【单选题】
(71619)单相全波整流其输出直流电压平均值为输入交流电压的( )。(1.0分)___
A. 1倍
B. 0.9
C. 0.45
D. 0.7
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答案
B
解析
暂无解析
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【单选题】
(71620)轴温报警装置未联网的在运用客车质量鉴定中属于( )故障。(1.0分)___
A. A类
B. B类
C. C类
D. D类
【单选题】
(71621)GN-300型蓄电池充足电后,应能工作4小时45分以上,如果工作3小时30分电压就低于1.0 V时,此电池的容量损失为( )。(1.0分)___
A. 26.3%
B. 35.7%
C. 73.7%
D. 64.3%
【单选题】
(71622)在客车辅修时,制动盘整体厚度应不小于( )。(1.0分)___
A. 94 mm
B. 96 mm
C. 97 mm
D. 98 mm
【单选题】
(71623)单元式空调机组及控制柜中修周期为( )。(1.0分)___
A. 1年
B. 1.5年
C. 2年
D. 6年
【单选题】
(71624)在客车A1级检修时,应急电源电池电压低于( )时,欠压保护须起作用。(1.0分)___
A. 40 V±1 V
B. 42 V±1 V
C. 44 V±1 V
D. 45 V±1 V
【单选题】
(71625)在客车辅修质量对规中缓解阀作用不良,扣( )。(1.0分)___
A. 1分
B. 2分
C. 3分
D. 4分
【单选题】
(71626)三极管放大电路共有( )基本的接线方式(1.0分)___
A. 1种
B. 2种
C. 3种
D. 4种
【单选题】
(71627)在客车辅修质量对规中轴箱裂纹,每处扣( )。(1.0分)___
A. 2分
B. 3分
C. 4分
D. 5分
【单选题】
(71628)蓄电池大修后,同车蓄电池的容量差酸性不超过5%,碱性不超过( )。(1.0分)___
A. 5%
B. 8%
C. 110%
D. 50%
【单选题】
(71629)在客车A1级检修质量对规中电子防滑器单车静止试验出现故障显示,扣( )。(1.0分)___
A. 10分
B. 20分
C. 30分
D. 40分
【单选题】
(71630)在客车A1级检修质量对规中灯具点灯试验不良,每处扣( )。(1.0分)___
A. 2分
B. 3分
C. 4分
D. 5分
【单选题】
(71631)维持保养对蓄电池容量关系很大,在补液时一定保证注入的是( )(1.0分)___
A. 水
B. 纯水
C. 硫酸
D. 调整后的电解液
【单选题】
(71632)在客车A1级检修质量对规中空调系统各部滤网破损的每件扣( )。(1.0分)___
A. 2分
B. 3分
C. 4分
D. 5分
【单选题】
(71633)25Z型客车车下设有两路电源干线,每路容量为( )。(1.0分)___
A. 200 kW
B. 300 kW
C. 600 kW
D. 900 kW
【单选题】
(71634)装有毛细管的制冷系统,在压缩机停机后,需要( )才能再次启动。(1.0分)___
A. 1~2 min
B. 2~3 min
C. 3~5 min
D. 5 min以上
【单选题】
(71635)BSP客车电气系统的分类代码300系列表示( )。[313120210](1.0分)___
A. 供电系统
B. 照明系统
C. 空调系统
D. 轴报及制动系统
【单选题】
(71636)蓄电池充电时,电解液温度不超过( )。[311120204](1.0分)___
A. 45 ℃
B. 60 ℃
C. 70 ℃
D. 75 ℃
【单选题】
(71637)酸性蓄电池的大修周期是( )。[311120212](1.0分)___
A. 4.5年
B. 6年
C. 10年
D. 12年
【单选题】
(71638)荧光灯工作时,其电压波形是( )。[223110206](1.0分)___
A. 正弦波
B. 三角波
C. 近似矩形波
D. 无波形
【单选题】
(71639)当制冷系统( )时,压缩机易发生液击。[311110212](1.0分)___
A. 膨胀阀开度过小
B. 制冷剂充注过少
C. 冷冻机油充注过少
D. 蒸发器结霜过厚
【单选题】
(71640)( )不是空调系统制冷不足的原因。[311120212](1.0分)___
A. 冷冻室绝热性能差
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D. 制冷剂不足
【单选题】
(71641)当制冷系统混有较多空气时,会使( )。[311120211](1.0分)___
A. 压缩机排气压力稍大于冷凝压力
B. 压缩机排气温度增高
C. 压缩机功耗降低
D. 冷凝器水温水压不变时,冷凝压力降低
【单选题】
(71642)当停留车达( )时,在该车运用前,其蓄电池需充电。[311120204](1.0分)___
A. 1个月
B. 1.5个月
C. 2个月
D. 2.5个月
【单选题】
(71643)KP-2A型控制箱的三相输出线电压为( )。[311120204](1.0分)___
A. 42 V
B. 43 V
C. 44 V
D. 45 V
【单选题】
(71644)正常的蓄电池在充电后,按正常放电制进行放电,如果放出的容量达不到额定容量的( ),就叫容量损失。[311110504](1.0分)___
A. 90%
B. 95%
C. 98%
D. 100%
【单选题】
(71645)现有客车J5型发电机轴端传动装置采用标准长轴斜套型,采用B型三角皮带( )。[311120304](1.0分)___
A. 3根
B. 4根
C. 5根
D. 6根
【单选题】
(71646)可控硅正向阻断峰值电压的数值,规定比正向转折电压小( )。[221110206](1.0分)___
A. 100 V
B. 120 V
C. 150 V
D. 180 V
【单选题】
(71647)在规定的环境温度和控制极断路及元件导通的条件下,要维持元件继续导通所需的( )电流,叫维持电流。[231110206](1.0分)___
A. 最小正向
B. 最大正向
C. 最小反向
D. 最大反向
【单选题】
(71648)使用空调机组空气预热时,须先开启( ),再开启电热。[311120204](1.0分)___
