相关试题
【判断题】
三相变压器的额定容量为额定电压与额定电流乘积的3倍。
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变压器既可以变换电压，又可以改变频率。
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"raQ9—5816／25型主变压器的铁芯为心式结构。
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TBQ9—5816／25型主变压器器身放在充满变压器油的油箱中。
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主变压器把从接触网上取得的25 kV高压电降为牵引电动机所适用的电压。
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变压器的空载试验只可以在低压绕组侧进行。
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变压器的励磁阻抗应该大，空载损耗和空载电流小。
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变压器的空载试验是将副边绕组处于短路状态。
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变压器的变比为原边绕组电势与副边绕组电势之比。
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从空载到满载，变压器的磁滞损耗和涡流损耗是基本上不变的。
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变压器的原边和副边绕组之间没有磁的联系，只有电的联系。
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电动机启动用的自耦变压器其抽头分别是60％、80％。
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电力机车电气原理图是用来表示电气协作原理的。
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电路的通断和转换通过电器中的执行部件，主要是靠其触头来实现。
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电力机车上主按键开关钥匙只有在辅助开关处于断开位时才能插入或取出。
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交一直型电力机车采用交流牵引电动机做牵引动力。
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对于电力机车上许可触及的电气仪表和设备均需可靠接地。
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机车主电路、辅电路、控制电路之间无任何电的联系。
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机车牵引力和运行速度的乘积，就是机车的功率。
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任何一种机车，它的功率是一定的，叫做标称功率。
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电器是应电能的运用而产生的，所以电机和一般的负载属于电器的范畴。
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电器工作时，发热和散热不同时存在于电器发热过程中。
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电磁驱动装置是把电能转换为磁能的机构。
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对电网来说三相异步电动机是一个电感负载。
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电器工作时，发热和散热不同时存在于电器发热过程中。
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电弧属于气体放电的一种形式，气体放电分为自持放电与非自持放电两类。
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电器触头驱动装置有三种：电驱动、手动、磁驱动。
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触头对电器的工作性能、总体结构、尺寸有着决定性的影响。
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【填空题】
46.天基武器系统主要指攻击对方航天器用的卫星和卫星平台，包括 ___ 、 ___和___ 等。
【填空题】
47.中国人民解放军海军成立于___年。
【填空题】
48.新概念武器主要有 ___ 、___、 ___ 、 ___ 、___ 等。
【填空题】
49.核武器具有____、冲击波、____ ___、核电磁脉冲和放射性沾染等五种杀伤破坏因素。
【填空题】
50.精确制导技术是指采用高技术直接命中概率超过___以上的武器。
【单选题】
What is an example of social engineering？___
A. gaining access to a computer by observing the user login credentials
B. gaining access to a build through an unguarded entrance
C. gaining access to a server by using a USB stick
D. gaining access to a server room by posing as local IT
【单选题】
Which type of Layer 2 attack enables the attacker to intercept traffic that is intended for one specific recipient？___
A. BPDU attack
B. DHCP starvation I LAB
C. MAC address spoofing
D. CAM table overflow
【单选题】
Which about nested policy maps in a zone-based firewall is true ?___
A. They are limited to two leve ls in a hierarchical policy
B. Parent policies are previously defined policies that are defined by using the service policy command
C. A child policy is a new policy that uses a pre-existing policy.
D. A child policy is a new that uses a pre-existing policy
【单选题】
In which configuration do you configure the ip ospf authentication key 1 command？___
