【单选题】
质点在电磁波作用下产生散射时,散射能量在空间的分布是___。
A. 均匀的
B. 不均匀的
C. 仅前后向不同
D. 不好比较
查看试卷,进入试卷练习
微信扫一扫,开始刷题
答案
B
解析
暂无解析
相关试题
【单选题】
通常,冰雹云的雷达回波比一般积雨云强,是由于冰雹云比积雨云的___。
A. 云中粒子的尺度大
B. 对流强
C. 水平尺度大
D. 垂直尺度高
【单选题】
雷达定量测量降水的误差主要是因为___。
A. 雷达难于精确测量参数
B. 计算方法精度低
C. z-I关系不稳定
D. 单部雷达探测范围有限
【单选题】
强度不变的同一积雨云从雷达站的315°方向200kM处向东南方向移动,在雷达上看起来积雨云回波的强度愈来愈强,这是因为___。
A. 积雨云高度愈来愈高
B. 积雨云尺度愈来愈大
C. 大气的衰减愈来愈小
D. 距离衰减愈来愈小
【单选题】
通常,超折射回波的本质是___。
A. 降水回波
B. 地物回波
C. 鸟的回波
D. 其它气象回波
【单选题】
在PPI上,典型的超级单体几乎都有___。
A. 强对流回波
B. 钩状回波
C. 指状回波
D. “V”形缺口
【单选题】
梅雨锋暴雨回波中,在RHI上,强回波位于O℃等温线的___。
A. 上下
B. 上部
C. 下部
D. 大部分在下部
【单选题】
在多普勒速度图上,某一点所谓零速度是指该点处的实际风向___。
A. 垂直于该点的径向
B. 平行于该点的径向
C. 与该点的径向成450 交角
D. 与该点的径向成1350交角
【单选题】
圆形的中气旋流场,在多普勒速度图上表示为有___。
A. 一个风速极大值
B. 强大的正风速区
C. 强大的负风速区
D. 一对对称的正负速度中心
【单选题】
雷达探测脉冲在大气中传播,遇到降水粒子产生雷达回波是___。
A. 粒子对电磁波的反射
B. 粒子对电磁波的折射
C. 粒子对电磁波的散射
D. 粒子对电磁波的后向散射。
【单选题】
大水滴的后向散射截面总比小水滴的后向散射截面___。
A. 大
B. 小
C. 稍大
D. 大很多。
【单选题】
大冰雹的后向散射截面随着降落过程其表面开始融化而___。
A. 增大
B. 减小
C. 不变
D. 大减
【单选题】
以低仰角探测到在雷达站西北方位300公里处有一块30—35dbZ回波区,可是当时雷达站及其周围地面观测均无降水(雷达站天线高度为200米,以0°仰角探测),这块回波可能是___。
A. 地物回波
B. 层状云的云顶回波
C. 发展中积状云的中部回波
D. 层状云的零度层亮带
【单选题】
国家气象中心高分辨率有限区域分析预报系统的英文缩写是___。
A. HIRLAM
B. MICAPS
C. HLAFS
D. HILAFS
【单选题】
GCOS 指全球___观测系统。
A. 地理
B. 气候
C. 天气
D. 资源
【单选题】
通过业务技术体制改革要建立资源高度共享、相互支撑、协调发展的综合观测、预报预测、公共服务、信息与技术保障、___和教育培训等体系。
A. 宏观调控
B. 人才保障
C. 技术改革
D. 科技创新
【单选题】
健全综合观测体系必需开展“三站四网”建设。“三站”是指:国家气候观象台、国家气象观测站、___天气观测站。
A. 国家
B. 省级
C. 区域
D. 中尺度
【单选题】
预报雨夹雪,实况雨夹雪,降水分级检验评定为___。
A. 小雨正确
B. 小雪正确
C. 小雨或小雪都正确
D. 小雨或小雪都不正确
【多选题】
同时出现或者预报可能同时出现多种气象灾害时,可以______或_______。___
A. 按照最严重的一种灾害发布预警信号
B. 按照对应的标准同时发布多种预警信号
C. 挂一种预警信号的标志,但提示语中可包括多种气象灾害的内容
D. 按固定时间间隔依次发布各种气象灾害的预警信号
【多选题】
台风最大风速位于_______。___
A. 台风眼区
B. 台风涡旋区
C. 台风大风区
【多选题】
导致降水估计偏差的因素除了不适当的______外,还包括雷达硬件定标误差、湿的天线罩、______、远距离处雷达波束从降水系统______穿过、超折射地物杂波和______的影响等。___
A. 上面
B. 冰雹
C. 亮带
D. Z-R关系
E. 降水估计方法
F. 下面
【多选题】
风暴动力结构及风暴潜在的影响力很大程度上取决于环境的______、风的______和______的垂直分布三个因子。___
A. 湿度
B. 温度
C. 热力不稳定(浮力)
D. 水汽
E. 垂直切变
【多选题】
位涡守恒的条件是_____、_______。___
A. 正压大气
B. 斜压大气
C. 无水平辐合辐散
D. 大气不可压缩
【多选题】
电磁波在真空中是沿直线传播的,而在大气中由于______分布的不均匀性,就会产生______,使电磁波的传播路径发生弯曲。暖干盖的大气层结,最有可能发生的是______。___
A. 折射指数
B. 折射
C. 温度层结
D. 负折射
E. 超折射
【多选题】
日本传真图上的高压中心是用字母___标注。
A. C
B. G
C. H
D. N
【多选题】
