Measured Research Articles

ESTIMASI BIOMASSA VEGETASI KEBUN RAYA BOGOR MENGGUNAKAN KOMBINASI CITRA WORLDVIEW-2 DAN ALGORITMA PEMELAJARAN MESIN

An effective and efficient measurement method is required for estimating the vegetation biomass of an area with high canopy density. The combination of WorldView-2 imagery and machine learning algorithms can be an alternative approach for estimating vegetation biomass in Bogor Botanic Gardens. The research aimed to determine the variables from WorldView-2 imagery that can be used to estimate the vegetation biomass of Bogor Botanic Gardens, to identity several types of machine learning algorithms that produce the best prediction in estimating vegetation biomass in the field, to estimate and to map vegetation biomass in Bogor Botanic Gardens. The variables that had a significant correlation with biomass were NIR-reflectance, Blue-Correlation, Green-Correlation, NIR-Mean, and NIR-Variance. The NIR-Mean variable was the most important variable for estimating vegetation biomass. The random forest algorithm produced the best model for estimating vegetation biomass with r, PBIAS, RMSE, MAE and RSR values of 0,83, -11,51%, 185,47 Mg/ha, 139,43 Mg/ha, and 0,56 respectively. The estimated vegetation biomass of the Bogor Botanic Gardens had a range from 6,27 to 1.576,90 Mg/ha with an average of 183,96 Mg/ha and total biomass of 13,23 Gg. The combination of WorldView-2 imagery and the Random Forest algorithm produced a good predictive model compared to Artificial Neural Network and Support Vector Machine for estimating the vegetation biomass of Bogor Botanic Gardens. Bogor Botanic Gardens has a very important role in climate change mitigation, especially for the Bogor City.

Development of a novel particle mass spectrometer for online measurements of refractory sulfate aerosols

Sulfate aerosols are ubiquitous in the atmosphere. Ammonium sulfate (AS) is generally the dominant form of sulfate aerosols in urban air, whereas potassium sulfate (PS), sodium sulfate (SS), magnes...

A Study on the Measurement of Half-life for the 179Re Isotope Produced by a 100 MeV ProtonNuclear Reaction

A Study on the Measurement of Half-life for the 179Re Isotope Produced by a 100 MeV ProtonNuclear Reaction

An innovative liquid metal-based pressure sensor with its application in geotechnical engineering

In this paper, a monitoring system containing a novel liquid metal-based pressure sensor and remote interactive monitoring devices are fabricated to monitor stress in geotechnical engineering. The pressure sensor with the dimension of 34 mm × 34 mm is designed and manufactured, which is mainly composed of 40CrMoV alloy steel shell, polydimethylsiloxane (PDMS) and liquid metal gallium indium alloy (EGaIn). It has the characteristics of high stability, can greatly improve the measurement range of the pressure sensor (0 to 20 MPa), and its resistance variation is from 0 mΩ to 800 mΩ. In addition, the linear regression analysis is carried out to verify the linear relationship between the resistance of sensor and the applied pressure. It is found that the performance of the pressure sensor is fine through experiments with three different loading rates and fatigue experiments. The remote interactive monitoring device can be suitable for the field monitoring environment, which is composed of monitoring stations (MS), remote communication base stations (RCBS) and indoor working platform. Finally, the monitoring system is successfully applied to the field measurements in geotechnical engineering, and the field monitoring data are in good agreement with the numerical results.

