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1.
分析了智能小区的功能特点,根据智能小区网络的特殊性,对智能小区的网络系统进行了设计,并且重点介绍了智能小区局域网扩展方式的设计及实现。  相似文献   

2.
智能化住宅小区通信网络是小区内综合信息服务、小区与外界广域网连接、小区智能物业管理的物理平台。本文给出了基于以太网技术的智能化住宅小区通信网络平台的设计方法,提出了采用CEBUS技术设计家庭局部网络系统的方案。  相似文献   

3.
智能住宅区室外弱电线缆的布线设计是智能小区弱电专业工程设计中十分重要的组成部分,能否做好小区室外弱电布线设计既关系到当前小区智能系统功能的有效发挥,也影响小区今后在智能技术方面能否可持续发展,还决定了室外弱电线缆是否便于维护管理。此外,室外弱电线缆的敷设费用也会占智能系统总投资的很大一部分,因此,做好智能小区室外弱电工程的设计也将在节约总投资方面具有很大的意义。  相似文献   

4.
随着信息网络时代的迅速到来,智能化小区是这一时代的必然产物,它不仅是社会信息化的需要,同时也是经济国际化的需要。综合布线系统是智能化小区的神经系统,智能化小区必须借助于综合布线系统才能实现其智能化。如何在城市规划设计中做好智能化小区综合布线系统的规划设计,把智能化小区综合布线系统纳入城市规划设计中,使城市规划具有前瞻性,城市的发展具有可持续性是本文的基本思想。  相似文献   

5.
介绍了一种基于无线通信智能小区门禁系统,旨在通过计算机集中管理小区内的各个门禁控制器,监控小区内各个单元的门锁开关情况。定时汇总小区居民出入情况,及时处理各种门锁报警信息。设计采用专用的无线传输模块作为门禁控制器与计算机的通信工具。完成了读卡模块设计,阐述了系统通信协议。  相似文献   

6.
探讨基于ArcIMS的WebGIS技术在小区物业管理中的应用,以珠江某物业管理小区为例,建立了物业管理小区地理信息系统,并对系统的结构设计、数据库设计以及功能设计与实现作了较详细的分析。实践证明,将WebGIS应用于现代物业管理中是可行的,并且将成为小区信息化和智能化发展的新方向。  相似文献   

7.
以智能化供电小区建设为切入点,分析了EPON技术在智能化供电小区用电信息采集系统建设中所具有的优势,从系统设计的实用性和先进性出发,结合EPON技术设计了一套适合于智能化供电小区用电信息采集系统的EPON网络通信模型,并利用光纤通信、智能电表、面向用户和台区责任人的用电互动平台,实现小区用户用电情况的远程核查,以贵阳欣歆园小区用电信息采集为例验证了该系统的实用性。  相似文献   

8.
现代化智能小区的构建   总被引:1,自引:1,他引:0  
本文在分析智能小区系统结构的基础上,给出了智能小区系统设计框架和设计原则并提出了智能小区管理系统软件结构模型及其主要功能。  相似文献   

9.
小区重选能够保证为卫星终端提供不间断的服务。为了能更节能、更高效地完成小区重选,分别对卫星终端正常模式及低功耗模式下的小区重选进行了设计。小区重选过程中,为了使终端在切换频点后能够正常接收信道数据,分别提出了频率校正信道(Frequency Correction Channel,FCCH)同步和帧及时隙同步两种方法,并在低功耗场景中对这两种同步方法进行优化。经过实测功耗数据,优化后的方法实现过程功耗更低、效率更高;经过JY5000软件仿真后,设计的小区重选方案满足协议一致性。  相似文献   

10.
智能化小区集中监控管理系统设计研究   总被引:3,自引:0,他引:3  
本文首先分析了智能小区应具有的功能,然后讨论了智能小区的微机监控系统的几种设计方法,并进行了比较。最后,介绍了一个智能小区的供水监控系统。  相似文献   

