Experiments about the forced-air precooling of cucumbers were carried out under different operation parameters. The results show that the relation between cooling rate and air velocity can be given by power function. The linear relationship between the initial temperature of cold air and cucumbers and the final temperature of cucumbers is gained. Temperature gradient exists in different radius ...

We studied the effect of precooling and the use of an ethylene absorbent (based on potassium permanganate) in the flower boxes, on the vase life of Dendrobium ‘Pompadour’ flowers, after simulation of air shipment (3 days at 25°C). Precooling at 10°C (85-95%RH) for 60 minutes reduced ethylene production, ACC activity, and the concentration of 1-aminocyclopropane-1-carboxylic acid (ACC) in the fl...

BACKGROUND Pre-cooling is known to enhance exercise performance in soccer players. However, little information currently exists regarding precooling effects in Iranian young soccer players. OBJECTIVES The aim of this study was to assess the effect of precooling (water immersion) on exhaustive performance in the heat ( temperature = 32 - 34°C, humidity = 50%). PATIENTS AND METHODS Sixteen yo...

Precooling studies confirm that increasing body heat is a limiting factor during exercise. However, it seems that precooling is only beneficial for endurance exercise of up to 30-40 minutes rather than intermittent or short duration exercise.

Objective—To examine the eVects of precooling skin and core temperature on a 70 second cycling power test performed in a warm and humid environment (29°C, 80% relative humidity). Methods—Thirteen male national and international level representative cyclists (mean (SD) age 24.1 (4.1) years; height 181.5 (6.2) cm; weight 75.5 (6.4) kg; maximal oxygen uptake (V~O2peak) 66.1 (7.0) ml/kg/min) were t...

OBJECTIVE To examine the effects of precooling skin and core temperature on a 70 second cycling power test performed in a warm and humid environment (29 degrees C, 80% relative humidity). METHODS Thirteen male national and international level representative cyclists (mean (SD) age 24.1 (4.1) years; height 181.5 (6.2) cm; weight 75.5 (6.4) kg; maximal oxygen uptake (VO2peak) 66.1 (7.0) ml/kg/m...

BACKGROUND Exercise increases core body temperature (Tc), which is necessary to optimise physiological processes. However, excessive increase in Tc may impair performance and places participants at risk for the development of heat-related illnesses. Cooling is an effective strategy to attenuate the increase in Tc. This meta-analysis compares the effects of cooling before (precooling) and during...

Precooling a building overnight during the summer is a low cost practice that may provide significant help in decreasing energy demand and shaving peak loads in buildings. The effectiveness of precooling depends on the weather patterns at the location, however research in this field is predominantly focused in the building thermal response alone. This paper proposes an analytical tool for asses...

We study the problem of heating, ventilation, and air conditioning (HVAC) control in a typical commercial building. We propose a model predictive control (MPC) approach which minimizes energy use while satisfying occupant comfort constraints. A sequential quadratic programming algorithm is used to efficiently solve the resulting bilinear optimization problem. This paper presents the control des...