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1.
The use of field robots can greatly decrease the amount of time, effort, and associated risk compared to if human workers were to carryout certain tasks such as disaster response. However, transportability and reliability remain two main issues for most current robot systems. To address the issue of transportability, we have developed a lightweight modularizable platform named AeroArm. To address the issue of reliability, we utilize a multimodal sensing approach, combining the use of multiple sensors and sensor types, and the use of different detection algorithms, as well as active continuous closed‐loop feedback to accurately estimate the state of the robot with respect to the environment. We used Challenge 2 of the 2017 Mohammed Bin Zayed International Robotics Competition as an example outdoor manipulation task, demonstrating the capabilities of our robot system and approach in achieving reliable performance in the fields, and ranked fifth place internationally in the competition.  相似文献   
2.
A technique to determine a trace amount of hydrogen in carbon materials heat-treated above 1000 °C was developed. Three types of carbons prepared from poly(furfulyl alcohol), poly(vinyl chloride) and mesophase carbon microbeads were heat-treated at various temperatures ranging from 1000 to 1800 °C. Then they were gasified by O2 in a fixed bed flow reactor, and the H2O gases formed during the gasification processes were carefully monitored with a Karl Fischer moisture analyzer. As a result, this method makes it possible to determine the hydrogen contents in the carbons down to three places of decimals as a weight percent and can detect even a trace amount of hydrogen as low as 0.002 wt.%. A possible chemical structure of carbon edge sites was also discussed based on the experimentally determined hydrogen contents.  相似文献   
3.
Phosphoinositides (PIs) play important roles in the structure and function of the brain. Associations between PIs and the pathophysiology of schizophrenia have been studied. However, the significance of the PI metabolic pathway in the pathology of schizophrenia is unknown. We examined the expression of PI signaling-associated proteins in the postmortem brain of schizophrenia patients. Protein expression levels of phosphatidylinositol 4-phosphate 5-kinase type-1 gamma (PIP5K1C), phosphatidylinositol 4-kinase alpha (PIK4CA, also known as PIK4A), phosphatase and tensin homolog deleted from chromosome 10 (PTEN), protein kinase B (Akt), and glycogen synthase kinase 3β (GSK3β) were measured using enzyme-linked immunosorbent assays and multiplex fluorescent bead-based immunoassays of the prefrontal cortex (PFC) of postmortem samples from 23 schizophrenia patients and 47 normal controls. We also examined the association between PIK4CA expression and its genetic variants in the same brain samples. PIK4CA expression was lower, whereas Akt expression was higher, in the PFC of schizophrenia patients than in that of controls; PIP5K1C, PTEN, and GSK3β expression was not different. No single-nucleotide polymorphism significantly affected protein expression. We identified molecules involved in the pathology of schizophrenia via this lipid metabolic pathway. These results suggest that PIK4CA is involved in the mechanism underlying the pathogenesis of schizophrenia and is a potential novel therapeutic target.  相似文献   
4.
To identify nitrobenzanthrones (NBAs) such as 3-nitro-7 H -benz[ de ]anthracene-7-one (3-NBA) on the basis of their electronic spectral data, we have synthesized 1-, 2-, 3-, 9-, and 10-NBAs and measured their absorption and emission spectra. The first strong absorption band of the NBAs appeared in the region 350-440 nm; the band of 10-NBA was red-shifted by about 20 nm. The molar absorptivities of 3- and 9-NBA were about two times as large as those of the others. The fluorescence spectra of the NBAs varied more largely with the position of the nitro group compared to the absorption spectra. The quantum yields of fluorescence were very small, ranging from ~10 m 2 for 2- and 10-NBA to ~10 m 4 for 1- and 3-NBA. 3-NBA exhibited a characteristic spectrum with two broad bands at 450 and 530 nm. On excitation causing an n ~ * transition in the NBAs, their fluorescence intensities increased by a factor of 10. Phosphorescence was observed at 77 K for all compounds though that of 1-NBA was very weak. These results give the promise of characterizing individual isomers of NBAs on the basis of their spectroscopic data.  相似文献   
5.
Wire-rate packet processing and its energy saving for over 100 Gbps speed of line are major issues to be resolved in optical packet switching (OPS) networks. For that purpose, we newly develop a high-speed, deterministic-latency electronic header processor based on longest prefix matching (LPM) for searching optical packet destination addresses (OP-DAs). This paper reports the successful experimental results of electronic header processing based on LPM search of up to 48 bits and optical switching of 100 Gbps optical packets by the use of the header processor. We demonstrate 48-bit LPM-capable optical packet switching. We also demonstrate IP packet transfer and 32-bit LPM-capable optical packet switching. In the latter demonstration, the 32-bit OP-DA of optical packets is directly copied from the 32-bit destination address of Internet Protocol version 4 (IPv4) packets. This result indicates that OPS networks can be deployed with electronic IP networks by the use of integrated network operation between OPS and IP networks.  相似文献   
6.
