Innovative travel time model for dual-shuttle automated storage/retrieval systems

In modern production and distribution systems, the automated storage/retrieval systems (AS/RS), high-storage level systems that reduce labor cost, required floor space and error rate, while increasing product availability, have been widely used since the 1950s. Due to the high-investment costs involved in the development of high-efficient and high-flexible automated storage systems, performance estimation of the systems is both practically and theoretically important. The authors suggest a new method to estimate the travel time of a recently emerging version of AS/RSs, the multi-shuttle systems. The proposal is based on an industrial standard established by the Federation Européenne de la Manutention (F.E.M.). In order to estimate travel times, the authors conduct a Monte Carlo simulation to determine coordinates of two additional representative points which are not given by F.E.M. Then they conduct a new Monte Carlo simulation to compare the results obtained by the method they proposed with those of previous methods and models developed in scientific literature based on Bozer and White formulations. Several real industrial applications demonstrate the validity of proposed method.     

A comparative evaluation of nonlinear dynamics methods for time series prediction

A key problem in time series prediction using autoregressive models is to fix the model order, namely the number of past samples required to model the time series adequately. The estimation of the model order using cross-validation may be a long process. In this paper, we investigate alternative methods to cross-validation, based on nonlinear dynamics methods, namely Grassberger–Procaccia, Kégl, Levina–Bickel and False Nearest Neighbors algorithms. The experiments have been performed in two different ways. In the first case, the model order has been used to carry out the prediction, performed by a SVM for regression on three real data time series showing that nonlinear dynamics methods have performances very close to the cross-validation ones. In the second case, we have tested the accuracy of nonlinear dynamics methods in predicting the known model order of synthetic time series. In this case, most of the methods have yielded a correct estimate and when the estimate was not correct, the value was very close to the real one.     

Scrotal hematoma due to neonatal adrenal hemorrhage: the value of ultrasonography in avoiding unnecessary surgery

Scrotal hematoma is an uncommon presentation of neonatal adrenal hemorrhage. Nine previous cases of such an association have been reported in the literature, and unnecessary surgery was carried out in five of these cases. The authors report three new cases observed during a 3-year period and stress the critical role of scrotal and abdominal ultrasonography in order to avoid unnecessary surgical exploration.     

Dream interpretation can change beliefs about the past.

Forty-six nonclinical subjects reported on their childhood experiences on two occasions, separated by 3–4 weeks. between these sessions, some subjects were exposed to a 30-min therapy simulation in which their dream material was analyzed by a clinical psychologist. He suggested to subjects that their dreams were indicative of having experienced, before the age of three, certain critical experiences (e.g., being lost in a public place or feeling abandoned by parents). Subjects previously reported that these critical events had not occurred. The brief therapy simulation led them to dramatic shifts in belief that the experiences had occurred. These results show that brief therapy-like interactions can change people's beliefs about the past, and have implications for the power of clinical intervention. Dream interpretation, commonly practiced in psychotherapy to guide patient's understanding of themselves, may have unexpected side effects if it leads to beliefs about the past that may in fact be false. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Loss of ascorbic acid during storage of Conference pears in relation to the appearance of brown heart

To investigate the causes of brown heart (BH) in Conference pears, the contents of ascorbic acid (AA) and dehydroascorbic acid (DHAA) in fruits were studied during the first period of storage. AA was studied in 1999 and 2000, DHAA in 1999 only. Pears from normal and very late harvest stored immediately or after a delay in a controlled atmosphere with 2% O₂ and low (0.7%) or high (5%) CO₂ were compared. DHAA content did not change during storage in any treatment. AA decreased in storage according to an exponential model. The rate of AA loss was different in the two years and was higher in late‐harvest fruits and in those stored in 5% CO₂. BH appeared in different treatments when AA decreased below a threshold, which was about 2 mg kg^?1 fresh weight, corresponding to 5% of the AA content at harvest. The frequency and severity of symptoms depended linearly on the time spent by fruits in low‐ascorbate conditions. Advanced maturity at harvest and storage in high CO₂ determine the appearance of BH and increase the rate of AA loss, probably through a reduction in the turnover of antioxidants. © 2002 Society of Chemical Industry     

Sex differences in social reinstatement motivation of the domestic chick (Gallus gallus) revealed by runway tests with social and nonsocial reinforcement.

Male and female chicks (Gallus gallus) were trained at 4 days old to run along a corridor to reach a goal box that contained either cagemates (social reinforcement) or food (nonsocial reinforcement). Females ran faster when social reinforcement was used, whereas males ran faster with nonsocial reinforcement. When social reinforcement was used with a V-shaped runway, in which chicks had to proceed toward the goal object in an indirect fashion, sex differences were reversed. The results may be due to stronger social reinstatement tendencies in females than in males: Higher levels of social motivation facilitate behavioral performance when the task is easy (straight runway) and inhibit it when the task is difficult (V-shaped runway). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Determination of metals in wine with atomic spectroscopy (flame-AAS, GF-AAS and ICP-AES); a review

Metals in wine occur at the mg l 1 level or less and, though not directly related to the taste of the final product, their content should be determined because excess is undesirable, and in some cases prohibited, due to potential toxicity. Lead content in wine, for example, is restricted in several states by legislation to guarantee consumer health protection. Of several methods for metal determination, techniques of atomic spectroscopy are the most sensitive and rapid. Most of the elements present in wine can be determined with these techniques, at concentrations ranging from the mg l -1 to the μg l -1 level. Here, inductively coupled plasma-atomic emission spectrometry (ICP-AES), flame atomic absorption spectrometry (flame-AAS) and graphite furnace-atomic absorption spectrometry (GF-AAS) are compared for their characteristics as employed in metal determination in wine.     

Aerodynamic and thermal investigations for the new Lyon/Turin Cross-Alpine rail link

The paper describes a system for assessing unambiguously the quality of tunnel blasting. The system can be used to compare the working practices of different operations. The economic implications of blasting accuracy are analysed on the basis of data collected in actual operations. Drilling accuracy is identified as a primary factor in reducing tunnelling costs.