A. routing process
B. interface
C. privileged
D. global
【单选题】
Which statement about command authorization and security contexts is true？___
A. If command authorization is configured， it must be enabled on all contexts.
B. The change to command invokes a new context session with the credentials of the currently
C. AAA settings are applied on a per-context basis
D. The enable. 15 user ang admins with chang to permission ha e dfferent command authorization levels pertontext
【单选题】
Which command do you enter to enable authentication for OSPF on an interface？___
A. router（config-if）#ip ospf message-digest-key 1 md5 CIS COPASS
B. router（config-if）#ip ospf authentication message-digest
C. router（config-if）#ip ospf authentication-key CISCOPASS
D. router（config-if）#area 0 authentication message-digest
【单选题】
What feature defines a campus area network？___
A. It has a single geographic location
B. It lacks external connectivity.
C. It has a limited number of segments.
D. It has limited or restricted Internet access
【单选题】
Which type of attack most commonly involves a direct attack on a network？___
A. :phishing
B. Trojan horse
C. denial of service
D. social engineering
【单选题】
What information does the key length provide in an encryption algorithm?___
A. the cipher block size
B. the hash bloc k size
C. the number of permutations
D. the packet size
【单选题】
How do you verify TaCACS+ connectivity to a device？___
A. You successfully log in to the device by using the local credentials
B. You connect via console port and receive the login prompt.
C. You connect to the device using SSH and receive the login prompt.
D. You successfully log in to the device by using ACS credentials
【单选题】
Which term best describes the concept of preventing the modification of data in transit and in storage？___
A. availability
B. confidentially
C. fidelity
D. integrity
【单选题】
Which loS command is used to define the authentication key for ntp？___
A. switch（config ）#ntp authentication-key 1 mds Clcs
B. switch（config ）#ntp authenticate
C. switch（config）#ntp trusted-key 1
D. switch（config）#ntp source 192.168.0.1
【单选题】
What is true about the cisco lOS Resilient Configuration feature ?___
A. The feature can be disabled through a remote session
B. There is additional space required to secure the primary cisco lOS image file.
C. The feature automatically detects image or configuration version mismatch.
D. Remote storage is used for securing files
【单选题】
When is the default deny all policy an exception in zone-based firewalls？___
A. when traffic terminates on the router via the self zone
B. when traffic traverses two interfaces in different zones
C. when traffic traverses two interfaces in the same zone
D. when traffic sources from the router via the self zone
【单选题】
.If an access port is assigned as an isolated port in a PVLAN， which network ports can it communicate with？___
A. promiscuous ports in the same PLVAN
B. isolated ports in the same PVLAN
C. all ports in the same PAVLAN at ILAR
D. all ports in the adjacent PVLAN
【单选题】
Which IPSEC mode is used to encypt traffic directly between a client and a server VPN endpoint？___
A. quick mode
B. transport mode
C. aggressive mode
D. tunnel mode
【单选题】
Which command do you enter to verify that a vpn connection is established between two endpoints and that the connection is passing traffic？ ___
A. Firewall#sh crypto session
B. Firewall#debug crypto isakmp
C. Firewall#tsh crypto ipsec sa
D. Firewall#sh crypto isakmp sa
【单选题】
which type of Pvlan port allows communication from all port types？___
A. isolated
B. in -line
C. community
D. promiscuous
【单选题】
Which command do you enter to configure your firewall to conceal internal addresses？___
A. no ip directed-broadcast
B. no ip logging facility
C. no proxy-arp
D. no ip inspect audit-trial
E. no ip inspect
F. route
【单选题】
Which feature defines a campus area network？ ___
A. It has a limited number of segments.
B. It has limited or restricted Internet access
C. It lacks ex1ternal connectivity.
D. It has a single geographic location
【单选题】
What technology can you use to provide data confidentiality data integrity and data origin authentication on your network？___
A. IPSec
B. Certificate Authority
C. IKE
D. Data
E. ncryption Standards
【单选题】
which standard is a hybrid protocol that uses oakley and skerne ke y exchanges is an ISAKMP framework？___
【单选题】
What is the actual los privilege level of User Exec mode？___
【单选题】
What is the effect of the asa command crypto isakmp nat-traversal？___
A. It opens port 500 only on the out side interface
B. It opens port 500 only on the inside interface
C. It opens port 4500 on all interfaces that are IPSec enabled
D. It opens port 4500 only on the out side interfac
【单选题】
Which Fire POWER preproce ssor engine is used to prevent SYN attacks？___
A. Inline normalization
B. IP Defragmentation
C. Ports can
D. etection
【单选题】
Which NAT type allows objects or groups to reference an IP address ？___
A. identity NAt
B. static NAT
C. dynamic
D. dynamic NAT
【单选题】
Which Auto NAT policies are processed first？___
A. Dynamic NAT with longest prefix
B. Dynamic NAT with shortest prefix
C. static NAT with longest prefix
D. static NAT with shortest prefix
【单选题】
Which feature allows a dynamic Pat pool to se lect the next address in the pat pool instead of the next port of an existing address？___
A. next IP
B. round robin
C. dynamic rotation
D. NAT address rotation
【单选题】
Which IPS detection method can you use to detect attacks that are based on the attackers IP address？___
A. anomally-based
B. policy-based
C. signature-based
D. reputation-based
【单选题】
Which type of encryption technology has the broadest platform support？___
A. software
B. middleware
C. file-level
D. hardware
【单选题】
Which type of address translation supports the initiation of comm unications bidirectionally ？___
A. multi-session PAT
B. dynamic NAT
C. dynamic PAT
D. static NAT
【单选题】
Which label is given to a person who uses existing computer scripts to hack into computers while lacking the expertise to write the own？___
A. script kiddy
B. white hat hacker
C. hacktivist
D. phreaker
【单选题】
What is the primary purpose of a defined rule in an IPS？___
A. to configure an event action that takes place when a signature is triggered
B. to define a set of actions that occur when a specific user logs in to the system
C. to configure an event action that is pre-defined by the system administrator
D. to detect internal attacks
【单选题】
Which option is the default valuce for the Diffie- Hell man group when configuring a site-to-site VPn on an asa device ？___
A. Group 1
B. Group 2
C. Group 5
D. Group 7
【单选题】
Which feature filters CoPP packets?___
A. access control lists
B. class maps
C. policy maps
D. route maps
