scholarly journals Heave Motion Measurement by Adaptive Filter Based on Longuet-Higgins Wave Model

2017 ◽  
Vol 2017 ◽  
pp. 1-8
Author(s):  
Jiazhen Lu ◽  
Qiuwei Luo ◽  
Yanqiang Yang
Keyword(s):  
Adaptive Filter ◽  
Cutoff Frequency ◽  
Wave Model ◽  
Absolute Error ◽  
Average Error ◽  
Measurement Results ◽  
Highpass Filter ◽  
Normal Method ◽  
Heave Motion ◽  
Rough Sea

A method is proposed to obtain heave motion information based on the Longuet-Higgins wave model. The Longuet-Higgins wave model which is closer to the sea wave is introduced. Based on it, random process of the noise is analyzed and the highpass filter is designed to reduce errors. Then it is the key point in this article that an adaptive algorithm is put forward because of the complexity of the waves. The algorithm adjusts the cutoff frequency to reduce the amplitude attenuation of the filter by analyzing the wave. For the same reason the comprehensive parameter of the phase compensation can be also obtained by the algorithm. Simulation measurement results show that under the rough sea situation the maximum value of absolute error is 0.4942 m according to the normal method, the method is 0.1170 m, and the average error ratio of the rough sea test reduces to 3.89% from 12.54%, which demonstrates that the adaptive filter is more effective in measuring heave movement. A variety of simulation cases show that the adaptive filter can also improve the precision of the heave motion under different sea situations.

Half-mode substrate integrated plasmonic waveguide for filter and diplexer designs

2021 ◽  
Author(s):  
Yue Cui ◽  
Kai-Da Xu ◽  
Ying-Jiang Guo ◽  
Qiang Chen
Keyword(s):  
Communication Systems ◽  
Surface Plasmon Polariton ◽  
Simple Structure ◽  
Bandpass Filter ◽  
Cutoff Frequency ◽  
Plasmonic Waveguide ◽  
Wireless Communication Systems ◽  
Integrated Devices ◽  
Measurement Results ◽  
Via Holes

Abstract A half-mode substrate integrated waveguide (HMSIW) combined with spoof surface plasmon polariton (SSPP) structure is proposed to realize bandpass filter (BPF) characteristic and miniaturization, which is termed as the half-mode substrate integrated plasmonic waveguide (HMSIPW). Compared with the conventional HMSIW structure having identical cutoff frequency, this new design of HMSIPW not only supports SSPP modes, but also realizes a transversal size reduction of 19.4% and longitudinal reduction of more than 60%. Then, a diplexer based on two back-to-back placed HMSIPW BPFs is designed, and it has only one row of metallized via holes to further reduce the transversal size. The experimental prototypes of the filters and diplexer have been manufactured, and the measurement results agree well with simulation ones. Due to the size miniaturization and simple structure, the proposed designs will have many potentials in the integrated devices and circuits for wireless communication systems.

scholarly journals Evaluation of Mekong River commission operational flood forecasts, 2000–2012

2014 ◽  
Vol 18 (7) ◽  
pp. 2645-2656 ◽  
Author(s):  
T. C. Pagano
Keyword(s):  
Protective Action ◽  
Absolute Error ◽  
Probability Of Detection ◽  
Mekong River ◽  
Average Error ◽  
Wet Season ◽  
Phnom Penh ◽  
Mekong River Commission ◽  
Flood Level ◽  
Skill Scores

Abstract. This study created a 13-year historical archive of operational flood forecasts issued by the Regional Flood Management and Mitigation Center (RFMMC) of the Mekong River Commission. The RFMMC issues 1- to 5-day daily deterministic river height forecasts for 22 locations throughout the wet season (June–October). When these forecasts reach near flood level, government agencies and the public are encouraged to take protective action against damages. When measured by standard skill scores, the forecasts perform exceptionally well (e.g., 1 day-ahead Nash–Sutcliffe > 0.99) although much of this apparent skill is due to the strong seasonal cycle and the narrow natural range of variability at certain locations. Five-day forecasts upstream of Phnom Penh typically have 0.8 m error standard deviation, whereas below Phnom Penh the error is typically 0.3 m. The coefficients of persistence for 1-day forecasts are typically 0.4–0.8 and 5-day forecasts are typically 0.1–0.7. RFMMC uses a series of benchmarks to define a metric of percentage satisfactory forecasts. As the benchmarks were derived based on the average error, certain locations and lead times consistently appear less satisfactory than others. Instead, different benchmarks were proposed and derived based on the 70th percentile of absolute error over the 13-year period. There are no obvious trends in the percentage of satisfactory forecasts from 2002 to 2012, regardless of the benchmark chosen. Finally, when evaluated from a categorical "crossing above/not-crossing above flood level" perspective, the forecasts have a moderate probability of detection (48% at 1 day ahead, 31% at 5 days ahead) and false alarm rate (13% at 1 day ahead, 74% at 5 days ahead).

