DPN -- Dependability Priority Numbers

This paper proposes a novel model-based approach to combine the quantitative dependability (safety, reliability, availability, maintainability and IT security) analysis and trade-off analysis. The proposed approach is called DPN (Dependability Priority Numbers) and allows the comparison of different actual dependability characteristics of a systems with its target values and evaluates them regarding trade-off analysis criteria. Therefore, the target values of system dependability characteristics are taken as requirements, while the actual value of a specific system design are provided by quantitative and qualitative dependability analysis (FHA, FMEA, FMEDA, of CFT-based FTA). The DPN approach evaluates the fulfillment of individual target requirements and perform trade-offs between analysis objectives. We present the workflow and meta-model of the DPN approach, and illustrate our approach using a case study on a brake warning contact system. Hence, we demonstrate how the model-based DPNs improve system dependability by selecting the project crucial dependable design alternatives or measures

GoGlobal Rural-Urban

This is a book of edited articles and design projects from five years of collaborative international design projects in developed and developing economies, including China, Thailand, Ghana and Japan. Part One contains articles on initiatives including e-commerce models for developing economies, massclusivity and craft design. Part Two is dedicated to design solutions for China’s rural-urban migration issues, which affect 55 million people a year. The project enhances knowledge about the application of design thinking to national-level issues connecting policy to implementation, extending design activity into large-scale social and economic areas. The book follows an exhibition of design outcomes in London and Beijing (2010). Hall developed his chapter (‘Go Global: Ghana’) from a conference paper given at the ‘International Association of Societies of Design Research Conference’, South Korea (2009) and further expanded as a book chapter (with Barker) entitled ‘e-Artisans: Contemporary design for the global market’ in Global Design History (2011). ‘eArtisans’ researched a proposed e-commerce model linking designer-craftsmen with a global Internet sale and distribution model for African countries. The originality lay in proposing and testing knowledge, through design collaborations, in a combination of e-commerce enterprise models; it was significant in deploying the proposed model in an experimental educational initiative. The research was based on previous experience of design, craft and enterprise projects in Thailand and China, and aligned with a creative economies report by UNESCO (2008). The context was a collaboration at the KNUST, Kumasi, Ghana, where action-based research methods resulted in a case study illustrating cultural transfer. Support and partnership were also provided by Aid To Artisans, the British Council and Africa 53. A vital aspect was the discovery of how an e-commerce model changed design concepts and creative proposals. The GoGlobal project has continued with an edited publication, Designing Social City Experiences (Jin Nam and Hall 2013)

Spin-dependent Rotating Wigner Molecules in Quantum dots

The spin-dependent trial wave functions with rotational symmetry are introduced to describe rotating Wigner molecular states with spin degree of freedom in four- and five-electron quantum dots under magnetic fields. The functions are constructed with unrestricted Hartree-Fock orbits and projection technique in long-range interaction limit. They highly overlap with the exact-diagonalized ones and give the accurate energies in strong fields. The zero points, i.e. vortices of the functions have straightforward relations to the angular momenta of the states. The functions with different total spins automatically satisfy the angular momentum transition rules with the increase of magnetic fields and explicitly show magnetic couplings and characteristic oscillations with respect to the angular momenta. Based on the functions, it is demonstrated that the entanglement entropies of electrons depend on the z-component of total spin and rise with the increase of angular momenta

Diagenesis of Upper Cambrian Mount Simon Sandstone in the Illinois Basin - Microscale Investigation of Basinal Fluid Migration and Mass Transfer

