Emergent Properties of the Public Realm and Encroachments in the Urban Environment

The declining quality of the public realm in urban environment is a matter of concern and is found to be encroached upon in Indian cities. There is an urgent need to address this issue, and it is challenging for urban designers. Adopting an analytic framework addressing this ever-changing nature of the public realm in practice would be instrumental in improving the quality of urban life at large. The public realm in an urban environment is considered as a complex system to observe the macro-level behaviour—emergent properties which are either encouraging or discouraging for encroachments assumed to be the function of micro-level behaviour—elementary properties of interconnected and interdependent individual elements. Owing to the impossibility of experimenting with these emergent properties in the real world, an agent-based model—“Emergent Properties of Public Realm 3.1”—was developed in NetLogo 4.1.3. The typical cases representing the encroached and the un-encroached public realm were identified in the real world and experiments were conducted with varied interaction constants assumed to represent the pace of change in an urban environment. The output generated by the agent-based model was analyzed with respect to the real world.     

Unsteady development of a deformable bubble rising in a quiescent liquid

An accurate finite-volume based numerical method for the simulation of an isothermal two-phase flow, consisting of a rising deformable bubble translating in a quiescent, unbounded liquid, is presented. This direct simulation method is built on a sharp interface concept and developed on an Eulerian, Cartesian fixed-grid with a cut-cell scheme and marker points to track the moving interface. The unsteady Navier–Stokes equations in both liquid and gas phases are solved separately. The mass continuity and momentum flux conditions are explicitly matched at the true surface phase boundary to determine the evolving interface shape and movement of the bubble. The highlights of this method are that it utilizes a combined Eulerian–Lagrangian approach, and is capable of treating the interface as a sharp discontinuity. A fixed underlying grid is used to represent the control volume. The interface, however, is denoted by a separate set of marker particles which move along with the interface. A quadratic curve fitting algorithm with marker points is used to yield smooth and accurate information of the interface curvatures. This numerical scheme can handle a wide range of density and viscosity ratios. The bubble is assumed to be spherical and at rest initially, but deforms as it rises through the liquid pool due to buoyancy. Additionally, the flow is assumed to be axisymmetric and incompressible. The bubble deformation and dynamic motion are characterized by the Reynolds number, the Weber number, the density ratio and the viscosity ratio. The effects of these parameters on the translational bubble dynamics and shape are given and the physical mechanisms are explained and discussed. Results for the shape, velocity profile and various forces acting on the bubble are presented here as a function of time until the bubble reaches terminal velocity. The range of Reynolds numbers investigated is 1 < Re < 100, and that of Weber number is 1 < We < 10.     

Scanning electron microscopy of Streptomyces without use of any chemical fixatives

A new, short, and quick method was developed for preparation of specimen for observing Actinomycetes of genus Streptomyces by scanning electron microscopy. The cultures were directly grown on stubs and coated with a film of gold without using any fixative and dehydrating procedures. Using this simple preparation procedure, surface of intact sporing structures of Streptomyces was observed over a range of magnifications. As the preparation procedure is so simple and rapid, this procedure could be most useful for the routine examination and identification of Streptomyces.     

A new feature extraction and classification mechanisms For EEG signal processing

Multidimensional Systems and Signal Processing - The Electroencephalogram (EEG) signal processing is one of the extensively used research field in recent days, in which the epileptic seizure...     

Evaluating legacy assets in the context of migration to SOA

A key activity in the introduction of service oriented architecture (SOA) for an organization is to evaluate the suitability of existing assets for service orientation. We identify the core principles of SOA as the guide lines in evaluating the suitability of the existing assets. The existing metrics and guidelines that could be helpful in evaluating these principles are surveyed. This would benefit an organization in understanding the effort needed for migration and also to build proper services from the existing assets.

