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981.
In this paper, we propose the system that combines the sensor network with the mail delivery system to construct the system that observes an environmental change of the broiler-house. As a result of hearing of the producer, the environment system needs to able to be observed some broiler-houses, to inspect the summary data from the cellular phone, and to transmit the warning mail in a rapid temperature change. A basic part of the system is a sensor network by the sensor module that we developed. Only the sensor modules are put in the each broiler-house, and the network by wireless LAN communication is constructed, because the system needs to watch of two or more broiler-houses, and it is difficult to setup a large-scale system at the broiler-house. The always-connected high-speed Internet is preferable to accumulate, to process data, and to offer it to the user in a comprehensible form. But, it is difficult to build always-connected high-speed Internet at the chicken farm which is used by experiment. The server is set up in the remote place, and we propose the system that delivers data from the chicken farm with mail. The verification of the effectiveness of the proposed system and the problem are examined by actually setting up the system that proposes it in the broiler-house, and operating it. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
982.
An ecosystem, especially a food web, is essentially characterized as a many-body system in which the members interact with each other under the limitations of the energy and resources. We introduce a coevolutional population dynamics model for food webs which contains energy-conserving interactions, energy dissipation, and rules for changing the degrees of freedom (extinction and mutation). In this model, the diversity of the system increases spontaneously. The statistical properties of the system, such as the distribution of the life time of the species, are also discussed. This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January 15–17, 2001  相似文献   
983.
The resistive transition to the superconducting (SC) state in -(ET)2NH4Hg(SCN)4 was studied under magnetic fields applied parallel to the conducting plane. The SC state is divided into three regions: (1) temperature-dependent resistive region, (2) zero-resistive region, and (3) temperature-independent resistive region. We observed twofold symmetry in the resistance under an in-plane magnetic field near the midpoint of the SC transition, which indicates that the upper critical field 0 H c2 has the same twofold symmetry. This in-plane anisotropy can be ascribed to the crystal structure.  相似文献   
984.
The field orientation control of current source inverter (CSI) drive induction motor (IM) systems has been known to give an induction motor dc motorlike characteristics. As a result of an analysis, the characteristic of these systems does not necessarily coincide with that of dc motor systems, especially with light loads. The result of the analysis is verified by experiments.  相似文献   
985.
By dividing a water‐treed XLPE sheet sample of 1 mm thickness into a nondegraded region and a water‐treed one, relative permittivity and AC conductivity σAC2 of the water‐treed region have been estimated using an equivalent circuit. The variation of and σAC2 with the length r of the water‐treed region has been discussed based on the Sillars model. It was concluded that the volume fraction of water in the water‐treed layer is in the range from 0.5% to 1.5% for the most‐degraded XLPE sheet, which depends on the ratio of axes of spheroids to which water‐filled voids and channels are compared. It was also concluded that the AC conductivity of water in the water‐treed region ranges from 3 × 10?3 S/m to 2 × 10?2 S/m. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 148(3): 7–14, 2004; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10332  相似文献   
986.
Abstract— Column spacers were manufactured by a roll‐to‐roll process for a flexible plastic substrate and an LCD prototype was demonstrated for the first time. The purpose of this paper is to obtain a stable cell gap for plastic LCDs by designing the column spacers. The optimum condition was derived for the properties of the column spacers parameters, such as the cross section, density, and hardness. As a result, we could determine the optimum elastic modulus of the column spacers needed in order to precisely maintain the cell gap of the LCD as well as that of conventional glass plates, resulting in a uniform display luminance.  相似文献   
987.
The authors have introduced an automaton on a two-dimensional tape, which decides acceptance or rejection of an input tape by scanning the tape from various sides by three-way (deterministic and nondeterministic) finite automata, and have investigated the accepting powers. This paper continues the investigation of this type of automata, which consists of four three-way two-dimensional alternating finite automata (tr2-afa’s). We first investigate a relationship between the accepting powers of ∨-type automata (obtained by combining tr2-afa’s in ‘or’ fashion) and ∧-type automata (obtained by combining tr2-afa’s in ‘and’ fashion), and show that they are incomparable. Then, we investigate a hierarchy of the accepting powers based on the number of tr2-afa’s combined. Finally, we briefly describe a relationship between the accepting powers of automata obtained by combining three-way two-dimensional nondeterministic and alternating finite automata.  相似文献   
988.
Carboxyl-terminated single-walled carbon nanotubes (SWNTs) were successfully immobilized from solution phases onto the apexes of gold tips for scanning tunneling microscopy (STM). Gold STM tips were first modified with self-assembled monolayers of 4-mercaptobenzoic acid, and its carboxyl groups were used to anchor carboxylated SWNTs through Zn2+ ion-bridged coordination. These SWNT tips gave high-resolution STM images of a diether monolayer formed on the graphite surface. In addition and more importantly, the ether oxygens of the sample molecules were selectively observed as bright spots with the SWNT tips with significantly high reproducibility, which is due to the facilitation of electron tunneling through hydrogen bond interactions between the ether oxygens and carboxyl groups at the end of the SWNT tips.  相似文献   
989.
Abedin KS  Haidar S  Konno Y  Takyu C  Ito H 《Applied optics》1998,37(9):1642-1646
Mid-infrared radiation in the 5-18-mum range has been obtained by difference frequency generation in a AgGaSe(2) crystal by pumping with the output of a type I LiNbO(3) optical parametric oscillator (OPO). Here we suggest the use of a LiTaO(3) retarder to achieve an orthogonal state of polarization between OPO outputs that are necessary for efficient pumping of a AgGaSe(2) crystal. Several tens of kilowatts of peak power near 8 mum and continuously tunable operation in the above range have been obtained.  相似文献   
990.
Ueda M  Shiono T  Ito T  Yokoyama K 《Applied optics》1998,37(7):1165-1170
We have developed a diffractive micromachined chopper (DMC) for an IR wavelength of ~10 mum. This device operates mechanically by movable reflection grating beams. It modulates the diffraction efficiency by controlling the displacement of grating beams by an electrostatic force. For a CO(2) laser beam, a high modulation efficiency of 84% with an -0.8-dB small insertion loss was obtained by detecting 0th-order diffracted light. A novel pyroelectric IR microsensor with a DMC and a diffractive multilevel Si microlens was proposed and it demonstrated the detection of human existence.  相似文献   
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