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Enhancing supply chain efficiency for air transport of horticultural products by simplified heat and mass transfer modelling
(2026-08-01)
Jantapirak, Suveena
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Duret, Steven
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Laguerre, Onrawee
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Denis, Alain
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Paviet Salomon, Yvanne
Maintaining temperature and quality stability of fresh horticultural products during air transportation is challenging due to highly variable thermal environments and limited airflow inside Unit Load Device (ULD) containers. This study developed a simplified three-dimensional heat and mass transfer model to predict product temperature and moisture evolution within a ULD container under realistic operating conditions. Plaster mangoes were used to avoid the variability of the real product properties. Convective heat transfer and three-directional thermal resistances were integrated into an unsteady heat balance model while the model parameters were calibrated using Monte Carlo simulation. A complementary mass transfer model, considering the ULD container as a closed moisture domain, was implemented to estimate product mass loss. Model performance was evaluated using cooling experiments under controlled conditions and field measurements in a ULD shipment from Bangkok to Paris by air transport. Simulated air and product temperatures showed good agreement with experimental data, with RMSE values below 3.5 °C. The model successfully captured the pronounced thermal load on top-layer boxes during tarmac exposure and the faster cooling of bottom boxes through conduction with the bottom wall during flight. Predicted mass loss (1.0-1.1%) also aligned with field data (1.1-1.2%). The model provides a practical tool for assessing the effects of operational and environmental conditions on fruit quality during air transport.
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Dataset of air cargo supply chain conditions and fruit quality evolution: Case study of mango shipment from Thailand to France
(2025-08-01)
Paviet-Salomon, Y.
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Laguerre, O.
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Duret, S.
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Denis, A.
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Mawilai, P.
This study presents a detailed dataset collected during the international transport of mangoes (Mangifera indica L. cv. ‘Nam Dok Mai Si-Thong’) within a fully loaded Unit Load Device (ULD). The ULD contained 148 boxes (14 mangoes/box) and 31 boxes were instrumented by data loggers to monitor air and mango temperatures, as well as air humidity along the shipment. Measurements were recorded every 5 min throughout the 86.2 hour journey from Bangkok (Thailand) to Paris (France), it included cold storage, refrigerated transport, airport warehouse, air transport, and final delivery to the FRISE-INRAE laboratory in Paris suburban. At reception (Day 3), all boxes were stored at two temperatures (16 °C and 21 °C) over 15 days during which mango quality was assessed. Key quality attributes such as mass loss, peel color, pH, sugar content, and visual appearance were evaluated at Day 3, Day 6, Day 9, and Day 15 to highlight the impact of storage conditions on fruit quality. It is to be noticed that the same quality assessment was undertaken after harvest and before the cold storage in Thailand (Day 0). The dataset comprises raw and processed data files that include the temperature and humidity changes over time, as well as the quality evolution. These data are stored in series of txt files, with raw values and processed results i.e. min, max, average values, standard deviation and variance to facilitate future analysis. Additionally, the dataset includes series of jpeg files of mango images at different assessment days. This dataset is valuable for both practical and research purposes. For fruit exporters, it offers the insights into how different positions within a ULD can affect mango quality during a long-distance transport and implements certain measures to minimize quality degradation. For researchers, the dataset provides a base for numerical models validation, such as simplified thermal models and Computational Fluid Dynamics simulations. The international supply chain dataset is rare because of the complexity and the cost of implementation.
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Indonesian Throughflow, spatial–temporal variability, and its relationship to ENSO events in the Lombok Strait
(2025-03-01)
Lubis, Muhammad Zainuddin
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Situmorang, Edriyan
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Simanjuntak, Andrean V.H.
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Riama, Nelly F.
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Pasma, Gumilang R.
Understanding the interactions between ocean currents and climate variability is crucial for predicting future oceanic and climatic shifts in the Lombok Strait and beyond. Our study examines the Lombok Strait from 2013 to 2018, focusing on the impact of interannual and seasonal variability driven by climatic events such as the El Niño-Southern Oscillation. Our findings reveal significant fluctuations in oceanographic parameters, including temperature, salinity, and ocean currents. The lowest recorded temperature was ∼27.2 °C, and the minimum salinity was ∼32.3 psu, linked to the strong El Niño event in 2015, which altered local rainfall and evaporation patterns. Analysis of meridional and zonal velocities showed enhanced water flow, with maximum meridional velocities reaching around ∼0.04 m/s and zonal velocities peaking at ∼0.18 m/s in early 2018. Seasonal variations in sea surface height show higher values during warmer months, reflecting the influence of ENSO phenomena. The vertical distribution of salinity indicated stratification, with values ranging from ∼27.5 psu to ∼34.0 psu across different depths, corresponding to water density ranging from 22.50 σ<inf>θ</inf> to 24.0 σ<inf>θ</inf>, highlighting the interaction between Pacific and Indian Ocean waters. Water mass transport averages at 100 m and 200 m show values of −1.21 ± 0.97 Sv and −1.350 ± 1.069 Sv, with the lowest transport occurring during the summer at −1.97 Sv with a depth range of 0–100 m, suggesting robust outflow. Our findings underscore the critical role of the ITF in shaping regional oceanographic conditions and their implications for global climate dynamics.
