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81.
The goal of this paper is to augment the ordinal temporal-difference type (TD-type) reinforcement learning model in order to detect the most suitable learning model of the human decision-making process in financial investment tasks. The simplicity and robustness of the TD-type learning model is fascinating. However, the available evidence and our observation suggest the necessity of introducing the nonlinear effect in learning and the possibility that additional factors might play important roles in the investment decision-making process. To extend the ordinal TD-type learning model, we adopt a three-layered perceptron as the basis function and the hierarchical Bayesian method to calibrate the parameter values. The result of the predictive test suggests that the augmented TD-type learning model constructed in this paper can evade the overfitting and can predict people's investment behavior well as compared to other familiar learning models. 相似文献
82.
Previous work has shown that male sorghum plant bugs, Stenotus rubrovittatus (Matsumura) (Heteroptera: Miridae), are more attracted to young virgin females than to old virgin females and are not attracted
to mated females. Therefore, we examined the effects of age and mating status on female sex pheromone levels. The pheromone
components, hexyl butyrate, (E)-hex-2-en-1-yl butyrate, and (E)-4-oxohex-2-enal, were collected from females in two different ways. First, the compounds were extracted from whole bodies
of each female and quantified by gas chromatography-mass spectrometry (GC-MS). Pheromone levels extracted from virgin female
bodies decreased with age. In females that had just mated, pheromone levels did not differ from those of virgin females, and
pheromone levels in mated females remained relatively constant up to 15 d after mating. This absence of change in pheromone
levels extracted from whole bodies of mated females is not congruent with previous reports of lack of male attraction to these
females. In a second method for pheromone recovery (adsorption on a PDMS-coated stir bar), GC-MS analysis showed that mated
females released lower amounts of pheromone components compared to those emitted by virgin females of the same age (4 d).
As was the case with whole body extracts, young virgin females (3 d) released higher amounts of pheromone components than
did old virgin females (8 d). The results suggest that male response in S. rubrovittatus is dictated more by the quantities of pheromone components released into the volatile headspace by females than by the quantities
present in the body. 相似文献
83.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献
84.
Hideki Tanaka Daisuke Noguchi Akiko Yuzawa Tetsuya Kodaira Hirofumi Kanoh Katsumi Kaneko 《Journal of Low Temperature Physics》2009,157(3-4):352-373
We have investigated the applicability of simulations and theoretical techniques for exploring the selectivities of hydrogen isotopes. We have simulated the adsorption isotherms of H2 in an idealized carbon slit pore at 77 K by using the grand canonical Monte Carlo simulations with the Feynman-Hibbs effective potential (FH-GCMC) and the rigorous path integral method (PI-GCMC), and we obtained good agreement between the isotherms from both simulations. This suggests that FH-GCMC, which uses the approximative Feynman-Hibbs treatment, is as useful as PI-GCMC for exploring H2 adsorption at 77 K. Moreover, we show that the ideal adsorption solution theory (IAST) can predict the selectivity of D2 over H2 in the interstices of single-wall carbon nanotube (SWNT) bundles at 77 K (below 0.1 MPa) very well by comparing the obtained results with the mixture adsorption FH-GCMC simulations. This indicates that IAST is also applicable to the estimation of the selectivity of D2 over H2 at moderate pressures and at 77 K from experimental single-component adsorption isotherms. We also demonstrate that the FH-GCMC simulation can reproduce the experimental adsorption isotherms of H2 and D2 in aluminophosphate AlPO4-5 at 77 K. Finally, we analyze the selectivity of D2 over H2 by IAST with the experimental single-component adsorption isotherms of H2 and D2 at 77 K for a variety of adsorbents: AlPO4-5, activated carbon fibers (ACFs), HiPco SWNT, and SWNHs. The selectivities predicted by the experimental adsorption data based on the results from the FH-GCMC simulations are presented and discussed. 相似文献
85.
Crack tip opening displacement (CTOD) has been calculated using the plastic hinge model with an assumed rotational center since the British Standards Institution (BS) standardized BS5762 in 1979. The American Society for Testing and Materials (ASTM) accepted the plastic hinge model and standardized E1290 in 1989. However, ASTM revised E1290 in 2002, and has proposed a conversion from J to CTOD. CTOD-based fracture toughness evaluation has been widely used for the defect assessment of many welded structural components, and two different CTOD calculations could lead to confusion for Fitness-for-Service. In this study, the effects of CTOD testing methodologies on CTOD values were investigated according to round robin tests conducted by the Japan Welding Engineering Society (WES), and the concept of CTOD as a fracture parameter is discussed. 相似文献
86.
Nanoparticles of Pd-Sn were prepared under various conditions by applying ultrasonic irradiation, and their electrocatalytic activity for oxygen reduction was evaluated in 0.5 M KOH. The average size of Pd-Sn nanoparticles thus prepared was about 3-5 nm. The Pd in Pd-Sn nanoparticles was found to be mostly in the metallic state. The electrocatalytic activity of the Pd-Sn nanoparticles for the oxygen reduction reaction (ORR) is greater than Pt or Pd nanoparticles in alkaline media. The molar ratio of Pd to Sn metal ions in the synthesizing solution, their initial concentrations, the concentration of ethanol, which increases primary hydrogen radicals during sonolysis, and the concentration of citric acid were found to affect the size distribution of the Pd-Sn nanoparticles, and therefore, those factors controlled the electrocatalytic activity for ORR. Particularly, the concentration of citric acid was found to be important for controlling the surface property on Pd-Sn particles to adjust the electrocatalytic activity for ORR. 相似文献
87.