A. 压缩机
B. 通风
C. 冷凝器
D. 制冷
【单选题】
(71649).合上开关后,日光灯不亮的可能原因是( )。[213120404](1.0分)___
A. 开关短路
B. 开关接在零线上
C. 电路断路
D. 导线太粗
【单选题】
(71650)J5型发电机的额定电压直流输出( )。[311120306](1.0分)___
A. 12 V
B. 36 V
C. 48 V
D. 59 V
【单选题】
(71651)客车蓄电池用蒸馏水用电导试验时,其绝缘值( )。[331120202](1.0分)___
A. >0.3 M
B. <0.3 M
C. ≥0.3 M
D. ≤0.3 M
【单选题】
(71652)铅酸蓄电池放电时,阴阳极板表面都会逐渐形成( )薄层。[311110206(1.0分)___
A. Pb
B. PbO
C. PbO2
D. PbSO4
【单选题】
(71653)铅酸蓄电池在充电后,阴极板上会逐渐形成( )薄层。[312110206](1.0分)___
A. Pb
B. PbO
C. PbO2
D. PbSO4
【单选题】
(71654)铅酸蓄电池在充电后,阳极板上会逐渐形成( )薄层。[313110206](1.0分)___
A. Pb
B. PbO
C. PbO
D. PbSO4
【单选题】
(71655)空调列车电力连接线长度一般应为( )。[311120202](1.0分)___
A. 1 400~1 500 mm
B. 1 500~1 600 mm
C. 1 600~1 700 mm
D. 1 700~1 800 mm
【单选题】
(71656)BSP新型客车,其供电形式为集中供电,电压为( ),三相四线制。[313110302](1.0分)___
A. DC 600 V
B. AC 380
C. DC 110 V
D. DC 48 V
【单选题】
(71657)BSP客车电气系统的分类代码100系列表示( )。[313110210](1.0分)___
A. 供电系统
B. 照明系统
C. 空调系统
D. 轴报及制动系统
【单选题】
(71658)BSP客车电气系统的分类代码200系列表示( )。[313120210](1.0分)___
A. 供电系统
B. 照明系统
C. 空调系统
D. 轴报及制动系统
【单选题】
(71659).BSP客车电气件的代号根据IEC标准编排,元件代码B表示( )。[313110228](1.0分)___
A. 空调温度传感器,压力开关
B. 照明,加热装置
C. 熔断器
D. 指示灯,喇叭
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【单选题】
On an ASA, which maps are used to identify traffic?___
A. Route maps
B. Policy maps
C. Class maps
D. Service maps
【单选题】
Which type of social engineering attack targets top executives?___
A. whaling
B. vishin
C. spear phishing ng
D. baiting
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What is the minimum Cisco lOS version that supports zone-based firewalls?___
A. 12.1T
B. 15.1
C. 15.0
D. 124
【单选题】
In which type of attack does an attacker overwrite an entry in the CAM table to divert traffic destined to a legitimate host?___
A. DHCP spoofing
B. ARP spoofing
C. CAM table overflow
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【多选题】
Which two attack types can be prevented with the impleme ntation of a Cisco IPS solution?___
A. DDos
B. man-in-the-middle
C. worms
D. ARP spoofing
E. VLAN hopping
【多选题】
choose four___
A. DHCP snooping ——————————blocks DHCP messages
B. Dynamic ARP inspection——————verifies IP-to-MAC traffic on untrusted ports
C. IP sources guard ——————————provides layer 2 interface security with ports ACLs
D. Port security————————————mitigates MAC-address spoofing at the access interface
【多选题】
choose four___
A. Step1————————run the system setup wizard
B. Step2————————add an authentication realm
C. Step3————————configure identity management
D. Step4————————configure directory group
【多选题】
What are two advanced features of the Cisco AMp solution for endpoints ___
A. contemplation
B. foresight
C. sandboxing
D. reputation
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Which two characteristics of RADIUS are true?___
A. It encrypts only the password between user and server.