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Non-invasive techniques with vital signs for glucose monitoring
(2025-01-01)
Mahittikorn, Pawarit
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Tangkiatphaibun, Parawee
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Thitathan, Thitisart
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Udomtanasub, Pholchanok
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Piyawattanametha, Wibool
This study is focusing on integrating finger sleeves for machine-learning with Near-infrared (NIR) spectroscopy and additional sensors techniques. It applied light emitting diodes (LEDs) at 660 nm, 880 nm, 940 nm wavelengths and photodetectors and a galvanic skin response (GSR) and a temperature sensor to read the signal from patients’ fingers. These sensors are attached to the finger sleeves to make it easy to wear for this continuous glucose monitoring. After the data was collected from the NIR spectroscopy and multiple sensors it has used in the machine learning models to predict the blood sugar level. For the machine learnings that was selected in this study are Linear regression, and Random forest model. Which the R2 result was 0.07 and -0.27 respectively.
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Techniques of Maximum Power Point Tracking by Using Perturb and Observe and Lookup Table Methodologies
(2025-01-01)
Lapkitticharoenchai, Yuttikarn
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Jangwanitlert, Anuwat
– In the typical Photovoltaic (PV) system, the Perturb and Observe (P&O) technique is the algorithm that is used for tracking the Maximum Power Point (MPP). It enables the photovoltaic (PV) panel to reach the maximum power output. However, there are two main existing problems which are the slow speed of the P&O, and an oscillation of power around MPP. The problems lead to a reduction of the power output of the PV panel. This paper presents a new hybrid methodology for a faster Maximum Power Point Tracking (MPPT) application. The proposed method consists of the Lookup Table, together with the P&O techniques. The results show that the Lookup Table employs measured values of an irradiance, a temperature, and a Duty Cycle to achieve MPPT precisely. Consequently, the Lookup Table’s tracking speed is significantly faster than P&O and the oscillation of tracking power is eliminated. Moreover, the new hybrid methodology also uses P&O to record irradiance, temperature, and Duty Cycle data into the table. Once sufficient data are collected and under defined the conditions, the system automatically select to the Lookup Table for operation.
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Evaporative cooling with a wet fabric blanket for non-refrigerated horticultural produce transport: An experimental study
(2024-12-01)
Chaomuang, Nattawut
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Laguerre, Onrawee
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Supapvanich, Suriyan
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Flick, Denis
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Duret, Steven
Due to the high cost of mechanical refrigeration, Evaporative Cooling (EC) can be an alternative technology for small farmers in developing countries, such as Thailand. This study aimed to experimentally investigate the performance of EC using a wet fabric blanket. A real-scale cargo chamber, commonly used in Thailand, was constructed, and equipped with axial fans to simulate airflow during transportation. Two pallets of test products (hollow plastic balls) were loaded into the cargo and covered with the wet blanket. During the experiment, the inlet air velocities varied from 0.8 m s−1 to 3.6 m s−1 while the constant climate conditions were maintained (29–30 °C and 70–73 %RH). The air and product temperatures and air relative humidity were measured every minute for 3 h using thermocouples and hygrometers, respectively. The proposed EC method allowed the air temperature to decrease by approximately 3–4 °C. When the inlet air velocity decreased, a lower temperature reduction was observed. Simplified heat and mass transfer models were developed to interpret the load temperature evolution from the inlet to the outlet positions at different air velocities. The comparison between the measured and calculated data revealed a maximum mean relative error of 1.2 %. The quality preservation performance was also evaluated based on lettuce mass loss. Lower mass loss was observed for the product stored inside the cargo chamber (<6 %) compared to those outside (8–10 %). This study suggests the potential use of a wet blanket as an EC cooling medium for a short-distance transport to enhance the cold chain performance in Thailand.
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Experimental study of air cargo temperature variations and its impact on mango quality
(2024-04-01)
Chaomuang, N.
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Laguerre, O.
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Denis, A.
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Paviet Salomon, Y.
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Mawilai, P.
