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101.
Social norms are cultural phenomena that naturally emerge in human societies and help to prescribe and proscribe normative patterns of behaviour. In recent times, the discipline of multi-agent systems has been used to model social norms in an artificial society of agents. In this paper we review norms in multi-agent systems and then explore a series of norms in a simulated urban traffic setting. Using game-theoretic concepts we define and offer an account of norm stability. Particularly in small groups, a relatively small number of individuals with cooperative attitude are needed for the norm of cooperation to evolve and be stable. In contrast, in larger populations, a larger proportion of cooperating individuals are required to achieve stability. 相似文献
102.
103.
This paper presents a technique to automatically detect third-layer cracks at rivet sites in aircraft structures using the response signals collected by giant magneto-resistive (GMR) sensors. The inspection system uses pulsed waveform as the excitation source of a multi-line coil and captures the transient fields associated with the induced eddy currents via a GMR sensor, which was developed to detect cracking and corrosion in multi-layer aircraft structures. An automatic scan of the region around the rivet generates C-scan image data that can be processed to detect cracks under the rivet head. Using a 2-D image of each rivet head, feature extraction and classification schemes based on principal component analysis and the k-means algorithm have been successfully developed to detect cracks of varying size located in the third layers at a depth of up to 10 mm below the surface. 相似文献
104.
Pritam Chakraborty N. Venkata Reddy 《Journal of Materials Processing Technology》2009,209(5):2464-2476
Minimization of surface area/volume of undercuts, flatness of parting surface and minimization of draw depth play a major role to determine the best pair of parting directions for two-piece permanent molds. In most of the earlier attempts a combined effect of the three factors was not considered. Moreover with the increasing complexity of molded product geometry, heuristic and feature-based approaches may prove inefficient. In this paper the combined affect of minimized surface area of undercut, flatness of parting surface and minimized draw depth is considered for the determination of best parting direction, parting line and surface for a two-piece permanent molded component. Tessellated geometry of the component is used as input. 相似文献
105.
106.
P. Pratapa Mowli N. Venkata Subbayya B. Sathyanarayana Rao 《The International journal of environmental studies》2013,70(3):159-163
Air quality monitoring has become a very important task. Conventional methods for monitoring particulate matter are tedious and require considerable effort and manpower. This paper provides the results of investigations in developing an inexpensive technique to monitor air pollution due to particulate matter. Three plants (i) Pedilanthus tithymaloides, (ii) Pedilanthus varigatum and (iii) Nephrolepis exaltata are selected for the study. From the investigations, it is found that the inexpensive technique is very useful in developiong and under developed countries. It is also established that certain types of plants are quite effective in arresting particulate matter. 相似文献
107.
Chandra Sekhar Espenti Kummari Subba Venkata Krishna Rao Palakurthi Ramesh Akila Chandra Sekhar Kummara Madhusudana Rao 《IET nanobiotechnology / IET》2020,14(6):485
In this examination, we researched the advantages of DNA fragmentation and metallic nanoparticles well‐appointed with biomolecules. A novel interpretation of DNA damage by Silver Nano‐Clusters (AgNCs) which were developed by the utilization of green synthesis method was demonstrated. The green synthesis of AgNCs was accomplished by utilizing the leaf extract of Salacia mulbarica (SM). The preparation of SM‐AgNCs was developed by estimating surface plasmon resonance peak around 449 nm by using a UV–Visible spectrophotometer. The effect of phytochemicals in SM leaf extract on the development of stable SM‐AgNCs was confirmed by FTIR spectroscopy. The size of the fabricated SM‐AgNCs was estimated by dynamic light scattering and zeta‐sizer analysis and the morphology of the SM‐AgNCs was examined by transmission electron microscopy. The presence of clusters of Ag particles in the prepared SM‐AgNCs was recognized by energy dispersion X‐ray analysis. The results show that saponins, phytosterols, and phenolic compounds present in plant extract may play a great part in developing the SM‐AgNCs in their specialized particles. The succeeded SM‐AgNCs shows incredible anti‐bacterial action towards Escherichia coli and Bacillus subtilis. In‐light of the antibacterial study, these SM‐AgNCs were analyzed with calf thymus‐DNA and found significant damage to the strand of thymus‐DNA.Inspec keywords: visible spectra, surface plasmon resonance, transmission electron microscopy, DNA, nanofabrication, particle size, X‐ray chemical analysis, ultraviolet spectra, molecular biophysics, nanomedicine, microorganisms, nanoparticles, silver, X‐ray diffraction, antibacterial activity, Fourier transform infrared spectra, biomedical materialsOther keywords: stable SM‐AgNCs, silver nanoparticles, ct‐DNA damage, metallic nanoparticles, silver nanoclusters, Salacia mulbarica leaf extract, reactive oxygen species, DNA fragmentation, surface plasmon resonance, UV‐Visible spectrophotometer, Fourier transform infrared spectroscopy, dynamic light scattering, Zeta‐sizer analysis, transmission electron microscopy, energy dispersive X‐ray analysis, saponins, phytosterols, phenolic compounds, plant extract, Escherichia coli, Bacillus subtilis, Ag 相似文献
108.
Biswanath Mahanty Kannan Pakshirajan Veeranki Venkata Dasu 《Polycyclic Aromatic Compounds》2013,33(1):56-73
A novel method for preparation of pyrene encapsulated alginate beads for controlled release delivery of pyrene is reported in this study. Five different bead types that varied on the organic phase for pyrene delivery, presence or absence of polyvinyl alcohol (PVA) and boric acid treatment were prepared. Based on the pyrene release profile, silicone oil encapsulated in PVA-alginate bead was selected where encapsulation efficiency was more than 99% without any solvent leakage. Silicone oil encapsulation was further confirmed in microscopy observations. Pyrene release behavior from the beads was explained by a diffusion controlled first order release (R2 > 0.96). Reusability of this bead was demonstrated, where pyrene was loaded from an external medium in a non-destructive way. Application of the system was finally established in a biodegradation study using Mycobacterium frederiksbergense, where simultaneous release and removal of pyrene along with appearance of pyrene metabolites was observed. 相似文献
109.
110.
Rice milling operation is a very energy-intensive process. The major qualities of the rice which are taken into consideration
while milling are the degree of milling and head rice yield. A laboratory abrasion polisher, modified by attaching a humidifying
and cooling unit, was used to polish long-grain Pusa Basmati rice in order to optimize the polishing conditions. Polishing experiments were carried out using central composite design
for a factorial with a central point, at different initial grain temperatures (5–25 °C) and milling chamber temperatures (11–25 °C)
at a constant humidity level of 95 ± 2% for different time intervals. Models capable of predicting the quality of milled rice
were developed using response surface methodology and used to determine optimum processing conditions. Responses such as degree
of milling (DOM), broken content, and specific energy consumption were used to assess product quality. Optimum milling conditions
of a minimum of 10% DOM, a broken content of 8%, and a specific energy consumption of 11 kJ/DOM were obtained at a milling
chamber temperature of 11 °C, an initial grain temperature of 15 °C, and a milling period of 180 s. 相似文献