B. It uses TCP ports 1812/1813
C. It uses UDP ports 1812/1813.
D. It uses UDP port 49
E. It uses TCP port 49
【多选题】
What are two challenges of using a network-based IPS? ___
A. It is unable to determine whether a detected attack was successful
B. It requires additional storage and proce ssor capacity on syslog servers
C. As the network expands, it requires you to add more sensors.
D. It is unable to detect attacks across the entire network
E. It must support multiple operating systems.
【多选题】
What are two default be haviors of the traffic on a zone-based firewall?___
A. Traffic within the self -zone uses an im plicit deny all.
B. All traffic between zones is implicitly blocked
C. Communication is allowed between interfadAss that are members of the same zone
D. Communication is blocked between interfaces that are members of the same zone
E. The CBAC rules that are configured on router interfaces apply to zone interfaces
【多选题】
Which two advantages does the on-premise model for MDM deployment have over the cloud-based model?___
A. The on-premise model is easier and faster to de ploy than the cloud-based model
B. The on-premise model is more scalable than the cloud-based model
C. The on-premise model is generally less expensive than the cloud-based model
D. The on-premise model generally has less latency than the cloud- based model.
E. The on-premise model provides more control of the MDM solution than the cloud
【多选题】
Which two actions can an end usts take to manage a lost or stolen device in Cisco ISE? ___
A. Activate Cisco ISE End point Protection Services to quarantine the device.
B. Add the mac address of the device to a list of blacklisted devices
C. Force the device to be locked with a PIN
D. Request revocation of the digital certificate of the device.
E. Reinstate a device that the user previously marked as lost or stolen
【多选题】
Which two problems can arise when a proxy firewall serves as the gateway between networks?___
A. It can prevent content caching
B. It can limit application support
C. It is unable to prevent direct connections to other networks
D. It can cause reduced throughput.
E. It is unable to provide antivirus protection
【多选题】
When using the Adaptive Security Device Manager(ASDM), which two methods are available to add a new root certificate?___
A. Use sCep
B. Install from SFTP server
C. Install from a file
D. Use Https
E. Use LDAP
【多选题】
Which two are considered basic security principles?___
A. Accountability
B. Redundancy
C. High Availabilit
D. Integrity
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【多选题】
Which two roles of the Cisco WSA are true?___
A. IPS
B. firewall
C. antispam
D. web proxy
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Which next-generation encryption algorithm supports four variants?___
