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1.
We estimated the tree structural variables (density, frequency and basal area) of true mangroves and soil variables like particle size distribution, carbon, available nitrogen and phosphorus, sulphur, nutrient cations (K, Na, Ca, Mg) of Cochin mangroves and examined the relationship between vegetation and environment. The study sites were classified as seaward fringe, riverine and interior. Of the thirteen true mangrove species present, Avicennia officinalis, Sonneratia caseolaris and Excoecaria agallocha showed higher Importance Value Index. The mean stem density varied from 80 to 25,000 no./ha and basal area from 0.1 to 39.68 m2/ha. Seaward mangroves showed maximum stand basal area and biomass production while riverine exhibited maximum density. Maturity Index value of Cochin mangroves revealed a very low degree of structural maturity. Interior mangroves were characterized by silty soil with higher nutrient concentrations. Principal component analysis of soil data revealed that the major factors influencing mangrove vegetation were soil texture, nutrients, salinity and oxidation–reduction potential. The stem density and basal area of different species correlated highly with soil nutrients and texture (p < .001) while salinity showed negative correlations with vegetation characteristics. The data generated in the study would be fundamental in site‐specific management and conservation efforts of these degrading mangroves.  相似文献   
2.
In this paper, we study the human oculomotor system as a simple mechanical control system. It is a well known physiological fact that all eye movements obey Listing's law, which states that eye orientations form a subset consisting of rotation matrices for which the axes are orthogonal to the normal gaze direction. First, we discuss the geometry of this restricted configuration space (referred to as the Listing space). Then we formulate the system as a simple mechanical control system with a holonomic constraint. We propose a realistic model with musculotendon complexes and address the question of controlling the gaze. As an example, an optimal energy control problem is formulated and numerically solved  相似文献   
3.
A novel series of sulfur-containing dihydrochromeno[8,7-e][1,3]oxazine-2(8H)-thiones has been synthesized through an eco-friendly Mannich-type condensation cyclization reaction of 7-hydroxy-4-methyl-2-thiocoumarin or 6-chloro-7-hydroxy-4-methyl-2-thiocoumarin with formaldehyde and primary amines in water at 80–90°C for 2 h. All the synthesized compounds were screened for their in vitro anti-bacterial efficacy against two Gram-positive and three Gram-negative bacterial strains by using the disc diffusion method. The compound (8c) was found to be most potent with the zone of inhibition of 16 and 15 mm against Staphylococcus aureus ATCC 2937 and Klebsiella pneumoniae ATCC 31488, respectively.  相似文献   
4.
5.
Some industry analysts believe that the impact of pen-based computers—also referred to as notepad or stylus computers and electronic slates—rivals that of desktop machines. This column describes how pen-based computers work and offers some suggestions for IS managers who want to implement pen-based computers into the current work environment.  相似文献   
6.
Electromotive force measurements of the cell:
have been made at 15, 25, 35 and 45°C for solvent compositions X = 10, 20, 30 and 40% (w/w) of dioxane. These have been used to evaluate the standard potentials of the cell and various thermodynamic functions for the transfer of (H+ SCN?) from water to the respective dioxane—water media. The standard free energy of transfer values along with those for halogen acids are briefly discussed in relation to ion solvation.  相似文献   
7.
A comprehensive study of the macrobenthic communities in the Kodungallur–Azhikode Estuary (KAE) was conducted during 2009–2011 period. A total of 18,846 organisms were collected, with 60% being malacostracans, followed by polychaetes (20%), molluscs (9%) and ‘others’ group (11%). A total of 79 species in 71 genera belonging to 49 families were identified, with 33 spp. being polychaetes, 26 spp. being malacostracans, 11 spp. being molluscs and 9 spp. being in the ‘others’ group. A single species of opportunistic amphipod (Americorophium triaeonyx) comprised more than 62.05% of the total numerical abundance of macrobenthos. The other dominant species were Obelia bidentata, Arcuatula senhousia, Cirolana fluviatilis, Prionospio cirrifera and Capitella sp. Canonical correspondence analysis (CCA) results indicated environmental parameters such as water column salinity, turbidity, sediment Eh, substratum type, chlorophyll‐a concentration, depth and organic matter in sediment were the significant factors influencing the distribution of macrobenthic species in the KAE. The present study provides baseline information for future KAE benthic studies.  相似文献   
8.
The texture and microstructure of Kradi cheese, an indigenous fresh unripened cheese of Jammu and Kashmir, India, were studied. There were significant differences (P < 0.05) for hardness, adhesiveness, springiness, cohesiveness, chewiness and resilience between samples from four different market areas. The optimised products made in the laboratory from cultures NCDC‐167 and NCDC‐144 showed significant differences (P < 0.05) in the textural and mechanical properties of tensile strength. The microstructure of the market samples was distinguished by the greater size of the voids present in three‐dimensional casein network. The optimised laboratory product had a more compact and fibrous structure compared to the market samples, which was attributed to its higher protein content.  相似文献   
9.
Airbags     
In recent years, safety systems such as seat belts and airbags have been one of the fast-growing sectors within the automotive industry. Seat belts and airbags have made driving substantially safer since their introduction. Airbags are safety systems used to cushion the driver or passenger during a collision and reduce bodily injuries. The technology involved in the manufacturing and working of airbags is complex. Since the early stages of development, airbag technology has been undergoing continual evolution in terms of design, materials and performance. Airbags are typically made from woven fabric, which may be coated or uncoated but must be impermeable to gases and flame resistant. In terms of their operation, modern airbags are smart restraint systems, which can tailor the deployment of the airbag according to the crash severity, body size of the occupant and proximity of the occupant to the airbag system prior to deployment. The future of airbags is extremely promising because there are many diverse applications ranging from motorcycle helmets to aircraft seating. In this article, an outline is given of the historical development of airbags and their value in saving lives is illustrated by supporting statistical data. The essential parameters required for airbag yarn and fabric components are discussed in detail. In addition, the processes involved in the manufacture, assembly and testing of airbag systems are explained. The mechanisms and chemical reactions involved in the deployment of different types of airbags are also discussed, and recent developments in airbag design and their possible future applications are reported.  相似文献   
10.
Hardware reconfigurability is an attractive solution for modern multi-standard wireless systems. This paper analyses the performance and implementation of an efficient triple-mode hexa-standard reconfigurable sigma-delta (∑?) modulator designed for six different wireless communication standards. Enhanced noise-shaping characteristics and increased digitisation rate, obtained by time-interleaved cross-coupling of ∑? paths, have been utilised for the modulator design. Power/hardware efficiency and the capability to acclimate the requirements of wide hexa-standard specifications are achieved by introducing an advanced noise-shaping structure, the dual-extended architecture. Simulation results of the proposed architecture using Hspice shows that the proposed modulator obtains a peak signal-to-noise ratio of 83.4/80.2/67.8/61.5/60.8/51.03 dB for hexa-standards, i.e. GSM????????/Bluetooth/GPS/WCDMA/WLAN/WiMAX standards with significantly less hardware and low operating frequency. The proposed architecture is implemented in 45 nm CMOS process using a 1 V supply and 0.7 V input range with a power consumption of 1.93 mW. Both architectural- and transistor-level simulation results prove the effectiveness and feasibility of this architecture to accomplish multi-standard cellular communication characteristics.  相似文献   
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