• Title/Summary/Keyword: de-mapping

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Low-complexity de-mapping algorithms for 64-APSK signals

  • Bao, Junwei;Xu, Dazhuan;Zhang, Xiaofei;Luo, Hao
    • ETRI Journal
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    • v.41 no.3
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    • pp.308-315
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    • 2019
  • Due to its high spectrum efficiency, 64-amplitude phase-shift keying (64-APSK) is one of the primary technologies used in deep space communications and digital video broadcasting through satellite-second generation. However, 64-APSK suffers from considerable computational complexity because of the de-mapping method that it employs. In this study, a low-complexity de-mapping method for (4 + 12 + 20 + 28) 64-APSK is proposed in which we take full advantage of the symmetric characteristics of each symbol mapping. Moreover, we map the detected symbol to the first quadrant and then divide the region in this first quadrant into several partitions to simplify the formula. Theoretical analysis shows that the proposed method requires no operation of exponents and logarithms and involves only multiplication, addition, subtraction, and judgment. Simulation results validate that the time consumption is dramatically decreased with limited degradation of bit error rate performance.

Identification of the σ70-Dependent Promoter Controlling Expression of the ansPAB Operon of the Nitrogen-Fixing Bacterium Rhizobium etli

  • Angelica, Moreno-Enriquez;Zahaed, Evangelista-Martinez;Luis, Servin-Gonzalez;Maria Elena, Flores-Carrasco
    • Journal of Microbiology and Biotechnology
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    • v.25 no.8
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    • pp.1241-1245
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    • 2015
  • The aim of the present work was to examine the putative promoter region of the operon ansPAB and to determine the general elements required for the regulation of transcriptional activity. The transcriptional start site of the ansPAB promoter was determined by using highresolution S1-nuclease mapping. Sequence analysis of this region showed -10 and -35 elements, which were consistent with consensus sequences for R. etli promoters that are recognized by the major form of RNA polymerase containing the σ70 transcription factor. Mutation studies affecting several regions located upstream of the transcriptional start site confirmed the importance of these elements on transcriptional expression.

Augmented reality and dynamic infrared thermography for perforator mapping in the anterolateral thigh

  • Cifuentes, Ignacio Javier;Dagnino, Bruno Leonardo;Salisbury, Maria Carolina;Perez, Maria Eliana;Ortega, Claudia;Maldonado, Daniela
    • Archives of Plastic Surgery
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    • v.45 no.3
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    • pp.284-288
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    • 2018
  • Dynamic infrared thermography (DIRT) has been used for the preoperative mapping of cutaneous perforators. This technique has shown a positive correlation with intraoperative findings. Our aim was to evaluate the accuracy of perforator mapping with DIRT and augmented reality using a portable projector. For this purpose, three volunteers had both of their anterolateral thighs assessed for the presence and location of cutaneous perforators using DIRT. The obtained image of these "hotspots" was projected back onto the thigh and the presence of Doppler signals within a 10-cm diameter from the midpoint between the lateral patella and the anterior superior iliac spine was assessed using a handheld Doppler device. Hotspots were identified in all six anterolateral thighs and were successfully projected onto the skin. The median number of perforators identified within the area of interest was 5 (range, 3-8) and the median time needed to identify them was 3.5 minutes (range, 3.3-4.0 minutes). Every hotspot was correlated to a Doppler sound signal. In conclusion, augmented reality can be a reliable method for transferring the location of perforators identified by DIRT onto the thigh, facilitating its assessment and yielding a reliable map of potential perforators for flap raising.

Cost-Efficient Virtual Optical Network Embedding for Manageable Inter-Data-Center Connectivity

  • Perello, Jordi;Pavon-Marino, Pablo;Spadaro, Salvatore
    • ETRI Journal
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    • v.35 no.1
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    • pp.142-145
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    • 2013
  • Network virtualization opens the door to novel infrastructure services offering connectivity and node manageability. In this letter, we focus on the cost-efficient embedding of on-demand virtual optical network requests for interconnecting geographically distributed data centers. We present a mixed integer linear programming formulation that introduces flexibility in the virtual-physical node mapping to optimize the usage of the underlying physical resources. Illustrative results show that flexibility in the node mapping can reduce the number of add-drop ports required to serve the offered demands by 40%.

The use of HRSEM to characterize new and aged membranes in drinking water production

  • Wyart, Y.;Nitsche, S.;Chaudanson, D.;Glucina, K.;Moulin, P.
    • Membrane and Water Treatment
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    • v.2 no.4
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    • pp.251-266
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    • 2011
  • This work deals with the use of High Resolution Scanning Electron Microscopy (HRSEM) to verify ultrafiltration membrane selectivity at the end of the production line as well as membrane ageing. The first part of this work is focused on new membranes. It is shown that it is better to use sputtering metallization than vacuum deposition, as this latter technique entails thermal damage to the skin layer. Moreover, the impact of the metallization layer on the determination of the membrane pore size is studied and it is observed that no impact of the metallization step can be clearly defined for a metallization layer ranging from 3 to 12 nm. For example, an average pore size of 16.9 nm and a recovery rate of 6.5 % are observed for a 150 kDa cellulose acetate membrane. These results are in agreement with those given by the manufacturer: pore size ranging from 10 to 15 nm and recovery rate ranging from 5 to 10 %. The second part of this work focuses on the study of membrane ageing. A PVDF hollow fibre membrane is studied. It is shown that a 65 % decrease in the permeate flux can be linked to a decrease in the number of pores at the surface of the membrane and a decrease in the recovery rate. In conclusion, a mapping of the pores is performed for several new hollow fibre membranes used to produce drinking water, made of different materials, with different geometries and molecular weight cut-off. These results provide reference data that will help better understand the phenomena of membrane fouling and membrane ageing.

