Flexible Spectrum Management: Approaches for India

2015 ◽  
Vol 8 (1) ◽  
Author(s):  
Arturo Basaure ◽  
Heikki Kokkinen ◽  
Heikki Hämmäinen ◽  
V. Sridhar
Keyword(s):  
Large Scale ◽  
Mobile Services ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Management Approach ◽  
Unlicensed Spectrum ◽  
Spectrum Band ◽  
Management Policies ◽  
Management Approaches ◽  
Lock In

Radio spectrum for commercial mobile services continues to be scarce. Countries around the world have recognized the importance of efficient utilization of this scarce resource and have initiated regulatory and policy steps towards flexible approaches to spectrum management, including sharing of licensed spectrum, and releasing unlicensed spectrum for mobile services. Technologies for shared access and the associated standardization activities have also progressed towards possible large scale deployments. In this paper, we analyze the evolution of spectrum management policies using a causal model and indicate how the markets can lock in to either centralized or flexible approach. We also cite a use case of a flexible spectrum management approach using spectrum band fill option and indicate its suitability to the Indian context.

Basic Spectrum Sensing Techniques

2019 ◽  
pp. 70-84
Author(s):  
Bhuvaneswari P. T. V. ◽  
Bino J.
Keyword(s):  
Cognitive Radio ◽  
Spectrum Sensing ◽  
Spectrum Sharing ◽  
Cognitive Radio Network ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Radio Network ◽  
Spectrum Band ◽  
Radio Systems ◽  
Networking Technology

Cognitive radio network (CRN) is an upcoming networking technology that can utilize both radio spectrum and wireless resources efficiently based on the information gathered from the past experience. There are two types of users in CRN, namely primary and secondary. PUs (PU) have the license to operate in certain spectrum band while the secondary (SU) or cognitive radio (CR) users do not have the license to operate in the desired band. However, they can opportunistically utilize the unused frequency bands. Spectrum sensing, spectrum management, spectrum sharing, and spectrum mobility are the four major functions of cognitive radio systems. The main objective of spectrum sensing is to provide better spectrum access to CR users, without causing any harmful interference to PUs. Sensing accuracy is considered as the most important factor to determine the performance of cognitive radio network. In this chapter, the challenges and requirement involved in spectrum sensing are detailed. Further, various spectrum sensing basic techniques are also discussed in detail.

scholarly journals Reduced Foliar Disease and Increased Yield of Pumpkin Regardless of Management Approach or Fungicide Combinations

2007 ◽  
Vol 17 (1) ◽  
pp. 56-61 ◽  
Author(s):  
Kent E. Cushman ◽  
William B. Evans ◽  
David M. Ingram ◽  
Patrick D. Gerard ◽  
R. Allen Straw ◽  
...  
Keyword(s):  
Large Scale ◽  
Cucurbita Pepo ◽  
Southeastern United States ◽  
Management Approach ◽  
Preventative Treatment ◽  
High Input ◽  
Foliar Nitrogen ◽  
Foliar Diseases ◽  
Erysiphe Cichoracearum ◽  
Management Approaches

Small- and large-scale farmers must often decide when to begin application of fungicides, either before the onset of disease as a preventative treatment or after disease becomes evident in the field. Growers also must decide about products that claim to enhance fungicide efficacy when added to the spray mixture. A study was conducted during the summer of 2002 to investigate control of foliar diseases of vine crops (Cucurbita spp.) with low-input (LI) or high-input (HI) management approaches and six fungicide/spray combinations at four locations in southeastern United States. Fungicide applications began for LI when leaf disease first became evident and for HI about 20 days after seeding. Both approaches continued applications at 7- to 10-day intervals until harvest. Spray treatments consisted of a water-only control or one of six combinations of azoxystrobin/chlorothalonil alone or in combination with potassium bicarbonate, foliar phosphite (0N–12.2P–21.6K), or foliar nitrogen (25N–0P–0K). Azoxystrobin was applied in rotation with chlorothalonil for all treatments except the control. Seeds of ‘Lil’ Goblin’ pumpkin (Cucurbita pepo) were planted July to August and fruit harvested October to November, depending on location. Plants were rated twice for powdery mildew (Sphaerotheca fuliginea and Erysiphe cichoracearum) and downy mildew (Pseudoperonospora cubensis). HI did not significantly increase yield compared with LI. All fungicide treatments significantly increased yield and reduced foliar diseases compared with the water-only control. The simplest of treatments, the azoxystrobin/chlorothalonil rotation without any other chemicals, can be recommended for general use where strobilurin resistance has not been documented.

