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11.
These days, the number of pharmaceutical patent applications which do not specify the principal active ingredient in the form of a chemical name or structure is increasing. These patents are difficult to retrieve in retrospective on-line searches using chemical structures or keywords. Furthermore, even if you could find them, the situation with regard to patentability is obscure and this causes considerable problems for the experts in charge of the patent search. If you are a searcher for a large pharmaceutical company, you might already be apprehensive of infringing such patents. We, the JFA,* gathered these patents together and studied the differences between their patentability in Japan, the US and the EPO.  相似文献   
12.
A development of 170GHz/500kW level gyrotron was carried out as R&D work of ITER. The oscillation mode is TE31,8. In a short pulse experiment, the maximum power of 750kW was achieved at 85kV/40A. The efficiency was 22%. In the depressed collector operation, 500kW/36%/50ms was obtained. The maximum efficiency of 40% was obtained at PRF=470kW whereas the power decrease by the electron trapping was observed. Pulse extension was done up to 10s at PRF=170kW with the depressed collector operation. The power was limited by the temperature increase of the output window.  相似文献   
13.
An experiment was carried out for transforming the 120 GHz-TE12.2 whispering-gallery mode (WGM) into a circularly polarized hollow radiation beam. A hollow beam was formed by reflecting the WGM, which was radiated from a 16 mm radius circular waveguide cut, with an annular mirror having suitable local normal vectors. The experimentally observed field intensity profiles of the reflected wave were in good agreement with calculated results.  相似文献   
14.
An implementation of the IF section of WCDMA mobile transceivers with a set of two chips fabricated in an inexpensive 0.35-/spl mu/m two-poly three-metal CMOS process is presented. The transmit/receive chip set integrates quadrature modulators and demodulators, wide dynamic range automatic gain control (AGC) amplifiers, with linear-in-decibel gain control, and associated circuitry. This paper describes the problems encountered and the solutions envisaged to meet stringent specifications, with process and temperature variations, thus overcoming the limitations of CMOS devices, while operating at frequencies in the range of 100 MHz-1 GHz. Detailed measurement results corroborating successful application of the new techniques are reported. A receive AGC dynamic range of 73 dB with linearity error of less than /spl plusmn/2 dB and spread of less than 5 dB for a temperature range of -30/spl deg/C to +85/spl deg/C in the gain control characteristic has been measured. The modulator measurement shows a carrier suppression of 35 dB and sideband/third harmonic suppression of over 46 dB. The core die area of each chip is 1.5 mm/sup 2/.  相似文献   
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16.
The implementation of time-domain diakoptics in the FDTD method   总被引:1,自引:0,他引:1  
The time-domain diakoptics is implemented in the finite-difference time-domain (FDTD) method with two types of connecting interfaces: i) directional interface (TLM-type), and ii) total-field interface (FDTD-type). The FDTD-type interface provides a more efficient way to realize time-domain diakoptics than TLM, especially for device optimization problems. To emulate the TLM-type interface in FDTD, two novel algorithms are developed in this paper. One is to implement an ultra-wideband absorbing boundary on the excitation plane during excitation. The other is to separate directional waves without the knowledge of incident waves. For a large circuit with cascaded modules, sequential and parallel algorithms are provided to connect them. With these connecting algorithms, time-domain diakoptics is one candidate method to realize modular and parallel computation in FDTD simulations. The validity of these algorithms is confirmed by comparison with simulated results from Microwave SPICE  相似文献   
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18.
As a room temperature bonding method, surface activated bonding (SAB) method has been introduced to be one of the most appropriate interconnection methods for the next generation of electronic packaging. Thus it is important to study the reliability of SAB interconnection in long term life test.In this paper, interconnections of Au bump and Cu film bonded by SAB method were performed in high temperature thermal aging test. Degradation of properties such as electrical resistance, shear strength of bump and interface microstructure during aging process were studied to investigate the failure mechanism of the interconnection. Intermetallic compound Cu3Au was found formed at the interface during thermal aging, and it causes evolvement of the properties and failure mode of the interconnection changing in shear test. Results reveal that SAB is suitable for the interconnection between Au bump and Cu film and it is reliable in thermal reliability test.  相似文献   
19.
Pure delay effects on speech quality in telecommunications   总被引:4,自引:0,他引:4  
The effect of transmission delay on speech quality in telecommunications is described, with human factors such as conversational mode and the talker's knowledge of the cause of delay taken into account. Objective quality estimation methods for delay effects are proposed, and these methods are applied in an actual communications network. In connection with delay perception in a telephone conversation, the assumption was verified that a talker expects a particular response time from a partner, and that delay that is outside this expectation time window is noticed. Taking this information into account, a subjective conversational experiment is controlled by six kinds of tasks by varying the temporal characteristics. Thus, a subjective assessment of delay effects is obtained by laboratory tests in relation to the detectability threshold, opinion rating, and conversational efficiency. Objective quality measures for each test were defined as a linear combination of temporal parameters that correspond closely to subjective qualities  相似文献   
20.
We report a dispersion slope equalizer on a planar lightwave circuit for wavelength division multiplexing (WDM) transmission. This device consists of an array of lattice-formed equalizers with different compensation values fabricated on one wafer and arrayed-waveguide gratings for wavelength multi/demultiplexing. We describe its configuration, operational principle, parameter design, fabrication, and measured characteristics in detail. N/spl times/20 and N/spl times/40 Gb/s slope equalizers were fabricated and their characteristics agreed well with designed values. We also report a reduction in the bias electrical power needed for thermooptic phase shifters in the equalizer array that we realized by employing a phase trimming technique normally used for optical switches.  相似文献   
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