requirements must be satisfied to enable RAID-6 objects in a VMware vSAN cluster? (Choose three.)___
A. vSAN Advanced license or higher
B. vSAN stretched cluster
C. at least six hosts contributing storage
D. deduplication and compression
E. all flash configuration
【多选题】
When using "Cluster resource percentage" for host failover capacity in vSphere HA Admission Control, the total resource requirements are calculated from which two values? (Choose two.)___
A. Total vCPUs assigned to each VM.
B. Average CPU usage on each VM over time.
C. Memory reservations on each VM.
D. Total memory assigned to each VM.
E. Average active memory on each VM over time.
F. CPU reservations on each VM.
【多选题】
Which are four attributes of the Active vCenter HA node? (Choose four)___
A. It uses the vCenter HA network to communicate with the Witness node.
B. It constantly replicates vPostgres data with the Witness node.
C. It uses a public IP address for the management interface.
D. It runs the active vCenter Server Appliance instance.
E. It uses the vCenter HA network for replication of data to the Passive node.
F. It provides a quorum to protect against split-brain situations.
【多选题】
Which are two vCenter Server two-factor authentication methods? (Choose two.)___
A. RSA SecurID
B. Smart Card
C. SAML
D. Symantec VIP
【多选题】
An administrator is creating VMkernel adapters on an ESXi 6.5 host and wants to create separate VMkernel adapters for every type of traffic in the default TCP/IP stack. Which three types of traffic can be explicitly enabled on a separate VMkernel adapter? (Choose three.)___
A. Virtual SAN traffic
B. NFS traffic
C. vMotion traffic
D. vSphere HA traffic
E. Fault Tolerance logging traffic
【多选题】
When migrating a Windows vCenter Server 6.0 to the vCenter Server Appliance 6.5, which two will be migrated by default? (Choose two.)___
A. Local Windows OS users and groups
B. Configuration
C. Custom ports
D. FQDN
E. Historical and Performance data
【多选题】
Which three types of Content Libraries exist within vSphere 6.5? (Choose three.)___
A. Remote Content Library
B. Published Content Library
C. Local Content Library
D. Shared Content Library
E. Subscribed Content Library
【多选题】
An administrator cannot enable multi-processor Fault Tolerance (SMP-FT) for a virtual machine. Which are two possible causes for this? (Choose two.)___
A. The virtual machine is running on a vSAN datastore.
B. The Fault Tolerance network is using a 10Gbit uplink.
C. The virtual machine has 6 vCPUs assigned.
D. The virtual machine has a 1TB VMDK attached.
E. The virtual machine has snapshots present.
【多选题】
Which two statements are true for Predictive DRS? (Choose two.)___
A. It balances resource utilization for virtual machines with unpredictable utilization patterns.
B. It integrates DRS with vRealize Operations Manager to balance workloads for virtual machines before resource utilization spikes occur.
C. It balances resource utilization based on a threshold's algorithm that runs each night.
D. It determines the best placement and balance of virtual machines based on a threshold's algorithm that runs each night in vCenter Server 6.5 Database.
【多选题】
Which two situations could cause a virtual machine to appear with (orphaned) appended to its name? (Choose two.)___
A. if a host failover is unsuccessful
B. if a virtual machine was removed from vCenter Server's inventory
C. if a virtual machine was deployed from template, and the template has been deleted
D. if a virtual machine is unregistered directly on the host
【多选题】
Which three requirements are needed to apply RAID 5 or RAID 6 erasure coding on a vSAN 6.2 or 6.5 object? (Choose three.)___
A. on Disk Format 3.0
B. Hybrid vSAN
C. All Flash vSAN
D. vSAN Advanced License
E. Stretched Cluster Configurations
【多选题】
An administrator sees the following error in the log files: Which two events could be the source of the error message? (Choose two.)___
A. vCenter Server failure
B. VXLAN failure
C. Disk array failure
D. Network failure
E. ESXi host failure
【多选题】
An administrator is attempting to access an ESXi host via the DCUI but is unable to do so. Which could be two possible causes? (Choose two.)___
