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排序方式: 共有95条查询结果,搜索用时 62 毫秒
1.
In coating and gravure printing, an impinging jet nozzle with high thermal efficiency for drying of coated film was developed.

Trial production 0f 40 kinds of nozzle enables to develop a high-performance impinging jet nozzle with heat transfer coefficient 1.5 times larger than that of current slit nozzle, through measurement of heat transfer coefficient, visualizations of air flow and heat transfer, and measuremenu of jet velocity and turbulence distribution. The purpose of the trial production was to expand a range of high heat transfer and promote turbulence compared with the current nozzle.

Paying attention to mass transfer within gravure ink coated film, drying characteristic of the film was analyzed by numerical solution of a set of equations governing the drying process in which concentration dependencies 0f the diffusion coefficient and the equilibrium vapor pressure were considered.

Applying these analyses. an industrial scale dryer with excellent drying efficiency has finally been developed.  相似文献   
2.
Bulk metallic glasses (BMGs) have potential applications for both structural and functional components owing to their good mechanical properties. With the aim of demonstrating great engineering value of BMGs, a direct melt-forming technique based on suction casting for the production of glassy alloy tubes was developed. The fabrication, structure, geometry, properties and sensor performance of the tubes were examined. The results show that the Coriolis mass flowmeters using the Ti-based glassy alloy sensor tube exhibit excellent measurement sensitivity, viz. 28.5 times higher than that of the conventional flowmeter manufactured using stainless steel (SUS316) tube.  相似文献   
3.
An obstacle avoidance scheme of a two-wheeled mobile robot is shown by selecting an appropriate Lya- punov function. When considering the obstacle, the Lyapunov function may have some local minima. A method which erases the local minima is proposed by using a function which covers the minima with a plane surface. The effectiveness of the proposed method is verified by numerical simulations.  相似文献   
4.
The authors have proposed the signal decomposition technique as one of the powerful solution to mitigate the large peak‐to‐average power ratio (PAPR) to be addressed in orthogonal frequency division multiplexing (OFDM) transmitters especially on mobile terminals. In order to enhance the receiver SNR, the simple noise elimination techniques working together with the signal decomposition technique have also been proposed that eliminates the noise added on the decomposed constant amplitude on‐off‐signals taking advantage of the knowledge of their constant amplitude at the receiver. In this paper, we discuss the parameter design issue of the proposed techniques and their optimization. Then, demonstrate the PAPR, the power‐added efficiency (PAE), and also the BER performances operating on the optimized parameters. It is confirmed that the proposed signal decomposition technique improves the PAPR by 4 dB and doubles the PAE at the complementary cumulative distribution function of 1%. It is also confirmed that the proposed noise elimination technique improves the receiver SNR by 3 dB at the BER of 10 to 3, which is nearly equal to that of conventional OFDM, under the conditions that the decomposed signals are transmitted over the independent additive white Gaussian noise channels. Furthermore, it is demonstrated that the proposed techniques work properly when the decomposed signals are transmitted over 2 × 2 multi‐input multi‐output.  相似文献   
5.
Frequency response analysis (FRA) is a powerful technique to detect internal abnormalities within power transformers. However, diagnosis criteria of power transformers by FRA have not been fully established yet. In this paper, a new evaluation method of degree of identification between two transfer functions is proposed. In the proposed method, a frequency window is employed and cross‐correlation factor is calculated with moving the window. Furthermore, the proposed method is applied to transfer functions of real transformers with or without some abnormalities. Based on this discussion, objective criteria for diagnosis of abnormalities of transformer windings by FRA are proposed. The proposed criteria are based on a few data of transformers with some abnormalities. Therefore, the proposed criteria are tentative and they would be improved by accumulation of further data.  相似文献   
6.
Dry electrodes of a smart shirt for measuring biological signals were prepared by the additive printing method using a stretchable conductive paste with Ag fillers loading. Interfacial impedance between the electrode and skin depended on the contact pressure of electrode and the moisture of stratum corneum. When moisture of stratum corneum was more than 30%, ECG could be measured using the stretchable electrodes printed on a compression shirt. However, noise signal in the ECG signal increased when the moisture of stratum corneum was less than 30%. To solve this problem, we propose to use additional electrodes made of an electrically conductive kneaded rubber.  相似文献   
7.
It is of prime importance to maintain voltage profile within the proper range in distribution systems with a large amount of photovoltaics and electric vehicles (EVs). In particular, there is a possibility that line drop compensation (LDC) logic, which is utilized for the control of load ratio tap transformer (LRT) does not work properly when reverse power flow is included partially. Hence, in this paper, we have developed a new LRT control method based on the sensor information supposing that some section switchgears with sensors are introduced in the future distribution systems. Specifically, the extreme value of voltage profile is estimated by convergence calculation in the section between the section switchgear with sensor and LRT. Moreover, the voltage at the end node can be estimated by LDC method using sensor information of section switchgear. The proposed method was tested using a distribution system model and its effectiveness was shown.  相似文献   
8.
The synergistic effect of methyltrioctylammonium chloride (QCI) on the extraction of Np(V) by 1-phenyl-3-methyl-4-benzoyl-pyrazolone(HP) in benzene is studied over the pH range 2-6. This system extracts Np(V) better than any previously reported. The interaction of the extractants and monomer-dimer equilibria affect the distribution behavior of Np(V) in a complicated manner. Analysis of the results suggests that NpO2 + (M+) is extracted as mixed dimers, (QMP2QCl)o and (QMP2QP)o.  相似文献   
9.
ABSTRACT

Two types of alkylcalix[4]arene carboxylates with different alkyl chains, together with three types with the same alkyl chains were synthesized to investigate their solubility in four different organic diluents. The solubility was found to be enhanced by using the calixarene compounds with longer alkyl chains and by using mixtures of compounds with different alkyl chains. The order of solubility in the different organic diluents was found to be:

chloroform > toluene ? EXXSOL D80 ≈ hexane.

The stoichiometry of the copper complex with the compounds having the same alkyl chains was also determined and the maximum loading capacity of copper with each extractant was estimated.  相似文献   
10.
Effects of Bismuth Sesquioxide on the Characteristics of ZnO Varistors   总被引:3,自引:0,他引:3  
The nonlinearity of ZnO varistors is significantly influenced by the Bi2O3 and Sb2O3 contents, as well as by the phase composition of the Bi2O3. Degradation of the current-voltage characteristics due to the applied voltage is not always lowered by the β—γ transition of the Bi2O3 phase. Lattice parameter determinations and stress analyses suggest that the Bi2O3-rich phase in multigrain junctions causes mechanical strain at the grain boundary which may play an important role in the current-voltage characteristics of ZnO varistors.  相似文献   
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