An air cargo supply chain for fresh mango was investigated from Thailand to France. Measurements of air temperature, air relative humidity, and fruit (peel) temperature were conducted using thermo-hygrometer data loggers in cartons. In a Unit Load Device (ULD) containing 148 cartons, twenty-seven instrumented cartons were placed at different positions to observe spatial and temporal temperature variations during 12 h cruising. At the destination, mango quality attributes were assessed at different time-points during 15-day storage at 16.1 °C and 21.6 °C. Throughout the supply chain, fruit temperatures ranged from 16.6 °C to 30.5 °C. During cruising, fruit temperatures in upper cartons remained almost constant, whereas base carton temperatures continuously decreased from 26.1 °C to 18.1 °C. Because of a short cruising period in comparison to a storage duration at the destination and proper ambient temperature condition during the experiment, carton position in the ULD had no discernible impact on fruit quality during storage. Fruit stored at 16.1 °C preserved superior fruit quality compared to 21.6 °C storage. For the same storage temperature, better quality of fruits stored in Thailand demonstrated the impact of air shipment on product degradation. The measured temperature and relative humidity evolutions were used as input parameters of a mass loss evolution model. A comparison with the measured data exhibited good agreement (RMSE < 1.8 % mass loss). Considering 10 % mass loss as a critical value, this model allows an estimation of the product shelf life based on a supply chain scenario.
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Study impedance and temperature behavior of LFP battery as function of relative humidity and temperature under various conditions
(2024-01-01)
Keyoonwong, Wiwat
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Phiphuannok, Kankawi
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Janesawatpong, Kittipot
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Seeboonrueang, Kotchapon
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Amnuaysap, Nuttapum
Nowadays, lithium-ion batteries are widely employed in a lot of applications. For example, using batteries to provide energy for Electric Vehicles. In use, Batteries are charged and discharged in many cycles, which impacts battery aging. Battery aging causes capacity reduction and internal resistance increase. As is well known, the battery resistance changes with temperature and state of charge (SOC). However, no one has yet studied whether relative humidity affects the battery resistance or not. In this paper, behavior of LFP batteries as function of relative humidity and temperature under various conditions is analyzed. During the aging process, a battery impedance meter was performed at various conditions to analyze the change of the battery impedance due to relative humidity and temperatures. Additionally, the time required to charge the battery under different conditions was analyzed.
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Influence of long-distance air transport conditions on horticultural product quality: Case study of fresh mango shipment from Thailand to France
(2023-08-01)
Laguerre, O.
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Duret, S.
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Chaomuang, N.
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Denis, A.
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Derens-Bertheau, E.
Four instrumented boxes of mangoes Mangifera indica L. cv. “Nam Dok Mai” were shipped from Bangkok, Thailand, to Paris, France, without control of the boxes’ positions on the aircraft. Two boxes were shipped via a direct flight and two boxes were shipped via an indirect flight. For each box, the internal air temperature, the external air temperature and relative humidity and surface temperature of two fruits were recorded throughout the supply chain from a packing house in Thailand to a storage room in France. A maximum fruit temperature of 33 °C (during transport from an orchard to the packing house) and a minimum fruit temperature of 8 °C (in a cold room of the logistics company following arrival at the airport in France via the indirect flight) were observed. The slight temperature difference between the air and the fruit surface temperature (< 1 °C on average) for both direct and indirect flights suggests that the air was stagnant inside the box and, thus conduction was the main heat transfer mode. Models of product temperature, mass loss, and peel color changes throughout the supply chain were developed. The numerical and the experimental values were in good agreement. These models were able to predict the product mass loss and peel color evolution as a function of a supply chain scenario.
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THE INFLUENCE of NANOPARTICLES on the DIELECTRIC DISSIPATION FACTOR and LIGHTNING PROPERTIES in PALM OIL-BASED NANOFLUIDS
(2022-04-01)
Pattanadech, Norasage
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Muangpratoom, Pichai
In this study, the influence of nanoparticles when mixed with insulating palm oil is investigated in terms of tan δ or the dielectric dissipation factor and lightning properties. Three different nanofluid sample types are derived from the dispersion of zinc oxide (ZnO), titanium dioxide (TiO2) and barium titanate (BaTiO3). The nanoparticle concentrations tested were 0.01% and 0.03% while the base fluid was unmodified palm oil. Evaluation of tan δ was performed in accordance with the IEC 60247 standard via the use of the tan δ meter (model SOKEN: DAC-IM-D6) and the lightning impulse breakdown voltage were based on the IEC 60897 standard. In order to test the electrical insulation qualities of the palm oil over a range of temperatures from 35-90°C for each of the tan δ values revealed the dielectric loss tangent, and the findings lightning properties was performed at the room temperature. Significant increases of the palm oil with nanoparticles in comparison to unmodified palm oil. These results suggested that further investigation would be worthwhile to better understand the effects of the nanoparticles in palm oil upon tan δ and the lightning impulse breakdown voltage characteristics in order to make additional improvements.

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