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The miniaturization of microelectromechanical systems (MEMS) physical sensors is driven by global connectivity needs and is closely linked to emerging digital technologies and the Internet of Things. Strong technical advantages of miniaturization such as improved sensitivity, functionality, and power consumption are accompanied by significant economic benefits due to semiconductor manufacturing. Hence, the trend to produce smaller sensors and their driving force resemble very much those of the miniaturization of integrated circuits (ICs) as described by Moore's law. In this respect, with its IC-, and MEMS-compatibility, and scalability, the silicon nanowire is frequently employed in frontier research as the sensor building block replacing conventional sensors. The integration of the silicon nanowire with MEMS has thus generated a multiscale hybrid architecture, where the silicon nanowire serves as the piezoresistive transducer and MEMS provide an interface with external forces, such as inertial or magnetic. This approach has been reported for almost all physical sensor types over the last decade. These sensors are reviewed here with detailed classification. In each case, associated technological challenges and comparisons with conventional counterparts are provided. Future directions and opportunities are highlighted.  相似文献   
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Water Resources Management - Groundwater is an important source to supply drinking water demands in both arid and semi-arid regions. Nevertheless, locating high quality drinking water is a major...  相似文献   
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ABSTRACT

Initiatives to operationalize the concept of resilience in the building industry are rapidly emerging. The concept of resilience has introduced a way to explore solutions to some important problems in the building industry. However, much of the work that has taken place to date represents activities generally assigned to risk management, which is discussed as being inherently insufficient for sustaining the functions of the built environment under stresses. This commentary considers the opportunities and limitations for mainstreaming resilience into building industry processes and actors. Barriers include indeterminate analytical meaning, event and performance uncertainty, immature regulatory standards setting, and untested enterprise economics. Further, the multiple outcomes of recovery and the relationship between building recovery and adaptation are discussed and, along with economics of resilience investments, a research need highlighted. A simple heuristic is presented to illustrate the complement of resilience to risk management and advance the integration of resilience into existing industry workflows.  相似文献   
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In the present study, green tea extract was encapsulated in liposomes based on the Mozafari method (with no organic solvents) and characterized for its physicochemical properties (encapsulation efficiency, particle size, and Z-potential). Encapsulation efficiency, particles size, and Z-potential were determined to be 51.34, 419 nm, and -57 mV, respectively. Total polyphenol content of the green tea by Folin-Ciocalteu's phenol reagent was measured as 164.2 mg gallic acid/g extract. Free radical scavenging activities of free and liposomal extracts were 90.6 and 93.4%, respectively, using the DPPH method. Antioxidant activity of the ethanolic extract of green tea in free and liposomal forms with concentrations of 200, 600, and 1000 mg L−1 were assessed on oxidative stability of the canola oil at 60 °C for 0, 4, 8, 12, 16, 20, 24, 28, and 32 days. Results were compared to results of synthetic antioxidant butylated hydroxytoluene at 200 mg L−1. To assess antioxidant activity on canola oil stability, peroxide, thiobarbitoric acid, and anisidine values were assessed as well as the total oxidation value and rancimat test. Results showed that the liposomal green tea extract was more effective than the free extract. Furthermore, a 600 mg L−1 concentration of the green tea extract showed a significant antioxidant activity, compared to other extract concentrations. Increasing storage time and various concentrations of the ethanolic green tea extracts included significant effects on canola oil stability (P ≤ 0.05). Results demonstrated that the green tea extract could be used as an effective antioxidant. Free and liposomal extract (at 600 mg L−1) resulted in stronger functionality than the synthetic antioxidant butylated hydroxytoluene.  相似文献   
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An optimized Ternary CAM concept is introduced for the hardware search engines in high-speed Internet routers. Our design employs w + 1 RAM bits to store a word of size w, whereas a conventional TCAM needs 2w RAM bits for the same word size. Based on this concept an 8-bit cluster is designed out of 9 SRAM bits, used as the basic building block of our Prefix-CAM (PCAM) structure. Four such clusters merge to store a 32-bit IPv4 prefix, thus, configuring a PCAM suitable for Internet packet forwarding. This PCAM module employs 48% less SRAM cells and a total of 22% less transistors plus 50% less address decode interconnects compared to a conventional TCAM, for equal storage size and equal functionality. We show that PCAM can be employed for multifield packet classification. Other factors, such as lookup speed and power dissipation, are not adversely affected.  相似文献   
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Iran produces about 7000 metric tons of cumin seed meal (CSM) as a by‐product of cumin oil extraction factories, annually. To evaluate the nutritional significance of cumin seed meal as a broiler feedstuff, an experiment was conducted using 288 male broiler chicks (14 days old) receiving diets containing 0, 25 and 50 g kg−1 of CSM with and without polyethylene glycol (PEG) and enzyme (Grindazyme GP 15000) for 28 days. Total body weight (BW), body weight gain (WG), feed intake (FI), feed conversion ratio (FCR), weight of carcass and percentage of legs, breast and edible parts of carcass were measured. The results showed that, inclusion of CSM in broiler diets had no negative influence on parameters evaluated compared to the control diet containing wheat bran (P > 0.05). PEG and enzyme had no influence on the bird performance (P > 0.05). There was an increase in relative weight of gizzard when the amount of CSM in the diet was increased (P < 0.01). An increase in relative weight of gizzard in birds that received the CSM diet was likely to be due to the increase in fibre content of CSM diets. In respect of the low price of CSM, it could be concluded that inclusion of CSM at levels used in this experiment has no negative effect on broiler performance and reduces the overall cost of broiler production. Copyright © 2006 Society of Chemical Industry  相似文献   
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