scholarly journals Design of Monitoring Tool Heartbeat Rate and Human Body Temperature Based on WEB

2018 ◽  
Vol 164 ◽  
pp. 01017 ◽  
Author(s):  
Jalinas ◽  
Wahyu Kusuma Raharja ◽  
Bobby Putra Emas Wijaya
Keyword(s):  
Heart Rate ◽  
Body Temperature ◽  
Human Body ◽  
Average Error ◽  
Web Pages ◽  
Test Results ◽  
Pulse Sensor ◽  
Measurement Results ◽  
Human Body Temperature ◽  
Error Percentage

The heart is one of the most important organs in the human body. One way to know heart health is to measure the number of heart beats per minute and body temperature also shows health, many heart rate and body temperature devices but can only be accessed offline. This research aims to design a heart rate detector and human body temperature that the measurement results can be accessed via web pages anywhere and anytime. This device can be used by many users by entering different ID numbers. The design consists of input blocks: pulse sensor, DS18B20 sensor and 3x4 keypad button. Process blocks: Arduino Mega 2560 Microcontroller, Ethernet Shield, router and USB modem. And output block: 16x2 LCD and mobile phone or PC to access web page. Based on the test results, this tool successfully measures the heart rate with an average error percentage of 2.702 % when compared with the oxymeter tool. On the measurement of body temperature get the result of the average error percentage of 2.18 %.

scholarly journals A Device to Measure a Smoker’s Puffing Topography and Real-Time Puff-By-Puff “Tar” Delivery

2014 ◽  
Vol 26 (2) ◽  
Author(s):  
Sandra J. Slayford ◽  
Barrie E. Frost
Keyword(s):  
Real Time ◽  
Light Emitting Diode ◽  
Absolute Error ◽  
Average Error ◽  
Light Emitting ◽  
Light Obscuration ◽  
Test Study ◽  
Added Benefit ◽  
Volume Characteristics ◽  
The Relationship

AbstractA device for measuring the flow, duration and volume characteristics of human puffing behaviour when smoking cigarettes is described. Cigarettes are smoked through a holder comprising a measured pressure drop across a critical orifice. The holder also contains a Light Emitting Diode (LED) and photodetector that measures light obscuration in order to estimate nicotine-free dry particulate matter (NFDPM, “tar”) delivery. All data are recorded on a puff-by-puff basis and displayed in real time. These NFDPM estimates are known as optical “tar” (OT), and are derived from the calibration of the OT measurement versus gravimetric NFDPM yields of cigarettes under a range of smoking regimes. In a test study, puff volumes from 20-80 mL were recorded to ± 6.0% of a pre-set volume, with an absolute error of 4.7 mL for an 80 mL volume drawn on a lit cigarette, and an average error of less than 2.0 mL across the range 20-80 mL. The relationship between NFDPM and OT was linear (R2 = 0.99) and accurate to ± 1.3 mg per cigarette over the range 1-23 mg per cigarette. The device provides an alternative to the widely used part filter methodology for estimating mouth level exposure with an added benefit that no further laboratory smoking replication or analysis is required. When used in conjunction with the part filter methodology, the puffing behaviour recorded can explain anomalies in the data while providing a second independent estimate.

