Possibility Of Rolling Research Articles

USE OF ADDITIONAL ASSESSMENT CRITERION FOR TRAFFIC SAFETY AGAINST RAILWAY WHEEL DERAILMENT FOR FORENSIC RAILWAY TRANSPORT EXAMINATION

A number of methods have been developed to determine the possibility of a wheelset derailment from track, which to some extent take into account specifics of their interaction. However, methods used in the calculation are different between themselves. The problem is complicated by the lack of sufficient experimental data which would allow to verify the adequacy of models used for calculations. Authors conducted research of an influence of an additional assessment criterion for traffic safety. According to this criterion the railway wheel derailment of a rolling stock was analyzed by actually raising the wheel flange to the railhead. It is noted that increase of the radius of wheels taken into account while calculating indicated criterion depends on transverse displacement of the wheelset, horizontal unevenness, numerical value of the wheel taper profile at the contact point with a rail, and the nominal gaps between the wheel flange and the inner edge of the railhead. On the basis of performed researches, it was concluded that use of an additional criterion, according to which the stability of the wheel from the derailment of a rolling stock is analyzed by actually raising the wheel flange on a railhead, allows to track the time when it is necessary to check the possibility of rolling the wheel on railhead. However, obtaining a negative clearance between the wheel flange and the railhead does not indicate that the wheel is rolling on the railhead. The indicated feature will allow to explore the development of a railway accident mechanism, to define more precisely its proximate technical cause and the sequence of intermediate technical reasons which have led to it.

Modified butter knife as a good transporter of epidermal graft

Blister transport is an epidermal graft procedure, and it can result in failure as a result of various factors, including tearing or flipping of the epidermal graft.1Albert S. Shenoi S.D. Acetate sheets in the transfer of epidermal grafts in vitiligo.J Am Acad Dermatol. 2001; 44: 719-720Abstract Full Text Full Text PDF PubMed Scopus (6) Google Scholar Therefore, researchers have proposed various techniques to address such challenges.2Laxmisha C. Thappa D.M. JAAD Online: Surgical pearl: gloved finger as a transport platform for epidermal graft of suction blister.J Am Acad Dermatol. 2007; 57: S118-S119Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar In this letter, we present an epidermal graft technique that uses a modified butter knife to overcome these transport problems. We manipulated the tip of an ordinary butter knife with the tip sloping down gently toward its end (Fig 1, A). To use this modified butter knife, we cut the suction cup-induced blister roof, hold the margin of the blister, and then place it on the butter knife with the dermal side facing down. The next step involves straightening the graft evenly to its full size on the modified butter knife and fixing a part of the graft margin on a certain point of the recipient site using forceps (Fig 1, B). Finally, the butter knife is moved backwards, and the graft slides gently and settles down at the recipient site, just like a flat sheet. This epidermal graft procedure using a modified butter knife results in a good cosmetic outcome (Fig 2).Fig 2Successful treatment of the epidermal graft in vitiligo using the modified butter knife.View Large Image Figure ViewerDownload Hi-res image Download (PPT) The epidermal graft can ‘slide’ in its spread form from the tip of the modified butter knife, and thus it has less possibility of rolling up, flipping, or clinging. In conclusion, the modified butter knife can be a useful tool to easily and accurately transport and settle down an epidermal graft in the recipient site.

Flexible dye-sensitized solar cells based on Ti/TiO2 nanotubes photoanode and Pt-free and TCO-free counter electrode system

