An autonomous and wireless pulse-amplitude modulated chlorophyll fluorometer

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Julian Reimer ◽  
Sebastian Stöcklin ◽  
Laura M. Comella ◽  
Peter Woias ◽  
Christiane Werner ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Plant Stress ◽  
Pulse Amplitude ◽  
Excitation Power ◽  
Custom Duty ◽  
Sensor Device ◽  
Invasive Method ◽  
Fluorescence Light ◽  
Relative Variable ◽  
Wireless Interface

Abstract Measuring chlorophyll fluorescence is an important tool in plant research, since it is a reliable non-invasive method for capturing photosynthetic efficiency of a plant and, hence, an indicator of plant stress/health. The principle of chlorophyll fluorometry is based on the optical illumination of a plant’s leaf at a certain wavelength, while simultaneously measuring the emitted fluorescence light intensity at a different optical wavelength. By relating the fluorescence light energy at small and large excitation power, conclusions on the efficiency of the photosystem and, therefore, on the plant’s photosynthesis capability can be drawn. Current mobile chlorophyll fluorometers are either (i) compact and energy efficient but limited in functionality and accuracy by omitting modulated measurement signals or (ii) sophisticated and precise with respect to the measurement, but with the drawback of extended weight, size, energy consumption and cost. This contribution presents a smaller, lighter and cheaper sensor device that can be built with sufficiently low energy consumption to be powered by energy harvesting while being light enough to be attached nearly anywhere such as tree branches. With a device cost below 250 €, the performance of the developed device is similar to more expensive commercial devices considering measurements of the relative variable fluorescence. Moreover, the sensor device provides a wireless interface in the European 868 MHz SRD band with up to 10 km of range in free space while just consuming 150 µW in receiving mode due to a custom duty cycling technique.

Simulating Game Applications in Mobile IPv6 Protocol

2012 ◽  
pp. 22-40
Author(s):  
Omar Raoof ◽  
Hamed Al-Raweshidy
Keyword(s):  
Energy Consumption ◽  
Decision Process ◽  
Access Point ◽  
Mobile Node ◽  
Mobile Ipv6 ◽  
Network Selection ◽  
Mobile Nodes ◽  
Ipv6 Protocol ◽  
Wireless Interface ◽  
The Right

This chapter proposes a novel game-based green interface/network selection mechanism that is an extension to the multi-interface fast-handover mobile IPv6 protocol and works when the mobile node has more than one wireless interface. The mechanism controls the handover decision process by deciding whether a handover is needed or not and helps the node to choose the right access point at the right time. Additionally, the mechanism switches the mobile nodes interfaces “ON” and “OFF” when needed to control the mobile node’s energy consumption and improves the handover latency.

scholarly journals Energy Efficient MAC Scheme for Wireless Sensor Networks with High-Dimensional Data Aggregate

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Seokhoon Kim ◽  
Hangki Joh ◽  
Seungjun Choi ◽  
Intae Ryoo
Keyword(s):  
Energy Efficiency ◽  
Energy Consumption ◽  
High Dimensional Data ◽  
Wireless Sensor ◽  
High Dimensional ◽  
Sink Node ◽  
Group Management ◽  
Mac Scheme ◽  
Sensor Device ◽  
Sensor Devices

This paper presents a novel and sustainable medium access control (MAC) scheme for wireless sensor network (WSN) systems that process high-dimensional aggregated data. Based on a preamble signal and buffer threshold analysis, it maximizes the energy efficiency of the wireless sensor devices which have limited energy resources. The proposed group management MAC (GM-MAC) approach not only sets the buffer threshold value of a sensor device to be reciprocal to the preamble signal but also sets a transmittable group value to each sensor device by using the preamble signal of the sink node. The primary difference between the previous and the proposed approach is that existing state-of-the-art schemes use duty cycle and sleep mode to save energy consumption of individual sensor devices, whereas the proposed scheme employs the group management MAC scheme for sensor devices to maximize the overall energy efficiency of the whole WSN systems by minimizing the energy consumption of sensor devices located near the sink node. Performance evaluations show that the proposed scheme outperforms the previous schemes in terms of active time of sensor devices, transmission delay, control overhead, and energy consumption. Therefore, the proposed scheme is suitable for sensor devices in a variety of wireless sensor networking environments with high-dimensional data aggregate.