11.
Spring-summer (November, December, January) ice sheet and sea ice regional surface albedo, surface temperature, sea ice concentration and sea ice extent averages and trends from 1981 to 2000 have been calculated for the Antarctic area. In this research the AVHRR Polar Pathfinder 5-km EASE-Grid Composites and the combined SMMR and SSMI data sets from the National Snow and Ice Data Center (NSIDC), Boulder, Colorado have been employed. A regional analysis has been made for five longitudinal sectors around Antarctica: the Weddell Sea (WS), the Indian Ocean (IO), the Pacific Ocean (PO), the Ross Sea (RS) and the Bellingshausen-Amundsen Sea (BS). The IO and PO sectors show ice sheet albedos of 0.85 and temperatures of − 25 °C. The corresponding values in the RS and BS sectors are 0.80 and − 16 °C respectively. The sea ice albedo is about 0.60 in the RS, BS and WS sectors and 0.55 in the IO and PO sectors. The average sea ice temperature varies around − 12 °C. All the sectors show slight increasing spring-summer albedo trends and decreasing spring-summer temperature trends and similar interannual variability in albedo and surface temperature. The steepest ice sheet albedo trend of 0.0019 ± 0.0009/yr is found in the RS sector. The steepest sea ice albedo trend of 0.0044 ± 0.0017 /yr occurs in the PO sector. The steepest temperature trends for both the ice sheet and sea ice occur in the BS sector, having values of − 0.075 ± 0.040 °C/yr and − 0.107 ± 0.027 °C/yr respectively. The sea ice concentration shows slight increasing trends, the highest being in the PO sector (0.3 ± 0.12%/yr), whereas the sea ice extent trends are near zero with the exception of the RS sector (14,700 ±8600 km2/yr) and the BS sector (− 13,000 ± 6400 km2/yr).  相似文献   

12.
This study examined the effect of hyperthermia on brain electrical activity measured with encephalography during prolonged exhaustive exercise in a group of sedentary women (VO2max = 35 ± 4 mL kg min−1). Two strenuous cycling exercises were performed either in neutral (N-Ex) or in heat (H-Ex) conditions. Tympanic temperature (Tty), heart rate (HR), body mass loss (BML), plasma volume decrease, and brain electrical activity [EEG: α (8–13 Hz) and β(13–30 Hz)-band and α/β index of fatigue: the ratio between EEG activity in the α band and β-band] were recorded throughout the cycling sessions. The Tty increase 1.0 °C in the N-Ex and 1.8 °C in H-Ex. HR increased in both sessions but with significantly higher values during the H-Ex session when compared with the N-Ex session (p < 0.001) (from 85 ± 4 beats min−1 to 164 ± 6 beats min−1 and from 83 ± 6 beats min−1 to 181 ± 8 beats min−1, respectively in N-Ex and in H-Ex). This was associated with a significantly higher BML (p < 0.05) and a higher plasma volume decrease in the H-Ex session (p < 0.01). The α/β index increased significantly during both trials particularly during the H-Ex session (p < 0.05). This was associated with a significant decrease of time to exhaustion (−34%). We suggest that exhausting work in the heat induced a change in gross brain activity (alpha/beta ratio) compared to a longer, less thermally demanding exposure. Fatigue in the heat could be attributed to central factors as well as thermal, cardiac and hydro-electrolytic impairment.  相似文献   

13.
D.H.  B.L.  E.A.  R.O.   《Sensors and actuators. A, Physical》2008,147(2):553-560
Surface properties can markedly affect the mechanical behavior of structural thin films used in microelectromechanical systems (MEMS) applications. This study highlights the striking difference in the sidewall surface morphology of n+-type polysilicon films from two popular MEMS processes and its effect on fracture and fatigue properties. The sidewall surface roughness was measured using atomic force microscopy, whereas silicon oxide thickness and grain size were measured using (energy-filtered) transmission electron microscopy. These measurements show that the oxide layers are not always thin native oxides, as often assumed; moreover, the roughness of the silicon/silicon oxide interface is significantly influenced by the oxidation mechanism. Thick silicon oxides (20 ± 5 nm) found in PolyMUMPs™ films are caused by galvanic corrosion from the presence of gold on the chip, whereas in SUMMiT V™ films a much thinner (3.5 ± 1.0 nm) native oxide was observed. The thicker oxide layers, in combination with differences in sidewall roughness (14 ± 5 nm for PolyMUMPs™ and 10 ± 2 nm for SUMMiT V™), can have a significant effect on the reliability of polysilicon structures subjecting to bending loads; this is shown by measurements of the fracture strength (3.8 ± 0.3 GPa for PolyMUMPs™ and 4.8 ± 0.2 GPa for SUMMiT V™) and differences in the stress-lifetime cyclic fatigue behavior.  相似文献   