A. The host in Qhas no out-of-band management capability (i.e. iLO/iDRAC).
B. The SSH service is disabled on the host.
C. Strict lockdown mode is enabled on the host.
D. Normal lockdown mode is enabled and the administrator is a member of the
E. xception User list.
【多选题】
Which two permissions are required to migrate a virtual machine with Storage vMotion? (Choose two.)___
A. Network > Move Network
B. Virtual Machine > Inventory > Move
C. Resource > Migrate powered on virtual machine
D. Datastore > Allocate Space
【多选题】
Which are three supported storage requirements for vCenter Server HA? (Choose three.)___
A. NFS
B. RDM
C. vSAN
D. VMFS
E. JBOD
【多选题】
Which are the two network requirements for a VMware vSAN 6.5 cluster? (Choose two.)___
A. Multicast must be enabled on the physical switches and routers that handle vSAN traffic.
B. vSAN requires IPv6 only.
C. All hosts must have a dedicated 40GbE NIC.
D. The vSAN network supported IPv4 or IPv6.
E. vSAN requires IPv4 only.
【多选题】
Which three prerequisites must be in place prior to enabling secure boot for a virtual machine? (Choose three.)___
A. VirtualMachine.Config.Settings privileges
B. an encrypted USB drive
C. Virtual Hardware version 13 or later
D. Virtual Hardware version 12 or later
E. EFI firmware
【多选题】
A user is given the "Virtual machine user (sample)" role in a vSphere 6.x environment. Which three permissions would the user be able to perform? (Choose three.)___
A. Reset a virtual machine.
B. Power on a virtual machine.
C. Move a host into a cluster.
D. Configure CD media.
E. Migrate a virtual machine with Storage vMotion.
【多选题】
Which three are supported upgrade processes for ESXi host? (Choose three.)___
A. using vSphere Auto Deploy
B. using a TFTP server
C. using Update Manager
D. using an
E. SXCLI command
【多选题】
When enabling Storage DRS on a datastore cluster, which three components are enabled as a result? (Choose three.)___
A. Space load balancing among datastore within the datastore cluster.
B. Initial placement for virtual disks based on space and I/O workload.
C. I/O load balancing among datastores within the datastore cluster.
D. Queue Depth alerting on disks within the datastore cluster.
E. Data de-duplication within the datastore cluster.
【多选题】
What are two features introduced in Network I/O Control version 3? (Choose two.)___
A. Bandwidth reservation per traffic type
B. Network resource pools
C. CoS tagging
D. Bandwidth guarantee to virtual machines
【多选题】
Which two correct virtual machine advanced configuration parameters will accomplish this? (Choose two.)___
A. isolation.device.edit.disable = “FALSE”
B. isolation.device.edit.disable = “TRUE”
C. isolation.device.connectable.disable = “FALSE”
D. isolation.device.connectable.disable = “TRUE”
【多选题】
Which three statements are correct regarding booting an ESXi Host from Fibre Channel SAN? (Choose three.)___
A. Direct connect topology is supported.
B. Each host must have its own boot LUN.
C. ESXi hosts do not require local storage.
D. Multipathing to a boot LUN on an active-passive array is supported.
E. Hosts can share one common boot LUN.
【多选题】
Which two tasks should a vSphere administrator perform if the vmkernel log reports VMFS metadata errors? (Choose two.)___
A. contact VMware technical support
B. reformat the datastore
C. check the device with VOMA
D. ignore the messages
【多选题】
Which two statements are true for a vCenterServer user account that is used for vSphere Data Protection (VDP)? (Choose two.)___
A. The user account must be assigned with Administrator role.
B. The password for the user account cannot contain spaces.
C. The user account should be created in the Single Sign-On domain
D. The user account cannot inherit required permissions from a group role.
【多选题】
Which three storage protocols are supported by Virtual Volumes? (Choose three.)___
A. FCIP
B. FCoE
C. iSCSI
D. NFS v3
E. NFS v4
【多选题】
A vSphere administrator observes a CPU spike on one of the web servers (view the Exhibit.) Which two statements can describe the cause of this activity? (Choose two.)___
A. The network packet size is too large.
B. VMware Tools is not installed.
C. Disk latency is present on the datastore.
D. The network packet size is too small.
【多选题】
Which three operations can cause VMFS metadata updates? (Choose three.)___
A. Restarting a VM using the guest OS.
B. Launching a VM console.
C. Migrating a VM with vMotion.
D. Powering a VM on or off.
E. Expanding a VMFS datastore.