Hierarchical Spatial Reasoning theory and GIS technology applied to the automated delineation of administrative boundaries

Throughout history, humankind has segmented and delineated the geographic environment\ud in various ways to support administrative, political and economic activities. To date, the majority of spatial boundaries have been constructed in an uncoordinated manner with individual organisations generating individual boundaries to meet their own specific needs. As a result of this lack of coordination, there is a fragmentation of information over a series of boundary units, which not only limits the potential uses for data collected, but also the scope of analysis possible between boundary layers. The proposed solution outlined in this research involves the reorganisation of the spatial environment based on Hierarchical Spatial Reasoning (HSR) and the application of a GIS-based algorithm for the automated delineation of boundaries. By using this approach, it is expected that administrative boundaries can be formed through the aggregation of smaller units. This proposed system is focussed towards facilitating rapid and efficient cross analysis of data sets

Antioxidants, anticollagenase and antielastase potentials of ethanolic extract of ripe sesoot (Garcinia picrorrhiza Miq.) fruit as antiaging

Introduction: Nitric oxide (NO) is a free radical that belongs to reactive nitrogen species (RNS). The excess amount of NO in body generates physical changing on skin as a consequence of alteration in connective tissue through formation of lipid peroxides, cell content, and enzymes. These free radicals induce damage to extracellular matrix (ECM) and are responsible in reducing skin elasticity. Antioxidants possess significant role in delaying aging process by scavenging free radicals and preventing collagenase and elastase enzymes activities. This study aimed to evaluate antioxidants, anticollagenase and antielastase potentials of ethanolic extract of ripe sesoot (Garcinia picrorrhiza Miq.) fruit (GpKar) as antiaging remedy. Methods: Antioxidant activity was performed by NO scavenging activity assay, while anti-aging activity was performed through inhibitory effects of collagenase and elastase activities. Results: In antioxidant activity, GpKar had lower NO scavenging activity (IC50=1530.34 µg/ mL) compared to xanthone (IC50=85.40 µg/mL). In collagenase inhibitory activity, GpKar also had lower inhibition collagenase activity (IC50= 1169.31 µg/mL) compared to xanthone (IC50= 286.32 µg/mL). In elastase inhibitory activity, GpKar had lower inhibition elastase activity (IC50= 152.93 µg/mL) compared to xanthone (IC50= 21.26 µg/mL). Conclusion: In summary, GpKar and its compounds possess antioxidant, anticollagenase, and antielastase activities for antiaging, and might be beneficial in these subjects

PRACTICE

Past training as an athlete has driven me to reach for the unattainable goal of flawlessness. This mentality, which I apply to jewelry making, has led me to recreate the intricate angles of the athletic body and the beauty of its movements. I use gymnastics imagery within my work as a tool to communicate how we learn and understand through practice and repetition. With shifted lines, skewed shapes and geometric wirework, the jewelry tumbles over the architecture of the wearer’s body. The repetitive metal forms come together to simulate movement and enhance the physical language that a body in motion can suggests

Characterisation and statistical analysis of breakdown data for a corona-stabilised switch in environmentally-friendly gas mixtures

Characterisation of a corona-stabilised switch in the single-shot regime, including triggering range, delay times and jitter is reported, over the pressure range 0-3 bar gauge, as a continuation of work from similar characterisation with this switch filled with SF6 with different gap spacings. When filled with mixtures of HFO-1234ze and N2, the breakdown voltage can be increased by up to ~306% and ~191% under negative and positive polarity, respectively, of that using 100% N2. These results were achieved with gas mixtures consisting of 80% N2 and 20% HFO-1234ze, by pressure. The maximum negative polarity triggering range was 13.6 kV, comparable to that achieved previously using SF6. The measured delay time and calculated jitter was generally found to increase with increasing pressure, and with increasing percentage (from 5% to 20%) of HFO-1234ze in the gas mixtures. Von Laue statistical analysis of time-to-breakdown data showed that both the formative time and statistical time increased with increasing pressure, and with increasing percentage of HFO-1234ze in the gas mixtures. The formative time under negative polarity was significantly longer than that for positive polarity. The results indicate that HFO-1234ze may be considered as a suitable candidate to replace SF6 for switching applications, although there are some operational observations that require further investigation

Contingent Democrats in Action: Organized Labor and Regime Change in the Republic of Niger

The effects of organized labor on regime change in developing countries are not clear-cut. Optimists argue that union agitation is conducive to both democratic transition and consolidation processes. Pessimists hold that unions will support any regime that is conducive to their demands. Accordingly, unions may support regime transitions; however, once their economic interests are under threat, they will jeopardize the subsequent consolidation process. Systematic studies on the effects of organized labor on regime change in sub-Saharan Africa are sparse and largely confined to the (pre)transition phase. This article examines the role of organized labor in Niger between 1990 and 2010. Given the high number of regime breakdowns during the period, a longitudinal study of Nigerien labor enables a critical examination of motives and actions of organized labor toward different regime types. In contrast to other recent findings on African unionism, the article confirms the pessimistic view

