9,708 research outputs found
Possible Way to Synthesize Superheavy Element Z=117
Within the framework of the dinuclear system model, the production of
superheavy element Z=117 in possible projectile-target combinations is analyzed
systematically. The calculated results show that the production cross sections
are strongly dependent on the reaction systems. Optimal combinations,
corresponding excitation energies and evaporation channels are proposed in this
letter, such as the isotopes ^{248,249}Bk in ^{48}Ca induced reactions in 3n
evaporation channels and the reactions ^{45}Sc+^{246,248}Cm in 3n and 4n
channels, and the system ^{51}V+^{244}Pu in 3n channel.Comment: 10 pages, 4 figures, 1 tabl
Learning skills : robotics technology in automotive powertrain assembly
The past 40 years have seen industrial robots establish their superiority over humans in most areas of manufacturing requiring endurance or repeatability. One important application domain, however, has so far lagged behind the industry’s expectations: mechanical assembly. As fast, precise and dependable as they are, traditional industrial robots just don’t seem able to perform certain assembly operations as well as a skilled human worker. A task as simple as screwing a light bulb into a lamp socket shows why. Applying the right amount of force and turning the bulb at just the right time, at exactly the right angle, is something a human does intuitively. How can a robot be programmed to do this? For robots to successfully emulate humans on an assembly line, they need to have force-sensing capability and exhibit compliance. They must be able to direct forces and moments in a controlled way, and react to contact information. New robot force control technology from ABB shows how
Gossamer Superconductivity near Antiferromagnetic Mott Insulator in Layered Organic Conductors
Layered organic superconductors are on the verge of the Mott insulator. We
use Gutzwiller variational method to study a Hubbard model including a spin
exchange coupling term. The ground state is found to be a Gossamer
superconductor at small on-site Coulomb repulsion U and an antiferromagnetic
Mott insulator at large U, separated by a first order phase transition. Our
theory is qualitatively consistent with major experiments reported in organic
superconductors.Comment: 5 pages, 3 figure
Towards run-time monitoring of web services conformance to business-level agreements
Web service behaviour is currently specified in a mixture of ways, often using methods that are only partially complete. These range from static functional specifications, based on interfaces in WSDL and preconditions in RIF, to business process simulations using executable process-based models such as BPEL, to detailed quality of service (QoS) agreements laid down in a service level agreement (SLA). This paper recognises that something similar to a SLA is required at the higher business level to govern the contract between service producers, brokers and consumers. We call this a business level agreement (BLA) and within this framework, seek to unify disparate aspects of functional specification, QoS and run-time verification. We propose that the method for validating a web service with respect to its advertised BLA should be based on run-time service monitoring. This is a position paper towards defining these goals
Recommended from our members
Shock wave boundary layer interaction controlled by surface arc plasma actuators
An array of 16 surface arc plasma actuators (SAPAs) is employed to control the shock wave boundary layer interaction (SWBLI) at a 26° compression ramp in a Mach 2.0 flow. A new electrical circuit is used to actuate all 16 SAPAs. The electrical measurement reveals significant augmentation in peak current (200 A) and an energy deposition of 1.05 J, which are the nominal characteristics of the setup. The SAPA array is later applied for SWBLI control. The actuator array is placed upstream of the SWBLI and operates at four different frequencies, namely, 500 Hz, 1 kHz, 2 kHz, and 5 kHz. In the wind tunnel experiment, high-speed schlieren at 25 000 frames per second is used for flow visualization. The shock wave system is modified significantly by the controlling gas blobs (CGBs) or controlling gas bulbs (CGBUs) generated by SAPAs. The foot portion of the separation shock wave disappears, and the oblique shock wave bifurcates when the CGBs pass through the interaction region. The shock weakening effect is further verified through the rms of the schlieren intensity of the same phase
Study on the electronic structures of the reduced anatase TiO2 by the first-principle calculation
Employing the first-principle calculations based on the density functional theory (DFT) and the Molecule Orbital theory (MO), we have researched the electronic structures of the reduced anatase TiO2 and its visible light photoactivity. The study is emphasized on the O vacancy, including the components of the defect states, the relationship with the bulk states and the way in which these electrons occupying the defect states are distributed in the real space. We find that the origin of the visible light photoactivity should be due to the transition of the excited electrons from the defect states sigma subscript g orbital to the sigma subscript u orbital in the upper conduction bands, rather than arising from the reduction of the band gap. The calculated results indicate that the localized defect states induced by the neutral and doubly ionized oxygen vacancies are all located in the band gap
Electro-spraying and catalytic combustion characteristics of ethanol in meso-scale combustors with steel and platinum meshes
© 2018 Elsevier Ltd An experimental study on electro-spraying and catalytic combustion of ethanol at meso-scale is carried out. The electro-spraying process of ethanol is visualized and four typical spraying modes are identified. Based on droplet size measurements by a Phase Doppler Anemometer, the spraying at the cone-jet or multi-jet mode is suitable for meso-scale combustion. Two meso-combustors without and with the platinum catalyst, denoted as combustor A and combustor B, respectively, are designed to conduct the comparative experiments. The flame temperature at the cone-jet mode is higher than those at other modes when equivalence ratio φ = 1.0, and for the combustor with catalyst, fuel-lean conditions are favorable for stable combustion. It is also found that the carbon monoxide mole fraction in the exhaust decreases by at least 25% due to the catalytic effect. At the cone-jet electro-spraying mode, the combustion efficiencies of ethanol reach the highest value for both combustor A and combustor B due to smaller droplet size and more uniform droplet size distribution. Under the same conditions, combustion efficiency of ethanol can be improved by 4.5% for combustor B, which proves that the platinum catalyst can accelerate the decomposition of ethanol
Depression Involved in the Chemotherapy Induced Event-based Prospective Memory Impairment in Breast Cancer Survivors
The aim of this study was to investigate the relationships between depression and occurrence of chemotherapy induced prospective memory impairment in patients with breast cancer (BC).The 63 BC patients before and after chemotherapy were administered with the self-rating depression scale (SDS) and a battery of cognitive neuropsychological tests including event-based and time-based prospective memory (EBPM and TBPM, respectively) tasks. The changes in their prospective memory and cognitive neuropsychological characteristics before and after chemotherapy were compared. Compared with the scores before chemotherapy, the EBPM score exhibited a statistically significant difference after chemotherapy (t = 6.069, P 0.05). Further, compared with the patients without depression, the patients with depression exhibited a statistically significant difference in the EBPM score (t = -4.348, P 0.05). Post-chemotherapy, EBPM and overall cognitive functions in BC patients merged with depression were found to decline, while TBPM did not show a significant change, suggesting that the combination of chemotherapy and depression might be related with the occurrence of post-chemotherapy EBPM impairment
- …