Shindo T Ushiyama H Kan K Uehara S Yasuda K Takano I Saito K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(3):122-126
The contents of barbaloin (BA), isoBA, aloin-dimers A, B, C, D and aloe-emodin (AE) in aloe drinks were investigated. BA and isoBA were detected in 30 of the 31 samples at the levels of 120-570 micrograms/mL and 120-580 micrograms/mL, respectively. Aloin-dimers A, B, C and D were detected in 8 of the 31 samples at the levels of 12-38 micrograms/mL, 13-39 micrograms/mL, 11-36 micrograms/mL and 16-69 micrograms/mL, respectively. AE was detected in all of the 31 samples at the levels of 0.03-1.3 micrograms/mL. When aloe drinks were stored for 4 weeks at 5 degrees C after opening the bottle, decrease of BA and isoBA, and increase of AE and aloin-dimers A, B, C and D were observed in most cases. However, in a few aloe drinks, all of BA, isoBA, aloin-dimers A, B, C, D and AE decreased. In these drinks, the existence of aloin-trimer was elucidated by LC/MS analyses. These data suggested that BA in aloe drinks is converted to the dimer and then to the trimer during storage. 相似文献
88.
Mercury and selenium concentrations in the internal organs of toothed whales and dolphins marketed for human consumption in Japan 总被引:3,自引:0,他引:3
Small cetaceans (toothed whales odontoceti and dolphins delphinidae) have been traditionally hunted along the coast of Japan and fresh red meat and blubber, as well as boiled internal organs such as liver, kidney, lung and small intestine, are still being sold for human consumption. We surveyed mercury contamination in boiled liver, kidney and lung products marketed in Japan between 1999-2001. The average +/- S.D. of total mercury (T-Hg) was 370 +/- 525 (range: 7.60 approximately 1980, n = 26) microg/g in liver, 40.5 +/- 48.5 (7.30-95.1, n = 15) microg/g in kidney and 42.8 +/- 43.8 (2.10-79.6, n = 23) microg/g in lung. A high correlation was observed between T-Hg and selenium (Se) concentrations in these organs, supporting the formation of a Hg-Se complex. The formation of a Hg-Se complex probably contribute to the detoxification of Hg for cetaceans and allows a very large accumulation of Hg in livers. The provisional permitted level of T-Hg in marine foods set by the Japanese Ministry of Health and Welfare is 0.4 microg/ g, and the provisional permitted weekly intake (PTWI) set by WHO is 5 microg/kg bw/week. The maximal T-Hg detected in boiled liver (1,980 microg/g) exceeds the permitted level by approximately 5,000 times and the consumption of only 0.15 g of liver exceeds the PTWI of 60 kg of body weight of the consumer, suggesting the possibility of an acute intoxication by T-Hg even after a single consumption of the product. 相似文献
89.
Adrenomedullin (AM) was originally characterized in extracts of an adrenal medullary tumor. Since this original finding the peptide and its mRNA have also been found in the adrenal cortex, specifically, in the cells of the aldosterone-secreting zona glomerulosa. It is clear that the synthesis of AM is actively regulated in both cortex and medulla. Much research effort has been focused on identifying a role for AM in the adrenal gland. To date, no consistent effect on medullary catecholamine biosynthesis has been demonstrated. In the cortex the actions of AM are controversial and appear to depend on both the tissue preparation used and on the specific receptor population expressed in the individual gland. The results of further studies on the long-term actions of AM on adrenal growth and differentiation are awaited with interest. 相似文献
90.
We describe the transient-state, multiple-species biofilm model (TSMSBM), which is a novel synthesis of key modeling features needed to describe multiple-species biofilms that experience time-varying conditions, particularly including periodic detachment by backwashing. The TSMSBM includes six features that are essential for describing multiple-species biofilms that undergo changes over time: (1) four biomass types: heterotrophs, ammonia oxidizers, nitrite oxidizers, and inert biomass; (2) seven chemical species: input biodegradable organic material (BOM), NH4(+)-N, NO2(-)-N, NO3(-)-N, utilization-associated products, biomass-associated products, and dissolved oxygen; (3) eight reactions that describe the rates of consumption or production of the different species, as well as the stoichiometric linkages among the rates; (4) reaction with diffusion of all the soluble species in the biofilm; (5) growth, decay, detachment, and flux of each biomass type by location in the biofilm; and (6) constant or periodic detachment of biofilm, both of which allow for protection of biomass deep inside the biofilm. The last two features of the TSMSBM provide novel additions to biofilm modeling, and the synthesis of all features is a unique advancement. A series of examples illustrates insights that the TSMSBM can provide about the transient development of multiple-species biofilms; the roles of soluble microbial products and detachment in controlling the distribution of biomass types and process performance; and how backwashing affects the biofilm in drinking-water biofiltration. 相似文献