【判断题】
>在感性负载两端并联适当的电容器后,可使通过感性负载的电流量减小,使电路的功率因数得到改善
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>在交流与直流接触器中,铁芯都是用来导磁的,所以二者的铁芯可以通用
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>在安装电流互感器时,铁芯和副边要同时可靠的接地
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>零件拆卸时,拆卸前应先量得一些主要装配尺寸和校验一些主要精度
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>变压器是一种利用电磁感应的原理,将某一数值的交流电压转变为频率相同的另一种或两种以上的交流电压的电气设备
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>多速异步电动机的结构和一般异步电动机相似,不同的是定子绕组的接线,试车前一定要检查接线是否正确
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>只要三相定子绕组每相都通入交流电流,便可产生定子旋转磁场
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>单相异步电动机的体积虽然较同容量的三相异步电动机大,但功率因数、效率和过载能力都比同容量的三相异步电动机低
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>交流伺服电动机的工作原理和单相电容式异步电动机相同
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>直流电机在更换半数以上的电刷之后,最好先以1/4~1/2额定负载运行10h以上,使电刷有较好配合后再满载运行
【判断题】
>直流电机电枢对地短路,一种是电枢绕组对地短路;另一种是换向器对地短路
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>电机的轴承套到轴径上有冷套和热套两种方法
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>自感电动势的大小正比于线圈中电流的变化率,与线圈中电流的大小无关
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>有中性线的三相供电方式叫三相四线制,它常用于低压配电系统
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>三相对称电源接成三相四线制,目的是向负载提供两种电压,在低压配电系统中,标准电压规定线电压为380V,相电压为220V
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>电焊变压器的副边短路时,其短路电流必然很大
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>晶闸管的控制极既可以控制它的导通,也可以控制它的关断
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>晶闸管的控制极既不能控制它的导通,也不能控制它的关断
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>晶闸管的控制极可以控制它的导通,但不能控制它的关断
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>晶闸管的控制极不可以控制它的导通,但能控制它的关断
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【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
E. Confidentiality
【多选题】
Which two roles of the Cisco WSA are true?___
A. IPS
B. firewall
C. antispam
D. web proxy
E. URL filter
【单选题】
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?___
【单选题】
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
【单选题】
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
【单选题】
which technology cloud be used on top of an MPLS VPN to add confidentiality ?___
A. IPsec
B. 3DES
C. AES
D. SSL
【单选题】
Which term is most closely aligned with the basic purpose of a SIEM solution? ___
A. Non-Repudiation
B. Accountability
C. Causality
D. Repudiation
【单选题】
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
B. Routing Filter with the SNMP managers in it applied outbound
C. A standard ACL containing the SNMP managers applied to the SNMP configuration
D. A SNMP Group containing the SNMP managers
【单选题】
Which feature prevents loops by moving a nontrunking port into an errdisable state when a BPDU is received on that port?___
A. BPDU filte
B. DHCP snooping
C. BPDU guard
D. Port Fast
【单选题】
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
C. switchport port-security violation protect
D. switchport port-security
【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
B. The change applies to the parent signature and the subsignature that you edit
C. The change applies only to subsignatures that are numbered sequentially after the subsignature that you edit
D. Other signatures are unaffected, the change applies only to the subsignature that you dit
【单选题】
Which type of mechanism does Cisco FirePOWER de ploy to protect ag detected moving across other networks?___
A. antivirus scanning
B. policy-based
C. reputation-based
D. signature-based
【单选题】
What action must you take on the ise to blacklist a wired device?___
A. Locate the switch through which the device is connected and push an a cl restricting all access by the device
B. Issue a CoA request for the de vice's mac address to each access switch in the network
C. Revoke the device's certificate so it is unable to authenticate to the network
D. Add the device's MAc address to a list of black listed devices
【单选题】
Which type of firewall can perform deep packet inspection?___
A. packet-filtering firewall
B. stateless firewall
C. application firewall
D. personal firewall
【单选题】
What is the main purpose of Control Plane Policing?___
A. to prevent exhaustion of route-proce ssor resources
B. to organize the egress packet queues
C. to define traffic classes
D. to maintain the policy map
【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.
B. Disable the dynamic blacklist and deny the specif ic address on a whitelist while permitting the others
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
C. dynamic source NAT that uses a range as a mapped source
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
【单选题】
Refer to the exhibit. What is the effect of the given configuration?___
A. It establishes the preshared key for the switch
B. It establishes the preshared key for the firewall.
C. It establishes the preshared key for the Cisco ISE appliance
D. It establishes the preshared key for the router.
【多选题】
What are two major considerations when choosing between a SPAN and a TAP when plementing IPS?___
A. the type of analysis the iS will perform
B. the amount of bandwidth available
C. whether RX and TX signals will use separate ports
D. the way in which media errors will be handled
E. the way in which dropped packets will be handled
【多选题】
What are two direct-to-tower methods for redirecting web traffic to Cisco Cloud Web Security?___
A. third-party proxies
B. Cisco Catalyst platforms
C. Cisco NAC Agent
D. hosted PAC files
E. CiSco ISE
【多选题】
Which three descriptions of RADIUS are true? ___
A. It uses TCP as its transport protocol.
B. Only the password is encrypted
C. It supports multiple transport protocols
D. It uses UDP as its transport protocol
E. It combines authentication and authorization
F. It separates authentication,authorization,and accounting
【多选题】
Which two configurations can prevent VLAN hopping attack from attackers at VLAN 10?___
A. using switchport trunk native vlan 10 command on trunk ports
B. enabling BPDU guard on all access ports
C. creating VLAN 99 and using switchport trunk native vlan 99 command on trunk ports
D. applying ACl between VLAN
E. using switchport mode access command on all host ports
F. using switchport nonegotiate command on dynamic desirable ports
【多选题】
What are two features of transparent firewall mode ___
A. It conceals the presence of the firewall from attackers
B. It allows some traffic that is blocked in routed mode
C. It enables the aSA to perform as a router.
D. It acts as a routed hop in the network.
E. It is configured by default
【多选题】
Which two models of A sa tend to be used in a data center?___
A. 5555X
B. 5585X
C. ASA service module
D. 5512X
E. 5540
F. 5520
【多选题】
Which two statements about hardware-based encrption are true?___
A. It is widely accessible
B. It is potentially easier to compromise than software-based encryption. It requires minimal configuration
C. It requires minimal configuration
D. It can be implemented without impacting performance
E. It is highly cost-effective
【多选题】
In which two modes can the Cisco We b Security appliance be de ployed?___
A. as a transparent proxy using the Secure Sockets Layer protocol
B. as a transparent proxy using the Web Cache Communication Protocol
C. explicit proxy mode
D. as a transparent proxy using the Hyper Text Transfer Protocol
E. explicit active mode
【单选题】
1.三相刀开关的图形符号与交流接触器的主触点符号是___。
A. 一样的
B. 可以互换
C. 有区别的
D. 没有区别