Approximately Efficient Online Mechanism Design

Online mechanism design (OMD) addresses the problem of sequential decision making in a stochastic environment with multiple self-interested agents. The goal in OMD is to make value-maximizing decisions despite this self-interest. In previous work we presented a Markov decision process (MDP)-based approach to OMD in large-scale problem domains. In practice the underlying MDP needed to solve OMD is too large and hence the mechanism must consider approximations. This raises the possibility that agents may be able to exploit the approximation for selfish gain. We adopt sparse-sampling-based MDP algorithms to implement efficient policies, and retain truth-revelation as an approximate Bayesian-Nash equilibrium. Our approach is empirically illustrated in the context of the dynamic allocation of WiFi connectivity to users in a coffeehouse.Engineering and Applied Science

Sustainable Availability Provision in Distributed Cloud Services

The article is an extension of this paper 1 . It describes methods for dealing with reliability and fault tolerance issues in cloud-based datacenters. These methods mainly focus on the elimination of a single point of failure within any component of the cloud infrastructure, availability of infrastructure and accessibility of cloud services. Methods for providing the availability of hardware, software and network components are also presented. The analysis of the actual accessibility of cloud services and the mapping of a cloud-based datacenter infrastructure with different levels of reliability to the Tier Classification System2 is described. Non-compliance of the actual accessibility with the level of High Availability for cloud web services is unraveled

In Situ Surface Characterization

Operation of in situ space assets, such as rovers and landers, requires operators to acquire a thorough understanding of the environment surrounding the spacecraft. The following programs help with that understanding by providing higher-level information characterizing the surface, which is not immediately obvious by just looking at the XYZ terrain data. This software suite covers three primary programs: marsuvw, marsrough, and marsslope, and two secondary programs, which together use XYZ data derived from in situ stereo imagery to characterize the surface by determining surface normal, surface roughness, and various aspects of local slope, respectively. These programs all use the Planetary Image Geometry (PIG) library to read mission-specific data files. The programs themselves are completely multimission; all mission dependencies are handled by PIG. The input data consists of images containing XYZ locations as derived by, e.g., marsxyz. The marsuvw program determines surface normals from XYZ data by gathering XYZ points from an area around each pixel and fitting a plane to those points. Outliers are rejected, and various consistency checks are applied. The result shows the orientation of the local surface at each point as a unit vector. The program can be run in two modes: standard, which is typically used for in situ arm work, and slope, which is typically used for rover mobility. The difference is primarily due to optimizations necessary for the larger patch sizes in the slope case. The marsrough program determines surface roughness in a small area around each pixel, which is defined as the maximum peak-to-peak deviation from the plane perpendicular to the surface normal at that pixel. The marsslope program takes a surface normal file as input and derives one of several slope-like outputs from it. The outputs include slope, slope rover direction (a measure of slope radially away from the rover), slope heading, slope magnitude, northerly tilt, and solar energy (compares the slope with the Sun s location at local noon). The marsuvwproj program projects a surface normal onto an arbitrary plane in space, resulting in a normalized 3D vector, which is constrained to lie in the plane. The marsuvwrot program rotates the vectors in a surface normal file, generating a new surface normal file. It also can change coordinate systems for an existing surface normal file. While the algorithms behind this suite are not particularly unique, what makes the programs useful is their integration into the larger in situ image processing system via the PIG library. They work directly with space in situ data, understanding the appropriate image metadata fields and updating them properly. The secondary programs (marsuvwproj, marsuvwrot) were originally developed to deal with anomalous situations on Opportunity and Spirit, respectively, but may have more general applicability

A Double Payload Complex between Hypericin and All-trans Retinoic Acid in the β-Lactoglobulin Protein

Combined therapies are usually used to treat acne vulgaris since this approach can tackle various foci simultaneously. Using a combination of spectroscopic, computational, and microbiological techniques and methods, herein we report on the use of β-lactoglobulin as a double payload carrier of hypericin (an antimicrobial photodynamic agent) and all-trans retinoic acid (an anti-inflammatory drug) for S. aureus in vitro photodynamic inactivation. The addition of all-trans retinoic acid to hypericinβ-lactoglobulin complex renders a photochemically safe vehicle due to the photophysical quenching of hypericin, which recovers its photodynamic activity when in contact with bacteria. The ability of hypericin to photoinactivate S. aureus was not affected by retinoic acid. β-Lactoglobulin is a novel biocompatible and photochemically safe nanovehicle with strong potential for the treatment of acne

