undulating-70

英语解说词丹霞山

智能建筑中的电源质量要求是非常重要的，了解电源对于建筑的重要性，才能更好的理解其质量代表的意思，每个细节都很关键。中达咨询就智能建筑中的电源质量要求和大家说明一下。

随着国际信息潮流冲击和微电子科技的沸腾，加上通讯、计算机及自动控制技术日新月异，使得建筑开始走向高品质、高功能领域，形成一种新的建筑形式――智能建筑（Inetlligent Buildings）。由于在智能建筑中运用了许多计算机和微电子设备，对其供电电源的质量提供了新的要求。因为电源品质的好坏，将直接影响智能建筑中设备的运行稳定性和可靠性，甚至导致重大人身、设备事故和造成巨大的经济损失。这种影响不仅来自供电电源的电压、频率及电流等基本要素是否满足用电设备的要求，而且也来自所提供的供电电源的电网质量。

由于电子计算机、微处理器以及其他电子仪器设备普遍存在着绝缘强度低、对供电电源的质量要求高、过电压耐受能力差的弱点，使得这些高灵敏的电子系统在运行时，经常出现程序运行错误、数据错误、时间错误、死机、无故重新启动甚至造成用电设备的永久性损坏，给人们日常生活造成巨大损失。为此，在智能建筑中，研究其供电电源质量，实施有效的防护措施，已是必然的趋势，而且受到世界各国普遍关注。

1、电源质量的技术指标

衡量电源质量的技术指标主要包括：电压波动、频率波动、谐波和三相不平衡等。众所周知，供电电源质量会受到多种因素的影响，如负荷的变化、大量非线性负载的使用、高次谐波的影响、功率因数补偿电容的投入和切断、雷电和人为故障、公共设施（如电动机、电梯等）等都会影响电源的品质，从而降低供电电源的质量。

1.1 电压波动（Undulating voltage）

理想电源电压正弦波的波形是连续、光滑、没有畸变的，其幅值和频率是稳定的。当负荷发生变化时，负荷出现较大的增加时，特别是附近有大型设备处于启动时，使得供电电源正弦波的幅值受到影响，产生低电压。当供电电源电压波动超过允许范围时，就会使计算机和精密的电子设备运算出现错误，甚至会使计算机的停电检测电路误认为停电，而发生停电处理信号，影响计算机的正常工作。一般计算机允许电压波动范围为：AC 380V、220V±5％。计算机在电压降低至额定电压的70％时，计算机就视为中断。为此，《电子计算机机房设计规范》GB 50174－93（以下简称《规范》）对电压波动明确规定，将电压波动分为A、B、C三级。

1.2 频率波动（Undulating frequency）

供电电源频率波动主要由于电网超负荷运行而引起发电机转速的变化所致。而计算机的外部设备大多采用同步电动机，一般计算机频率允许波动范围为50Hz±1%.当供电电源频率波动超过允许范围时，会使计算机信息存储的频率发生变化而产生错误，甚至会产生信息丢失等。

1.3 波动失真（Waveforn distortion）

产生电源电压波形失真的主要原因是由于电网中非线性负载，特别是一些大功率的可控整流装置的存在会对供电电源的电压波形产生烃，还会使计算机的相对控制部分产生不利的影响；这种波形畸变，还会使计算机直流电源回路中的滤波电容上的电流明显增大，电容器发热；还由于锯状波形的出现，会使计算机的停电检测电路误认为停电，而发出停电处理信号，影响计算机的正常工作。衡量波形失真的技术指标是波形失真率（Waveform distortion rate），即用电设备输入端交流电压所有高次谐波之和与基波有效值之比的百分数。

1.4 瞬变浪涌和瞬变下跌

瞬变浪涌（Transient voltage surge）是指正弦波在工频一周或几周范围内，电源电压正弦波幅值快速增加。瞬变浪涌一般用最大瞬变率表示。瞬变下跌（Tran－sition voltage fall），又称凹口，它是指正弦波在工频一周或几周范围内，电源电压正弦波幅值快速下降。瞬变下跌一般用最大瞬变下跌率表示。瞬变浪涌和瞬变下跌，瞬间内电压幅值快速增加或减小会对计算机系统形成干扰，导致其运算错误或者破坏存储的数据和程序。目前，国内未对瞬变大瞬变率：（半周或更长）≤20％；恢复过程中降至15％以内，为50ms；然后降至6％以内，为0.5s.允许最大瞬变下跌率：（半周或更长）≤30％；恢复到－20％以内，为50ms；恢复到－13.3％以内，为0.5s。