Flexible dye-sensitized solar cells (DSSCs) are getting more attention compared to standard glass covered DSSCs due to their unique commercial applications (e.g. tents or sail surfaces) and the possibility of rolling up into a small, portable device. In this work, titania nanotubes (TiO2 NT) modified with titania nanoparticles (TiO2 NP) were photoelectrochemically characterized as an anode for flexible dye-sensitized solar cells. The morphology of the prepared electrode materials was inspected using scanning electron microscopy. Electrochemical activity of titania in contact with anaqueous electrolyte containing iodine species was investigated using cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperometry (CA). The anode with deposited TiO2 NP exhibits enhanced efficiency of photocurrent generation in comparison to pure titania NT. The new type of comb-shaped Ti electrode with poly(3,4-ethylenedioxythiophene):poly(2-styrenesulphonate) (pEDOT:PSS) layer deposited onto the PET foil substrate was proposed as a counter electrode and compared with a conventional Pt catalytic layer as well as with a typical Pt/FTO counter electrode. Overall photoconversion efficiency of pEDOT-based counter-electrode DSSC reached 0.61% and was almost 40% higher than for counter electrode with Pt.

Analysis of rolling with slip of flexible rotor inside stator

The interaction of a rotor with a stator without separation is considered during their plane-parallel motion and under assumption of constant rotor speed. In contrast to known papers devoted to the problem of the possibility of rolling in the rotor system, it is shown that the retrograde precession frequency is always lower than the inherent one, which corresponds to a zero-clearance flexible–mobile stator system.

Government policy and wireless city networks: A comparative analysis of motivations, goals, services and their relation to network structure

Wireless City Networks are a recent, but growing phenomenon. In the United States hundreds of cities are looking into the possibility of rolling out Wi-Fi or WiMax based networks over substantial parts of the city. The underlying rationale is that wireless city networks are cheap and flexible alternatives for fixed broadband networks. Cities more and more see broadband Internet access as a necessary and therefore public utility to be provided to their communities at affordable prices or even free of charge. The deployment of wireless city networks is however more than just infrastructure provision. Initiatives are linked to broader city policies related to digital divide, city renewal, stimulation of innovation, stimulation of tourism, strengthening the economic fabric of the city, etc . In this article we will argue that explicit and implicit goals are directly linked to the coverage and topology of networks, the technology used, price and service modalities, etc. Furthermore we will argue that the differences in context between the US and Europe explain the different infrastructural trajectories taken. Overall and on the basis of empirical findings we caution for the overoptimistic view that Wi-Fi-based wireless city networks are an equal alternative for providing broadband access. There are both financial and technological uncertainties, which could have a serious impact on the performance of these initiatives.

Examination of Slab Temperature Change, Rolling Power and Rolling Capacity in a Hot Strip Mill with Mill Arrangement Equivalent to Semi Continuous Type

A mathematical model is proposed for the mill arrangement equivalent to semi continuous type in a hot strip mill. The rolling schedule is arranged so that a slab is rolled from 230mm into 60mm in bar thickness by 3 passes roughing with only one reverse mill and 60mm into 1.2mm, 2.0mm, and 2.5mm in final thickness by 7 passes finishing. The possibility of rolling in this case is analytically examined in due consideration of slab weight, temperature change, rolling power, rolling capacity, and rolling speed. As a result, the rolling of the comparably heavy slab with 30t/m in unit weight is enabled, and the temperature condition is sufficiently fulfilled. The length of the rolling mill line can be geometrically shortened very much in comparison with the case of other type hot strip mill.

半連続式と同じミル配列の熱間圧延設備におけるスラブの温度変化, 圧延動力および圧延能力の検討

A mathematical model is proposed for the mill arrangement equivalent to semi continuous type in a hot strip mill. The rolling schedule is arranged so that a slab is rolled from 230mm into 60mm in bar thickness by 3 passes roughing with only one reverse mill and 60mm into 1.2mm, 2.0mm, and 2.5mm in final thickness by 7 passes finishing. The possibility of rolling in this case is analytically examined in due consideration of slab weight, temperature change, rolling power, rolling capacity, and rolling speed. As a result, the rolling of the comparably heavy slab with 30t/m in unit weight is enabled, and the temperature condition is sufficiently fulfilled. The length of the rolling mill line can be geometrically shortened very much in comparison with the case of other type hot strip mill.