当假相当位温随高度增加呈负增长时,表示大气层结趋于___。
A. 稳定
B. 不稳定
C. 不确定
【多选题】
沙氏指数大于零,表示大气层结___。
A. 稳定
B. 不稳定
C. 不一定
【多选题】
强台风标准是:近地面台风中心附近最大平均风力为___。
A. 12-13级
B. 14-15级
C. 16级或以上
【多选题】
T-lnP图上,状态曲线左侧和层结曲线右侧的区域为___。
A. 正的不稳定能量区
B. 负的不稳定能量区
C. 干区
【多选题】
大尺度天气系统的特征包括___。
A. 准水平
B. 准静力平衡
C. 准地转
D. 自由大气
E. 理想气体。
【多选题】
大气环流形成和维持的最主要的因子是___。
A. 地球自转
B. 太阳辐射
C. 地面摩擦
D. 地球表面不均匀
E. 自由大气。
【多选题】
暴雨形成条件___。
A. 充分的水汽条件;
B. 强烈的上升运行 ;
C. 较长的持续时间;
D. 较强的冷空气活动 。
【多选题】
根据涡度方程,天气尺度系统变化趋势的定性规则是___。
A. 暖平流使高层反气旋性环流减弱, 低层反气旋环流发展
B. 暖平流使高层反气旋性环流加强,低层气旋环流发展
C. 暖平流使高层反气旋性环流加强, 低层反气旋环流减弱
D. 冷平流使高层气旋性环流加强, 低层反气旋环流发展
【多选题】
北半球500hPa平均图上的低槽有“冬三夏四”的特征,所谓“冬三”指的是___。
A. 东亚大槽
B. 北美大槽
C. 欧洲浅槽
D. 贝加尔湖西部槽
【多选题】
西风带长波的移动速度与许多因素有关。当___时,波动移动较快,反之,移动较慢。
A. 地转涡度平流较大
B. 波长较短
C. 纬度较高
D. 西风较强
【多选题】
由于地形和摩擦的影响,___移近大山脉时,在山前减弱,山后重新发展。
A. 高空槽
B. 高空脊
C. 地面气旋
D. 地面反气旋
【多选题】
影响我国的寒潮冷空气源地主要有___。
A. 新地岛以西洋面
B. 东西伯利亚
C. 冰岛以南洋面
D. 西西伯利亚
E. 新地岛以东洋面
F. 白令海峡
【多选题】
我国寒潮的中短期天气形势可归纳为___。
A. 小槽发展型
B. 横槽型
C. 低槽东移型
D. 阻高崩溃型
【多选题】
基本力是大气与地球或大气之间的相互作用而产生的真实力,它们的存在与参考系无关。基本力包括___。
A. 地心引力
B. 气压梯度力
C. 摩擦力
D. 地转偏向力
【多选题】
低空急流对暴雨形成的作用有___。
A. 暖湿空气的输送,产生位势不稳定层结
B. 造成辐合,产生强上升运动
C. 急流区左前方形成正切变涡度区
D. 加强垂直风切变
【多选题】
一般雷暴单体的生命史大致可分为___。
A. 发展阶段
B. 成熟阶段
C. 锢囚阶段
D. 消亡阶段
推荐试题
【多选题】
Which two characteristics of an application layer firewall are true?___
A. provides stateful firewal functionality
B. has low processor usage
C. provides protection for multiple applications
D. provides rever se proxy services
E. is immune to URL manipulation
【多选题】
Which two devices are components of the BYOD architectural framework?___
A. Nexus 7010 switch
B. Cisco 3945 Router
C. Identify Services Engine
D. Wireless Access oints
E. Prime Infrastructure
【多选题】
Which two actions can a zone based firewall take when looking at traffic? ___
A. forward
B. inspect
C. drop
D. broadcast
E. filter
【多选题】
n which two situations should you use in-band management?___
A. when management applications need concurrent access to the device
B. when you require administrator access from multiple locations
C. when a network device fails to forward packets
D. when you require ROMMON access
E. when the control plane fails to respond
【多选题】
What are two ways to prevent eavesdropping when you perform device management tasks?___
