Vol. 83, No. 2
Abstract
Prediction of Tomato Momotarou Haruka Flower-Clusters Occurrence using Cumulative Heat Unit and Cumulative Solar Radiation
[Keywords: tomato, Momotaro Haruka, flower-clusters occurrence, cumulative heat unit, solar radiation, mathematical models]
The relationship between the occurrence of tomato flower-clusters and environmental factors in greenhouse cultivation was examined and the mathematical models for the duration of flower-clusters occurrence (DFO) were established. Tomato (Solanum lycopersicum L. Var. Culta. Momotarou Haruka) was cultivated by medium culture from September 2018 to May 2019. During cultivation, stem elongation speed gradually increased to 25.68 cm/week after 58 days of transplanting. DFO took 5 to 18 days, while cumulative heat unit (CHU) and cumulative solar radiation (CSR) ranged from 86.5 to 279.1 ℃. day, and 31.6 to 230 MJ/m2, respectively. There was a strong significant relationship between CHU and DFO (r2＝0.93, RMSE＝0.73). Multiple regression analyses for DFO using CHU and CSR as explanatory variables indicated the high accuracy of estimation (r2＝0.94, RMSE＝0.71).
Quantitative Analysis of Tofu Microstructure with Different Coagulant Concentrations Based on Geometric Parameters and Haralick Texture Features
[Keywords: tofu, Young’s modulus, microstructure, geometric parameters, Haralick texture features]
The physical properties of tofu are greatly affected by microstructural properties, which have yet to be quantitatively analyzed. In this study, the microstructure of tofu made with 3 different coagulant concentrations was quantified using geometric parameters and Haralick texture features. As an indicator of hardness, Young’s modulus increased as coagulant concentration increased. Among the geometric parameters, the hole number increased while the mean size of the holes decreased with coagulant concentration increase, and porosity significantly decreased at the highest coagulant concentration. Among Haralick texture features, Sum Variance showed the highest loading in the principal component analysis with the highest value at middle coagulant concentration. Thus, microstructural characteristics of tofu have a potential to be an indicator of the physical qualities.
Electric Energy Demand Analysis and Energy Management Indices of Solar Light Plant Factories
[Keywords: solar light plant factory, air-source heat pump, electric energy demand analysis, energy conservation, energy management, energy management index, energy consumption intensity]
We analyzed the electric energy consumption characteristics of two solar light plant factories set up in Kanto, which cultivated tomatoes using air-source heat pumps, and proposed energy management indices. More than 85 % of the energy consumption was attributed to heat pumps and it highly correlated with outside temperature. The index, “monthly electric energy consumption per unit surface area of cultivation facility” was effective throughout the year, and the management standard value of index was obtained based on outside temperature. For stable production period with heating, “monthly electric energy consumption per unit surface area/monthly yield per unit floor area” was effective. To improve the index, measures from energy conservation and cultivation were thought necessary.
Development of a Simple and Safe Garlic Trimmer and its Performance
[Keywords: garlic, root trimming, work efficiency, simple, safe]
This study introduces a simple and safe machine to trim garlic roots. The trimmer's performance was evaluated experimentally. It utilizes a cone-shaped drill bit that is pressed against the garlic basal stem to trim the roots at different depths depending on a pre-adjusted depth adjuster. Since no individual technique is required for operation, the machine is safe and easy to operate even for people without skills. The machine can effectively trim a “well-shaped” garlic with six cloves and a round basal stem. However, for garlic that is not “well-shaped,” such as non-six-clove garlic or those with enlarged cloves, untrimmed parts may remain. According to the mean from simulation experiments, the efficiency was approximately 380 bulbs/h.
Measurement of Load Generated on the Handle of a Walking Tractor
――Load Generated during Tillage and Crashing――
[Keywords: walking tractor, safety, loop-shaped handle, handle load, tillage, crashing]
Cost Reduction, Labor Saving and Labor Deconcentration Effect by Using Seed Treatment Agent in Direct Sowing of Dry Rice Fields
[Keywords: rice, direct sowing of dry rice fields, seed treatment agent, cost reduction, labor saving, labor deconcentration]