“蓝牙”(Bluetooth)本是10世纪统一了丹麦的国王的名字，现取其“统一”的含义、用来命名意在统一无线局域网通信标准的蓝牙技术。
1998年5月，爱立信、诺基亚、东芝、IBM和英特尔五家著名厂商在联合开展短程无线通信技术的标准化活动时提出了“蓝牙技术”这一概念。蓝牙技术是一种提供短距离无线传输的应用技术。这五家厂商力图使蓝牙技术能够成为未来的无线通信标准。这种全球统一的标准带来了无穷无尽的创造力。
蓝牙技术在现代通信网络的最后10米，将像一种无处不在的数字化神经末梢一样，把各种网络终端设备、各种信息化设备，都“无线”地连接起来。利用蓝牙技术，能够有效地将移动电话与笔记本电脑、掌上电脑以及各种数字化的信息设备连接起来，从而甩掉常用的有线通信电缆；同时形成一种个人身边的网络，使得身边的各种信息化的移动便携设备都能无缝地实现资源共享。
因为其开放性，蓝牙技术目前只是一个规范，还没有成为行业标准。不同品牌、型号的设备之间互通还存在一些问题。但蓝牙技术本身具有很多优势：蓝牙一般工作在不需缴纳费用的全球通用的工业、科学和医疗频段，即2.4GHz的1SM频段上；可实时进行数据和语音传输；由于采用了先进的调频和纠错编码技术，蓝牙具有很好的抗干扰能力，在配备了蓝牙的设备之间可以进行更加可靠的通信。另外，蓝牙具有很强的移植性，可应用于多种通信场合，如WAP、GSM等，引入身份识别后可以灵活实现漫游。而且蓝牙设备功耗低，容易实现，便于推广，对人体危害也小。
就目前的发展情况来看，蓝牙技术在手机、耳机、PAD、数码相机和数码摄影机等设备上都有应用，也正应用于无线设备、图像处理设备、安全产品、消费娱乐、汽车产品、家用电器等诸多领域。就蓝牙手机而言，它可以很方便地和电脑连接，实现文件互传，除了图片、铃声、和Java小游戏外，一般的文档也能传到蓝牙手机中，这样就可以把蓝牙手机当成U盘使用了。蓝牙手机能够在一定范围内与笔记本电脑无线连接，让笔记本电脑无线上网成为现实。两个同样持有蓝牙手机的用户还可以通过手机交换名片、电话和手机铃声，或者无线联机游戏。再加上相匹配的蓝牙头盔、蓝牙眼镜、蓝牙外套等一系列产品，蓝牙的无线优点可以
A. 蓝牙技术是用丹麦国王名字命名，意在统一无线局域网通信标准的无线传输应用技术
B. 蓝牙技术是由爱立信、诺基亚、东芝、IBM和英特尔联合提出的未来的无线通信标准
C. 蓝牙技术是信息设备间及信息设备与网络间的一种短距离无线化通信传输应用技术
D. 蓝牙技术是一种能把各种网络终端设备、各种信息化设备连接起来的无线通信标准
| {{B}}New Foods and
the New World{{/B}} In the last 500 years, nothing about people—not their clothes, ideas, or languages—has changed as much as what they eat. The original chocolate drink was made from the seeds of the cocoa tree (可可树) by South American Indians. The Spanish introduced it to the rest of the world during the 1500’s. And although it was very expensive, it quickly became fashionable. In London, shops where chocolate drinks were served became important meeting places. Some still exist today. The potato is also from the New World. Around 1600, the Spanish brought it from Peru to Europe, where it soon was widely grown. Ireland became so dependent on it that thousands of Irish people starved when the crop failed during the "Potato Famine (饥荒)" of 1845—1846, and thousands more were forced to leave their home A. One third of the world’s population drinks coffee. B. Coffee is native to Colombia. C. Coffee can keep one awake. D. Coffee drinks were first made by Arabs. [单选题]驾驶人在下列哪种情况下不能驾驶机动车？
A.A.饮酒后 B.B.喝茶后 C.C.喝咖啡后 D.D.喝牛奶后 E.略 F.略 G.略 [单项选择]批准逮捕，由( )负责。
A. 公安机关 B. 人民法院 C. 人民检察院 D. 安全机关 [多项选择]备查账簿与总分类账簿相比，存在以下不同之处( )。
A. 账簿的格式不同 B. 登记依据不同 C. 登记时间不同 D. 账簿的登记方法不同 [多选题]着火后,燃烧面积按防护堤内的面积计算的容器是( )( 中 )
A.半地上卧式罐 B.油池 C.浮顶油罐 D.上卧式罐 [单项选择]指出下列哪一种税是以企业和个人从事工业制造、商品经营或提供劳务等生产劳动的增值额为征税对象的( )
A. 消费税，是由海关对进口货物代征收的一种附加税 B. 产品税，由海关在进口环节代征 C. 增值税，进口货物的增值税在货物进口时由海关代征 D. 进出口关税，货物进出口时由海关征收 [单项选择]在注射模斜导柱侧向分型抽芯机构中，斜导柱与开模方向的夹角一般不超过（）。
A. 10° B. 15° C. 25° D. 30 [判断题]在爆破施工中,杂散电流、静电感度、射频感应电等均可引起电爆网路中电雷管早爆。( )
A.正确 B.错误 [简答题]
In the span of 18 months, Isaac Newton invented calculus, constructed a theory of optics, explained how gravity works and discovered his laws of motion. As a result, 1665 and the early months of 1666 are termed his annus mirabilis. (46)It was a sustained sprint of intellectual achievement that no one thought could ever be equaled. But in a span of a few years just before 1900, it all began to unravel. One phenomenon after another was discovered which could not be explained by the laws of classical physics. (47) The theories of Newton, and of James Clerk Maxwell who followed him in the mid-19th century by crafting a more comprehensive account of electromagnetism, were in trouble.
Then, in 1905, a young patent clerk named Albert Einstein found the way forward. In five remarkable papers, he showed that atoms are real (it was still controversial at the time), presented his special theory of relativity, and put quantum theory on its feet. It was a different ac [判断题]倒闸操作中不准擅自更改操作票，不准随意解除闭锁装置。
A.正确 B.错误 [判断题]膝反射异常与腰5骶1椎间盘后突无关。
[多选题]高层建筑火灾的特点是( )。
A.烟、火蔓延途径多，容量形成立体火灾 B.人员疏散困难 C.灭火救援难度大 D.易造成玻璃幕墙破碎 [单项选择]启动Word后可以新建文档的个数是( )。
A. 1个 B. 4个 C. 6个 D. 受内存空间的限制 [判断题]当电气火灾发生时,如果无法切断电源,就只能带电灭火,并选择干粉或者二氧化碳灭火器,尽量少用水基
式灭火器。
A.正确 B.错误 我来回答: 提交
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