相关试题
【单选题】
交流放大电路中的能量来源于___。
A. 输入信号#
B. 三极管的放大作用#
C. 集电极电源#
D. 发射极电源
【单选题】
振荡器中振幅的稳定是由于___。
A. 电源电压限制了振幅#
B. 当振幅达到一定值后正反馈自动停止#
C. 晶体三极管的非线性#
D. 晶体二极管的线性
【单选题】
依靠触发电压的大小来实现翻转的触发器是___。
A. 集基耦合双稳态#
B. 射极耦合双稳态#
C. 单稳态#
D. 多稳态
【单选题】
在电感元件与电容器串联电路中，UL=10V 、UC=5V， 则总电压U=___V。
A. 5#
B. 10#
C. 15#
D. 20
【单选题】
二极管的“或”门电路中只要有一个输入端为高电位，则输出端为___电位。
【单选题】
晶体二极管反向电阻比较___。
A. 小#
B. 大#
C. 极小#
D. 不一定
【单选题】
三极管饱和导通时管压降约为___。
A. 0.7V#
B. 0.3V#
C. 1.4V#
D. 2V
【单选题】
电容器的___不能突变。
A. 感抗#
B. 电流#
C. 容抗#
D. 两端电压
【单选题】
我国规定的允许通过人体的电流值为___。
A. 20mA.s#
B. 30mA.s#
C. 36mA.s#
D. 38mA.s
【单选题】
当我们需要用到多个文件时，通常可以通过___来指定。
A. 文件名#
B. 通配符#
C. 文件夹#
D. 磁盘盘符
【单选题】
在目前的基带传输的矿井监控系统中，基带信号是___的型式。
A. 矩形脉冲#
B. 梯形脉冲#
C. 尖形脉冲#
D. 正弦波
【单选题】
传输线电感的大小与___成反比。
A. 交流电频率#
B. 线间距离#
C. 导线的导磁系数#
D. 导线直径
【单选题】
在"资源管理器"中，如果我们错误地删除了一个文件，可以通过___将其恢复。
A. 剪切按钮#
B. 撤消按钮#
C. 粘贴按钮#
D. 复制按钮
【单选题】
电容器储藏的电场能量与电压的平方成___。
A. 正比
B. 反比#
C. 没关系#
D. 指数
【单选题】
集成电路中常采用的级间耦合方式是___。
A. 直接耦合#
B. 阻容耦合#
C. 变压器耦合#
D. 磁场耦合
【单选题】
将十进制数（3.5）10转换成二进制数是___。
A. 11.11#
B. 10.11#
C. 11.10#
D. 11.01
【单选题】
当我们在电路中引入电压并联负反馈后，与基本放大器的输入、输出电阻相比，反馈放大器的输入、输出电阻的变化是___。 "
A. 输入电阻增大，输出电阻增大#
B. 输出电阻增大，输入电阻减小
C. 输入电阻减小，输出电阻增大#
D. 输入电阻减小或增大，输出电阻不变"
【单选题】
下列对场效应管的描述中，不正确的是___。
A. 场效应管具有输入电阻高，热稳定性好等优点#
B. 场效应管的两种主要类型是MOSFET和JFET#
C. 场效应管可应用于放大#
D. 场效应管可以构成共源、共栅、共漏这几种基本类型的放大
【单选题】
当稳压管在正常稳压工作时，其两端施加的外部电压的特点为___。
A. 反向偏置但不击穿#
B. 正向偏置但不击穿#
C. 反向偏置且被击穿#
D. 正向偏置且被击穿
【单选题】
在杂质半导体中，多数载流子的浓度主要取决于___。
A. 温度#
B. 杂质浓度#
C. 掺杂工艺的类型#
D. 湿度
【单选题】
在输入信号从极小到极大的一次变化过程中，迟滞比较器的输出会发生___次翻转。
【单选题】
在放大器中引入不同反馈可以改变放大器的不同性能。当我们希望达到稳定输出电流时应该引入___。
A. 电压正反馈#
B. 电压负反馈#
