scholarly journals Reducing the Cost of Implementing Filters in LoRa Devices

Sensors ◽  
2019 ◽  
Vol 19 (18) ◽  
pp. 4037
Author(s):  
Shania Stewart ◽  
Ha H. Nguyen ◽  
Robert Barton ◽  
Jerome Henry

This paper presents two methods to optimize LoRa (Low-Power Long-Range) devices so that implementing multiplier-less pulse shaping filters is more economical. Basic chirp waveforms can be generated more efficiently using the method of chirp segmentation so that only a quarter of the samples needs to be stored in the ROM. Quantization can also be applied to the basic chirp samples in order to reduce the number of unique input values to the filter, which in turn reduces the size of the lookup table for multiplier-less filter implementation. Various tests were performed on a simulated LoRa system in order to evaluate the impact of the quantization error on the system performance. By examining the occupied bandwidth, fast Fourier transform used for symbol demodulation, and bit-error rates, it is shown that even performing a high level of quantization does not cause significant performance degradation. Therefore, the memory requirements of LoRa devices can be significantly reduced by using the methods of chirp segmentation and quantization so as to improve the feasibility of implementing multiplier-less filters in LoRa devices.

2021 ◽  
Vol 15 (1) ◽  
pp. 152
Author(s):  
Lina Fuad Hussien

The purpose of this study is to analyze the asymmetry in cost behavior (cost stickiness) and to identify the impact of CEOs' compensation on the degree of cost stickiness behavior. The study population consists of the public shareholding companies listed on the ASE, which number (56) industrial company. Data were collected from (35) industrial companies for the period (2009 - 2019). To measure the degree of costs stickiness, The Model of Weiss (2010) was used. The Model of Weiss (2010) takes into account the costs and changes in the level of activity (sales) for the last four quarters of the company, Weiss (2010) model constructs the difference in logarithmic ratios of changes in cost. The study found that the CEO's compensation in Jordanian industrial companies consists of two forms. The companies pay fixed salaries or performance-related bonuses. The study found that the form of compensation that is paid to the CEO affects the behavior of managers. The results indicated that the performance-related rewards are accompanied by a decrease in the level of cost stickiness, and the compensation paid in the form of fixed salaries are accompanied by a high level of cost stickiness. The study recommends that companies should understand the role of the compensation form in administrative decisions, especially with regard to resource modifications, as management motives in relation to resource modifications must be taken into account because of their clear and direct impact on the cost structure of companies.


Author(s):  
Vibhu Grewal

RFID based applications used for many purposes like tagging and tracking for tag and reader in IoT deployment. This is because of its powerful features compared with similar techniques such as barcodes. In contrast, various attacks and security threats cause to RFID system. The aim of this paper is to use a heterogeneous ensemble of Fast Fourier Transform algorithm and Deoxyribonucleic acid (DNA) sequence operations. This is different from existing ECC work in the sense that we are proposing to combine state-of-the-art encryption methods by ensemble techniques instead of focusing on single technique. Our proposed protocol is highly secure and its strength is based on FFT and DNA encoding rules. When compared with ECC technique we validate and demonstrate our approach experimentally and it leads to significant performance gains.


2022 ◽  
Vol 18 ◽  
pp. 144-151
Author(s):  
Tetiana Kulinich ◽  
Nataliia Dobizha ◽  
Oksana Demchenko ◽  
Olena Bodnar ◽  
Viltoriia Myronchuk ◽  
...  

The main purpose of the academic paper is to analyze the dynamics of microfinance services and assess their impact on the entrepreneurial activity of small and medium-sized enterprises and the consequences for the population. Methods of generalization, analysis, comparison, correlation and regression analysis have been used in order to achieve the purpose outlined. The academic paper considers the impact of microfinance services on the performance of small and medium-sized enterprises in the form of net profit. The results have showed that the impact of the cost of microfinance services on the development of financial activities of small and medium-sized businesses have a positive result, and, when using the proposed regression equation, the company will receive positive results in 2020-2024. The conducted correlation analysis of the impact of microfinance services on the level of the average salary of the population of Ukraine has revealed a high level of dependence of citizens on loans obtained. This is confirmed by the high correlation coefficient.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Binh Van Nguyen ◽  
Hyoyoung Jung ◽  
Kiseon Kim

This paper investigates the antijamming performance of the NR-DCSK system. We consider practical jamming environments including broadband jamming (BBJ), partial-time jamming (PTJ), tone jamming (TJ), and sweep jamming (SWJ). We first analytically derived the bit error rates of the system under the BBJ and the PTJ. Our results show that the system performances under these two jamming environments are enhanced as P increases, where P is the parameter of the NR-DCSK modulation scheme denoting the number of times a chaotic sample is repeated. In addition, our results demonstrate that, for the PTJ, the optimal value of the jamming factor is close to zero when the jamming power is small; however, it increases and approaches one as the jamming power enlarges. We then investigate the performance of the system under the TJ and the SWJ via Monte-Carlo simulations. Our simulations show that single-tone jamming causes a more significant performance degradation than multitone jamming. Moreover, we point out that the system performance is significantly degraded when the starting frequency of the sweep jammer is close to the carrier frequency of the transmitted signals, the sweep bandwidth is small, and the sweep time is half of the transmitted bit duration.


