A successive refinement approach to wireless infrastructure network deployment

Wireless security is the prevention of unauthorized access to computers using wireless networks .The trends in wireless networks over the last few years is same as growth of internet. Wireless networks have reduced the human intervention for accessing data at various sites .It is achieved by replacing wired infrastructure with wireless infrastructure. Some of the key challenges in wireless networks are Signal weakening, movement, increase data rate, minimizing size and cost, security of user and QoS (Quality of service) parameters... The goal of this paper is to minimize challenges that are in way of our understanding of wireless network and wireless network performance.

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The Influence of Increased Salvage Felling on Forwarding Distance and the Removal—A Case Study from Croatia

Forests ◽

10.3390/f12010007 ◽

2020 ◽

Vol 12 (1) ◽

pp. 7

Author(s):

Andreja Đuka ◽

Zoran Bumber ◽

Tomislav Poršinsky ◽

Ivica Papa ◽

Tibor Pentek

Keyword(s):

Spatial Distribution ◽

Management Plan ◽

Management Unit ◽

Negative Effects ◽

Forest Operations ◽

Spatial Reference ◽

Infrastructure Network ◽

Gis Environment ◽

Research Period

During the seven-year research period, the average annual removal was by 3274 m3 higher than the average annual removal prescribed by the existing management plan (MP). The main reason lies in the high amount of salvage felling volume at 55,238 m3 (38.3%) in both the main and the intermediate felling due to oak dieback. The analysis of forest accessibility took into account the spatial distribution of cutblocks (with ongoing felling operations) and the volume of felled timber for two proposed factors: (1) the position of the cutblock and (2) the position of the removal. Cutblock position factor took into account the spatial position of the felling areas/sites, while removal position factor besides the spatial reference took into account the amount of felled timber (i.e., volume) both concerning forest infrastructure network and forest operations. The analysed relative forest openness by using geo-processing workflows in GIS environment showed four types of opening areas in the studied management unit (MU): single-opened, multiple-opened, unopened and opened areas outside of the management unit. Negative effects of the piece-volume law and low harvesting densities on forest operations are highlighted in this research due to high amount of salvage felling particularly in the intermediate felling by replacing timber volume that should have come from thinnings.

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EXPRESS: Exploration of Principal Component Analysis: Deriving PCA Visually Using Spectra

Applied Spectroscopy ◽

10.1177/0003702820987847 ◽

2021 ◽

pp. 000370282098784

Author(s):

James Renwick Beattie ◽

Francis Esmonde-White

Keyword(s):

Principal Components ◽

Principal Component ◽

Original Data ◽

Specific Chemical ◽

Successive Refinement ◽

Minimal Loss ◽

Components Analysis ◽

The Mathematical Model ◽

Application Specific ◽

Reconstructed Data

Spectroscopy rapidly captures a large amount of data that is not directly interpretable. Principal Components Analysis (PCA) is widely used to simplify complex spectral datasets into comprehensible information by identifying recurring patterns in the data with minimal loss of information. The linear algebra underpinning PCA is not well understood by many applied analytical scientists and spectroscopists who use PCA. The meaning of features identified through PCA are often unclear. This manuscript traces the journey of the spectra themselves through the operations behind PCA, with each step illustrated by simulated spectra. PCA relies solely on the information within the spectra, consequently the mathematical model is dependent on the nature of the data itself. The direct links between model and spectra allow concrete spectroscopic explanation of PCA, such the scores representing âconcentrationâ or âweightsâ. The principal components (loadings) are by definition hidden, repeated and uncorrelated spectral shapes that linearly combine to generate the observed spectra. They can be visualized as subtraction spectra between extreme differences within the dataset. Each PC is shown to be a successive refinement of the estimated spectra, improving the fit between PC reconstructed data and the original data. Understanding the data-led development of a PCA model shows how to interpret application specific chemical meaning of the PCA loadings and how to analyze scores. A critical benefit of PCA is its simplicity and the succinctness of its description of a dataset, making it powerful and flexible.

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A rendezvous reservation protocol for energy constrained wireless infrastructure networks

Wireless Networks ◽

10.1007/s11276-006-0799-2 ◽

2006 ◽

Vol 13 (1) ◽

pp. 93-105 ◽

Cited By ~ 2

Author(s):

Subalakshmi Venugopal ◽

Wesley Chen ◽

T. D. Todd ◽

Krishna Sivalingam

Keyword(s):

Infrastructure Networks ◽

Reservation Protocol ◽

Energy Constrained ◽

Wireless Infrastructure

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Automatic spatial metadata systems – the case of Australian urban research infrastructure network

Cartography and Geographic Information Science ◽

10.1080/15230406.2016.1154805 ◽

2016 ◽

Vol 44 (4) ◽

pp. 327-337 ◽

Cited By ~ 3

Author(s):

Mohsen Kalantari ◽

Abbas Rajabifard ◽

Hamed Olfat ◽

Chris Pettit ◽

Azadeh Keshtiarast

Keyword(s):

Research Infrastructure ◽

Urban Research ◽

Infrastructure Network

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The Measurement of Logistics Industry Efficiency Based on the Construction of Tobacco Transport Logistics Infrastructure

Tobacco Regulatory Science ◽

10.18001/trs.7.5.1.51 ◽

2021 ◽

Vol 7 (5) ◽

pp. 2827-2847

Author(s):

Li Jian ◽

Zhang Lu

Keyword(s):

Market Competition ◽

Malmquist Index ◽

Developed Countries ◽

Service Level ◽

Logistics Industry ◽

Index Model ◽

Significant Difference ◽

Infrastructure Network ◽

Low Efficiency ◽

Logistics Performance Index

With the increasingly fierce market competition, China’s tobacco industry has been severely tested. At the same time, according to the latest report of global Logistics Performance Index (LPI), there is a significant difference between China’s LPI and other developed countries, indicating that China’s logistics has low efficiency, high input and low output. How to improve the service level and operation efficiency of tobacco enterprises by strengthening the construction of logistics infrastructure network is an urgent problem for tobacco enterprises to solve. Therefore, DEA model and Malmquist index model are adopted in this paper to measure the logistics efficiency of Chinese tobacco enterprises from the aspect of logistics infrastructure network construction. This paper analyzes the state of logistics efficiency and the reasons of low efficiency in some economic regions and puts forward countermeasures and suggestions to improve the logistics efficiency of tobacco enterprises based on the construction of logistics infrastructure network.

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