scholarly journals Research of the properties of rocks during fragmenting and crushing in mechanical mills

2021 ◽  
pp. 81-87
Author(s):  
GOLIK Vladimir Ivanovich ◽  
Keyword(s):  
Energy Consumption ◽  
Raw Materials ◽  
Experimental Studies ◽  
Mining Industry ◽  
Pulse Amplitude ◽  
Resource Base ◽  
Crushed Material ◽  
Mineral Raw Materials ◽  
Systemic Crisis ◽  
The Impact

Relevance and purpose. The systemic crisis in the mining industry has weakened the provision of the industry with proven reserves of the main types of minerals, which has made the search for technological solutions in order to restore the lost potential of the mineral resource base. Methodology. Theoretical studies of the movement of the grinding charge in the grinding chambers of planetary mills are based on the postulate of the equivalence of the forms of movement of the charge in mills. Grinding equipment of a new technical level is being improved in the direction of increasing the intensity of the effect of grinding bodies on the crushed material. The aim of the study is to increase the intensity of the impact of grinding bodies on the crushed mineral raw materials while minimizing the energy consumption of processing processes. The goal is achieved by integrating analytical and experimental studies with elements of engineering forecasting and modeling of the results. Results and scope. The results of studying the properties of rocks and their changes as a result of crushing and grinding in mechanical mills are presented. Information about devices for measuring the parameters of shock pulses and the practice of their application is systematized on the example of geological differences of rocks. Bench studies have confirmed the theoretically substantiated phenomenon of shock pulse amplitude suppression. The role of the processes of crushing and grinding in mills in the technological chain of waste-free utilization of the tailings of the concentration of chemically exposed ores is detailed. Сonclusions. The phenomenon of increasing the intensity of the impact of grinding bodies on the crushed mineral raw materials with the same energy consumption of processing processes can be used in the modernization of technologies for the development of mineral deposits.

Development of an electronic device with wireless interface for measuring and monitoring residential electrical loads using the non-invasive method

2020 ◽  
Vol 13 (7) ◽  
pp. 1281-1298
Author(s):  
André Araújo Kuhn Pereira ◽  
Raimundo José Andrade Menezes ◽  
Aydin Jadidi ◽  
Pieter De Jong ◽  
Antonio Cezar de Castro Lima
Keyword(s):  
Electronic Device ◽  
Non Invasive ◽  
Invasive Method ◽  
Wireless Interface ◽  
Electrical Loads

scholarly journals Features and applications of a field imaging chlorophyll fluorometer to measure stress in agricultural plants

2020 ◽  
Author(s):  
Alexander I. Linn ◽  
Alexander K. Zeller ◽  
Erhard E. Pfündel ◽  
Roland Gerhards
Keyword(s):  
Chlorophyll Fluorescence ◽  
Plant Stress ◽  
Pulse Amplitude ◽  
Sensor Data ◽  
Stress Detection ◽  
Herbicide Resistant ◽  
Primary Stress ◽  
Field Estimation ◽  
Agricultural Plants ◽  
Imaging Sensor

Abstract Most non-destructive methods for plant stress detection do not measure the primary stress response but reactions of processes downstream of primary events. For instance, the chlorophyll fluorescence ratio Fv/Fm, which indicates the maximum quantum yield of photosystem II, can be employed to monitor stress originating elsewhere in the plant cell. This article describes the properties of a sensor to quantify herbicide and pathogen stress in agricultural plants for field applications by the Fv/Fm parameter. This dedicated sensor is highly mobile and measures images of pulse amplitude modulated (PAM) chlorophyll fluorescence. Special physical properties of the sensor are reported, and the range of its field applications is defined. In addition, detection of herbicide resistant weeds by employing an Fv/Fm-based classifier is described. The PAM-imaging sensor introduced here can provide in-field estimation of herbicide sensitivity in crops and weeds after herbicide treatment before any damage becomes visible. Limitations of the system and the use of a classifier to differentiate between stressed and non-stressed plants based on sensor data are presented. It is concluded that stress detection by the Fv/Fm parameter is suitable as an expert tool for decision making in crop management.