2010 ◽  
Vol 5 (4) ◽  
pp. 481-508 ◽  
Author(s):  
Susan Gargett

AbstractIn response to predictions that population ageing will increase government spending over the coming decades, in 1997–98, the Australian Government introduced means-tested income fees and accommodation charges for those admitted to nursing homes with income and assets above set threshold levels. Immediately prior, all residents paid the same price for their care and were not required to contribute towards the cost of their accommodation. In addition, in relation to those eligible to pay a higher price, the Government reduced its subsidisation of the cost of their care. The Government anticipated that the initiative would more equitably share the cost of age-related services across the public and private sectors, and result in some cost savings for itself. The purpose of this study is to assess the impact of the policy on the average price paid by residents. The findings suggest that the policy may have contributed to an increase in the average price paid, but statistical evidence is limited due to a number of data issues. Results also indicate that the rate of increase in the price was greater after theResidential Aged Care Structural Reformpackage was introduced. The study contributes to the economic analysis of the sector by evaluating time series estimates of prices paid by residents since the early 1970s.


2020 ◽  
Author(s):  
Alexandre Becoulet ◽  
Amandine Verguet

The Split-Radix Fast Fourier Transform has the same low arithmetic complexity as the related Conjugate Pair Fast Fourier Transform. Both transforms have an irregular datapath structure which is straightforwardly expressed only in recursive forms. Furthermore, the conjugate pair variant has a complicated input indexing pattern which requires existing iterative implementations to rely on precomputed tables. It however allows optimization of the memory bandwidth as it requires a single twiddle factor load per radix-4 butterfly. In existing algorithms, this comes at the cost of using additional precomputed tables or performing recursive function calls. In this paper we present two novel approaches that handle both the butterfly scheduling and the input index generation of the Conjugate Pair Fast Fourier Transform. The proposed algorithm is cache-friendly because it is depth-first, non-recursive and does not rely on precomputed index tables. In order to achieve this, we relate the butterfly execution pattern of the Split-Radix and Conjugate Pair FFTs to the binary carry sequence. Based on this finding, we describe how common integer arithmetic and bitwise operations can be used to perform input reordering and depth-first traversal of the transform datapath with O(1) space complexity.<br>


2019 ◽  
Author(s):  
Eduardo A. Aponte ◽  
Dario Schöbi ◽  
Klaas E. Stephan ◽  
Jakob Heinzle

AbstractBackgroundPatients with schizophrenia make more errors than healthy subjects on the antisaccade task. In this paradigm, participants are required to inhibit a reflexive saccade to a target and to select the correct action (a saccade in the opposite direction). While the precise origin of this deficit is not clear, it has been connected to aberrant dopaminergic and cholinergic neuromodulation.MethodsTo study the impact of dopamine and acetylcholine on inhibitory control and action selection, we administered two selective drugs (levodopa 200mg/galantamine 8mg) to healthy volunteers (N=100) performing the antisaccade task. A computational model (SERIA) was employed to separate the contribution of inhibitory control and action selection to empirical reaction times and error rates.ResultsModeling suggested that levodopa improved action selection (at the cost of increased reaction times) but did not have a significant effect on inhibitory control. By contrast, according to our model, galantamine affected inhibitory control in a dose dependent fashion, reducing inhibition failures at low doses and increasing them at higher levels. These effects were sufficiently specific that the computational analysis allowed for identifying the drug administered to an individual with 70% accuracy.ConclusionsOur results do not support the hypothesis that elevated tonic dopamine strongly impairs inhibitory control. Rather levodopa improved the ability to select correct actions. Instead, inhibitory control was modulated by cholinergic drugs. This approach may provide a starting point for future computational assays that differentiate neuromodulatory abnormalities in heterogeneous diseases like schizophrenia.