14.
The present study developed a hybrid semi-automatic method to extract the liver from abdominal computerized tomography (CT) images. The proposed hybrid method consists of a customized fast-marching level-set method for detection of an optimal initial liver region from multiple seed points selected by the user and a threshold-based level-set method for extraction of the actual liver region based on the initial liver region. The performance of the hybrid method was compared with those of the 2D region growing method implemented in OsiriX using abdominal CT datasets of 15 patients. The hybrid method showed a significantly higher accuracy in liver extraction (similarity index, SI = 97.6 ± 0.5%; false positive error, FPE = 2.2 ± 0.7%; false negative error, FNE = 2.5 ± 0.8%; average symmetric surface distance, ASD = 1.4 ± 0.5 mm) than the 2D (SI = 94.0 ± 1.9%; FPE = 5.3 ± 1.1%; FNE = 6.5 ± 3.7%; ASD = 6.7 ± 3.8 mm) region growing method. The total liver extraction time per CT dataset of the hybrid method (77 ± 10 s) is significantly less than the 2D region growing method (575 ± 136 s). The interaction time per CT dataset between the user and a computer of the hybrid method (28 ± 4 s) is significantly shorter than the 2D region growing method (484 ± 126 s). The proposed hybrid method was found preferred for liver segmentation in preoperative virtual liver surgery planning.  相似文献   

15.
Landsat-based inventory of glaciers in western Canada, 1985-2005   总被引:10,自引:0,他引:10  
We report on a glacier inventory for the Canadian Cordillera south of 60°N, across the two western provinces of British Columbia and Alberta, containing ~ 30,000 km2 of glacierized terrain. Our semi-automated method extracted glacier extents from Landsat Thematic Mapper (TM) scenes for 2005 and 2000 using a band ratio (TM3/TM5). We compared these extents with glacier cover for the mid-1980s from high-altitude, aerial photography for British Columbia and from Landsat TM imagery for Alberta. A 25 m digital elevation model (DEM) helped to identify debris-covered ice and to split the glaciers into their respective drainage basins. The estimated mapping errors are 3-4% and arise primarily from seasonal snow cover. Glaciers in British Columbia and Alberta respectively lost − 10.8 ± 3.8% and − 25.4% ± 4.1% of their area over the period 1985-2005. The region-wide annual shrinkage rate of − 0.55% a− 1 is comparable to rates reported for other mountain ranges in the late twentieth century. Least glacierized mountain ranges with smaller glaciers lost the largest fraction of ice cover: the highest relative ice loss in British Columbia (− 24.0 ± 4.6%) occurred in the northern Interior Ranges, while glaciers in the northern Coast Mountains declined least (− 7.7 ± 3.4%).  相似文献   

16.
In this paper, we give characterizations of ordered semigroups in terms of (∈, ∈ ∨q)-fuzzy interior ideals. We characterize different classes regular (resp. intra-regular, simple and semisimple) ordered semigroups in terms of (∈, ∈ ∨q)-fuzzy interior ideals (resp. (∈, ∈ ∨q)-fuzzy ideals). In this regard, we prove that in regular (resp. intra-regular and semisimple) ordered semigroups the concept of (∈, ∈ ∨q)-fuzzy ideals and (∈, ∈ ∨q)-fuzzy interior ideals coincide. We prove that an ordered semigroup S is simple if and only if it is (∈, ∈ ∨q)-fuzzy simple. We characterize intra-regular (resp. semisimple) ordered semigroups in terms of (∈, ∈ ∨q)-fuzzy ideals (resp. (∈, ∈ ∨q)-fuzzy interior ideals). Finally, we consider the concept of implication-based fuzzy interior ideals in an ordered semigroup, in particular, the implication operators in Lukasiewicz system of continuous-valued logic are discussed.  相似文献   

17.
The pack hike test (PHT, 4.83 km hike wearing a 20.4-kg load) was devised to determine the job readiness of USA wildland firefighters. This study measured PHT performance in a sample of Australian firefighters who currently perform the PHT (career land management firefighters, LMFF) and those who do not (suburban/regional volunteer firefighters, VFF). The study also investigated the relationships between firefighters' PHT performance and their performance across a range of fitness tests for both groups. Twenty LMFF and eighteen age-, body mass-, and height-matched VFF attempted the PHT, and a series of muscular endurance, power, strength and cardiorespiratory fitness tests. Bivariate correlations between the participants’ PHT finishing time and their performance in a suite of different fitness tests were determined using Pearson’s product moment correlation coefficient. The mean PHT finishing time for LMFF (42.2 ± 2.8 min) was 9 ± 14% faster (p = 0.001) than for VFF (46.1 ± 3.6 min). The pass rate (the percentage of participants who completed the PHT in under 45 min) for LMFF (90%) was greater than that of VFF (39%, p = 0.001). For LMFF, VO2peak in L min−1(r = −0.66, p = 0.001) and the duration they could sustain a grip ‘force’ of 25 kg (r = −0.69, p = 0.001) were strongly correlated with PHT finishing time. For VFF, VO2peak in mL kg−1 min−1(r = −0.75, p = 0.002) and the duration they could hold a 1.2-m bar attached to 45.5 kg in a ‘hose spray position’ (r = −0.69, p = 0.004) were strongly correlated with PHT finishing time. This study shows that PHT fitness-screening could severely limit the number of VFF eligible for duty, compromising workforce numbers and highlights the need for specific and valid firefighter fitness standards. The results also demonstrate the strong relationships between PHT performance and firefighters’ cardiorespiratory fitness and local muscular endurance. Those preparing for the PHT should focus their training on these fitness components in the weeks and months prior to undertaking the PHT.  相似文献   