1.5 瞬变脉冲（Transient voltage pulse）

瞬变脉冲，又称尖峰或者电压闪变，是指在小于电网半个周期的时间内电网理想正弦波上叠加的窄脉冲。引起瞬变脉冲的原因很多，一般主要由以下几方面：

瞬变脉冲，又称尖峰或者电压闪变，是指在小于电网半个周期的时间内电网理想正弦波上叠加的窄脉冲。引起瞬变脉冲的原因很多，一般主要由以下几方面：

1.5.1 内部过电压（Internal overvolttage）

即在电力系统的内部，由于重负荷、感性负荷、补偿电容的投入和切除，开关和保险装置的操作以及短路故障的发生，都会使系统参数发生变化，引起电力系统的内部电磁能量的转化和传递，在系统中出现过电压。据统计，在整个瞬变脉冲事故中因内部过电压造成的占有80％。

1.5.2 雷电（Lightning）

在雷电中心1.5km～2km范围内都可能产生危险过电压，损坏电路上的设备。当雷击输电线或雷闪电发生在线路附近时，通过直接或间接耦合方式雷闪放电形成暂态过电压将以流动波形式沿线路传播，危及设备安全。据统计，在整个瞬变脉冲事故中因雷击产生过电压造成的约占18％左右。

计算机和精密仪器设备的信号电压很低，一般只有10V左右，所以对闪电脉冲过电压极为敏感，极易受闪电脉冲过电压的干扰和损坏。一般电气设备允许的闪电脉冲电压为6000V，而计算机和精密仪器设备估计在几十伏到几百伏就会受到损坏。

1.6 三相不平衡（Unbalance three phase circuit）

由于三相负荷分配不均等，使三相负荷电流不对称，由此产生三相负序分量。不平衡度是衡量三相负荷状态的指标，主要包括电压不平衡、电流不平衡、相角不平衡。三相不平衡窨到什么程度才会影响计算机的稳定、可靠运行，目前尚无完整资料。只有参考厂商关于三相不平衡具体要求，以保证计算机及其设备正常、稳定运行。一般计算机允许相电压不平衡≤120±3。

1.7 瞬间停电（Interrupt power－supply）

如果发生电网瞬间停电，将直接影响计算机的正常运行。当电源中断1.5ms以内是，可由计算机主机的大电容器放电来维持计算机的继续运行，对系统无影响。而当在电源中断1.5ms以上时，由于存储器一般采用MOS电路，一旦停电时间长，计算机就会失去记忆，使大量运算过程的数据丢失，致使计算机运算错误乃至停机。一般计算机要求电源中断在10ms之内。对于瞬间停电允许持续时间，《规范》中对供电质量规定分为A、B、C三级。

A级：Oms～4ms；B级：4ms～200ms；C级：200ms～1500ms。

1.8 电磁干扰（Electromagnetic Interference 简称EMI）

电磁干扰，有也称电磁污染，它是电子系统辐射的寄生电能。电磁干扰主要来自以下两方面：

①电缆、电线既是造成电磁干扰的主要发生器，也是主要的接收器。作为发生器，它向空间辐射电磁波，对计算机系统形成的干扰。作为接收器，它也能敏感地接收从其它相邻干扰源所发射电磁波的干扰。由于计算机系统中的逻辑脉冲前沿很陡峭（纳秒级），对30Hz-100Hz的电磁干扰十分敏感，会使计算机系统中的逻辑出现错误动作。

②核电脉冲（Nuclear Electromagnetic Pulse简称NEMP）核爆炸产生的电磁脉冲强度高、覆盖面大、持续时间短（1μs）、等值频率可高过100MHz.电磁脉冲将在电网络中耦合产生暂态过电压，危害极大。