Author(s):  
Chiara Santomauro ◽  
Penelope Sanderson

Field-based simulation research can be delayed or prevented due to restricted resources and other practical challenges. Although laboratory work is a feasible alternative, it is often criticized for a lack of generalizability. We faced this issue when investigating the impact of workplace interruptions on nurses’ work performance in the Intensive Care Unit (ICU). The potential relationship between interruptions and errors has been widely investigated in healthcare settings; however, much of the evidence is associative. Some evidence outside the healthcare domain points to a causal connection between interruptions and errors, but the studies are mostly laboratory based and interruptions are artificial to the situation. Our eventual aim is to carry out a high-fidelity randomized-controlled trial to test the hypothesis that interruptions cause errors in healthcare, which could have major implications for interventions and policy. However, there are considerable challenges and constraints to overcome when designing such an experiment; for example (a) a limited potential participant pool within the ICU, (b) constant changes to technology and procedures in the ICU, and (c) restricted access to hospital simulation rooms. There are various ways to address these issues but most options compromise the generalizability of the simulation to authentic situations. By adopting principles of Brunswick’s representative design, we designed an initial laboratory study to be used as a formal pilot study in a different, but parallel, context to healthcare. Representative design refers to the “arrangement of conditions of an experiment so that they represent the behavioural setting to which the results are intended to apply” (Araujo, Davids, & Passos, 2007, p. 72). Representing the ‘natural world’ with high fidelity is not crucial in representative design, but rather ensuring that the properties of the conditions to which the researcher wishes to generalize are adequately captured in the laboratory task (Hammond & Stewart, 2001). Accordingly, we have created a laboratory-based simulation on the basis of the properties we aim to capture in a healthcare-based simulation, so that we can generalize findings from the former to the latter. The laboratory component needed to involve a task that embodied the high-level properties of medication preparation and administration, with a specialized population who regularly perform the task. The task of cocktail making fits the above requirements because it has high-level properties similar to medication preparation and administration. Cocktail making is concerned with controlled liquids, it requires perceptual motor skills, it involves multi-step tasks carried out in a busy environment where there is a high demand on working memory, and it is performed by experts (bartenders). These similarities mean that cocktail making can be used as a laboratory analog of certain aspects of medication preparation and administration. First, we mapped the physical environment across the two domains to ensure the cocktail component possessed the same spatial properties as the medication component. Second, we designed the high-level structure of the cocktail scenarios to approximate the high-level structure of the medication component scenarios. Third, we designed the interrupting tasks and added them to the scenarios. Experiment 1 of the cocktail component was a condition with zero interruptions to provide a baseline error rate with which to calculate the required sample size for Experiment 2. Experiment 2 was a between-subjects study in which participants were randomly assigned to receive either 3 or 12 interruptions. All participants had at least one-month cocktail making experience in a licensed venue. Cocktail errors were the analog of clinical errors in healthcare (Westbrook et al., 2010). In Experiment 1, an average of 44% of cocktails made contained at least one error per scenario ( SD = 18%). To calculate the required sample size for Experiment 2, an effect size was calculated by integrating our baseline data with observational data from Westbrook et al. (2010) and a power analysis was performed. Data collection for Experiment 2 is now completed. The findings from Experiment 2 will be used to calculate the required sample size for the medication component and lessons learned from the cocktail component will help finalize the design of the medication component. The cocktail component of our study is not totally analogous to the medication component, but we have shown that principles of representative design can be used to design a simulation from which we can argue that generalizable findings can be gathered. A major advantage of our approach is that we have been able to design and test many formal aspects of the medication component of our study prior to stepping into the hospital simulator. Findings from the medication component will help to shape interventions and policies in the healthcare domain that reduce error rates and increase patient safety. The cocktail component will contribute to the interruptions literature because the interruptions are representative of those that would actually occur in the workplace – something that is rare in laboratory-based interruptions research.


2020 ◽  
pp. 112972982098428
Author(s):  
Mª Inés Corcuera Martínez ◽  
Marco Aldonza Torres ◽  
Ana Mª Díez Revilla ◽  
Sara Maali Centeno ◽  
Amaya Mañeru Oria ◽  
...  

Background: A vascular access team (VAT) was created in 2018 with the aim of improving vascular access and reducing complications associated with catheters. The impact of the introduction of a VAT in the insertion and maintenance of peripheral insertion central catheters (PICCs) was assessed. The cost-benefit associated with the use of a VAT was evaluated and the satisfaction of patients and professionals interacting with the VAT was measured. Methods: In a prospective study, 275 PICCs inserted by the VAT were assessed for their impact on complications. PICCs were implanted with maximum barrier measures using an ultrasound with IC-ECG. Also, patient and professional satisfaction have been analysed thought a questionnaire over the phone or online, and hospital financial data was used to assess the cost impact of the insertion methodology followed by the VAT versus Anaesthesia Service. Results: The thrombosis rate was 2.5% (7) and the bacteraemia rate was 1.1% (3). The use of the IC-ECG was correlated with a lower complication than the RX + IC-ECG (OR = 3.28, p = 0.021). In addition, there was a high level of perceived satisfaction for the patients surveyed and for the healthcare professionals involved in the care and management of these devices. The calculated saving for the implementation of the VAT was 61.81% compared with PICCs implanted in Anaesthesia Service. Conclusion: Low complication rates and high overall satisfaction scores in patients and professionals were observed, showing that a specialist VAT can have a positive impact in the insertion of PICCs and which also has a clear economic benefit.


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