Machine Learning and Soil Humidity Sensing: Signal Strength Approach

The Internet-of-Things vision of ubiquitous and pervasive computing gives rise to future smart irrigation systems comprising the physical and digital worlds. A smart irrigation ecosystem combined with Machine Learning can provide solutions that successfully solve the soil humidity sensing task in order to ensure optimal water usage. Existing solutions are based on data received from the power hungry/expensive sensors that are transmitting the sensed data over the wireless channel. Over time, the systems become difficult to maintain, especially in remote areas due to the battery replacement issues with a large number of devices. Therefore, a novel solution must provide an alternative, cost- and energy-effective device that has unique advantage over the existing solutions. This work explores the concept of a novel, low-power, LoRa-based, cost-effective system that achieves humidity sensing using Deep Learning techniques that can be employed to sense soil humidity with high accuracy simply by measuring the signal strength of the given underground beacon device.

Accurate indoor positioning system based on modify nearest point technique

Wireless fidelity (Wi-Fi) is common technology for indoor environments that use to estimate required distances, to be used for indoor localization. Due to multiple source of noise and interference with other signal, the receive signal strength (RSS) measurements unstable. The impression about targets environments should be available to estimate accurate targets location. The Wi-Fi fingerprint technique is widely implemented to build database matching with real data, but the challenges are the way of collect accurate data to be the reference and the impact of different environments on signals measurements. In this paper, optimum system proposed based on modify nearest point (MNP). To implement the proposal, 78 points measured to be the reference points recorded in each environment around the targets. Also, the case study building is separated to 7 areas, where the segmentation of environments leads to ability of dynamic parameters assignments. Moreover, database based on optimum data collected at each time using 63 samples in each point and the average will be final measurements. Then, the nearest point into specific environment has been determined by compared with at least four points. The results show that the errors of indoor localization were less than (0.102 m).

Acetylation of lysines on affinity-purification matrices to reduce co-digestion of bead-bound ligands v1

In mass-spectrometry-based interaction proteomics on-bead digestion protocols are commonly applied after affinity-enrichment due to their simplicity and high efficiency. However, on-bead digestion often leads to strong background signals due to co-digestion of the bead-bound ligands such as streptavidin or antibodies. We present an effective, rapid and low-cost method to specifically reduce the peptide signals from co-digested matrix ligands. A short pre-incubation of matrix beads with Sulfo-NHS-Acetate (S-NHS-Ac) leads to acetylation of free amines on lysine side-chains of the bead-bound ligands making them resistant to Lys-C-mediated proteolysis. After binding of bait proteins to the acetylated beads we employ a two-step digestion protocol with the sequential use of Lys-C protease for on-bead digestion followed by in-solution digestion with trypsin. The strong reduction of interfering ligand peptides improves signal strength and data quality for the peptides of interest in liquid chromatography mass spectrometry (LC-MS).

A method of pedestrian flow monitoring based on received signal strength

There is a wide demand for people counting and pedestrian flow monitoring in large public places such as scenic tourist areas, shopping malls, stations, squares, and so on. Based on the feedback from the pedestrian flow monitoring system, resources can be optimally allocated to maximize social and economic benefits. Moreover, trampling accidents can be avoided because pedestrian guidance is carried out in time. In order to meet these requirements, we propose a method of pedestrian flow monitoring based on the received signal strength (RSS) of wireless sensor networks. This method mainly utilizes the shadow attenuation effect of pedestrians on radio frequency (RF) signals of effective links. In this paper, a deployment structure of RF wireless sensor network is firstly designed to monitor the pedestrians. Secondly, the features are extracted from the wavelet decomposition of RSS signal series with a short time. Lastly, the support vector machine (SVM) algorithm is trained by an experimental data set to distinguish the instantaneous number of pedestrian passing through the monitoring point. In the case of dense and sparse indoor personnel density, the accuracy of the SVM model is 88.9% and 94.5%, respectively. In the outdoor environment, the accuracy of the SVM model is 92.9%. The experimental results show that this method can realize the high precision monitoring of the flow of people in the context of real-time pedestrian flow monitoring.