Relationships Between Instructional Quality and Classroom Management for Beginning Urban Teachers

2017 ◽  
Vol 46 (7) ◽  
pp. 355-365 ◽  
Author(s):  
Andrew Kwok
Keyword(s):  
Classroom Management ◽  
Student Behavior ◽  
Large Scale ◽  
Teacher Education Program ◽  
Instructional Quality ◽  
Management Approach ◽  
Urban Teachers ◽  
Urban Context ◽  
Teacher Authority ◽  
Management Approaches

This mixed-methods study explores the differences in 1st-year urban teachers’ classroom management beliefs and actions. The teachers in this study were in their first year of teaching in an urban context concurrent with their participation in a teacher education program offered at a large public university. Using program-wide surveys of 89 elementary and secondary teachers and qualitative data from five case participants, this study explores teachers’ behavioral, academic, and relational beliefs and how these beliefs shape the actions used in managing their classrooms. Specifically, the participants focused on both student behavior and academics when managing classrooms and did not singularly consider enforcing behavioral systems for obtaining teacher authority. Even with this focus, some of the participants were more relational in their classroom management approach and actively searched for ways to build relationships with students. More relational classroom managers were associated with higher ratings of instructional quality. These findings speak to the need for future large-scale studies on the use of relational classroom management approaches and how those approaches relate to instructional quality.

scholarly journals Radio Spectrum Management and RFI in the United States

1991 ◽  
Vol 112 ◽  
pp. 174-175
Author(s):  
R. Marcus Price
Keyword(s):  
United States ◽  
Department Of Defense ◽  
Government Regulation ◽  
The United States ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Federal Communications Commission ◽  
Private Companies ◽  
The Government ◽  
Government Body

ABSTRACTIn the United States, civil common carrier telecommunications are provided by private companies, not by any agency of the government. Regulation of these services and spectrum management oversight is provided by the Federal Communications Commission (FCC), an agency of the government. Government telecommunications are operated by individual agencies, e.g. the Department of Defense, under the overall regulation of the Office of Spectrum Management of the National Telecommunications and Information Administration (NTIA), a government body separate from the FCC. In bands shared by the civil and government sectors, liaison and coordination is effected between the FCC and the NTIA.

CSMC

2021 ◽  
Vol 5 (4) ◽  
pp. 1-22
Author(s):  
Hai Wang ◽  
Baoshen Guo ◽  
Shuai Wang ◽  
Tian He ◽  
Desheng Zhang
Keyword(s):  
Large Scale ◽  
Mobile Network ◽  
Signal Propagation ◽  
Spectrum Management ◽  
External Information ◽  
Temporal Uncertainty ◽  
Large Area ◽  
Fine Grained ◽  
Map Construction ◽  
Spatio Temporal

The rise concern about mobile communication performance has driven the growing demand for the construction of mobile network signal maps which are widely utilized in network monitoring, spectrum management, and indoor/outdoor localization. Existing studies such as time-consuming and labor-intensive site surveys are difficult to maintain an update-to-date finegrained signal map within a large area. The mobile crowdsensing (MCS) paradigm is a promising approach for building signal maps because collecting large-scale MCS data is low-cost and with little extra-efforts. However, the dynamic environment and the mobility of the crowd cause spatio-temporal uncertainty and sparsity of MCS. In this work, we leverage MCS as an opportunity to conduct the city-wide mobile network signal map construction. We propose a fine-grained city-wide Cellular Signal Map Construction (CSMC) framework to address two challenges including (i) the problem of missing and unreliable MCS data; (ii) spatio-temporal uncertainty of signal propagation. In particular, CSMC captures spatio-temporal characteristics of signals from both inter- and intra- cellular base stations and conducts missing signal recovery with Bayesian tensor decomposition to build large-area fine-grained signal maps. Furthermore, CSMC develops a context-aware multi-view fusion network to make full use of external information and enhance signal map construction accuracy. To evaluate the performance of CSMC, we conduct extensive experiments and ablation studies on a large-scale dataset with over 200GB MCS signal records collected from Shanghai. Experimental results demonstrate that our model outperforms state-of-the-art baselines in the accuracy of signal estimation and user localization.

Secure Intelligent Radio for Trains (SIRT)

2017 ◽  
Author(s):  
K. R. Damindra S. Bandara ◽  
Satish Kolli ◽  
Duminda Wijesekara
Keyword(s):  
Critical Infrastructure ◽  
Adaptive Modulation ◽  
Radio Spectrum ◽  
Spectrum Management ◽  
Worker Safety ◽  
Radio Noise ◽  
Radio Communication ◽  
Radio System ◽  
Cognitive Engine ◽  
Prototype Development

American Railroads are planning to complete implementing their Positive Train Control (PTC) systems by 2020. Safety objectives of PTC are to avoid inter-train collisions, train derailments and ensuring railroad worker safety. Under published specifications of I-ETMS (the PTC system developed by Class I freight railroads), the on-board PTC controller communicates with two networks; namely, the Signaling network and the Wayside Interface Unit network to gather navigational information such as the positions of other trains, the status of critical infrastructure (such as switches) and any hazardous conditions that may affect the train path. By design, PTC systems are predicated on having a reliable radio network operating in reserved radio spectrum, although the PTC system itself is designed to be a real-time fail safe distributed control systems. Secure Intelligent Radio for Trains (SIRT) is an intelligent radio that is customized to train operations with the aim of improving the reliability and security of the radio communication network. SIRT has two tiers. The upper tier has the Master Cognitive Engine (MCE) which communicates with other SIRT nodes to obtain signaling and wayside device information. To do so, the MCE communicates with cognitive engines at the lower tier of SIRT; namely the Cryptographic Cognitive Engine (CCE) (that provide cryptographic security and threat detection) and the Spectrum Management Cognitive Engine (SCE) (that uses spectrum monitoring, frequency hopping and adaptive modulation to ensure the reliability of the radio communication medium). We presented the architecture and the prototype development of the CCE in [1]. This paper presents the design of the MCE and the SCE. We are currently developing a prototype of the SCE and the MCE and testing the performance of our cognitive radio system under varying radio noise conditions. Our experiments show that SIRT dynamically switches modulation schemes in response to radio noise and switches channels in response to channel jamming.