Methyl methacrylate–N-chlorophenyl maleimide copolymers: Effect of structure on properties

The article describes the preparation of cast acrylic sheets by copolymerizing methyl methacrylate (MMA) with varying mole fractions of N-o-chlorophenyl maleimide (OC), N-m-chlorophenyl maleimide (MC), and N-p-chlorophenyl maleimide (PC) using benzoyl peroxide as an initiator. The effect of incorporation of varying mole fraction of N-chlorophenyl maleimides in poly(methyl methacrylate) backbone on the optical, physicomechanical, and thermal properties of cast acrylic sheets were evaluated. Vicat softening temperature, glass transition temperature (T_g) and thermal stability of the copolymers increased with an increase in the maleimide content. The solar transmittance and percentage of transmittance of the copolymer sheets having low mole fractions of N-chlorophenyl maleimides (i.e., 0.025–0.085) were found to be comparable with that of PMMA. Further increase in the comonomer content resulted in a decrease in the percentage of transmittance. Copolymer sheets having low mole fractions of N-chlorophenyl maleimides (0.025–0.108) have tensile strength comparable to that of PMMA, whereas the percentage of elongation decreased. Tensile modulus increased with increasing mole fraction of N-chlorophenyl maleimides. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 527–534, 1998     

Are normal healthy research volunteers psychologically healthy? A pilot investigation.

Most new drug development in Phase I clinical trials relies on the use of "normal healthy research volunteers" (NHRVs); however, little is known about the personality functioning of these volunteers. Determining whether NHRVs are similar to or different from individuals with "normal" personalities can impact participant recruitment, group assignment, and statistical interpretation of study results. This pilot study was undertaken to gain insight into the demographics, personality functioning, and potential psychopathology of the volunteers who participated in a Phase I confinement clinical drug trial. NHRVs (N=28) in an all-male, Phase I clinical trial completed a battery of questions, including the Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and a sociodemographic questionnaire. Fifty percent of the sample showed clinically significant elevations on at least one of the scales. Current findings need to be replicated and expanded through future research. Results must be interpreted with caution because of the small, all-male sample. This preliminary study suggests that there is a difference in personality functioning between NHRVs and the general population. In addition, NHRVs may purposefully distort or conceal self-report information when participating in studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Controlling the Synaptic Plasticity of a Cu2S Gap‐Type Atomic Switch

It is demonstrated that a Cu₂S gap‐type atomic switch, referred to as a Cu₂S inorganic synapse, emulates the synaptic plasticity underlying the sensory, short‐term, and long‐term memory formations in the human brain. The change in conductance of the Cu₂S inorganic synapse is considered analogous to the change in strength of a biological synaptic connection known as the synaptic plasticity. The plasticity of the Cu₂S inorganic synapse is controlled depending on the interval, amplitude, and width of an input voltage pulse stimulation. Interestingly, the plasticity is influenced by the presence of air or moisture. Time‐dependent scanning tunneling microscopy images of the Cu‐protrusions grown in air and in vacuum provide clear evidence of the influence of air on their stability. Furthermore, the plasticity depends on temperature, such that a long‐term memory is achieved much faster at elevated temperatures with shorter or fewer number of input pulses, indicating a close analogy with a biological synapse where elevated temperature increases the degree of synaptic transmission. The ability to control the plasticity of the Cu₂S inorganic synapse justifies its potential as an advanced synthetic synapse with air/temperature sensibility for the development of artificial neural networks.     

Switching kinetics of a Cu2S-based gap-type atomic switch

The switching time of a Cu(2)S-based gap-type atomic switch is investigated as a function of temperature, bias voltage, and initial off-resistance. The gap-type atomic switch is realized using a scanning tunneling microscope (STM), in which the formation and annihilation of a Cu-atom bridge in the vacuum gap between the Cu(2)S electrode and the Pt tip of the STM are controlled by a solid-electrochemical reaction. Increasing the temperature decreases the switching time exponentially with an activation energy of about 1.38 eV. Increasing the bias voltage also shortens the switching time exponentially, exhibiting a greater exponent for the lower bias than for the higher bias. Furthermore, faster switching has been achieved by decreasing the initial off-resistance between the Cu(2)S electrode and STM tip. On the basis of these results, we suggest that, in addition to the chemical reaction, the electric field in the vacuum gap plays a significant role in the operation of a gap-type atomic switch. This investigation advances our understanding of the operating mechanism of an atomic switch, which is a new concept for future electronic devices.