Automated UAV based multi-hazard assessment system for bridges crossing seasonal rivers

An automated unmanned aerial vehicle (UAV) based multi-hazard performance assessment system was developed to respond to rapid performance evaluation and performance prediction needs for river crossing reinforced concrete (RC) bridges. In the developed system, firstly the seasonally acquired UAV measurements were used to obtain the three-dimensional (3D) digital elevation models (DEMs) of the river bed. In conjunction with the flood simulation, the hydraulic model was verified with the previous flood event which corresponded to Q50 and the scour depths after a probable flood (Q500) were predicted by HEC-RAS software. Afterward, the 3D finite element model (FEM) of the bridge was constituted automatically with the developed code considering the scoured piles. The flood loads were exerted on the modeled bridge with regard to the HEC-RAS flood inundation map and relevant water depth estimations around the bridge piers. For the seismic evaluation, nonlinear time history analyses (THA) were conducted by using several scaled earthquake acceleration records that were acting in both principal axes of the bridge simultaneously as compatible with the region seismicity. The Bogacay-II Bridge that was located in Antalya, Turkey was selected as the case study. In the analyses, as the scour depth increased, the lateral displacements and the pile internal forces were observed to increase while the pier column internal forces kept approximately constant. Thus, it was monitored that the seismic displacement and load demands migrated from pier columns to piles with increasing scour. Therefore, the applicability of the proposed system was verified using the case study bridge.

Implementation of SHM system for Hangzhou East Railway Station using a wireless sensor network

Structural health monitoring (SHM) is facilitated by new technologies that involve wireless sensor networks (WSNs). The main benefits of WSNs are that they are distributed, are inexpensive to install, and manage data effectively via remote control. In this paper, a wireless SHM system for the steel structure of Hangzhou East Railway Station in China is developed, since the state of the structural life cycle is highly complicated and the accompanying internal force redistribution is not known. The monitoring system uses multitype sensors, which include stress, acceleration, wind load, and temperature sensors, as the measurement components for the structural features, construction procedure, and on-site environment. The sensor nodes communicate with each other via a flexible tree-type network. The system that consists of 323 sensors is designed for the structure, and the data acquisition process will continue throughout its whole life cycle. First, a full-scale application of SHM using a WSN is described in details. Then, it focuses on engineering practice and data analysis. The current customized WSN has been demonstrated to have satisfactory durability and strong robustness; hence, it well satisfies the requirements for multi-type sensors to operate in a large area. The data analysis results demonstrate that the effects of the construction process and the environment on the super-large-scale structure have been captured accurately. Those effects include the stress variation throughout the construction process, the dynamic responses that are caused by passing trains, the strain variation caused by temperature change over the long term, and the delay in the wind-pressure history.

Settlement prediction for footings based on stress history from V-S measurements

A settlement prediction method based on shear wave velocity measurements and soil nonlinearity was recently developed and verified by means of centrifuge tests. However, the method was only applicable to heavily overconsolidated soil deposits under enlarged yield surfaces. In this study, the settlement evaluation method was refined to consider the stress history of the sublayer, based on an overconsolidation ratio evaluation technique, and thereby incorporate irrecoverable plastic deformation in the settlement calculation. A relationship between the small-strain shear modulus and overconsolidation ratio, which can be determined from laboratory tests, was adopted to describe the stress history of the subsurface. Based on the overconsolidation ratio determined, the value of an empirical coefficient that reflects the effect of plastic deformation over the elastic region is determined by comparing the overconsolidation ratio with the stress increment transmitted by the surface design load. The refined method that incorporate this empirical coefficient was successfully validated by means of centrifuge tests, even under normally consolidated loading conditions.

Methodology and Guidelines for Selecting Measurement Boundaries and Influence Variables for Analyzing and Evaluating Energy Usage in Demonstration ESS-Based Distribution and Logistics Facilities

Methodology and Guidelines for Selecting Measurement Boundaries and Influence Variables for Analyzing and Evaluating Energy Usage in Demonstration ESS-Based Distribution and Logistics Facilities

Quality assurance in radon SSNTD measurements : PHE experience

Quality assurance in radon SSNTD measurements : PHE experience

Beef Production on Rotationally Grazed F1 Pennisetum Hybrid and Elephant Grass (Pennisetum Purpureum Schum.) Pastures

