可结合的

This property of composition is called associativity.

复合的这个性质叫做可结合性。

If we consider the integers with ordinary multiplication we have closure , associativity, and identity element.

如果我们考虑整数集且用通常的乘法，我们有封闭性，可结合性，和一个单位元。

Linking to the request of the research subject, it designs and tests the cassegrain optical antennas.

结合安装工艺等因素，提出了系统相应可采用的抑制或缓解措施。

In particular,it can be used by certified mail protocol,and based on the scheme a multi-party certified mail protocol is proposed,its fairness and non-repudiation are proved.

本文在已有的两方签密方案的基础上结合组可验证的签密方案，提出了一种新的、可用于多方认证邮件协议的签密方案，进而设计出了异步的一对多的认证邮件协议，并证明了该协议的公平性与非否认性。

Especially, the technology of Automatic Gain Control and signal processing are studied which are key factors working on the performance of the receiver. Based on analyzing the theory of automatic Gain Control, operational amplifiers 0P37 and logarithmic D/Aconverter AD7111A are used to design variable gain amplifiers which can be controlled numerally, A/D convector LTC1405 is Used to test the echo, Complex Programmable Logic device is used for controller, and an arithmetic is designed for automatic Gain Control which is simulated and analyzed in order to test its feasibility.

本文在分析自动增益控制AGC原理的基础上，采用集成运放OP37和数控增益衰减器AD7111A设计可数字控制的可变增益运放模块；采用高速A／D转换器LTC1405作为回波信号检测模块；采用复杂可编程逻辑器件CPLD作为核心控制模块，构成数字自动增益控制电路，并设计粗调和细调步进控制相结合的算法，对回波信号的增益进行精确而快速的调节控制，使回波信号振幅快速稳定在设计指标范围内，利于接收机后续信号处理电路对回波信号作进一步的处理。

Ft Interior Volume Rear: 38.0 cu. ft Luggage capacity: 13.7 cu. ft Performance 0-50 mph (0-80 kmh): n/a 0-60 mph (Manual / Auto): 7.8 / 9.0 sec (7.8 sec / 9.6 sec. quattro) 1/4 Mile: n/a Top estimated speed: 130 mph (203 kmh)- Electronically limited for North America Fuel Economy City (Manual/Auto): 19 / 18 mpg (19 / 18 mpg quattro) Highway (Manual/Auto): 27 / 28 mpg (26 / 27 mpg quattro) Combined (Manual/Auto): 23 / 23 mpg (22 / 21 mpg quattro) Standard Features Comfort/Convenience:· Electronic automatic climate control system, including air conditioning · Power steel sunroof · Power windows with one-touch down, lock-out for rear windows, pinch protection and one-touch up for front windows · Retained accessory power for windows and sunroof · Tinted glass, banded windshield · Power rack and pinion steering · Convenience close feature for windows and optional sunroof · Electronic cruise control with resume and speed up features · Dual power mirrors with defog feature · Electric rear window defogger · Power central locking system including trunk and fuel door; selective unlocking · Heat ducts to rear seat area · Illuminated glove box, trunk, lighter/ashtrays, engine compartment · Ignition key with integral light · Dual illuminated vanity mirrors · 4-passenger assist handles · Time delay interior light · Anti-theft vehicle alarm system · Cupholders · Fuel cap hanger feature Interior/Seating and trim:· 8-way power front seats with manual lumbar adjustment · Front seat map pockets · Facette weave cloth · Leather-wrapped steering wheel · Fold down rear-center armrest with storage container · Rear center armrest · Full length center console with forward storage bin, including cupholders · 60/40 split/fold rear seat with locking seat back · Genuine burled walnut wood trim for dash, door panels and console · Front and rear carpet floor mats Instrumentation:· Backlit instrument cluster, red illumination · Tachometer and electric speedometer · Analog clock · Outside temperature gauge · Trip odometer · Coolant temperature gauge · Oil temperature gauge · Voltmeter · Intermittent wiper mode Audio Systems:· AM/FM stereo cassette radio with anti-theft · 6-speaker sound package · Rear window antenna · Preparation wiring for CD changer · Preparation for cellular phone Exterior:· Aerodynamic 3-way halogen headlights · 5 mph bumpers, painted in body color · Body color, protective side moldings · Retractable headlight washer system · Body color, flush door handles · Body color, outside mirror: right convex, left side flat · Front fog lights · Rear fog light (integrated with left light cluster) Safety:· Anti-lock brake system · Driver and front passenger air bag supplemental restraints · Automatic self-tensioning front seat belt system · Rear outboard 3-point seat belts with comfort adjustment · Rear center lap safety belt with retractor · Child-safety rear door locks

