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1.
The World robot summit disaster robotics category – achievements of the 2018 preliminary competition
Satoshi Tadokoro Tetsuya Kimura Masayuki Okugawa Katsuji Oogane Hiroki Igarashi Yoshikazu Ohtsubo 《Advanced Robotics》2019,33(17):854-875
The World Robot Summit is a robot Olympics and aims to be held in a different country every four years from 2020. The concept of the Plant Disaster Prevention challenge is daily inspections, checks, and emergency response in industrial plants, and in this competition, robots must carry out these types of missions in a mock-up plant. The concept of the Tunnel Disaster Response and Recovery challenge is emergency response to tunnel disasters, and is a simulation competition whereby teams compete to show their ability to deal with disasters, by collecting information and removing debris. The Standard Disaster Robotics challenge assesses, in the form of a contest, the standard performance levels of a robot that are necessary for disaster prevention and emergency response. The World Robot Summit Preliminary Competition was held at Tokyo Big Sight in October 2018, and 36 teams participated in the Disaster Robotics Category. UGVs and UAVs contended the merits of new technology for solving complex problems, using core technologies such as mobility, sensing, recognition, performing operations, human interface, autonomous intelligence etc., as well as system integration and implementation of strategies for completing missions, gaining high-level results. 相似文献
2.
T Seya M Nomura Y Murakami NA Begum M Matsumoto S Nagasawa 《Canadian Metallurgical Quarterly》1998,1(5):809-816
OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury. 相似文献
3.
There are several damping phenomena in quantum optics. Such phenomena have been usually explained by open systems. In statistical physics, open system dynamics have been used to study the irreversibility and the approach to equilibrium. In this paper, the dynamical change of the mutual entropy for an open system, frequently studied in the quantum optics literature, is rigorously computed through a model of quantum Markov chain. In particular, the concrete formula of Stinespring expression for such a model is obtained and applied to the derivation of the mutual entropy, and some computational results are presented. 相似文献
4.
Hideki Taguchi Yuzuru Takahashi Hiroki Miyamoto 《Journal of the American Ceramic Society》1985,68(10):264-C
Specimens of partially stabilized zirconia were slip cast from aqueous suspensions and sintered at 1500°C for 3 h. The relative density of the cast specimens and the firing shrinkage of the sintered specimens depend on the milling time for the suspension. Vickers hardness and KIC values of 11.46±s0.07 GN/m2 and 6.10 ±0.04 MN.m3/2 , respectively, were obtained for all sintered specimens. The dispersion of the suspension is important in increasing the relative density of the cast specimens. 相似文献
5.
To evaluate an association between Helicobacter pylori (H. pylori) infection and chronic atrophic gastritis (CAG), an established precursor of gastric cancer, we performed a cross-sectional study using IgG antibody against H. pylori and pepsinogens of blood donors in four prefectures in Japan. Although a geographic correlation between the age-adjusted prevalence rates for H. pylori infection and those for CAG was not seen, the age-adjusted odds ratios (OR) of H. pylori infection for CAG were high in each area (around five for men and from four to 12.6 for women). The association between them weakened with advancing age; the ORs in the youngest age group (16-29 yrs) and in the oldest age group (50-64 yrs) were 12.5 and 2.8 for men, and 11.5 and 5.2 for women, respectively. These findings suggest that H. pylori infection is strongly associated with CAG, while there are some other factors interacting in the development of CAG. A prospective cohort study in which CAG and H. pylori infection are taken into account will be necessary to assess the risks of gastric cancer. 相似文献
6.
Tetsuya Suemitsu Yoshino K. Fukai Hiroki Sugiyama Kazuo Watanabe Haruki Yokoyama 《Microelectronics Reliability》2002,42(1):47-52
The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (Rs) to increase at large drain bias voltages. The increase in Rs can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (Rd) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of Rs should be considered. It is also found that a deep gate recess suppresses the increase in Rd after long-term stressing. 相似文献
7.
In the drying of coated films with dispersed pigments, such as floppy disks, the structure of the film is formed during the drying process and depends on the drying condition. It is important to understand the structure formation during drying for the design of the dryer and die better quality of the product. We measured die drying characteristics of the film and determined the structure of dried film experimentally. A qualitative model for the structure formation during drying of the coated film is suggested. 相似文献
8.
H Nagasawa 《Canadian Metallurgical Quarterly》1993,106(2):295-300
1. The number of insect neuropeptides identified chemically grows rapidly and most important neuropeptides have already been characterized. After multi-year efforts Bombyx diapause hormone has recently been isolated and sequenced. 2. New approaches to search for new insect neuropeptides have been carried out by two groups of workers, which have succeeded in identifying several unique peptides. 3. cDNAs for more than 10 insect neuropeptides have been cloned and sequenced. It was found that two functionally distinct neuropeptides, Bombyx diapause hormone and pheromone biosynthesis activating neuropeptide, are encoded in a single gene. 相似文献
9.
10.
Complement activation generally does not occur on homologous cells. We observed C3 deposition on cultured human umbilical vein endothelial cells (HUVEC) when those which had died of apoptosis were treated with human serum. The C3 deposition on apoptotic HUVEC required Mg2+ but not Ca2+. In addition, the incubation of apoptotic HUVEC with purified C3, B, and D in the presence of Mg2+ resulted in C3 deposition. These results indicated that the C3 deposition on apoptotic HUVEC is mediated by the activation of the alternative complement pathway. C3 contains an intrachain thioester bond in the alpha chain (110 kDa) and upon activation to C3b, binds with membrane molecules by forming an ester or amide bond. Western blotting of reduced C3b-membrane molecule complexes, isolated from serum-treated apoptotic HUVEC by immunoprecipitation with anti-C3, revealed the covalent binding of C3b to several membrane molecules. Most of the C3b-membrane molecule complexes were cleaved by hydroxylamine, suggesting covalent binding via an ester bond. The molecular mass of the major alpha chain fragment released by hydroxylamine treatment was not 105 kDa but 68 kDa, which corresponds to the alpha 1 fragment of iC3b. These results indicate that most of the C3b on HUVEC was cleaved at its alpha' chain to yield iC3b, which consists of three disulfide-linked polypeptide chains and is a ligand of the complement receptor type 3 (CR3) of phagocytes. These results suggest that apoptotic HUVEC can activate the alternative pathway of the homologous complement and that the complement is related to the clearance of apoptotic cells by phagocytes. 相似文献