SMART-ITEM: IoT-Enabled Smart Living

The main goal of this proposed project is to harness the emerging IoT technology to empower elderly population to self-manage their own health, stay active, healthy, and independent as long as possible within a smart and secured living environment. An integrated open-sourced IoT ecosystem will be developed. It will encompass the entire data lifecycle which involves the following processes: data acquisition, data transportation; data integration, processing, manipulation and computation; visualisation; data intelligence and exploitation; data sharing; data storage. This innovative cloud-based IoT ecosystem will provide a one-stop shop for integrated smart IoT-enabled services to support older people (greater or equal to 65 years old) who live alone at home (or care homes). Another innovation of this system is the design and implementation of an integrated IoT gateway for wellbeing wearable and home automation system sensors with varying communication protocols. The SMART-ITEM system and services will appropriately address the following (i) smart health and care; (ii) smart quality of life; (iii) SMART-ITEM social community. The development of the system will be based on the User Centred Design methodology so as to ensure active user engagement throughout the entire project lifecycle and necessary standards as well as compliances will be adhered to (e.g. security, trust and privacy) in order to enhance user acceptance

tert-Butyl 4-(1-methyl-1H-pyrazol-5-yl)piperidine-1-carboxyl­ate

The reaction of (E)-tert-butyl 4-[3-(dimethyl­amino)acrylo­yl]piperidine-1-carboxyl­ate with methyl­hydrazine leads to the formation of the title compound, C14H23N3O2, with a 1-methyl-1H-pyrazol-5-yl substituent. The plane of the pyrazole ring forms a dihedral angle of 33.4 (1)° with the approximate mirror plane of the piperidine ring

5-Chloro-N-[2-(1H-imidazol-4-yl)eth­yl]-N-methyl-7H-pyrrolo[2,3-d]pyrimidin-4-amine

The title compound, C12H13ClN6, was prepared by reaction of 4,5-dichloro-7H-pyrrolo[2,3-d]pyrimidine with 2-(1H-imid­azol-4-yl)-N-methyl­ethanamine, and the X-ray study confirmed that chloro-substituent in six-membered ring was replaced in the reaction. The exocyclic N atom environment is approximately coplanar with the pyrrolo[2,3-d]pyrimidine [corresponding dihedral angle is 5.5 (1)°], whereas the mean plane of the N—C—C—C link connecting with the imidazolyl ring is almost exactly orthogonal to the plane of the bicyclic system [dihedral angle = 91.6 (2)°]. The imidazolyl plane itself, however, forms a relatively small dihedral angle of 20.8 (1)° with the pyrrolo[2,3-d]pyrimidine plane. There are two independent N—H⋯N hydrogen bonds in the structure, which link mol­ecules into layers parallel to (03)

(R)-N-Methyl-4-[2-(methyl­sulfan­yl)pyrimidin-4-yl]-1-(tetra­hydro­furan-3-yl)-1H-pyrazol-5-amine

The chiral center at the substituted atom of the tetra­hydro­furanyl ring in the title compound, C13H17N5OS, has an R configuration. The methyl­sulfanylpyrimidine group and the pyrazole ring are almost coplanar [the maximum deviation from this plane is 0.070 (4) Å], the N—Me substituent being displaced from the methyl­sulfanylpyrimidine-pyrazole plane by 0.880 (4) Å. The secondary amine group participates in an intra­molecular hydrogen bond with the pyrimidine N atom in position 3

Photonuclear fission with quasimonoenergetic electron beams from laser wakefields

Recent advancements in laser wakefield accelerators have resulted in the generation of low divergence, hundred MeV, quasimonoenergetic electron beams. The bremsstrahlung produced by these highly energetic electrons in heavy converters includes a large number of MeV γγ rays that have been utilized to induce photofission in natural uranium. Analysis of the measured delayed γγ emission demonstrates production of greater than 3×1053×105 fission events per joule of laser energy, which is more than an order of magnitude greater than that previously achieved. Monte Carlo simulations model the generated bremsstrahlung spectrum and compare photofission yields as a function of target depth and incident electron energy.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/87815/2/231107_1.pd