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Practical Estimation of the Maturity of Water Melon

西瓜成熟度的实用估算

基本信息

批准号：
60860027
负责人：
NISHIMURA Isao
金额：
$ 4.22万
依托单位：
KOBE UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60860027/
关键词：
Maturity of water Physical property of water melon Hitting sound and delivered accerelation NOtch filter method Power spectral density 論理演算農産物の物性打撃振動波形農産物生長と熟度

项目摘要

This research has carried about five years in our labaratory under the standpoint that the optimum harvesting time depends upon the matyrity of water melon. Two kinds of mearsing apparatus for estimating the optimum harvesting time are developed.1 Filter method : This appratus is composed with microphon ,notch filter to make the frequency and LED level meter to indicate the sound signal. When the frequency of the sound agrees with the frequency of the notch filter, the output level between just after filter and just before filter is pallel with maturity of the water melon. Previous research have dissolved the relation between the frequency and maturity of the water melon.2 Computer aided method : From the frequency data of the hitting sounds and delivered accerelation through the water melon and the physical data of the water melon, the maturity of the water melon is estimated. This proccesor is composed to microphon and its amplyfier to catch the hitting sound of the water melon,A-D comvertor to make sound data to digital data,16-bit one board computer system that analyses the data,calculates the power spectral density and calculates and estimates the maturity, is carried and LED idicator system indicates the estimating results. After the data of sound being A-D converted,the data is analysed to get the values of attack time,sustain time, release time and symmetry of the frequency. The power spectral density is calculated from the method of FFT and then evaluated and estimated the maturity of the water melon.

本研究在西瓜成熟度决定西瓜最佳采收期的观点下，进行了近五年的研究。研制了两种用于估计最佳收获期的测量装置。1滤波法：该装置由传声器、陷波器和LED电平计组成，陷波器用于频率的确定，LED电平计用于声音信号的指示。当声音的频率与陷波滤波器的频率一致时，滤波后和滤波前之间的输出水平与西瓜的成熟度平行。2计算机辅助方法：根据西瓜的物理特性和西瓜的敲击声频率数据，利用西瓜的敲击声频率数据和西瓜传递的加速度数据，对西瓜的成熟度进行估计。该处理器由麦克风及其放大器采集西瓜敲击声、A-D转换器将声音数据转换为数字数据、16位单板计算机系统进行数据分析、功率谱密度计算、成熟度计算和估计等组成，LED指示器系统显示估计结果。对声音数据进行A/D转换后，对数据进行分析，得到起音时间、持续时间、释放时间和频率对称性的数值。利用FFT方法计算西瓜的功率谱密度，进而对西瓜的成熟度进行评价和估计。