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In definition of the ground response curve for a tunnel, convergences of side wall, roof and floor may be different, because of the weight of the failed or plastic rock mass. In this paper, an anal...

The aim of this paper is learning directed acyclic graph (DAG) by determination of candidate causes for each discrete variable. Based on the fact that the candidate causes of a variable must be a s...

Hurdle technology combining mild acidification (4.6 < pH < 5.0) and reduced thermal treatment could be a potential preservation technique for the production of high-quality processed canned vegetables once it has been microbiologically validated. Freshly harvested green beans were acidified in pre-prepared brine using one of three acidulants (lactic acid [LA], glucono-delta-lactone [GDL], or fermented dextrose containing organic acids), hermetically sealed in cans, and thermally processed in a pilot-scale water-immersion retort. Eight levels of acidulant concentration (0.01–19.5 g/kg) and five levels of desired lethality (0.01–2.74 min) were applied through uniform shell experimental design (Doehlert network method). The color and texture properties of blanched green beans (control samples) and thermally processed green beans with and without prior acidification were evaluated. Statistical analysis showed that acid concentration had a significant effect on color characteristics, and that lethality had a s...

When an opening is excavated below groundwater table, the groundwater flows into the excavated zone and seepage forces apply to the rock mass surrounding the opening. Such seepage forces significantly affect the elasto-plastic responses of the rock mass based on effective stress law. In this regard, it is recognised that the failure criterion of a rock mass is a function of Terzaghi’s effective stress, while its elastic deformations are a function of Biot’s effective stress. Based on this generalised effective stress law, seepage forces arising from the groundwater flow into a cylindrical opening are estimated quantitatively, in the present study. An elastic–brittle–plastic analysis of deep circular openings in an infinite Hoek–Brown medium with consideration of the seepage forces under steady-state flow and the generalised effective stress law is derived. The proposed solution can be effectively used for the actual design of underwater openings below deep groundwater table. It is shown that, in openings ...

An analytical–numerical solution is proposed in this paper for calculating the mechanical and hydraulic characteristics of underwater tunnels, excavated in an elasto-plastic strain-softening and Hoek–Brown rock material considering strain-dependent permeability. The problem is considered with axial-symmetry condition and thus, the initial stress state is assumed to be hydrostatic. Hydraulic and mechanical differential equations governing the plastic and the elastic rock mass around the tunnel are derived. As the derived equations do not have closed-form solutions, a computer program has been prepared, in order to solve the corresponding equations numerically and to examine the analysis. The results obtained are compared with the results obtained using a commercial finite difference code for investigating the effects of utilised simplifying assumptions. The proposed approach is also used to analyse the response of tunnels under different hydro-mechanical conditions. The results show that the proposed solut...

In this article, utilizing a scale mixture of skew-normal distribution in which mixing random variable is assumed to follow a mixture model with varying weights for each observation, we introduce a generalization of skew-normal linear regression model with the aim to provide resistant results. This model, which also includes the skew-slash distribution in a particular case, allows us to accommodate and detect outlying observations under the skew-normal linear regression model. Inferences about the model are carried out through the empirical Bayes approach. The conditions for propriety of the posterior and for existence of posterior moments are given under the standard noninformative priors for regression and scale parameters as well as proper prior for skewness parameter. Then, for Bayesian inference, a Markov chain Monte Carlo method is described. Since posterior results depend on the prior hyperparameters, we estimate them adopting the empirical Bayes method as well as using a Monte Carlo EM algorithm. ...

Blueberries and cranberries were dried using a hybrid technology consisting of pretreatment, osmotic dehydration, and convective drying. The performance of this hybrid technology was evaluated in terms of quality attributes such as color, taste, rehydration ratio, water activity, as well as sugar and anthocyanins content. Of thirteen different pretreatment methods tested for cranberries, cutting the berries in halves was the simplest and the best one. No pretreatment was needed for blueberries. Osmotic dehydration was performed in batch and continuous modes using sugar solution of 67.5–70°Brix. Convective drying was then carried out in a fluidized bed, a pulsed fluidized bed, or a vibrated fluidized bed. Quality profiles for both berries were determined after each step of such a hybrid technology and compared with quality of berries dried in the vibrated fluidized bed and freeze dryer. Recommendations for full-scale processing are given.

The objective of this study was to evaluate the osmotic drying kinetics of cylindrical slices of apples as influenced by particle size at different concentrations of sucrose solutions and different temperatures. Osmotic drying was carried out, with cut apple cylinders of three different sizes (12, 17 and 20mm diameter), all with a length to diameter ratio of 1:1, in a well agitated large tank containing the osmotic solution at the desired temperature. The solution to fruit volume ratio was kept greater than 60. A central composite rotatable design (CCRD) was used with dive levels of sucrose concentrations (34–63°Brix) and five temperatures (34–66°C). Kinetic parameters included weight loss, moisture loss, solids gain, rates of moisture loss and solids gain generally increased with increasing treatment time, temperature and concentration of osmotic solution, and decreased with an increase in sample size. The parameter “osmotic drying time to achieve a given moisture loss” obviously showed the opposite. Com...