A. Use an SSH connection.
B. Use SNMPv3
C. Use out-of-band management
D. Use SNMP
E. Use in-band management
【多选题】
Which two features are commonly used CoPP and CPPr to protect the control plane? ___
A. QoS
B. traffic classification
C. access lists
D. policy maps
E. class maps
F. Cisco Express Forwarding
【多选题】
Which four tunne ling prot ocols are enabled in the Dfit GrpPolicy group policy ?___
A. Clientless SSL VPN
B. SSL VPN Client
C. PPTP
D. L2TP/IPsec
E. IPsec IKEv1
F. IPsec IKEv2
【多选题】
Which two statements regarding the aSA VPN configurations are correct?___
A. The asa has a certificate issued by an external certificate authority associated to the ASDM TrustPoint1
B. The Default WEBVPNGroup Connection Profile is using the aaa with RADIUS server method
C. The Inside-srvbook mark references the https://192.168.1.2url
D. Only Clientless SSL VPN access is allowed with the Sales group policy
E. Any Connect, IPSec IKEv1, and IPSec IKEv2 VPN access is enabled on the outside interface
F. The Inside -SRV bookmark has not been applied to the Sales group policy
【多选题】
Which three ESP fields can be encrypted during transmission?___
A. Security Parameter Index
B. Sequence Number
C. MAC Address
D. Padding
E. Pad length
F. Next Header
【多选题】
.Which three statements de scribe DHCP spoofing attacks?___
A. They can modify traffic in transit.
B. They are used to perform man- in-the-middle attacks
C. They use ARP poisoning
D. They can access most network devices
E. They protect the ide ntity of the attacker by masking the DHCP address.
F. They are can physically modify the network gateway.
【多选题】
Which statement about the communication between interfaces on the same security level is true?___
A. Interfaces on the same security level require additional configuration to permit interinterface communication
B. Configuring interfaces on the same security level can cause asymmetric routing
C. All traffic is allowed by default between interfaces on the same security level
D. You can configure only one interface on a n individual security level
【多选题】
In which two situations should you use in band management? ___
A. when the control plane fails to respond
B. when you require administrator access from multiple locations
C. when you require ROMMON access.
D. where a network device fails to forward packets
E. when multiple ma nagement applications need concument access to the device.
【多选题】
Which two features are supported in a VRF-aware softwar infrastructure before VRF-lite?___
A. multicast
B. fair queuing
C. WCCP
D.
E. IGRP
【多选题】
.Which loS command do you enter to test authentication again a AAA server?___
A. dialer aaa suffix <suffix> password <password>
B. ppp authentication chap pap test
C. test aaa-server authentication dialer group user name <user> password <password>
D. aaa authentication enable default test group tacases
【多选题】
Which two statements about the self zone on a cisco Xone based policy firewall are true?___
A. Multiple interfaces can be assigned to the self zone
B. it supports stateful inspections for multicast traffic
C. zone pairs that include the self zone apply to traffic transiting the device.
D. it can be either the source zone or the destination zone
E. traffic entering the self zone must match a rule
【多选题】
Which type of attack can exploit design flaws in the implementation of an application without ?___
A. DHCP starvation attacks
B. low-rate dos attacks
C. application DDos flood attacks
D. application DDoS flood attacks
E. volume-based DDoS attacks
【单选题】
Which type of firewall can server as the interme diary between a client and a server ?___
A. Stateless firewall
B. application firewall
C. proxy firewall
D. personal firewall
【单选题】
What is the highest security level that can be configured for an interface on an ASA?___
A. 0
B. 50
C. 10
D. 200
【单选题】
Which term refers to the electromagnetic interference that can radiate from network cables?___
A. Gaussian distributions
B. Doppler waves
C. emanations
D. multimode distortion
【单选题】
How does a zone pair handle traffic if the policy de fination of the zone pair is missing?___