C. 电流负反馈#
D. 电流正反馈
【单选题】
三极管放大电路中，静态工作点的合理设置影响到电路能否正常工作及性能如何。共射电路中，若静态工作点设置过低，在输入信号增大时放大器会首先产生___。
A. 交越失真#
B. 放大失真#
C. 饱和失真#
D. 截止失真
【单选题】
___，一般有安全色、几何图形和图形符号构成，其目的时要引起人们对危害因素的注意，预防生产安全事故的发生。
A. 安全警示标志#
B. 危险标志#
C. 产品标志#
D. 特种标志
【单选题】
___，是指容易发生人员伤亡事故，对操作者本人、他人及周围设施的安全有重大危害的作业
A. 危险作业#
B. 特种作业#
C. 登高作业#
D. 特殊作业
【单选题】
在煤矿安全监管执法与决策系统中，不属于安全信息功能的是___ 。
A. 安全监控报警#
B. 人员管理报警#
C. 产量数据统计#
D. 产量监控报警
【单选题】
___工作面的防突措施包括预抽煤层瓦斯、排放钻孔、金属骨架、煤体固化、水力冲孔或其他经试验证明有效的措施。
A. 井巷揭煤#
B. 煤巷#
C. 岩巷#
D. 半煤岩巷
【单选题】
___方法不能减少巷道通风阻力
A. 采用梯形断面巷道#
B. 保持巷道连接部光滑#
C. 断面逐渐变化#
D. 清理巷道中不用的障碍物
【单选题】
___以下的煤层厚度叫薄煤层。
A. 1m#
B. 1.3m#
C. 1.5m#
D. 1.8m
【单选题】
___可用来扑灭电气设备火灾。
A. 水#
B. 砂子、岩粉#
C. 湿布#
D. 石头
【单选题】
___可采取超前钻孔预抽瓦斯、超前钻孔排放瓦斯、注水湿润煤体、松动爆破或其他经试验证实有效的措施。
A. 采煤工作面#
B. 煤巷掘进工作面#
C. 岩巷掘进工作面#
D. 掘进工作面
【单选题】
___必须对低压漏电保护进行1次跳闸试验。
A. 每班#
B. 每天
C. 经常#
D. 每周
【单选题】
___必须最后离开爆破地点，并必须在安全地点起爆。
A. 班组长#
B. 爆破工#
C. 瓦斯检查工#
D. 安检工
【单选题】
___发生火灾时，应进行区域性反风。
A. 进风井口#
B. 井底车场#
C. 进风大巷#
D. 工作面进风巷
【单选题】
___对事故隐患和安全生产违法行为，均有权向负有安全生产监督管理职责的部门报告或者举报。
A. 单位领导和群众#
B. 安全管理人员和技术人员#
C. 任何单位或者个人#
D. 工人
【单选题】
___应为接触职业病危害因素的从业人员提供符合要求的个体防护用品，并指导和督促其正确使用。
A. 煤矿企业#
B. 当地政府#
C. 国家#
D. 国有企业
【单选题】
___矿井必须装备安全监控系统、人员位置监测系统、有线调度通信系统。
A. 高瓦斯#
B. 所有#
C. 突出#
D. 低瓦斯
【单选题】
___要加大对安全生产工作的执法监督力度，保障劳动者的人身安全。
A. 国家#
B. 集体#
C. 企业
D. 部门
【单选题】
___是建立、健全安全生产责任制的根本目的。
A. 明确了确保安全生产#
B. 加强管理、建章立制、改善条件#
C. 改善安全生产条件和安全管理状况#
D. 依法从事生产经营
【单选题】
___是指在生产活动中，为消除能导致人身伤亡或造成设备、财产破坏以及危害环境的因素而制定的具体技术要求和实施程序的统一规定。
A. 安全法规#
B. 安全操作规程#
C. 规章制度#
D. 作业规程
推荐试题
【单选题】
Which information can you display by executing the show crypto ipsec sa command？___