UNIFORMLY BOUNDED COMPOSITION OPERATORS ON A BANACH SPACE OF BOUNDED WIENER-YOUNG VARIATION FUNCTIONS

  • Glazowska, Dorota;Guerrero, Jose Atilio;Matkowski, Janusz;Merentes, Nelson
    • Bulletin of the Korean Mathematical Society
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    • v.50 no.2
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    • pp.675-685
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    • 2013
  • We prove, under some general assumptions, that a generator of any uniformly bounded Nemytskij operator, mapping a subset of space of functions of bounded variation in the sense of Wiener-Young into another space of this type, must be an affine function with respect to the second variable.

Spatial-temporal Assessment and Mapping of the Air Quality and Noise Pollution in a Sub-area Local Environment inside the Center of a Latin American Megacity: Universidad Nacional de Colombia - Bogotá Campus

  • Fredy Alejandro, Guevara Luna;Marco Andres, Guevara Luna;Nestor Yezid, Rojas Roa
    • Asian Journal of Atmospheric Environment
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    • v.12 no.3
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    • pp.232-243
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    • 2018
  • The construction, development and maintenance of an economically, environmentally and socially sustainable campus involves the integration of measuring tools and technical information that invites and encourages the community to know the actual state to generate positive actions for reducing the negative impacts over the local environment. At the Universidad Nacional de Colombia - Campus $Bogot{\acute{a}}$, a public area with daily traffic of more than 25000 people, the Environmental Management Bureau has committed with the monitoring of the noise pollution and air quality, as support to the campaigns aiming to reduce the pollutant emissions associated to the student's activities and campus operation. The target of this study is based in the implementation of mobile air quality and sonometry monitoring equipment, the mapping of the actual air quality and noise pollution inside the university campus as a novel methodology for a sub-area inside a megacity. This results and mapping are proposed as planning tool for the institution administrative sections. A mobile Kunak$^{(R)}$ Air & OPC air monitoring station with the capability to measure particulate matter $PM_{10}$, $PM_{2.5}$, Ozone ($O_3$), Sulfur Oxide ($SO_2$), Carbon Monoxide (CO) and Nitrogen Oxide ($NO_2$) as well as Temperature, Relative Humidity and Latitude and Longitude coordinates for the data georeferenciation; and a sonometer Cirrus$^{(R)}$ 162B Class 2 were used to perform the measurements. The measurements took place in conditions of academic activity and without it, with the aim of identify the impacts generated by the campus operation. Using the free code geographical information software QGIS$^{(R)}$ 2.18, the maps of each variable measured were developed, and the impacts generated by the operation of the campus were identified qualitative and quantitively. For the measured variables, an increase of around 21% for the $L_{Aeq}$ noise level and around 80% to 90% for air pollution were detected during the operation period.

Application of Opposition-based Differential Evolution Algorithm to Generation Expansion Planning Problem

  • Karthikeyan, K.;Kannan, S.;Baskar, S.;Thangaraj, C.
    • Journal of Electrical Engineering and Technology
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    • v.8 no.4
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    • pp.686-693
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    • 2013
  • Generation Expansion Planning (GEP) is one of the most important decision-making activities in electric utilities. Least-cost GEP is to determine the minimum-cost capacity addition plan (i.e., the type and number of candidate plants) that meets forecasted demand within a pre specified reliability criterion over a planning horizon. In this paper, Differential Evolution (DE), and Opposition-based Differential Evolution (ODE) algorithms have been applied to the GEP problem. The original GEP problem has been modified by incorporating Virtual Mapping Procedure (VMP). The GEP problem of a synthetic test systems for 6-year, 14-year and 24-year planning horizons having five types of candidate units have been considered. The results have been compared with Dynamic Programming (DP) method. The ODE performs well and converges faster than DE.

Direct Torque Control Strategy (DTC) Based on Fuzzy Logic Controller for a Permanent Magnet Synchronous Machine Drive

  • Tlemcani, A.;Bouchhida, O.;Benmansour, K.;Boudana, D.;Boucherit, M.S.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.1
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    • pp.66-78
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    • 2009
  • This paper introduces the design of a fuzzy logic controller in conjunction with direct torque control strategy for a Permanent Magnet synchronous machine. A stator flux angle mapping technique is proposed to reduce significantly the size of the rule base to a great extent so that the fuzzy reasoning speed increases. Also, a fuzzy resistance estimator is developed to estimate the change in the stator resistance. The change in the steady state value of stator current for a constant torque and flux reference is used to change the value of stator resistance used by the controller to match the machine resistance.