18.
Phase equilibria of the TiAl-rich part of the Ti–Al–Ni ternary system have been studied experimentally by scanning electron microscopy and electron probe micro-analysis of heat-treated alloys. Partial isothermal sections involving the liquid, β-Ti, α-Ti, α2-Ti3Al, γ-TiAl and τ3-Al3NiTi2 phases were constructed between 1623 and 1273 K. Eight three-phase regions of the L + β + α, L + α + γ, L + β + γ, β + α + γ, L + β + τ3, β + γ + τ3, β + α2 + τ3 and α2 + γ + τ3 were derived. Extrapolations of these tie-triangles indicate the occurrence of three transition-type reactions; L + α = β + γ at around 1593 K, L + γ = β + τ3 at around 1553 K, and β + γ = α + τ3 at around 1393 K. The Ni solid solubility in the α and α2 phase is extremely low, less than 1 at.% in all studied temperature ranges.  相似文献   

19.
High-order resonant modes of piezoelectric-excited cantilever (PEMC) sensors were previously shown to be very highly sensitive at 0.3-2 fg/Hz for in-liquid applications. The purpose of this work is to show experimentally and with finite element model (FEM) simulations that such sensitive modes are strongly influenced by the sensor width, suggesting that the sensitive modes are torsional or buckling modes. From experimental observations the resonant frequency of high-order modes had a strong dependence on width, where a sensor with a smaller width had resonant modes at a higher frequency. Also the FEM simulations indicate that in this frequency range there are resonant modes with a buckling nature that change for a decrease in width, consistent with experimental observations. In order to establish that the width-dependent modes are mass-sensitive in liquids, resonant frequency change to density changes in flow experiments under fully liquid-immersed conditions were determined. Average frequency shifts of 475 ± 49 Hz (n = 5), 533 ± 31 Hz (n = 5), 715 ± 103 Hz (n = 5) and 725 ± 37 Hz (n = 5) were obtained for the four designs investigated in response to a density change of 0.0118 g/cm3. The results show that the resonant frequency response to variations in the geometry provides insightful data on the role of width in PEMC sensor design.  相似文献   

20.
Accurate estimation of phytoplankton chlorophyll a (Chla) concentration from remotely sensed data is particularly challenging in turbid, productive waters. The objectives of this study are to validate the applicability of a semi-analytical three-band algorithm in estimating Chla concentration in the highly turbid, widely variable waters of Taihu Lake, China, and to improve the algorithm using a proposed four-band algorithm. The improved algorithm is expressed as [Rrs(λ1)− 1 − Rrs(λ2)− 1][Rrs(λ4)− 1 − Rrs(λ3)− 1]− 1. The two semi-analytical algorithms are calibrated and evaluated against two independent datasets collected from 2007 and 2005 in Taihu Lake. Strong linear relationships were established between measured Chla concentration and that derived from the three-band algorithm of [Rrs− 1(660) − Rrs− 1(692)]Rrs(740) and the four-band algorithm of [Rrs− 1(662) − Rrs− 1(693)][Rrs− 1(740) − Rrs− 1(705)]− 1. The first algorithm accounts for 87% and 80% variation in Chla concentration in the 2007 and 2005 datasets, respectively. The second algorithm accounts for 97% of variability in Chla concentration for the 2007 dataset and 87% of variation in the 2005 dataset. The three-band algorithm has a mean relative error (MRE) of 43.9% and 34.7% for the 2007 and 2005 datasets. The corresponding figures for the four-band algorithm are 26.7% and 28.4%. This study demonstrates the potential of the four-band model in estimating Chla even in highly turbid case 2 waters.  相似文献   

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