scholarly journals Placenta accreta spectrum disorders—experience of management in a German tertiary perinatal centre

2020 ◽  
Author(s):  
Anja Bluth ◽  
Axel Schindelhauer ◽  
Katharina Nitzsche ◽  
Pauline Wimberger ◽  
Cahit Birdir
Keyword(s):  
Caesarean Section ◽  
Blood Loss ◽  
Placenta Accreta ◽  
Caesarean Section Rate ◽  
Management Strategies ◽  
Management Approach ◽  
Optimal Setting ◽  
Placenta Accreta Spectrum ◽  
Management Approaches

Abstract Purpose Placenta accreta spectrum (PAS) disorders can cause major intrapartum haemorrhage. The optimal management approach is not yet defined. We analysed available cases from a tertiary perinatal centre to compare the outcome of different individual management strategies. Methods A monocentric retrospective analysis was performed in patients with clinically confirmed diagnosis of PAS between 07/2012 and 12/2019. Electronic patient and ultrasound databases were examined for perinatal findings, peripartum morbidity including blood loss and management approaches such as (1) vaginal delivery and curettage, (2) caesarean section with placental removal versus left in situ and (3) planned, immediate or delayed hysterectomy. Results 46 cases were identified with an incidence of 2.49 per 1000 births. Median diagnosis of placenta accreta (56%), increta (39%) or percreta (4%) was made in 35 weeks of gestation. Prenatal detection rate was 33% for all cases and 78% for placenta increta. 33% showed an association with placenta praevia, 41% with previous caesarean section and 52% with previous curettage. Caesarean section rate was 65% and hysterectomy rate 39%. In 9% of the cases, the placenta primarily remained in situ. 54% of patients required blood transfusion. Blood loss did not differ between cases with versus without prenatal diagnosis (p = 0.327). In known cases, an attempt to remove the placenta did not show impact on blood loss (p = 0.417). Conclusion PAS should be managed in an optimal setting and with a well-coordinated team. Experience with different approaches should be proven in prospective multicentre studies to prepare recommendations for expected and unexpected need for management.

scholarly journals End-to-End Modeling Reveals Species-Specific Effects of Large-Scale Coastal Restoration on Living Resources Facing Climate Change

2021 ◽  
Vol 8 ◽  
Author(s):  
Kim de Mutsert ◽  
Kristy A. Lewis ◽  
Eric D. White ◽  
Joe Buszowski
Keyword(s):  
Climate Change ◽  
Risk Reduction ◽  
Large Scale ◽  
Ecosystem Model ◽  
Wetland Loss ◽  
Management Approach ◽  
Coastal Protection ◽  
Plan Implementation ◽  
Species Specific ◽  
Specific Species

Coastal erosion and wetland loss are affecting Louisiana to such an extent that the loss of land between 1932 and 2016 was close to 5,000 km2. To mitigate this decline, coastal protection and restoration projects are being planned and implemented by the State of Louisiana, United States. The Louisiana Coastal Master Plan (CMP) is an adaptive management approach that provides a suite of projects that are predicted to build or maintain land and protect coastal communities. Restoring the coast with this 50-year large-scale restoration and risk reduction plan has the potential to change the biomass and distribution of economically and ecologically important fisheries species in this region. However, not restoring the coast may have negative impacts on these species due to the loss of habitat. This research uses an ecosystem model to evaluate the effects of plan implementation versus a future without action (FWOA) on the biomass and distribution of fisheries species in the estuaries over 50 years of model simulations. By simulating effects using a spatially-explicit ecosystem model, not only can the changes in biomass in response to plan implementation be evaluated, but also the distribution of species in response to the planned restoration and risk reduction projects. Simulations are performed under two relative sea level rise (SLR) scenarios to understand the effects of climate change on project performance and subsequent fisheries species biomass and distribution. Simulation output of eight economically important fisheries species shows that the plan mostly results in increases in species biomass, but that the outcomes are species-specific and basin-specific. The SLR scenario highly affects the amount of wetland habitat maintained after 50 years (with higher levels of wetland loss under increased SLR) and, subsequently, the biomass of species depending on that habitat. Species distribution results can be used to identify expected changes for specific species on a regional basis. By making this type of information available to resource managers, precautionary measures of ecosystem management and adaptation can be implemented.

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