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211.
Abstract— The temperature dependence of residual DC voltage was studied based on the adsorption and desorption of ions in the liquid‐crystal (LC) layer to and from the interface between the LC and alignment layers during the application of an external DC offset voltage. The relaxation process of the adsorbed ions during the open‐circuit state was also studied after applying the DC offset voltage. Those processes were found to follow the Arrhenius rule, and a new evaluation parameter related to the temperature is proposed for the design of the LC and alignment‐layer materials.  相似文献   
212.
Recently, the technology of cultivation has been and continuous to be developed in the fisheries and the studies for a high production efficiency are widely conducted. The reaction of fishes under the sound should be studied in order to develop the fish tank with less factors of stress. In this paper, three-dimensional measurement system of the fish motion has been presented in order to study the relation of the fishes under the stimulating sound. Three kinds of fishes are used to detect the reaction against the sounds. Frequency analysis is executed by using the threedimensional position data. 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   
213.
Effects of intermittent presentation of odours on cognitive-motor performance and brain activity during mental fatigue were examined using event-related brain potentials. Participants performed a Go/NoGo task for 60 min, in both odour and air control conditions. The time-on-task reaction time increase was significantly smaller in the odour condition than in the air control condition. Go- and NoGo-P3 amplitudes were larger in the presence of odours than during the air control, during mental fatigue. There were no effects of odours on error negativity (Ne)/error-related negativity (ERN) amplitude and latency. These results suggest that the presence of intermittent odours improves attentional/effortful control of response selection, and that this effect mitigates the deterioration of cognitive-motor performance during mental fatigue. PRACTITIONER SUMMARY: The present study provides evidence for a potentially effective strategy, the use of odours, to mitigate deficits in cognitive-motor performance during time-on-task. The results show that the presence of intermittent odours is an efficient tool for maintenance of attention and reaction time during a prolonged task.  相似文献   
214.
Greenhouse gas emissions were measured from tropical peatlands of Kalimantan, Indonesia. The effect of hydrological zone and land-use on the emission of N2O, CH4 and CO2 were examined. Temporal and annual N2O, CH4 and CO2 were then measured. The results showed that the emissions of these gases were strongly affected by land-use and hydrological zone. The emissions exhibited seasonal changes. Annual emission of N2O was the highest (nearly 1.4 g N m–2y–1) from site A-1 (secondary forest), while there was no signi.cant difference in annual N2O emission from site A-2 (paddy field) and site A-3 (rice-soybean rotation field). Multiplying the areas of forest and non-forest in Kalimantan with the emission of N2O from corresponding land-uses, the annual N2O emissions from peat forest and peat non-forest of Kalimantan were estimated as 0.046 and 0.004 Tg N y–1, respectively. The emissions of CH4 from paddy field and non-paddy field were estimated similarly as 0.14 and 0.21 Tg C y–1, respectively. Total annual CO2 emission was estimated to be 182 Tg C y–1. Peatlands of Kalimantan, Indonesia, contributed less than 0.3 of the total global N2O, CO2 or CH4 emission, indicating that the gaseous losses of soil N and C from the study area to the atmosphere were small.  相似文献   
215.
In this paper, we address a new Lagrangian relaxation (LR) method for solving the hybrid flowshop scheduling problem to minimize the total weighted tardiness. For the conventional LR, the problem relaxing machine capacity constraints can be decomposed into individual job-level subproblems which can be solved by dynamic programming. The Lagrangian dual problem is solved by the subgradient method. In this paper, a Lagrangian relaxation with cut generation is proposed to improve the Lagrangian bounds for the conventional LR. The lower bound is strengthened by imposing additional constraints for the relaxed problem. The state space reductions for dynamic programming for subproblems are also incorporated. Computational results demonstrate that the proposed method outperforms the conventional LR method without significantly increasing the total computing time.  相似文献   
216.
提出一种适用于脆塑性复合材料的弹脆塑性本构模型,并将该模型引入复合材料结构的力学行为分析中,采用R.Hill的屈服准则,设计了一个完整的复合材料结构弹脆塑性数值计算格式,给出了实验以及计算结果。  相似文献   
217.
The excited-state structure of β-phase poly(9,9-dioctylfluorene) (F8) is investigated by means of optical absorption and electroabsorption spectroscopies in order to reveal the effect of β-phase formation on the excited-state structure in F8. The excited-state structure of β-phase F8 consists of six essential states, where two new Bu states are formed on the four essential states of α-phase F8. The two additional Bu states result from the energy splitting of the Bu states of α-phase F8, caused by intermolecular interaction in β-phase F8.  相似文献   
218.
Presented here is MPEG-2 AAC low complexity profile decoder software for a low-power embedded RISC microprocessor, NEC V830 (300 mW @133 MHz). Fast processing methods for IMDCT reduce execution time by 41% and help achieve real-time decoding of a 5.1-channel audio signal, while using only 64.7% of processor capacity.  相似文献   
219.
The grouping method for isolated strains from foods using single-strand conformation polymorphism (SSCP) after PCR amplification of a portion of 16S rDNA was developed. This method was able to group the strains from various food samples based on 16S rDNA sequence. As 97.8% of the isolated strains from various foods were grouped correctly, use of the PCR-SSCP method enables the prompt and labor-saving analysis of microbial population of food-derived bacterial strains. Advantages in speed and accuracy of bacterial population identification by the PCR-SSCP method have practical application for food suppliers and testing laboratories.  相似文献   
220.
The present work reports the self-ordered formation of nanotubular oxide layers on Ti-Ta alloys of different compositions (Ti-13Ta, Ti-25Ta, Ti-50Ta, and Ti-80Ta) by anodization in 1 M H2SO4 + 0.15 wt.% HF. Depending on the alloy composition, nanoporous or highly ordered nanotube structures can be formed. The homogeneity of the nanotubular surface layers is strongly affected by the microstructure of the alloys. Over a wide composition range the alloys exhibit a two-phase structure, and this results in two distinct tube morphologies formed on the different phases. In particular, on the chemically less stable phase, the top of nanotube layers is etched, which results in a disordered top morphology of the tubes on Ti-13Ta and Ti-25Ta, whereas this effect yields a difference in tube length on the two phases on Ti-50Ta. For the Ti-50Ta alloy, a bimodal self-organization can be observed, i.e. ordered patterns of oxide tubes with two distinct diameters are formed where larger tubes are surrounded by smaller tubes with a regularity that depends on the chemical composition of the two phases.  相似文献   
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