A series of investigations were conducted to evaluate microscale evidence for basinal fluid migration in the Illinois basin during diagenesis of the Upper Cambrian Mount Simon Sandstone. Samples were examined using transmitted light and cathodoluminescence (CL) petrography, fluid inclusion analysis, and Secondary Ion Mass Spectrometry (SIMS) analysis of 18O/16O ratios and trace element compositions. Preliminary investigation of in situ laser ablation 40Ar-39Ar age dating techniques on authigenic K-feldspar over growths was also completed. Two major generations of quartz overgrowths are observed, on the basis of transmitted light and CL petrography and fluid inclusion studies. High-resolution (100 μm x 100 μm), gray-scale images of CL in authigenic quartz overgrowths were acquired using the electron microprobe. Generation 1 quartz overgrowths have low intensity, medium- to dark- gray CL and are associated with fluid inclusion homogenization temperatures (Th) of 60 - 95°C. Generation 2 quartz overgrowths have light-gray CL and are related to fluid inclusion Th of 100 - 145°C. Th decreases from the southern part of the basin towards the north. Burial temperatures estimated by stratigraphic reconstruction and thermal history modeling did not exceed 60 - 90°C, thus, passage of at least two generations of basinal fluid flow, at temperatures similar to or slightly elevated relative to burial temperature (Th = 60 - 145°C) through the Mount Simon Sandstone are indicated. Salinities of these Na-Ca-K-Mg-Cl-H2O fluids vary from 18 wt% to 25 wt% NaCl equivalent, suggesting that both diagenetic fluids were highly saline basinal brines. Ion-microprobe oxygen isotope analyses of authigenic K-feldspar and quartz reveal a south-to-north-increasing trend in δ18O values. Average K-feldspar δ18O (V-SMOW) values increase systematically from +14 ± 1‰ in the southernmost and deepest borehole samples from Illinois to +24 ± 2‰ in the northernmost outcrop samples in Wisconsin. A similar south-to-north trend was observed for quartz overgrowths (22 ± 2‰ to 28 ± 2‰). Within-sample δ18O variations of up to 9‰ are much greater than analytical precision of the ion probe. This may be, in part, the result of sampling different generations of cements, as supported by CL and fluid inclusion studies in quartz. CL zones within quartz overgrowths were analyzed to evaluate δ18O values in different generations of quartz cements. Generation 1 quartz cements have δ18O values that are equal to (within analytical precision) or greater than (up to 6.8‰ difference) generation 2 quartz cements. Overall, however, generation 1 cements are isotopically-enriched relative to generation 2 quartz cements. Constraints on fluid compositions using fluid-inclusion temperatures that were point-matched to δ18O values of quartz overgrowths containing these fluid inclusions reveal two distinct diagenetic fluids, corresponding to generation 1 (T \u3c 95°C) and generation 2 (T \u3e 95°C) fluids. the δ18O values of generation 1 fluid are about -5‰ in the southern portion of the basin and increase to ~ 0‰ in the northern part of the basin; δ18O values of generation 2 fluid increases from ~ +2‰ in the south to ~ +7‰ in the north. For the generation 1 diagenetic event (T \u3c 95°C), fluid temperatures are consistent with burial temperatures in the deeper part of the southern basin, where the fluid may have originated. Fluid temperatures in the northern part of the basin are lower than in the southern basin, but still higher than burial temperatures. Ion-microprobe studies of authigenic K-feldspar and quartz reveal that Rb, Sr, Ba, Pb, Fe, Mg, B, Ti, and Cl are present in trace amounts in authigenic K-feldspar. In quartz cements, K, Al, Fe, B, Ti, Mg, and Cl were detected. Strongly covariant relationships among Sr-Ba-Pb-Rb, Na-Mg-Ca-Cl, and K-Al in authigenic cements were attributed to their similar geochemical behaviors and incorporation modes, continuous chemical changes in the fluid during migration and cement precipitation, and the requirements of solid solution charge compensation. Concentrations of Ba, Sr, Rb, Pb, Fe, Ca, and Ce in diagenetic fluids were estimated on the basis of trace element contents in authigenic K-feldspar and distribution coefficients between sanidine and hydrothermal fluids. No correlation between fluid compositions and positions in the basin (south to north) is apparent. Total K+Na+Li+Mg+Ca concentrations are significantly higher in generation 2 quartz cement, compared to generation 1 cements; B and K are both notably enriched in generation 2. These differences suggest that later brines had a different composition. The lack of regional trends indicates more local control of the physiochemical environment on trace element concentrations in authigenic minerals, compared to their oxygen isotope of fluid inclusion compositions. Preliminary trials of in situ UV-laser probe 40Ar/39Ar dating of authigenic K-feldspar cements were largely unsuccessful in releasing Ar gas out of the overgrowths; rather, the UV-laser mostly shattered the grains, without melting them. Ar-laser step heating tests on areas ~ 50 x 50 μm in size released gas from both detrital and authigenic K-feldspar. An overwhelming amount of atmospheric air was also released from the ceramic adhesive, resulting in very large analytical errors related to air-compound corrections. Procedures need to be taken to reduce air in the ceramic adhesive during thin section preparation, if this ceramic is used to substitute for epoxies. This study demonstrates that in situ microscale ion probe analytical techniques have significant advantages over conventional analysis in obtaining oxygen isotope compositions and trace-element concentrations from very fine-grained authigenic minerals. High-resolution ion probe analysis, in concert with detailed CL petrography and fluid inclusion studies, may provide valuable geochemical constraints on low-temperature diagenesis and basinal fluid migration, revealing multiple events, regional flow directions, fluid compositions, and temperatures and possible fluid sources