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捷克首都布拉格的英文介绍

Danxia geography is a very important term. It refers to the red sandstone separated by the long-term weathering and water erosion, forming an isolated mountain peak and a steep rock is a thick red sandstone and conglomerate layer along the vertical joints of the various development Danxia Qifeng their customers. Developed mainly in the Jurassic to Tertiary level or Gentle red strata, in the northern part of Guangdong Province, China Danxiashan most typical found in. On the 1930's and 1940's. Zhongshan University geology at the original CHEN Guoda Professor "Danxia terrain" and to promote the concept of the South China Danxia terrain; 40-70 late 1960s, the former WU Shang-Zhongshan University, Department of Geography, Cengzhaoxuan Professor Hung-the landscape as an independent type of rock landscape of the system research, make "Danxia landform," the term widely disseminated to the 1980's, scientific workers of China has 21 provinces, nearly 400 Danxia landform of on-site inspection, Danxia landform and research into the country. 1991 in Guangdong Province Danxiashan convening of the first session of the National Tourism Development Danxia landform Colloquium and the establishment of a "national Danxia landform Tourism Development Studies." Danxia Mountain is Danxia Danxia landform and stratigraphic nomenclature, is now a National Nature Reserve geological features. Danxia landform development began in the late 3rd century Himalayan orogeny. The Movement of the Red strata have skewed and ease fold and make red basin uplift, forming the outflow area. Central Basin water to the low-lying central along the vertical joints rock erosion, the formation of defects vertical ditch, known as Roadway Valley. Cliff Valley Avenue to the foot of collapsing objects in the water is not entirely removed, the formation of a gentler slope of the plot cone collapse. With the trench wall collapses back, collapsing upward growth cone, the bedrock surface coverage area has also been expanding. Beng plot cone bottom and the bedrock to form a cone collapse plot tilt the same direction, the gentle slope. Cliff face after the failure to make refunds Peak surface gradually narrowing, Fort-residue forming peaks 532 or columns, and other features. Further erosion, residue peak, and 532 columns will disappear, and form gentle hills. Red Conglomerate There are plenty of calcium carbonate limestone gravel and cement. calcium carbonate dissolved in the water often forming some solution groove, rock and cave bud, or the formation of thin travertine deposition, even a stone cystolith development. Interchanges along the joints also funnel development. In sandstone, due to cross-stratification formed embroidered Kam-like terrain, known as Kam Shek. River deep rocks can be formed Top aligned, the walls of the steep mountain side, or cut into a variety of Qifeng, a tower of the fortress-like, such as pagoda-like. Strata dip in larger areas, such as the erosion of the dragon undulating form of monoclinic ridgelines; Many monoclinic adjacent ridge known as the monoclinic-group. Rock along the vertical joints major area collapsed, forming tall, a spectacular steep slopes. steep slope along a major group of the joint development to create the tall stone wall; 532 formation of corrosion wear stone window; Stone window to further expand into the stone bridge. Often block the formation of the steep narrow roadway Valley, and when a red rock known as "Cliff", a wall often along the level of the cavern. Guangdong, China Danxiashan, Jingjiling, Nanxiong the Wild Mountains, the far - and five fingers Nantaitou Shi Shi, Jiangxi Eagle River, Yiyang, Shangrao, Ruijin, Ningdu, Fujian Wuyishan, Citylink, Taining Bank, Zhejiang Yongkang, Xinchang, the BAI Guiping, Guangxi, the Doujiaoshan Rong, Sichuan at the same time, the sinus Hill, Guanxian the Qingcheng Mountain, Shaanxi Province, China's Red Hill, and Chengde, and so on, the typical Danxia landform. Danxia landform area is often Qifeng creates magnificent scenery, rich in tourism resources, such as Danxiashan, Jingjiling. Wuyishan have long been a well-known scenic spots, but along the vertical joints collapse of the cliff so thick red sand, Conglomerate exposed to research and restore the Red Basin palaeogeographic environment is of great significance. Danxia Mountain in Shaoguan City, 54 kilometers northeast, from 9 km Renhua county, Guangdong is one of the four famous mountains (the remaining three are famous Louvre Hill, four Popular Hill, Dinghushan) geological features for the state nature reserve. Danxiashan elevation 408 meters, is not high, but the cliff, far appears stains Xia, close attention is colorful, Many precipice, which was as sharp as the Hammer, points to the sky, the United States and countless rocks, holes, hidden in the mountains, and the scenery is Wonderful and Beautiful. Thus, it was once said of an overstatement : "Guilin enjoys landscapes, less than a Danxia in Guangdong." Danxiashan rock containing calcium, iron hydroxide and a small amount of gypsum, red, red sandstone terrain representatives, typical Danxia landform. Danxia Mountain can be divided into upper, middle or lower classes. The upper area of a Presbyterian peak, conch peak-Mount Everest. Presbyterian-built on a two-tier "Yufeng Pavilion", sunrise is a good place, can accommodate 200 people. In the booth can see around the mitral peak, and hopes to Lang, candles peak beauty backwater, the sea of clouds, and other scenic spots. Conch peak "Lo top and Buddha," there are many nearby acacia tree. Conch under rocks, Ming Yan, Xue Yan, late show rock, rock penetration, such as grass cliff caves. Bao Feng Yong Chui Hongqiao is, the rudder Stone Chaoxi, presses and three other spots. In the middle area of the Temple handful of major attractions, from here to deliver Gap, just clap your hands together like a rock on both sides of the general, visitors must be careful, walking FUNICULAR, They do up. "You Tong Airbus" vigorous four characters carved in stone walls, and add more of the risk of potential here, people Fireweed cold. But this steep staircase FUNICULAR Dan has built a solid bars and escorted loading very safe. Lower node Kam main attraction in the cavern days. In a natural cavern where Kwun Yam Temple, carved in the cave can see the Mawei vents, such as wind Liyudiaolongmen. Here is a very famous "dragon scales Stone", as the seasons change and transform color. Class scenic spots to drill tunnels through rock crevices, the more stimulation. Danxia Mountain is a clear Jinjiang, between around the mountain, visitors can roam interior, enjoy the scenery along the river and the two sides Cliff.。