Very stable and small CdSe nanoparticles (NPs) were synthesized from the aqueous solutions containing L-cysteine (Cys) at room temperature. The Cys-capped CdSe NPs showed a very sharp excitonic peak at 420 nm. Its very small full width at half maximum (18 nm) indicates very high quality of the CdSe NPs. Their absorption features experienced little change over a month, implying an excellent stability of the CdSe NPs. The synthesis conditions were very critical to the optical property and stability of the CdSe NPs: only those prepared at specific conditions (n(Se-precursor)/n(Cd-precursor) = 0.25-0.5, n(Cys)/n(Cd-precursor) = approximately 9, pH = approximately 12) showed very sharp absorption peaks and maintained an excellent stability against time. Under these conditions, the peaks always appear at nearly the same wavelength, indicating that these NPs are selectively stable and grow at a particular size and structure.  相似文献   
7.
Chloro-7 H -benz[ de ]anthr-7-ones (chlorobenzanthrones) are useful as starting materials for synthesis of larger polycyclic aromatic compounds by means of condensation. In the synthesis, the position of the chlorine atom is very important because the structure of condensation products strongly depends on it. For this reason, we have synthesized several chlorobenzanthrones. Although 3- and 4-chlorobenzanthrone were prepared by direct chlorination of benzanthrone and by glycerol condensation of 2-chloroanthraquinone, respectively, the synthesis of 1- and 2-chlorobenzanthrone has not yet been successful. In the present study, we attempted to synthesize them by use of the Sandmeyer reaction. First, we nitrated benzanthrone with nitric acid; 1- and 2-nitrobenzanthrone were obtained by nitration in nitrobenzene at 50-60° and in glacial acetic acid at 105-110°, respectively. Then the nitroderivatives were reduced to corresponding aminoderivatives; the reduction was performed with sodium sulfide for 1-nitrobenzanthrone and with hydrogen chloride and tin for 2-nitrobenzanthrone. Finally, chlorination was carried out by use of the Sandmeyer reaction. The products were separated and purified by column-chromatography. The position of chlorination was confirmed by NMR spectroscopy.  相似文献   
8.
给出了一种用于复杂表面形状精密纳米加工的探针装置.该探针由一个高速可控的金刚石切割单元(FTC单元)和一个高灵敏度的压电式力传感器组成.而FTC单元由一个单点金刚石切割工具和一个压电陶瓷晶体(PZT)驱动器构成.压电陶瓷晶体(PZT)驱动器可对与切削量相对应的金刚石工具的Z向位置进行高速控制,从而实现加工复杂表面形状的目的.加工中的切削力是反映切削进程的重要指标,可由联结于FTC单元的高灵敏度力传感器进行测量.比对了用于联结力传感器和FTC单元的两种设计方法.  相似文献   
9.
The fibers in injection molded FRP provide the material's strength and stiffness; however, they also supply many of the problems. Preferential orientation of fibers during molding can reduce strength and stiffness below expected values in critical directions, or induce warpage in thin walled sections. Makers of short fiber reinforced injection molded products typically use computer aided engineering packages to optimize product performance and manufacturing variables. However, the reliability of the fiber orientation simulation can be limited, and the method is not easily understood, making an assessment of accuracy for a given situation difficult. In addition, the structural module of flow analysis packages is often a basic package with many features missing. This paper presents a structural analysis system for injection molded parts made of short fiber reinforced plastics. A full-featured commercial structural analysis code is interfaced with a flow analysis program using a practical material model that takes into account the effects of local fiber orientation. The system is completely open to the user, and can be modified as required.  相似文献   
10.
Reaction time (RT) in a detection or a location discrimination task increases when a target is repeatedly presented at the same location (inhibition), whereas RT decreases in feature (color or orientation) discrimination tasks (facilitation; Y. Tanaka & S. Shimojo, 1996a). Here, the time course of inhibition and facilitation was examined, using a repetition priming paradigm. Results indicate that inhibition occurred only in the immediately successive trial, whereas facilitation accumulated over several trials with location repetition. Moreover, inhibition and facilitation occurred in a task-relevant manner: Detection–location discrimination tasks produced transient RT increase, whereas feature discrimination tasks produced cumulative RT decrease. These results suggest a functional dissociation between spatial orienting and feature analysis, as well as top-down modulations by tasks leading to different types of visual memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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