A. It inspects all traffic.
B. It drops all traffic.
C. It permits all traffic wihtout logging
D. It permits and logs all traffic
【单选题】
default how does a zone based firewall handle traffic to add from the self zone?___
A. It permits all traffic without inspection
B. It inspects all traffic to determine how it is handled
C. It permits all traffic after inspection
D. It frops all traffic
【单选题】
Which command should beused to ena ble AAA Authentication to determine if a user can access the privilege command level?___
A. aaa authentication enable local
B. aaa authentication enable level=
C. aaa authentication enable method de fault
D. aaa authentication enable defa ult local
【单选题】
On an ASA, the policy indicates that traffic should not be translated is often referred to as which of the following?___
A. NAT zero
B. NAT forward
C. NAT nul
D. NAT allow
【单选题】
Which protocol offers data Integrity encryption, authentication, and anti-replay functions for IPSec VPN?___
A. ESP protocol
B. IKEv3 Protocol
C. AH protoco
D. IKEv1 Protocol
【单选题】
Which component offers a variety of security Solution, including firwall, IF Antivirus and antiphishing features?___
A. Cisco loS router
B. Cisco ASA 5500 Ser ies security appliance
C. Cisco ASA 5500 X series Next Gen Security appliance
D. Cisco 4200 series IPS appliance
【单选题】
Refer to the exhibit, A Network Secur ity administrator check the ASa firewall NAT policy table rith show nat command, which statement is fails?___
A. There are only reverse translation matches for the REAL SERvER object
B. First policy in the Section 1 is a dynamic nat entry defined in the object configuration
C. NAT policy in section 2 is static entry de fined in the object configuration
D. Translation in Section 3 used when a connection does not matches any entries in first two sections
【单选题】
What is true of an aSa in transparent mode ?___
A. It supports OSPF
B. It requires an IP address for each interface
C. It requires a management IP address
D. It allows the use of dynamic NaT
【单选题】
What is the effect of the ip scp server enable command?___
A. It references an access list that allows specific SCP servers
B. It allows the router to initiate requests to an SCP server
C. It allows the router to become an SCP server
D. It adds SCP to the list of allowed copy functions
【单选题】
How can you mitigate attacks in which the attacker attaches more than one vLan tag to a packet?___
A. Assign an access VLAN to every active port on the switch
B. Disable Ether Channel on the switch
C. Explicitly identity each VLAN allowed across the trunk
D.
E. nable transparent VTP on the switch
【单选题】
Which technology can you implement to centrally mitigate potential threats when users on your network download files that might be malicious?___
A. Enable file-reputation services to inspect all files that traverse the company network and block files with low reputation scores
B. Verify that the compa ny IpS blocks all known malicious website
C. Verity that antivirus software is installed and up to date for all users on your network
D. Implement URL filtering on the perimeter firewall
【单选题】
What is the most common implementation of PaT in a standard networked environment?___
A. configuring multiple external hosts to join the self zo ne and to communicate with one another
B. configuring multiple internal hosts to communicate outside of the network using the outside interface IP address
C. configuring multiple internal hosts to communicate outside of the network by using the inside interface IP address
D. configuring an any any rule to enable external hosts to communicate inside the network
【单选题】
Which component of a bYod architecture provides aAa services for endpoint access ?___
A. Integrated Services Router
B. access point
C. ASA
D. Identity Services
E. ngine
【单选题】
You are configuring a NAT rule on a Cisco ASA ,Which description of a mapped interface is true?___
A. It is mandatory for all firewall modes
B. It is optional in routed mode
C. It is optional in transparent mode
D. It is mandatory for ide ntity NAT only
【单选题】
Which description of the use of a private key is true ?___
A. The sender signs a message using the receivers private key
B. The sender signs a message using their private key
C. The sender encrypts a message using the receivers private key
D. The receiver decrypts a n15ssage using the sender's private key
【单选题】
Which mechanism does the FireAMP Connector use to avoid conflicts with other security applications such as antivirus products ?___
A. Virtualization
B. Containers
C. Sandboxing
D.
E. xclusions
【单选题】
Which network to pology de scribes multiple LANS in a gec? ___
A. SOHO
B. MAN
C. pan
D. CAN
【单选题】
Which statement represents a difference between an access list on an aSa versus an access list on a router?___
A. The asa does not support number access lists
B. The aSa does not support standard access list
C. The asa does not ever use a wildcard mask
D. The asa does not support extended access lists
【单选题】
Which command do you enter to verify the status and settings of an iKE Phase 1 tunnel?___
A. show crypto ipsec as output
B. show crypto isakmp
C. show crypto isakmp policy
D. show crypto ipsec transform
【单选题】
Which feature can help a router or switch maintain packet forwarding and protocol states despite an attack or heavy traffic load on the router or switch?___
A. service Policy
B. Control Plane Policing
C. Policy Map
D. Cisco
E. xpress
F. orwarding
【单选题】
Which STP feature can prevent an attacker from becoming the root bridge by immediately shutting down the interface when it receives a BPDU?___
A. root guard
B. Port Fast
C. BPDU guard
D. BPDU filtering