Vacuum electrical breakdown characteristics and surface condition of Ti electrodes with oxidation conditions

http://ieeexplore.ieee.org/search/wrapper.jsp?arnumber=1593407 | http://ieeexplore.ieee.org/search/wrapper.jsp?arnumber=1593407Outgassing from an electrode surface is regarded as a major factor leading to electrical breakdowns in vacuum. Recently oxidation treatment at 200 degrees C was reported as an effective means of reducing Ti outgassing. In this paper, we report our measurement and comparison of the electrical breakdown characteristics of Ti electrodes with different oxidation conditions (without oxidation, oxidation at 200 degrees C, oxidation at 450 degrees C). In addition, we analyzed electrode surfaces before and after breakdown experiments in situ with X-ray photoelectron spectroscopy (XPS). Before oxidation, we machined the electrode's surfaces to the roughness of 0.8 mu m Rmax with diamond turning. Breakdown experiments demonstrated that the breakdown field is highest at the first application of voltage to electrodes with oxidized at 200 degrees C. Before breakdown experiment, surface analysis revealed that all the sample electrodes had a large amount of carbon originating from the hydrocarbons of contaminants, and after the experiments, they revealed that the carbons had disappeared. To obtain breakdown characteristics of electrodes with smoother surfaces, we conducted experiments on electrodes with a surface roughness of 0.05 mu m Ra. For these electrodes, the breakdown field was higher at first breakdown; the repetitions required to achieve saturated breakdown fields were significantly fewer, and the amount of carbon on electrode surfaces before breakdown was less.textapplication/pdfjournal articl

Transient spark discharges in high velocity airflow

Air-filled, self-breakdown plasma closing switches can operate at high pulse repetition frequency, when overstressed with HVDC voltage. However, their recovery characteristics, breakdown voltage, the achievable pulse repetition rate and variation in this rate are affected by the thermal effects local to the electrodes and by gas by-products generated by spark discharges. As a potential improvement to the performance of plasma closing switches, flowing gas can be forced through the inter-electrode gap. In this paper, it was shown that purging an inter-electrode gap of the plasma closing switch with air is a viable way of controlling the pulse repetition rate and variation of this rate. It was found that the difference between breakdown voltages of the first (single) breakdown events in static air and at 100 m/s air flow was less than 10%. In static air, the breakdown voltage of repetitive breakdown events decreases after the first and reaches its saturation value. It was shown that introduction of the air flow at 100 m/s leads to recovery of the repetitive breakdown voltage, which could reach its new saturation value, up to 30% higher than the first recorded breakdown voltage. Also, purging of the spark gap with air resulted in decreasing the pulse repetition rate, however it leads to higher breakdown voltage, lower variation in pulse repetition rate and increasing plasma conductivity in the spark channel, thereby increasing the efficiency of the overall high voltage system via reduced switching losses

Geometric dependence of radio-frequency breakdown in normal conducting accelerating structures

We present the experimental results of a systematic study of rf breakdown phenomenon in high vacuum accelerator structures. In this study, the surface processing, geometry, and materials of the structures have been varied, one parameter at a time. The breakdown rate or alternatively, the probability of breakdown/pulse/meter has been recorded for different operating parameters. These statistical data reveal a strong dependence of breakdown probability on surface magnetic field, or alternatively on surface pulsed heating. This is in contrast to the classical view of electric field dependence. We will present our experimental methodology and results showing this remarkable correlation

Effect of Carbon Nanotube Concentration on the Corrosion Behavior of Electroless Ni-B-CNT Coating

peer reviewedIn this study, Ni-B-CNT composite was deposited on AISI 4140 steel using different concentrations of CNTs ranging from 0.2 to 1 gr/lit in an electroless bath. The phase analysis and surface morphology of the samples were characterized using x-ray diffraction and FESEM. The corrosion behavior of the coated samples was investigated in a 3.5 wt.% NaCl solution through potentiodynamic polarization, EIS, and electrochemical noise (EN) analyses. The corroded surface of the samples was further analyzed via FESEM observation after 10 days of immersion in corrosive medium. It was found that although adding 0.2 gr/lit CNT in electroless solution improves corrosion resistance, increasing CNT concentration from 0.2 up to 1 gr/lit increases the corrosion rate. The FESEM observations and EN results imply that the formation of micro-galvanic cells in samples with high concentration of CNTs leads to nucleation and growth of the pits. The results revealed that no passive layer was formed on the surface of the Ni-B sample, and the corrosion occurred through ionic diffusion into the cracks and crevices. The results of potentiodynamic test show that adding CNTs into electroless bath facilitates the formation of passive layer. However, results of EN test imply that increasing CNT concentration causes repetitive breakdown and recovery of passive film