Compact LowPass Filter with Wide StopBand Using Non-Uniform Microstrip Resonant Cells

2012 ◽  
Vol 263-266 ◽  
pp. 15-19
Author(s):  
Yan Liang ◽  
Xiao Ming Wu ◽  
Bi Hua Tang ◽  
Yong Le Wu
Keyword(s):  
Microstrip Line ◽  
Photonic Bandgap ◽  
Impedance Matching ◽  
Stop Band ◽  
Cutoff Frequency ◽  
Harmonic Suppression ◽  
Lowpass Filter ◽  
Measurement Results ◽  
Better Than

In this paper, a novel compact microstrip lowpass filter is designed. The proposed filter which is etched on the 50 Ω microstrip line consists of four non-uniform 1-D microstrip photonic bandgap (PBG) cells with different cutoff frequency.. The demonstration lowpass filter with 2.2 GHz cutoff frequency is designed, fabricated and measured. The measurement results show that the band rejection effect is better than -20 dB from 2.8 GHz to 10 GHz, the insertion is less than 2 dB, and the length of filter is 5.6 cm long. Compared with the conventional filter, the proposed filter has smaller size. Meanwhile, it overcomes the problems of narrow stop-band and low harmonic suppression. Furthermore, the impedance matching is not need to be considered. This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

Definition of Performance Requirements and Test Cases for Offshore/Subsea Winch Drive Systems With Digital Hydraulic Motors

2019 ◽  
Author(s):  
Sondre Nordås ◽  
Morten K. Ebbesen ◽  
Torben O. Andersen
Keyword(s):  
Force Control ◽  
Drive System ◽  
Test Cases ◽  
Performance Requirements ◽  
Hydraulic Motors ◽  
Constant Tension ◽  
Drive Systems ◽  
Definition Of ◽  
Heave Motion ◽  
Rough Sea

Abstract A subsea crane is normally mounted on a floating vessel and equipped with a winch system. The crane can operate in water down to 3000 m. The vessel tends to move up and down due to waves. This heave motion makes offshore lifting operations challenging. In order to ease the winch operation in rough sea, the winch can be equipped with additional systems like active heave compensation and constant tension. In active heave compensation and constant tension system, both motion and force control of the winch are important. This paper presents a digital displacement winch drive system and gives a description of challenges related to subsea lifting operations. The operation challenges are used to design a set of test cases for evaluating the performance of the digital displacement winch drive system.

Research on Dot Gain Compensation Curve Algorithm Model

2012 ◽  
Vol 200 ◽  
pp. 627-631 ◽  
Author(s):  
Li Li Si ◽  
Feng Xian Sang ◽  
Zhen Liu
Keyword(s):  
New Method ◽  
Average Error ◽  
Dot Gain ◽  
Gain Compensation ◽  
Normal Method ◽  
Compensation Curve

To make the dot gain compensation curve more precise, this paper analyzes the methods already used and then propose a new method. We implement this new method and the old ones respectively through MATLAB, and get their dot gain compensation curves. At the same time, the average error and variance were counted to test their precision. The results show that the new method can apparently improve the precision and reduce the error. The average error of the normal method is 2.96% while it is reduce to 1.56% by the new method.

scholarly journals Root mean square error (RMSE) or mean absolute error (MAE)? – Arguments against avoiding RMSE in the literature

2014 ◽  
Vol 7 (3) ◽  
pp. 1247-1250 ◽  
Author(s):  
T. Chai ◽  
R. R. Draxler
Keyword(s):  
Root Mean Square Error ◽  
Mean Square Error ◽  
Root Mean Square ◽  
Model Evaluation ◽  
Mean Absolute Error ◽  
Evaluation Studies ◽  
Model Performance ◽  
Absolute Error ◽  
Average Error ◽  
Mean Square

Abstract. Both the root mean square error (RMSE) and the mean absolute error (MAE) are regularly employed in model evaluation studies. Willmott and Matsuura (2005) have suggested that the RMSE is not a good indicator of average model performance and might be a misleading indicator of average error, and thus the MAE would be a better metric for that purpose. While some concerns over using RMSE raised by Willmott and Matsuura (2005) and Willmott et al. (2009) are valid, the proposed avoidance of RMSE in favor of MAE is not the solution. Citing the aforementioned papers, many researchers chose MAE over RMSE to present their model evaluation statistics when presenting or adding the RMSE measures could be more beneficial. In this technical note, we demonstrate that the RMSE is not ambiguous in its meaning, contrary to what was claimed by Willmott et al. (2009). The RMSE is more appropriate to represent model performance than the MAE when the error distribution is expected to be Gaussian. In addition, we show that the RMSE satisfies the triangle inequality requirement for a distance metric, whereas Willmott et al. (2009) indicated that the sums-of-squares-based statistics do not satisfy this rule. In the end, we discussed some circumstances where using the RMSE will be more beneficial. However, we do not contend that the RMSE is superior over the MAE. Instead, a combination of metrics, including but certainly not limited to RMSEs and MAEs, are often required to assess model performance.