Bluetooth-Tracing RSSI Sampling Method as Basic Technology of Indoor Localization for Smart Grid

In recent years, Smart Grid have become the center of interest for IT companies and construction companies and various types of Smart Grids have been made currently available on the market. Yet, equipment is costly and it is not easy to convert existing equipment for Smart Grid application as they may require additional resources which could also inflict much costs. The extra costs involving the remodeling of existing housing structure and installment of new equipment can be avoided by using advanced wireless technologies. As an example, this book proposed an indoor localization system that adopts Bluetooth technology and uses RSSI (Received Signal Strength Indication) values for localization. Researchers have configured a system where the central control device will recognize all other devices or equipment in the system, communicate with each other, and respond to the commands or the information provided. However, despite the efforts of many researchers, existing RSSI-based indoor localization systems do not show a satisfactory level of accuracy such that we have devised a system that traces the trend in the RSSI samples.

IPWV estimation and data quality analysis from different GNSS antenna

Global Navigation Satellite System (GNSS) is widely used now days in variety of applications. The observation file for the near realtime estimation of Integrated Precipitable Water Vapour (IPWV) received at the ground-based receiver is mixed with ambiguities. Multi-path effects affect the positional accuracy as well as range from satellite to ground based receiver of the system. The designing of the antenna suppress the effect of multi-path, cycle slips, number of observations, and signal strength and data gaps within the data streams. This paper presents the preliminary data quality control findings of the Patch antenna (LeicaX1202), 3D Choke ring antenna (LeicaAR25 GNSS) and Trimble Zephyr antenna (TRM 39105.00). The results shows that choke ring antenna have least gaps in the data, cycle slips and multi-path effects along with improvement in IPWV. The signal strength and the number of observations are more in case of 3D choke ring antenna.

Preliminary performance evaluation and verification of digital terrestrial television signal propagation

This article presents the computer simulation and field test measurement results on Channel 29 for the preliminary performance evaluation and verification of the newly-installed Lesotho digital terrestrial television network based on DVB-T2 standard following the guidelines and techniques specified by the ITU-R BT.2035-2. It evaluates, at predetermined outdoor locations for fixed and mobile reception, parameters such as received signal strength, signal quality, bit-error rate (BER) and threshold-of-visibility (ToV) together with TV signal decoding (observation of screen artefacts) for quasi error-free reception. The results indicate that at over 97% of the test sites/points at the university town of Roma, the main Berea Plateau transmitter from the capital city (Maseru) broadcasts digital television service with enough signal level and quality to be properly decoded. The measured signal strength threshold ranges above -50 dBm for good reception, -64 dBm to -50 dBm for acceptable reception and -69 dBm to -64 dBm for poor reception. With the noise floor at about -73 dBm, the minimum required C/N of around 23 dB for good reception and about 4 dB for ToV have been recorded. The relative values of minimum required respective signal strength and signal quality for ToV obtained from the set-top box are 33% and 18% for stationary reception, while they give 37% and 20% for mobile reception.

Criteria for the reliability of optical coherence tomography measurements in patients with age-related cataract

Purpose. To determine optimal criteria for reliable optical coherence tomography (OCT) measurements in patients with age-related cataract. Material and methods. We examined 83 patients (83 eyes) with agerelated cataract before and after cataract surgery. The intensity of lens opacity was assessed by the Cirrus HD-OCT signal strength and Pentacambased Scheimpflug images analysis. Clinical cataract grading was performed according to the WHO classification. Preoperative measurement was considered reliable if its' difference with postoperative measurement did not exceed 5 ?m for the peripapillary retinal nerve fiber layer thickness (pRNFL) and 8 ?m for the central subfield thickness. Results. According to the ROC analysis, only the OCT signal strength allows to distinguish reliable OCT measurements: area under the ROC-curve (AUC) of the OCT signal strength was 0.815 (95% confidence interval 0.720–0.909) for the pRNFL and 0.756 (95% CI: 0.632–0.880) for the central subfield thickness. The best signal strength thresholds for reliable data were 5.5 for pRNFL and 4.5 for the central macular thickness (considering that the signal strength is measured in integers, these values should be rounded to 6 and 5 respectively). The rest of the studied parameters had AUC less than 0.6 so they cannot be used for evaluating OCT data. Conclusion. In patients with age-related cataract, only OCT signal strength can determine reliability of the OCT measurements. The lowest signal strength for reliable data on the Cirrus HD-OCT is 6 for pRNFL and 5 for centr al subfield thickness. Key words: optical coherence tomography, cataract, retina, nerve fiber layer, lens densitometry.