淘宝中卖家的实名认证和支付宝认证都必须同一个人吗？

Prague is the capital of the Czech Republic and the largest city in the country, the state Bohemia, the Vltava River. The city is located in the center of Europe, has always been important in the transport position, the links with neighboring countries is also very close (especially in geographically between Berlin and Vienna, just the 2 middle of the German nation's capital.) March 2006, Prague area of 496 square kilometers, a population of 1,183,000. Located in the center of the Eurasian continent, across the Vltava River cloth sides. Area of 496 square kilometers. Population of about 121 million. Undulating terrain, the lowest point of elevation of 190 meters, 380 meters above sea level the highest point. Climate is typical mid-continent type. July average temperature is 19.5 ℃, 1 月 -0.5 ℃. About 500 mm of annual precipitation .。

布拉格是捷克共和国的首都和最大的城市，位于该国的中波希米亚州、伏尔塔瓦河流域。该市地处欧洲大陆的中心，在交通上一向拥有重要地位，与周边国家的联系也相当密切（特别是在地理上恰好介于柏林与维也纳这2个德语国家的首都中间）。2006年3月，布拉格的面积为496 平方千米，人口为118.3万。位于欧亚大陆中心，跨伏尔塔瓦河布两岸。面积496平方千米。人口约121万。地形波状起伏，最低点海拔190米，最高点海拔380米。气候为典型的中部大陆型。7月平均气温19.5℃， 1月－0.5℃。年降水量约500毫米。

英雄联盟常说的‘浪’用英文怎么说？

“淘宝实名认证”就是“支付宝实名认证”，两个账户是互相绑定，就是属于一个人的。

淘宝和支付宝认证不同人完全无意义！淘宝等于店面，支付宝等于钱柜。你管理商店，收到钱都算别人的你说行吗？这都不是必须的问题了。

买家确认收货后，钱会到支付宝，你在支付宝操作提现到银行卡就行。银行卡也要是你认证的信息同名的账户。转到其他名字的卡上也可以，要收手续费。

毕业寄语英文

Troll

我平常就在欧服玩的lol，在有人不好好玩或者说玩得很随便的时候别人就会说he is trolling, 也就是他在浪。

这只是指一个人能玩的好但故意没有的时候，并不是说一个人玩的很烂。

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