scholarly journals SENSOR SYSTEM DESIGN FOR PROPELLER TEST BENCH

Vortex ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 37
Author(s):  
Nurul Ihsan ◽  
Denny Dermawan ◽  
Lazuardy Rahendra P
Keyword(s):  
System Design ◽  
Test Bench ◽  
Performance Testing ◽  
Sensor System ◽  
Average Error ◽  
Test Results ◽  
Wood Type ◽  
Error Factor ◽  
Measurement Results ◽  
Sensor System Design

The sensor system is a system that functions to detect signals that come from changes in energy such as electrical energy, physical energy, chemical energy, biological energy, mechanical energy, and so on. The propeller test bench is an propeller performance testing platform prior to propeller installation on an aircraft to ensure engine suitability. The purpose of this design is to test the performance capability of the engine with the right sensor system measurement tool so that it can generate the value of thrust, rpm speed, and the temperature of an engine which will be designed to be used in the learning process to support propulsion practicum activities. The method used in this research is an experimental method of sensor system design. The design of the sensor system consists of a tachometer as a rpm measurement sensor, a thermostat as a sensor to measure the temperature of the propeller spool and temperature of the engine fin, and also a load cell as a sensor to measure the thrust value.The sensor system test results were then validated using the measurement results by the sensor manufacturer. The test was carried out on a wood-type propeller measuring 22 x 8 chords 4,5 cm and 5 cm. Based on the test results, it is known that the chord wood type propeller is 4,5 cm, at the maximum rpm is 7021.7, the resulting thrust value is 6.75. In testing the 5cm chord wood type propeller shows the maximum speed of 6977.5 produces a thrust of 6.95. Validation was carried out on the measurement results of rpm and thrust, the average error factor obtained for 4,5 cm chord wood type propeller was 0.783%, while for 5 cm chord wood type propeller the average error factor obtained was 1.0582%. From the resulting average error, it can be concluded that the measuring instrument for this sensor system has good accuracy

scholarly journals Evaluation of Mekong River Commission operational flood forecasts, 2000–2012

2013 ◽  
Vol 10 (11) ◽  
pp. 14433-14461 ◽  
Author(s):  
T. C. Pagano
Keyword(s):  
Protective Action ◽  
Absolute Error ◽  
Probability Of Detection ◽  
Mekong River ◽  
Average Error ◽  
Wet Season ◽  
Phnom Penh ◽  
Mekong River Commission ◽  
Flood Level ◽  
Skill Scores

Abstract. This study created a 13 yr historical archive of operational flood forecasts issued by the Regional Flood Management and Mitigation Center (RFMMC) of the Mekong River Commission. The RFMMC issues 1 to 5 day-ahead daily deterministic river height forecasts for 22 locations throughout the wet season (June–October). When these forecasts reach near Flood Level, government agencies and the public are encouraged to take protective action against damages. When measured by standard skill scores, the forecasts perform exceptionally well (e.g. 1 day-ahead Nash–Sutcliffe > 0.99) although much of this apparent skill is due to the strong seasonal cycle and the narrow natural range of variability at certain locations. 5 day-ahead forecasts upstream of Phnom Penh typically have 0.8 m error standard deviation, whereas below Phnom Penh the error is typically 0.3 m. The Coefficients of Persistence for 1 day-ahead forecasts are typically 0.4–0.8 and 5 day-ahead forecasts are typically 0.1–0.7. RFMMC uses a series of benchmarks to define a metric of Percentage Satisfactory forecasts. As the benchmarks were derived based on the average error, certain locations and lead-times consistently appear less satisfactory than others. Instead, different benchmarks were proposed and derived based on the 70th percentile of absolute error over the 13 yr period. There are no obvious trends in the Percentage of Satisfactory forecasts from 2002–2012, regardless of the benchmark chosen. Finally, when evaluated from a categorical "crossing above/not-crossing above flood level" perspective, the forecasts have a moderate probability of detection (48% at 1 day-ahead, 31% at 5 day-ahead) and false alarm rate (13% at 1 day-ahead, 74% at 5 days-ahead).

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