scholarly journals Test–retest reliability of pulse amplitude tonometry measures of vascular endothelial function: Implications for clinical trial design

2012 ◽  
Vol 17 (1) ◽  
pp. 29-36 ◽  
Author(s):  
Cindy E McCrea ◽  
Ann C Skulas-Ray ◽  
Mosuk Chow ◽  
Sheila G West
Keyword(s):  
Endothelial Function ◽  
Augmentation Index ◽  
Reactive Hyperemia ◽  
Clinical Trial Design ◽  
Pulse Amplitude ◽  
Future Research ◽  
Pulse Wave Amplitude ◽  
Invasive Method ◽  
Measure Change ◽  
Test Retest Reliability

Endothelial dysfunction is an important outcome for assessing vascular health in intervention studies. However, reliability of the standard non-invasive method (flow-mediated dilation) is a significant challenge for clinical applications and multicenter trials. We evaluated the repeatability of pulse amplitude tonometry (PAT) to measure change in pulse wave amplitude during reactive hyperemia (Itamar Medical Ltd, Caesarea, Israel). Twenty healthy adults completed two PAT tests (mean interval = 19.5 days) under standardized conditions. PAT-derived measures of endothelial function (reactive hyperemia index, RHI) and arterial stiffness (augmentation index, AI) showed strong repeatability (intra-class correlations = 0.74 and 0.83, respectively). To guide future research, we also analyzed sample size requirements for a range of effect sizes. A crossover design powered at 0.90 requires 28 participants to detect a 15% change in RHI. Our study is the first to show that PAT measurements are repeatable in adults over an interval greater than 1 week.

scholarly journals Global Trends of Usage of Chlorophyll Fluorescence and Projections for the Next Decade

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Alonso Zavafer ◽  
Leen Labeeuw ◽  
Cristian Mancilla
Keyword(s):  
Chlorophyll Fluorescence ◽  
Plant Stress ◽  
Pulse Amplitude ◽  
Pulse Amplitude Modulation ◽  
Global Trends ◽  
The Public ◽  
The Past ◽  
Scientific Opinion ◽  
Geographical Bias ◽  
Fast Rise

Chlorophyll fluorescence is the most widely used set of techniques to probe photosynthesis and plant stress. Its great versatility has given rise to different routine methods to study plants and algae. The three main technical platforms are pulse amplitude modulation (PAM), fast rise of chlorophyll fluorescence, and fast repetition rate. Solar-induced fluorescence (SIF) has also gained interest in the last few years. Works have compared their advantages and their underlying theory, with many arguments advanced as to which method is the most accurate and useful. To date, no data has assessed the exact magnitude of popularity and influence for each methodology. In this work, we have taken the bibliometrics of the past decade for each of the four platforms, have evaluated the public scientific opinion toward each method, and possibly identified a geographical bias. We used various metrics to assess influence and popularity for the four routine platforms compared in this study and found that, overall, PAM currently has the highest values, although the more recent SIF has increased in popularity rapidly during the last decade. This indicates that PAM is currently one of the fundamental tools in chlorophyll fluorescence.

scholarly journals An Energy-Efficient and Routing Approach for Position Estimation using Kalman Filter Techniques in Mobile WSNs

2015 ◽  
Vol 10 (4) ◽  
pp. 500
Author(s):  
Yezid Donoso ◽  
Germán A. Montoya ◽  
Fernando Solano
Keyword(s):  
Kalman Filter ◽  
Energy Consumption ◽  
Proper Time ◽  
Position Estimation ◽  
Channel Noise ◽  
Accurate Information ◽  
Mobile Sensor ◽  
Circular Trajectory ◽  
Sensor Device ◽  
Sensor Position