Comparative studies of elephant grass and the F1 hybrids between the 'maiwa' cultivar of millet ( Pennisetum americanum ) and elephant grass ( P. purpureum ) indicated a superiority in quality of the hybrids. To ascertain this potential superiority animal performance was measured by estimating beef production on F1 Pennisetum hybrid and elephant grass pastures consisting of random mixtures of genotypes which were grazed from July 28 to December 6, 1972 (132 days) by 18 to 24 months old White Fulani (Bunaji) Zebu heifers. Each pasture was divided into six 0.07-ha paddocks which were grazed in intervening rest periods of 30 to 35 days. Total liveweight gains per hectare, of animals grazing F1 Pennisetum hybrid and elephant grass pastures were 246.71 and 171.77 kg respetively. Mean daily liveweight gain per 100 kg body weight of animals on the F1 Pennisetum hybrid pasture was 0.18 kg of animals grazing elephant grass. Dry matter (DM) utilisation and average daily intake of the F1 hybrids and elephant grass were respectively, 46 and 35% and 2.2 and 2.0% of body weight while 11.71 kg and 15.85 kg of F1 Pennisetum hybrids and elephant grass, respectively, were consumed per kg of liveweight gain. The superior performance of animals grazing F1 Pennisetum hybrids was attributed to the higher intake and more efficient conversion of the hybrids. Stand mortality of F1 Pennisetum hybrids and elephant grass at the end of the study were 25 and 15%, respectively. greater animal output can be expected from F1 Pennisetum hybrids selected for improved DM production quality and plant persistence.

BIOMETRIC VERIFICATION SYSTEM BASED ON HAND GEOMETRY

Biometric systems are widely used in medium and low security applications. Verification systems based on the geometry of the hand utilize some geometrical characteristics of the hand including measurements of fingers, shape of the palm, etc. In this work, we have developed an unconstrained and contact-based hand geometry verification system, using a combination of length and width of fingers. New measurements at different points of fingers were introduced in this paper to improve the performance of the recognition of persons. A total of 135 hand images were enrolled in this study. The Euclidean distance was used as a similarity function for different values of threshold. The proposed method was compared to state-of-the-art approaches. The results obtained reveal the high performance of the proposed approach and outperformed the existing methods with an accuracy of Acc = 98.67%.

Camera calibration based on color-coded phase-shifted fringe

Aiming at the low adaptability of blurring noise of target feature points in traditional calibration methods, a calibration method based on the color-coded phase-shifted fringe is proposed. Using a liquid crystal display panel as the calibration target, horizontal and vertical color-coded phase-shifted stripes are displayed in sequence; the orthogonal phase-shifted stripes are obtained by separating color channels; based on the phase-shifteg theory, the intersections of the orthogonal phase truncation lines are calculated as the feature points. After changing the target position multiple times and extracting feature points, the plane-based camera calibration technique is applied to realize the calibration of both the single camera and the binocular system. Furthermore, color-coded phase-shift circles are added to four corners of the target pattern to automatically extract and sort feature points. Accordingly, the efficiency of calibration is promoted. The experimental results indicate that when the target image is blurred, the reprojection error of the single-camera calibration is 0.15 pixels, and the standard deviation of the binocular system measurement after calibration is 0.1 mm.

A Measurement Method for Cervical Neural Foraminal Stenosis Ratio using 3-dimensional CT

A Measurement Method for Cervical Neural Foraminal Stenosis Ratio using 3-dimensional CT

Delay spread measurement and analysis in 3 GHz and 6 GHz indoor environments

Delay spread measurement and analysis in 3 GHz and 6 GHz indoor environments

The New Approach To Assessing The Marketing Effectiveness of Indonesian Firms

This study attempted to revise Philips Kotler’s marketing effectiveness model to diagnose and offer managerial implications for Indonesia marketing practices. Nineteen Indonesian firms, divided into ten manufacturing and nine service sectors, were examined to assess their level if marketing effectiveness. By industry, this firms were further divided into five categories; electronics, machinery, chemicals, finance and service-oriented. The five marketing effectiveness attributes – strategy, organization, operations, personal, and information system – along with accompanying factor components were incorporated into the measurement of the marketing effectiveness. The findings showed that manufacturing sector firms were less effective in marketing operations than the service sector firms. In both sectors, relative to the predetermined factor importance weights, the Indonesians firms were found to under perform in planning and controlling functions. Managerial implications regarding the underperforming marketing functions and future recommendations are offered.

