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61.
We investigated the population dynamics of a tritrophic interaction mediated by herbivore-induced plant volatiles that attracted
carnivorous natural enemies of herbivores. We modeled the system by abstract chemistry, and an abstract rewriting system of
multisets (ARMS), and compared the case where plants produced herbivore-induced volatiles with the case where they did not.
We found that there was a case where herbivore-induced volatiles that attract carcivores resulted in a population increase
of herbivores.
This work was presented, in the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January 15–17,
2001 相似文献
62.
Ide N. Fukuhisa H. Kondo Y. Yoshida T. Nagamatsu M. Junji M. Yamazaki I. Ueno K. 《Solid-State Circuits, IEEE Journal of》1993,28(3):352-361
A CMOS pipelined floating-point processing unit (FPU) for superscalar processors is described. It is fabricated using a 0.5 μm CMOS triple-metal-layer technology on a 61 mm2 die. The FPU has two execution modes to meet precise scientific computations and real-time applications. It can start two FPU operations in each cycle, and this achieves a peak performance of 160 MFLOPS double or single precision with an 80 MHz clock. Furthermore, the original computation mode, twin single-precision computation, double the peak performance and delivers 320 MFLOPS single precision. Its full bypass reduces the latency of operations, including load and store, and achieves an effective throughput even in nonvectorizable computations. An out-of-order completion is provided by using a new exception prediction method and a pipeline stall technique 相似文献
63.
Shuzo Hattori Shinzo Morita Masao Yamada Junji Tamano Masayuki Ieda 《Polymer Engineering and Science》1983,23(18):1043-1046
This paper presents the preliminary results of efforts to improve dry processed electron beam resist materials using plasma polymerization coating technology. Three approaches investigated were chemical susceptibility modification, the use of multilayer resist structures, and the effect of grafting reactions. 相似文献
64.
65.
Poly(γ-benzyl L-glutamate) film composed of unusual 7-residue 2-turn (7/2) helices was prepared by slow casting from chloroform solution. The 7/2 helical conformation was irreversibly transformed at 84°C to the normal 18/5 conformation. In d.s.c. thermograms the transformation appeared as an endothermic first order transition with an enthalpy change of 3.4 cal g−1. The viscoelastic and dielectric measurements indicated that the loss peak due to the side chain motion in this film was reduced to a great extent compared to the film of 18/5 helices. The dielectric relaxation strength dictated that there was a motional restriction in three quarters of the side chains. By comparison to a racemic mixture of poly(γ-benzyl glutamate), these anomalous properties were attributed to the stack of terminal benzyl groups of side chains (ormed in an alternating manner between neighbouring chains). The first order transition arises from the cooperative fusion of the stack and the side chains with their benzyl groups which are restricted in thermal motion. Such stacks may be facilitated by the precise ‘knob (side chain) and hole (space between side chains)’ packing which can be attained between neighbouring 7/2 helices. 相似文献
66.
Junji Furukawa 《Polymer Bulletin》1982,7(1):31-37
Summary A theory of pseudo cross-link model suggests the existence of multiple links of various size composed of 116 segmental units. They possesses the heat and entropy of various magnitude giving various transition temperature, TA for the cross-link composed of 4 segments and TB for that of 16 segments. The glass-transition point Tg and the melting point Tm are defined by the different size of lateral multiple links. Relationships, Tm = 2 TA and Tg = (2/3)Tm = (4/3)TA, are derived. A wedge-type relaxation spectrum is obtained as a distribution of size of cross-links. For temperature dependence the WLF-equation is obtained. 相似文献
67.
Heat of mixing for ammonium chloride in liquid ammonia at 25°C was determined in the concentration range 0-50 wt% NH4Cl. It was calculated from the differential heat of solution observed in this work and the differential heat of dilution estimated from activities of solvent. A twin isoperibol calorimeter consisting of two stainless Dewar vessels was used at a relatively high pressure (up to 1.5 MPa). The accuracy of this calorimetry was examined by measuring the heat of solution for tris-(hydroxymethyl)aminomethane(THAM) in 0.1 kmol/m3 HCl at 25°C, and satisfactory agreement within 1.1% between experimental and literature value was obtained. The reproducibility for the experiment was within 2.8%. 相似文献
68.
Morita Shigeru Fujita Junji 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,9(4):713-723
X-ray spectra for several elements have been observed from a high-temperature plasma produced in a vacuum spark using a curved-crystal spectrometer. The transition wavelengths of the He-like resonance lines for Ti through Zn are determined for the first time under careful experimental treatments. The result is compared with theoretical predictions. The transition wavelengths of the Fe He-like resonance series lines up to 1s6p–1s2 and the Kβ transition energies of Ti partially M-shell-ionised ions (Ti VI–XIII) are also determined. As a result, several satellite lines are found. 相似文献
69.
Forsberg F Liu JB Shi WT Furuse J Shimizu M Goldberg BB 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(4):581-583
Changes in ambient pressure affects the reflectivity of ultrasound contrast microbubbles leading to an excellent correlation between subharmonic signals and hydrostatic pressure. The aortas of two dogs were scanned with an experimental pulse-echo system to validate in vivo pressure estimation based on subharmonic microbubble signals. Results matched well with instantaneous pressure measurements (from 20-60 mmHg) obtained simultaneously with a pressure catheter (root mean square errors <27%). 相似文献
70.
Anisotropy of styrene–butadiene rubber (SBR) was investigated. The anisotropy of the copolymer varies linearly with the styrene content and the ultimate value coincides with that of polystyrene at elevated temperature. From these facts, the transverse configuration of the pendant phenyl group is estimated irrespective of the styrene content of SBR. 相似文献