Mobile Wireless Sensor Networks is being an attractive field due to its applicability to an increasingly amount of mobile scenarios such as wild monitoring, disaster prevention, object guidance and health monitoring. In addition, since the sensors have limited batteries, data routing has to be planned strategically in order to extend the battery lifetime as much as possible [1] [2]. In this paper, we assume GPS free sensor devices, where considering a predictive technique to estimate the sensor position in a circular trajectory scenario can be useful to know when the sensor will be as close as possible to a sink, and then, help us to reduce the energy consumption by the fact of transmitting data at a short distance respect to the sink. In this paper, we propose an predictive algorithm based on Kalman filter techniques to estimate the proper time at which the sensor is close as much as possible to a sink, in order to reduce the energy consumption in the sensor. Specifically, we propose the usage of two Kalman Filters. One Kalman Filter is used for estimating the Received Signal Strength Indicator (RSSI) level based on several control packets received at the sensor device. This RSSI estimation indicates the distance from the mobile sensor device to the sink at a given time. The second Kalman Filter, based on the outputs from the first Kalman Filter, estimates the angular velocity and the angle of the mobile sensor device at a given time. Once this information is processed, it is possible to estimate the mobile sensor position in a circular trajectory in order to determine how much close is the mobile sensor device respect to the sink. In addition, the communication channel noise may affect the packet content, generating non-accurate information measurements at the receptor. For this reason, our proposal is evaluated under different noise channel levels and compared against a traditional technique. Our predictive routing algorithm shows better results in terms of distance accuracy to the sink and energy consumption in noisy communication channels.

scholarly journals Energy Conservation for Internet of Things Tracking Applications Using Deep Reinforcement Learning

Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 3261
Author(s):  
Salman Md Sultan ◽  
Muhammad Waleed ◽  
Jae-Young Pyun ◽  
Tai-Won Um
Keyword(s):  
Reinforcement Learning ◽  
Energy Consumption ◽  
Internet Of Things ◽  
Target Tracking ◽  
Short Term Memory ◽  
Tracking System ◽  
Sensor Selection ◽  
Battery Lifetime ◽  
Sensor Device ◽  
Tracking Model

The Internet of Things (IoT)-based target tracking system is required for applications such as smart farm, smart factory, and smart city where many sensor devices are jointly connected to collect the moving target positions. Each sensor device continuously runs on battery-operated power, consuming energy while perceiving target information in a particular environment. To reduce sensor device energy consumption in real-time IoT tracking applications, many traditional methods such as clustering, information-driven, and other approaches have previously been utilized to select the best sensor. However, applying machine learning methods, particularly deep reinforcement learning (Deep RL), to address the problem of sensor selection in tracking applications is quite demanding because of the limited sensor node battery lifetime. In this study, we proposed a long short-term memory deep Q-network (DQN)-based Deep RL target tracking model to overcome the problem of energy consumption in IoT target applications. The proposed method is utilized to select the energy-efficient best sensor while tracking the target. The best sensor is defined by the minimum distance function (i.e., derived as the state), which leads to lower energy consumption. The simulation results show favorable features in terms of the best sensor selection and energy consumption.

Malfunctional Reorganization in the Developing Limbo-Prefrontal System in Animals: Implications for Human Psychoses?

2001 ◽  
Vol 12 (1) ◽  
pp. 8-14
Author(s):  
Gertraud Teuchert-Noodt ◽  
Ralf R. Dawirs
Keyword(s):  
Prefrontal Cortex ◽  
Mental Disorders ◽  
Dentate Gyrus ◽  
Cognitive Functions ◽  
Experimental Approach ◽  
Regulatory Mechanisms ◽  
Hippocampal Dentate Gyrus ◽  
Non Invasive ◽  
Invasive Method ◽  
Activity Dependent

Abstract: Neuroplasticity research in connection with mental disorders has recently bridged the gap between basic neurobiology and applied neuropsychology. A non-invasive method in the gerbil (Meriones unguiculus) - the restricted versus enriched breading and the systemically applied single methamphetamine dose - offers an experimental approach to investigate psychoses. Acts of intervening affirm an activity dependent malfunctional reorganization in the prefrontal cortex and in the hippocampal dentate gyrus and reveal the dopamine position as being critical for the disruption of interactions between the areas concerned. From the extent of plasticity effects the probability and risk of psycho-cognitive development may be derived. Advance may be expected from insights into regulatory mechanisms of neurogenesis in the hippocampal dentate gyrus which is obviously to meet the necessary requirements to promote psycho-cognitive functions/malfunctions via the limbo-prefrontal circuit.

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