Interfacial Behavior of Aqueous Solutions of Cetyltrimethylammonium Bromide (CTAB), Additives and Their Mixtures: The Experimental and Modeling Study

In the present investigation, firstly, the surface tension measurements were conducted for aqueous solutions of cetyltrimethylammonium bromide, acetonitrile, and tetrahydrofuran by using a pendant drop apparatus at the temperature of 298.15 K and ambient pressure. Then a thermodynamic model was used and successfully reproduced the surface tension values. The percent of the average absolute deviation for surface tension was 0.667. The surface tensions of mixed aqueous solutions of (cetyltrimethylammonium+additives) were measured at various concentrations. Then, the values of critical micelle concentrations were measured based on surface tension and conductivity. The percent of the average absolute deviation of the thermodynamic model was 5.05, proving that the model successfully predicts the surface tension for aqueous mixed solutions of (cetyltrimethylammonium+additives). The presence of additives decreases the surface coverage of cetyltrimethylammonium and increases the critical micelle concentration values.

A Study on Applicability Evaluation of digital Photogrammetry for Settlement Measurement of Soil Contaminated with Heavy Metals

A Study on Applicability Evaluation of digital Photogrammetry for Settlement Measurement of Soil Contaminated with Heavy Metals

Our Latest COVID-19 Coverage

Dear readers,This week, NEJM Journal Watch covered COVID-19–related topics including bamlanivimab in the outpatient setting, trends in COVID-19

Breeding Bird Occurrence Across a Gradient of Graminoid- to Shrub-Dominated Fens and Fire Histories

Population declines of birds affiliated with grasslands and grass-shrub habitats have been identified as a critical conservation concern. The effects of woody encroachment into grassland-dominated systems, which may contribute to species declines, has been examined mainly in upland systems. We examined occurrence of bird species across a gradient of graminoid- to shrub-dominated wetlands in the Upper Peninsula of Michigan and describe the habitat characteristics associated with their probability of occurrence at segment (100 × 100 m) and landscape (200 m buffer) scales. Because fire can suppress woody encroachment, we also examined the role of fire history, extending from 50 y on birds and habitat characteristics. We focused on seven species closely affiliated with grassland and grass-shrub habitats, but also found in wetlands: Sedge Wren (Asio flammeus), LeConte's Sparrow (Ammodramus leconteii), Savannah Sparrow (Passerculus sandwichensis), Bobolink (Dolichonyx oryzivorus), Common Yellowthroat (Geothlypis trichas), Swamp Sparrow (Melospiza georgiana), and Alder Flycatcher (Empidonax alnorum). We used nonparametric, multiplicative regression models to relate habitat variables and fire history to probability of species occurrence. Unlike studies in upland grasslands, none of the top models included measures of litter or graminoid height, and the highest probability of occurrence often was where graminoid cover was at intermediate rather than highest levels. Measures of woody cover or structure were important to all seven species modeled. We observed few clear differences in habitat metrics across fire history categories beyond the first year of burning. Years since last burned was in the best model for four of the seven species, despite high variability of habitat metrics within fire history categories; those species were more likely to occur in segments burned 15–19 y earlier. Infrequent light- to moderate-severity fires in fens had little effect on focal species occurrence beyond the first year after burning and little long-term effect to suppress woody cover.

What Is the Optimal Way to Measure Immunity to SARS-CoV-2?

Several serologic assays are available for detecting antibody responses to SARS-CoV-2 infection; however, their sensitivity and specificity are limited