CREDIT RISK PREFERENCE IN E-FINANCE: AN EMPIRICAL ANALYSIS OF P2P LENDING

Online P2P lending marketplaces match individual lenders and borrowers for unsecured loans via real-time auction without financial institutions as an intermediary. This paper aims to build up a theoretical framework from the perspectives of informational social influence and herding behavior to explain how individual investors’ participation of online financial community influence their credit risk preference in online P2P lending marketplaces under different financial situations. The research proposes that online financial community participants’ credit risk preference is higher than non-participants in investment decision making during non-financial crisis period, whereas online financial community participants’ credit risk preference is lower than non-participants during financial crisis period. This research plans to conduct a field study to test the proposed effect by examining individual investors’ real transaction data on Prosper.com during financial crisis period and non-financial crisis period as well as their membership records on the community of Prospers.org. An analytical model will be further estimated to test the proposition

Automatic seizure detection based on Machine Learning and EEG

The diagnosis and treatment of epilepsy depend on accurate seizure detection. In clinical practice, the evaluation of seizures is done by visual inspection of an electroencephalogram (EEG). it is very time­consuming and requires trained experts. Automatic seizure detection is important. Machine learning approaches are intensely being applied to this problem due to their ability to classify seizure conditions from a large amount of data, and provide pre­screened results for neurologists. This work proposes a variety of experiments with different machine­learning architectures (support vector machine SVM, K nearest neighbour KNN, random forest RF, feef forward neural network FFNN and convolutional neural network CNN) for the detection of epileptic seizures using multichannel EEG signals from the CHBT­MIT Scalp EEG Database. The best model built in this work contains a combination of a feed­forward neural network (FFNN) and a convolutional neural network (CNN). CNN input images are constructed by applying short­time Fourier transform (STFT) to electroencephalography (EEG) signals and then merged with statistical metrics into a FFNN. The best model of this project showed an outstanding performance of 98.615% accuracy, 98.737% sensitivity and 98.425% specificity. This work also includes a discussion of other exciting ideas that could lead to future research investigations

Ultrafast imaging of photoelectron packets generated from graphite surface

We present an electron projection imaging method to study the ultrafast evolution of photoelectron density distribution and transient fields near the surface. The dynamical profile of the photoelectrons from graphite reveals an origin of a thermionic emission, followed by an adiabatic process leading to electron acceleration and cooling before a freely expanding cloud is established. The hot electron emission is found to couple with a surface charge dipole layer formation, with a sheet density several orders of magnitude higher than that of the vacuum emitted cloud.Comment: 9 pages, 4 figures. Applied Physics Letter, in pres

General Form of Nonmonotone Line Search Techniques For Unconstrained Optimization

By using the forcing function, we proposed a general form of nonmonotone line search technique for unconstrained optimization. The technique includes some well known nonmonotone line search as special cases while independence on the nonmonotone parameter. We establish the global convergence of the method under weak conditions and we report the numerical test with a modified BFGS method to show the effectiveness of the proposed method

Efficient empirical-likelihood-based inferences for the single-index model

AbstractThis article proposes the efficient empirical-likelihood-based inferences for the single component of the parameter and the link function in the single-index model. Unlike the existing empirical likelihood procedures for the single-index model, the proposed profile empirical likelihood for the parameter is constructed by using some components of the maximum empirical likelihood estimator (MELE) based on a semiparametric efficient score. The empirical-likelihood-based inference for the link function is also considered. The resulting statistics are proved to follow a standard chi-squared limiting distribution. Simulation studies are undertaken to assess the finite sample performance of the proposed confidence intervals. An application to real data set is illustrated