SASJ - The Society of Agricultural Structures, Japan

Archive - Abstract

This study evaluates the effectiveness and operational cost of a newly developed "Compost Heating System" designed to enhance composting efficiency in cold regions. During rigorous winter tests, where temperatures dropped below -20 °C, the system successfully facilitated smooth composting processes, effectively mitigating the delays and stagnation typically observed during cold seasons. Even after the compost was moved to areas without the heating system, the temperature continued to rise similarly, indicating the system's significant contribution to the overall composting process. Economically, the system operates at 1402 yen per unit per day, a comparatively low cost compared to traditional methods that rely on heated air blown through ventilation pipes. These results strongly suggest that the Compost Heating System offers a practical and cost-effective solution for enhancing composting performance during severe winters, making it a promising advancement in the management of composting facilities in cold climates.

Keywords: composting, winter, heating system

Technical Papers (Japanese)
Taste Evaluation of Edamame, the Immature Seed of the Soybean Using Near-Infrared Spectroscopy
Shinsuke Furuno, Naoko Kijima and Motoyasu Natsuga

The feasibility of applying calibrations to estimate sucrose and free amino acid content in edamame, the immature seed of the soybean with pods　using near-infrared spectroscopy was investigated across models. Applying calibrations from the old model (Infratec1241) to the current model (InfratecNOVA) revealed no practical issues for either content estimation, confirming the applicability of the calibrations with bias corrections. Sensory evaluations were conducted to establish criteria for sucrose and free amino acid content in edamame produced in Yamagata Prefecture. Sample groups (two varieties × five levels) with varying taste profiles were analyzed. Results confirmed that the content range identified by Sue et al. (2009, J. Jpn. Soc. Agric. Mach. 71 (6) 98-105) as “adequate for brown-haired edamame” is also suitable for defining “proper eating quality for edamame from Yamagata Prefecture.” To assess the eating quality of brown-headed edamame across production sites, a wide-area survey was conducted in the Shonai region, Yamagata Prefecture. Among 249 samples, 92% fell within the range representing “proper eating quality for edamame from Yamagata Prefecture.”

Keywords:edamame, optical sensor, sucrose, free amino acid, near-infrared spectroscopy

Notes (Japanese)
Environmental Measurement System with Sensor Failure Detection and Abnormal Output Value Correction Functions for Greenhouse Horticulture
Yuta OHASHI, Ryota TSUCHIYA, Masahisa ISHII, Hirotaka OBO, Kotaro SEKI, and Hideki MORIYAMA

Greenhouses with dense crops, in particular, are susceptible to high temperatures and humidity, which can quickly deteriorate various environmental sensors. Therefore, a sensing system with sensor error detection and correction functions is essential to maintain stable environmental measurements and control in greenhouses. In this study, we developed a temperature and humidity sensing system with sensor error detection and error output value correction functions using multiple (three or more) sensors for each environmental parameter. The system detects sensor failures and identifies the faulty sensor by comparing the measurements from all sensors. It then outputs the average of the remaining sensors’ readings, excluding the faulty sensor’s values, ensuring continuous accurate environmental measurements. Sensor degradation is assessed based on the coefficient of variation of the sensor readings, assuming that an increase in variation indicates degradation. To test the system, the sensor malfunctions were simulated. The system successfully identified the faulty sensors and provided corrected values. The coefficient of variation, used as an indicator of sensor degradation, increased following the simulated malfunctions. In conclusion, this sensing system can prevent instability in environmental measurements and control greenhouse horticulture due to sensor failures, thus supporting stable crop production.

Keywords:Greenhouse horticulture, Temperature, Humidity, Sensing, Environmental control