A Plant Leaf Geometric Parameter Measurement System Based on the Android Platform

Automatic and efficient plant leaf geometry parameter measurement offers useful information for plant management. The objective of this study was to develop an efficient and effective leaf geometry parameter measurement system based on the Android phone platform. The Android mobile phone was used to process and measure geometric parameters of the leaf, such as length, width, perimeter, and area. First, initial leaf images were pre-processed by some image algorithms, then distortion calibration was proposed to eliminate image distortion. Next, a method for calculating leaf parameters by using the positive circumscribed rectangle of the leaf as a reference object was proposed to improve the measurement accuracy. The results demonstrated that the test distances from 235 to 260 mm and angles from 0 to 45 degrees had little influence on the leafs’ geometric parameters. Both lab and outdoor measurements of leaf parameters showed that the developed method and the standard method were highly correlated. In addition, for the same leaf, the results of different mobile phone measurements were not significantly different. The leaf geometry parameter measurement system based on the Android phone platform used for this study could produce high accuracy measurements for leaf geometry parameters.

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Comparison between a vector multiport network analyzer and the national S-parameter: measurement system

Proceedings of Conference on Precision Electromagnetic Measurements Digest ◽

10.1109/cpem.1994.333411 ◽

2002 ◽

Cited By ~ 1

Author(s):

A. Ferrero ◽

F. Sanpietro ◽

U. Pisani ◽

L. Brunetti

Keyword(s):

Measurement System ◽

Parameter Measurement ◽

Network Analyzer ◽

S Parameter ◽

Multiport Network

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Using Facebook Ad Data to Track the Global Digital Gender Gap

10.31235/osf.io/rkvb3 ◽

2018 ◽

Author(s):

Masoomali Fatehkia ◽

Ridhi Kashyap ◽

Ingmar Weber

Keyword(s):

Mobile Phone ◽

Gender Gap ◽

Low Income ◽

Low Income Countries ◽

Gender Gaps ◽

Mobile Access ◽

Country Level ◽

Highly Correlated ◽

And Gender ◽

Official Data

Gender equality in access to the internet and mobile phones has become increasingly recognised as a development goal. Monitoring progress towards this goal however is challenging due to the limited availability of gender-disaggregated data, particularly in low-income countries. In this data sparse context, we examine the potential of a source of digital trace `big data' -- Facebook's advertisement audience estimates -- that provides aggregate data on Facebook users by demographic characteristics covering the platform's over 2 billion users to measure and `nowcast' digital gender gaps. We generate a unique country-level dataset combining `online' indicators of Facebook users by gender, age and device type, `offline' indicators related to a country's overall development and gender gaps, and official data on gender gaps in internet and mobile access where available. Using this dataset, we predict internet and mobile phone gender gaps from official data using online indicators, as well as online and offline indicators. We find that the online Facebook gender gap indicators are highly correlated with official statistics on internet and mobile phone gender gaps. For internet gender gaps, models using Facebook data do better than those using offline indicators alone. Models combining online and offline variables however have the highest predictive power. Our approach demonstrates the feasibility of using Facebook data for real-time tracking of digital gender gaps. It enables us to improve geographical coverage for an important development indicator, with the biggest gains made for low-income countries for which existing data are most limited.

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A high-precision camera operation parameter measurement system and its application to image motion inferring

IEEE Transactions on Broadcasting ◽

10.1109/11.920780 ◽

2001 ◽

Vol 47 (1) ◽

pp. 46-55 ◽

Cited By ~ 8

Author(s):

Wentao Zheng ◽

Y. Shishikui ◽

Y. Kanatsugu ◽

Y. Tanaka ◽

I. Yuyama

Keyword(s):

High Precision ◽

Measurement System ◽

Parameter Measurement ◽

Image Motion ◽

Operation Parameter

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Photoelectric parameter measurement system for chip-on-board wafer level packaging LEDs

Optics and Precision Engineering ◽

10.3788/ope.20162401.0039 ◽

2016 ◽

Vol 24 (1) ◽

pp. 39-44

Author(s):

裘燕青 QIU Yan-qing ◽

张刘刘 ZHANG Liu-liu ◽

陈苗根 CHEN Miao-gen ◽

王成群 WANG Cheng-qun

Keyword(s):

Measurement System ◽

Parameter Measurement ◽

Wafer Level ◽

Wafer Level Packaging

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Aircraft Platforms Vibration Measurement System Design and Verification

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.52-54.1620 ◽

2011 ◽

Vol 52-54 ◽

pp. 1620-1625

Author(s):

Shu Zhu ◽

Guang Lu Wang ◽

Hai Juan Chang

Keyword(s):

System Design ◽

Measurement System ◽

System Parameter ◽

Measurement Precision ◽

Parameter Measurement ◽

Vibration Measurement ◽

Environment Impact

For acquiring the data about how did the aircraft platforms environment impact on its equipment, designed a measurement system for measuring aircraft platform environment. How to select the measurement position, where did the system install and how to verify the system parameter measurement precision are introduced in this article. Finally, according to the using environment a environment test was designed to verify the environmental worthiness of the system.

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