【判断题】
用一个恒定电流I是和一个电导G0并联表示一个电源,这种方式表示的电源称电流源。若Go=0则称为理想电流源
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在实际工程应用中,弧垂的大小必须经过现场计算得到
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安装变压器与建筑物要保持足够距离,建筑物屋檐雨水不得落到变压器上
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供电公司对电力客户的供电电压,应依据国家的有关政策和规定以及当地供电条件等因素,进行技术经济比较,自行确定
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终端使用交流单相或三相供电。三相供电时,电源出现断相故障,即三相三线供电时断两相电压,三相四线供电时断一相电压的条件下,交流电源能维持终端正常工作
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变压器铁损的大小与电源电压的平方成反比
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在由电感线圈组成的交流电路中,若其电阻可忽略不计,便可近似地看成是纯电感电路
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在巡视时,应注意铁横担是否锈蚀、变形、松动或严重歪斜
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对于长期空载运行的变压器,应切断变压器的电源
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有载调压变压器并联运行时,其调压操作应轮流逐级或同步进行
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在电网额定电压下,对电力电容器组的冲击合闸试验应进行10次,熔断器应不熔断
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放紧线时,应按导地线的规格及每相导线的根数和荷重来选用放线滑车
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电流互感器一次绕组匝数多,二次绕组匝数少
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智能表如果有失压报警或提示,不必抄录失压记录
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多根电力电缆并列敷设时,电缆接头要并排装接,以方便检修
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装设同杆架设的多层电力线路接地线,应先装设低压、后装设高压,先装设下层、后装设上层,先装设近侧、后装设远侧。拆除接地线的顺序与此相反
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经电流互感器的三相四线电能表,一只电流互感器极性反接,则电能表会走慢1/3
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基本电费可按变压器容量计算,也可按最大需量计算,具体选择办法,由供电企业报装部门确定
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在铁心内部产生的环流称为涡流,涡流所消耗的电功率,称为涡流损耗
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反映电感线圈自身功能的参数叫电感,用符号L表示
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特殊性巡视为查明线路发生故障的地点和原因而进行的巡视
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与10kV开关站相关的线路跳闸后,运行人员应做故障特巡检查
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高压柱上负荷开关由隔离开关和灭弧室组成,它可以切断较大的短路电流
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电容器加装放电装置,是为了在电容器停电后,尽快地放尽电容器的残余电荷
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电流互感器二次侧具有多组绕组,若仅使用一组绕组,则为保证计量的准确性,其余绕组应保持开路状态
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对执行分时峰谷电价的用户,大力推广使用蓄热式电锅炉(电热水器)和冰蓄冷集中型电力空调器,对改善系统负荷曲线,用户减少电费支出都有好处
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由于铝导线比铜导线导电性能好,故使用广泛
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【单选题】
Which security term refers to the like lihood that a weakness will be exploited to cause damage to an asset?___
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Which IPS detection method examines network traffic for preconfigured patterns?___
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What is an advantage of split tunneling ?___
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What is the maximum num ber of methods that a single method list can contain?___
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Which command enables authentication at the oSPFv2 routing process level?___
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Which type of firewall monitors a nd protects a specific system?___
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On an ASA, which maps are used to identify traffic?___
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A. whaling
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What is the minimum Cisco lOS version that supports zone-based firewalls?___
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In which type of attack does an attacker overwrite an entry in the CAM table to divert traffic destined to a legitimate host?___
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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
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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
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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
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What are two advanced features of the Cisco AMp solution for endpoints ___
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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
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What are two challenges of using a network-based IPS? ___
A. It is unable to determine whether a detected attack was successful
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What are two default be haviors of the traffic on a zone-based firewall?___
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Which two advantages does the on-premise model for MDM deployment have over the cloud-based model?___
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B. The on-premise model is more scalable than the cloud-based model
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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
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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
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【多选题】
Which two are considered basic security principles?___
A. Accountability
B. Redundancy
C. High Availabilit
D. Integrity
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Which two roles of the Cisco WSA are true?___
A. IPS
B. firewall
C. antispam
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Which next-generation encryption algorithm supports four variants?___
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What aims to remove the abil ity to deny an action?___
A. Non-Repudiation
B. Accountability
C. Integrity
D. Deniability
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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
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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?___
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What does the dh group refer to?___
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Which path do you follow to enable aaa through the SDM ?___
A. Configure Tasks > AAA
B. Configure > Addition Authentication > AAA
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E. Configure Authentication > AAA
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which technology cloud be used on top of an MPLS VPN to add confidentiality ?___
A. IPsec
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Which term is most closely aligned with the basic purpose of a SIEM solution? ___
A. Non-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?___
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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?___
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Which command enables port security to use sticky MAC addresses on a switch?___
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C. switchport port-security violation protect
D. switchport port-security
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When you edit an IPS subsignature, what is the effect on the parent signature and the family of subsignatures?___
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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
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Which type of mechanism does Cisco FirePOWER de ploy to protect ag detected moving across other networks?___
A. antivirus scanning
B. policy-based
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D. signature-based
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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
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Which type of firewall can perform deep packet inspection?___
A. packet-filtering firewall
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C. application firewall
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What is the main purpose of Control Plane Policing?___
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D. to maintain the policy map