A. ISAKMP SAs that are established between two peers
B. recent changes to the IP address of a peer router
C. proxy infor mation for the connection between two peers
D. IPsec SAs established between two peers
【单选题】
How can you prevent NAT rules from sending traffic to incorrect interfaces？___
A. Assign the output interface in the NAT statement
B. Add the no-proxy-arp command to the nat line.
C. Configure twice NAT instead o bject NAT. 5
D. Use packet-tracer rules to reroute misrouted NAT entries.
【单选题】
What term can be defined as the securing， control， and identification of digital data？___
A. cryptography
B. crypto key
C. cryptoanalysis
D. cryptology
【单选题】
Which feature in the dNS security module provide on and off network DNS protection？___
A. Data Loss Prevention
B. Umbrella
C. Real-time sandboxing
D. Layer-4 monitoring
【单选题】
Which a dverse consequence can occur on a network without BPDu guard ?___
A. The olde st switch can be elected as the root bridge
B. Unauthorized switches that are connected to the network can cause spanning-tree loops
C.
D. ouble tagging can cause the switches to experience CAM table overload.
【单选题】
What configuration is required for multitenancy ?___
A. shared infrastructure
B. multiple carriers
C. co-located resources
D. multiple separate zones
【单选题】
Why does ISE require its own certificate issued by a trusted CA？___
A. ISEs certificate allows guest devices to validate it as a trusted network device
B. It generates certificates for guest devices ba sed on its own certificate
C. It requests certificates for guest devices from the Ca server based on its own certificate.
D. ISE's certificate allows it to join the network security framework
【单选题】
which attack involves large numbers of ICMP packets with a spoofed source IP address？___
A. smurf attack
B. Teardrop attack
C. Nuke attack
D. SYN Flood attack
【单选题】
Which statement about interface and global access rules is true？___
A. Interface access rules are processed before global access rules.
B. Global access rules apply only to outbound traffic， but interface access rules can be applied in either direction
C. The implicit allow is proce ssed after both the global and interface access rules
D. If an interface access rule is applied， the global access rule is ignored
【单选题】
Which type of malicious software can create a back-door into a device or network？___
A. bot
B. worm
C. virus
D. Trojan
【单选题】
Which security term refers to the like lihood that a weakness will be exploited to cause damage to an asset？___
A. threat
B. risk
C. countermeasure
D. vulnerability
【单选题】
Which IPS detection method examines network traffic for preconfigured patterns？___
A. signature-based detection
B. honey-pot detection
C. anomaly-based detection
D. policy-based detection
【单选题】
What is an advantage of split tunneling ？___
A. It allows users with a VpN connection to a corporate network to access the internet with sending traffic across the cor porate network.
B. It allows users with a vpn connection to a corporate network to access the internet by using the vPN for security.
C. It protects traffic on the private network from users on the public network
D. It enables the VPN server to filter traffic more efficiently
【单选题】
Which IDS/IPS state misidentifies acceptable behavior as an attack ？___
A. false negative
B. true positive NEKA G
C. true negative
D. false positive
【单选题】
What is the maximum num ber of methods that a single method list can contain？___
【单选题】
Which command enables authentication at the oSPFv2 routing process level？___
A. ip ospf authentication message-digest
B. area 0 authentication message-digest
C. ip ospf message-digest-key 1 mds Cisco
D. area 0 authentication ipsec spi 500 md5 1234567890ABCDEF1234567890ABCDEF
【单选题】
Which type of firewall monitors a nd protects a specific system？___
A. firewall
B. application firewall
C. stateless firewall wvp
D. personal firewall
【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
【单选题】
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
D. MAC spoofing
【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
E. reflection
【多选题】
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
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
