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1.
This study gives fundamental knowledge on the particle classification performance by centrifugal separator.It is found that the cut size of a centrifugal separator decreases as the rotational speed increases and the liquid flow rate decreases. Fitting our experimental results with the theory, they agree with each other at high flow rate. However, the difference between them generates at low flow rate. This is because dead spaces are generated in the centrifugal separator at the low flow rate. Also, the computer simulation of the fluid behavior in the centrifugal separator can find the decrease of the velocity near the wall under the low flow rate, which suggests the possibility of the formation of dead spaces in the separator.  相似文献   
2.
In this paper, we propose a new energy efficient clustering scheme with transmission power control named “EACLE” (Energy-Aware CLustering scheme with transmission power control for sEnsor networks) for wireless sensor networks, which are composed of the following three components; “EACLE clustering” is a distributed clustering method by means of transmission power control, “EACLE routing” builds a tree rooted at a sink node and sets the paths from sensor nodes taking energy saving into consideration, and “EACLE transmission timing control” changes the transmission timing with different levels of transmission power to avoid packet collisions and facilitates packet binding. With an indoor wireless channel model which we obtained from channel measurement campaigns in rooms and corridors and an energy consumption model which we obtained from a measurement of a chipset, we performed computer simulations to investigate the performance of EACLE in a realistic environment. Our simulation results indicate that EACLE outperforms a conventional scheme such as EAD (Energy-Aware Data-centric routing) in terms of communication success rate and energy consumption. Furthermore, we fully discuss the impact of transmission power and timing control on the performance of EACLE.  相似文献   
3.
This paper presents a three-dimensional (3-D)-model-based navigation system for endoscopic sinus surgery treating paranasal sinusitis. Endoscopic surgery is becoming more common because of its low invasiveness. Its problem with disorientation, however, is one of the toughest barriers for the novice and may lead even an expert to commit serious surgical errors, e.g., causing cerebrospinal fluid (CSF) leakage or blinding the patient. To prevent such complications and optimize training, the authors' system aids in navigation by showing a single perspective view of the patient and the endoscope models. This virtual endoscope has a viewing cone with a simulated light to indicate the viewing direction and visual field in real-time. The system's three clipping planes automatically follow the endoscope and help keep the surgeon aware of the endoscope's actual position. An experiment comparing the system to conventional navigation using a triplanar display showed that the perspective view was referenced very frequently, giving a positive impressions, while the triplanar display was almost completely ignored, apparently because it was too difficult to interpret immediately  相似文献   
4.
This paper proposes novel grounded and floating high order series and parallel immittance simulators using operational transconductance amplifiers (OTAs) and operational amplifiers (OAs) with a finite gain–bandwidth (GB) product. They are composed of active devices (OTAs and OAs) and resistances, and are suitable for monolithic implementation in either CMOS or bipolar technologies. They also realize both positive and negative high order immittances. The circuit characteristics can be electronically tuned by adjusting the transconductances of OTAs and the GB products of OAs. Any transfer functions are realizable using the proposed simulators. Two examples are shown, together with simulation results.  相似文献   
5.
A simple high-performance liquid chromatographic (h.p.l.c.) method has been developed for determining total malondialdehyde (MDA), including free MDA and MDA released from its precursor in vegetable oils. Free MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1-dansyl-pyrazole(DP), was determined by h.p.l.c. The reaction releasing MDA from its precursor requires Fe3+ in 5% hydrochloric acid medium. Recoveries of free MDA and tetramethoxypropane (used as an MDA precursor) in vegetable oils were satisfactory. During autoxidation, a remarkable difference between the DP values of methyl oleate, methyl linoleate and some vegetable oils, and that of methyl linolenate was observed. Only methyl linolenate released MDA during autoxidation. For autoxidised methyl linolenate the DP value correlated with the thiobarbituric acid(TBA) value, although the DP value was only 30% of the TBA value.  相似文献   
6.
Proteinase A, excreted from yeast cells into beer during fermentation in the brewing process, has been shown to degrade foam-active proteins and to decrease foam stability. In order to improve the measurement of this enzyme in beer, a new fluorescent peptide, MOCAc-Ala-Pro-Ala-Lys-Phe-Phe-Arg-Leu-Lys (Dnp)-NH2, was synthesised and applied to the accurate and rapid estimation of proteinase A in commercial beer and fermenting wort. This novel substrate is several hundred times more sensitive to proteinase A than other previously reported synthetic substrates or native protein substrates. The concentration of proteinase A in beer is closely related to foam stability and proteinase A activity was found to increase gradually during fermentation. The concentration of proteinase A excreted from yeast cells is also closely related to the vitality of pitching yeast cells. This new method was successfully applied to the evaluation of yeast vitality and the development of optimum yeast handling procedures.  相似文献   
7.
Crack-tip dislocations in silicon crystals have been examined by using high-voltage electron microscopy. Cracks were introduced by the Vickers indentation method at room temperature and the indented specimens were annealed at high temperatures to induce dislocations around crack tips under the presence of residual stress due to the indentation. A selected area around a crack tip was thinned by a focused ion beam (FIB) technique. Specimens were thinned in advance by a twin-blade cutting (TBC) method, which is a simple cutting process for saving FIB machine time. A combination of FIB and TBC can be a useful thinning procedure for the efficient preparation of transmission electron microscopy specimens. Characteristic dislocation structures were observed around the tip of a crack, aiding the elucidation of dislocation processes, which is essential to increase the fracture toughness of materials.  相似文献   
8.
Universal filter using plus-type CCIIs   总被引:1,自引:0,他引:1  
A universal second-order filter circuit with voltage gain using only plus-type current conveyors (CCIIs) is presented. The circuit offers several advantages, such as high input impedance, low filter sensitivities to passive elements, use of grounded capacitors and independent control of ω0, Q and voltage gain with separate grounded resistors. The use of only one type (plus-type or minus-type) of CCII simplifies the configuration  相似文献   
9.
In 1996 a conversion efficiency of 17.1% had been obtained on 15 cm×15 cm mc-Si solar cell. In this paper, large-scale production technology of the high-efficiency processing will be discussed. Enlarging reactive ion etching (RIE) equipment size, technology of passivation, and fine contact grid with low resistance by screenprinted metallization, which is firing through PECVD SiN, have been investigated.  相似文献   
10.
The 35 nm gate length CMOS devices with oxynitride gate dielectric and Ni salicide have been fabricated to study the feasibility of higher performance operation. Nitrogen concentration in gate oxynitride was optimized to reduce gate current I/sub g/ and to prevent boron penetration in the pFET. The thermal budget in the middle of the line (MOL) process was reduced enough to realize shallower junction depth in the S/D extension regions and to suppress gate poly-Si depletion. Finally, the current drives of 676 /spl mu/A//spl mu/m in nFET and 272 /spl mu/A//spl mu/m in pFET at V/sub dd/=0.85 V (at I/sub off/=100 nA//spl mu/m) were achieved and they are the best values for 35 nm gate length CMOS reported to date.  相似文献   
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