1 / 4 mile ：无/ 1 顶端估计速度：一百三十零英里每小时-电子有限公司，为北美洲燃油经济性市： 19 / 18哩（ 19 / 18哩quattro的）公路： 27 / 28哩（ 26 / 27哩quattro的）结合： 23 / 23哩（ 22 / 21哩quattro的）标准功能舒适/方便：·电子自动气候控制系统，包括空调·电源钢天窗·电源的Windows与一触式下降，锁定为后方的Windows ，夹保护和一触式，为前线的Windows ·保留配件权力for Windows和天窗·有色玻璃，带状挡风玻璃·电源机架和齿轮督导·方便接近的特点，用于Windows和可选的天窗·电子巡航控制与恢复，并加快特色·双电源镜与defog功能·电动后窗defogger ·电源中央门锁系统，包括主干和燃料的大门；选择性解锁·热导管后座区·照明手套箱，躯干，打火机/烟灰缸，引擎·点火的关键与积分光·双发亮的虚荣心镜· 4名乘客协助处理·时间延迟内部轻·反盗窃车辆报警系统· cupholders ·燃油上限吊架功能内部/座位和修剪：· 8路的权力前排座椅手动腰调整·前座地图的口袋· facette编织布·皮革包裹方向盘·折叠后方中心扶手与储藏容器·后方中心扶手·充分的长度中心控制台与储存着斌，包括cupholders · 60/40分裂/倍后座锁定椅背·真正的burled核桃木材装饰为短跑，车门面板和控制台·前方和后方，地毯，地板垫仪器仪表：·背光文书集群，红色照明·转速表和电动里程表·模拟时钟·室外温度衡量·行程里程表·冷却液温度衡量·油温计·伏特·间歇雨刮模式音频系统：·调幅/调频立体声收音机，镭射与反盗窃· 6喇叭声包·后窗天线·准备布线的CD换·准备蜂窝电话外墙：·气动3路卤素头灯·五英里每小时保险杠，描绘了在体色·车身颜色，保护方成型·可伸缩的头灯清洗系统·车身颜色，冲水门把手·车身颜色，外镜：右凸，左侧单位·前雾灯·后方雾轻安全：·汽车防抱死制动系统·司机及前座乘客安全气囊的补充约束·自动自我拉紧前座安全带系统·后方的舷外3点安全带与舒适性调整·后方中心濸安全带与retractor ·儿童安全后门的锁

The others are Mucuna sempervirens,Parthenocissus trcuspidata,Wistaria sinensis Sweet in turn.According to the distinction of ecological functional of these four plants,the kind of plants which should be chosen under various ecological environment conditions or for different demands of ecological function of the plants were given.1. The most suitable plants for the area which get serious pollution such as factory,roadway and so on is Mucuna sempervirens.the other plant which more suitable is Rosa banksiae Ait.2. The most suitable plants for the hospital and the area for the children and the old is Mucuna sempervirens. And we can also select Parthenocissus trcuspidata.3. In the green area of modern enterprise that produce precision instrument,Rosa banksiae Ait is the best selection.4. Rosa banksiae Ait is the most suitable plants in resident green area. Planting Mixed with Mucuna sempervirens has better effectiveness.

以四种植物的生态功能性差异评价为依据，提出不同生态环境条件下和对植物不同的生态功能性要求的垂直绿化应选择的植物： 1 在道路、工厂等污染较严重的地区搞垂直绿化，最合适的植物是油麻藤，其次可选择木香； 2 医院及儿童、老人活动区的垂直绿化首选是油麻藤，其次是爬山虎； 3 生产精密仪器的现代企业绿地，垂直绿化植物选择以木香为首选，可结合大面积的爬山虎墙面绿化； 4 居住区绿地的垂直绿化植物选择以木香最符合要求，再以油麻藤进行混植，效果较好。

Their correlation and influence were described,and it was proposed that in development of each procedure of green buildings and intelligent buildings,only the combinations of the two kinds of buildings can better realize the harmony and unity of "human-building-nature" and realize a circulable,harmonious and sustainable devel.

对国内外绿色建筑和智能建筑的概念、特点、评估体系和发展概况等方面进行了详细深入的相互比较研究，阐明了它们之间的相互关系和影响，并提出了我国在发展绿色智能建筑的各个程序上，应把二者相互结合才会更好地实现&人-建筑-自然&三者的和谐统一，并实现节约能源、资源、无害化、无污染、可循环的、和谐的、可持续发展社会。

In this study, nonionic surfactant sorbitan trioleate (Span 85) was modified with Cibacron Blue F-3GA to become an affinity surfactant (CB-Span 85) and to form affinity-based reversed micelles while dissolved in hexane. Since the CB molecule possesses a specific conformation that mimics nicotinamide adenine dinucleotide, it can bind strongly and specifically to a wide range of nucleotide-dependent enzymes such as dehydrogenases and kinases. Moreover, high protein transfer efficiency in the reverse micelles can be easily achieved by controlling the ionic strength of the aqueous phase.

本实验使用非离子型界面活性剂Span 85与蓝色染料分子Cibacron Blue F-3GA结合，形成具有亲和性的界面活性剂 CB-Span 85，由於CB染料分子具有与NAD+相似的结构，可与含核苷酸部位的蛋白质具有亲和力，将CB-Span 85溶於有机溶剂形成反微胞相，可有效的提高反微胞的选择率，可以只控制离子强度来调节蛋白质进出反微胞的效率。

Even more gratifying is that we have applied a combination of digital and analog technology, successfully developed an international leading level, the frequency can reach near 2MHZ, good repeatability, temperature coefficient of only 5 millionths per unit and can be long-term stability of the voltage frequency converter, which will enable new power meter can be achieved without long-term adjustment.

更可喜的是，我们已应用数字和模拟相结合的技术，成功研制出具有国际领先水平、频率可达近2MHZ，重复性好，温度系数仅每度百万分之五和能长期稳定的电压频率变换器，这将使新的电能表可做到长期不需调整。

John Robbins lives with his family in Santa Cruz, California.

约翰罗宾和家人居住在加利福尼亚州的圣克鲁斯县。

The international background is mainly the economic ties among different nations tented to be widen and deepen at the peace and development times.

国际背景主要是和平与发展时代条件下的世界各国经济贸易联系的日益加深。