A. SHA-2
B. SHA-1
C. MD5
D. HMAC
【单选题】
What aims to remove the abil ity to deny an action?___
A. Non-Repudiation
B. Accountability
C. Integrity
D. Deniability
【单选题】
Which statements about the native VLAN is true ?___
A. It is susceptible to VLAN hopping attacks.
B. It is the Cisco recommended VLAN for switch-management traffic
C. It is most secure when it is a ssigned to vLAn 1.
D. It is the cisco-recomme nded vlan for user traffic
【单选题】
There are two versions of IKE:IKEv1 and IKEv2. Both IKEv1 and IKEv2 protocols operate in phases IKEv1 operates in two phases. IKEv2 operates in how many phases?___
A. 2
B. 3
C. 4
D. 5
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What does the dh group refer to?___
A. length of key for hashing C
B. length of key for encryption
C. tunnel lifetime key
D. length of key for key exchange
E. length of key for authentication
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Which path do you follow to enable aaa through the SDM ?___
A. Configure Tasks > AAA
B. Configure > Addition Authentication > AAA
C. Configure > AAA
D. Configure > Additional Tasks > AAA
E. Configure Authentication > AAA
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which technology cloud be used on top of an MPLS VPN to add confidentiality ?___
A. IPsec
B. 3DES
C. AES
D. SSL
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Which term is most closely aligned with the basic purpose of a SIEM solution? ___
A. Non-Repudiation
B. Accountability
C. Causality
D. Repudiation
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You have just deployed SNMPv3 in your environment, Your manager asks you to make sure that our SNMP agents can only talk to the SNMP Manager. What would you configure on your SNMI agents to satisfy this request?___
A. A SNMP View containing the SNMP managers
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D. A SNMP Group containing the SNMP managers
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Which feature prevents loops by moving a nontrunking port into an errdisable state when a BPDU is received on that port?___
A. BPDU filte
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Which command enables port security to use sticky MAC addresses on a switch?___
A. switchport port-security violation restrict
B. switchport port-security mac-address sticky
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【单选题】
When you edit an IPS subsignature, what is the effect on the parent signature and the family of subsignatures?___
A. The change applies to the parent signature and the entire family of subsignatures
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C. The change applies only to subsignatures that are numbered sequentially after the subsignature that you edit
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Which type of mechanism does Cisco FirePOWER de ploy to protect ag detected moving across other networks?___
A. antivirus scanning
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What action must you take on the ise to blacklist a wired device?___
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【单选题】
Which type of firewall can perform deep packet inspection?___
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B. stateless firewall
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【单选题】
What is the main purpose of Control Plane Policing?___
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【单选题】
Which attack can be prevented by OSPF authentication?___
A. smurf attack
B. IP spoofing attack
C. denial of service attack
D. buffer overflow attack
【单选题】
What is the best definition of hairpinning?___
A. ingress traffic that traverses the outbound interface on a device
B. traffic that enters one interface on a device and that exits through another interface
C. traffic that enters and exits a device through the same interface
D. traffic that tunnels through a device interface
【单选题】
Which SNMPv3 security level provides authentication using HMAC with MD5, but does not use encryption?___
A. authPriv
B. authNo Priv
C. noAuthNoPriv
D. NoauthPriv
【单选题】
You have implemented a dynamic blacklist, using security intelligence to block illicit network activity. However, the blacklist contains several approved connections that users must access for usiness pur poses. Which action can you take to retain the blacklist while allowing users to access the approve d sites?___
A. Create a whitelist and manually add the approved addresses.
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C. Edit the dynamic blacklist to remove the approved addresses
D. Disable the dynamic blacklist and create a static blacklist in its place
【单选题】
When connecting to an external resource,you must change a source IP address to use one IP address from a range of 207.165.201.1 to 207.165.1.30. Which option do you implement ?___
A. dynamic source NAT that uses an IP ad dress as a mapped source
B. static destination NAT that uses a subnet as a real de stination
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D. static destination NAT that uses a subnet as a real source
【单选题】
Refer to the exhibit. 【nat(ins,any)dynamic interface】Which ty pe of NaT is configured on a Cisco ASA?___
A. dynamic NAT
B. source identity NAT
C. dynamic PAT
D. identity twice NAT
【单选题】
Which mitigation technology for web-based threats prevents the removal of confidential data from the network?___
A. CTA
B. DCA
C. AMP
D. DLP