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101.
M Hernon CP Harris M Elstein CA Russell MW Seif 《Canadian Metallurgical Quarterly》1995,10(4):960-964
In acknowledging that 'counselling is generally recognized as beneficial', the Human Fertilization and Embryology Authority (HFEA) Code of Practice requires that all infertility units provide counselling facilities to be available for patients. In this study, we intended to evaluate the support and counselling services made available by the licensed units in the UK. A questionnaire consisting of 30 questions was designed and sent to every licensed treatment unit in the UK. The data were coded on a nominal scale and, using a data entry program, loaded onto a computer. Using the Statistical Package for the Social Sciences program, a non-parametric frequency analysis was performed. Associations were examined with cross-tabulations and chi 2 analysis. A total of 62 units (61.4%) responded to the questionnaire, from both the private and National Health Service sectors. Of these, 95% have their own counsellor, most of whom (84%) practised on the premises. One-third of these counsellors had a dual role, mainly as nurses, social workers or in administration; 98.6% were trained in counselling, with only 28% having either the Certificate or Diploma in Counselling. One-third (32.2%) of centres charged for counselling, with only 13 units indicating their charges. The majority of centres (78.8%) do not actively follow-up patients after counselling and one-quarter (25.5%) did not have a specific counselling room. Over two-thirds (68.4%) of centres described their support network as adequate. The results of this survey suggest that, although the requirements of the HFEA Code of Practice are being adhered to reasonably well, overall patient uptake of counselling is low.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
102.
Message sequencing and channel assignment are two important issues that need to be addressed when scheduling variable-length messages in a wavelength division multiplexing (WDM) network. Channel assignment addresses the problem of choosing an appropriate data channel via which a message is transmitted to a node. This problem has been addressed extensively in the literature. On the other hand, message sequencing which addresses the order in which messages are sent, has rarely been addressed. In this paper, we propose a set of scheduling techniques for single-hop WDM passive star networks, which address both the sequencing aspect and the assignment aspect of the problem. In particular, we develop two priority schemes for sequencing messages in a WDM network in order to increase the overall performance of the network. We evaluate the proposed algorithms, using analytical modeling and extensive discrete event simulations, by comparing their performance with state-of-the-art scheduling algorithms that only address the assignment problem. We find that significant improvement in performance can be achieved using our scheduling algorithms where message sequencing and channel assignment are simultaneously taken into consideration. This suggests that, when scheduling messages in WDM networks, one has to consider message sequencing, as well as channel assignment. As a result, we anticipate that this research will open new directions into the problem of on-line scheduling in WDM networks 相似文献
103.
104.
Mahdi Sparham M. Hamdi R. G. Rahbari Reza Mahmoodian 《The International Journal of Advanced Manufacturing Technology》2013,67(5-8):1755-1764
The development of new lubrication methods in CNC machine carriages is a current requirement in the machining industry. Previously, lubrication systems of CNC machines were only improved via injection automation approaches. This paper focuses on the lubrication mode on the linear guideways of CNC machines. Additionally, the research investigates the effects of oil injection time and the amount of the required lubricant for accurate and precise machining. This study was also concerned with variations in environmental temperature and carriage movement conditions. Oil injection amount was determined by pump response interval (PRI), which was varied for optimization. Smart optimum quantity lubrication (SOQL) was applied to overcome unexpected changes in practical parameters during machining. The optimum oil consumption of SOQL was achieved when PRI was 15 s, resulting in a reduction of oil consumption of up to 25 %. The SOQL technique is an emerging method in lubrication technology and plays an important role in alleviating the current issues that CNC lubrication systems are faced with. 相似文献
105.
106.
Hamdi Ben Yahia Masahiro Shikano Hikari SakaebeHironori Kobayashi 《Materials Chemistry and Physics》2013
The new compounds LiNaFe1−xMnx[PO4]F (x ≤ 1/4) were synthesized by a solid state reaction route. The crystal structure of LiNaFe3/4Mn1/4[PO4]F was determined from single crystal X-ray diffraction data. LiNaFe3/4Mn1/4[PO4]F crystallizes with the Li2Ni[PO4]F-type structure, space group Pnma, a = 10.9719(13), b = 6.3528(7), c = 11.4532(13) Å, V = 798.31(16) Å3, and Z = 8. The structure consists of edge-sharing (Fe3/4Mn1/4)O4F2 octahedra forming (Fe3/4Mn1/4)FO3 chains running along the b-axis. These chains are interlinked by PO4 tetrahedra forming a three-dimensional framework with the tunnels and the cavities filled by the well-ordered sodium and lithium atoms, respectively. The manganese-doped phases show poor electrochemical behavior comparing to the iron pure phase LiNaFe[PO4]F. 相似文献
107.
108.
Shahin Heidari Saeed Seif Mohammadi Amandeep Singh Oberoi John Andrews 《International Journal of Hydrogen Energy》2018,43(12):6197-6209
The technical feasibility of a small-scale ‘proton battery’ with a carbon-based electrode is demonstrated for the first time. The proton battery is one among many potential contributors towards meeting the gargantuan demand for electrical energy storage that will arise with the global shift to zero greenhouse emission, but inherently variable, renewable energy sources. Essentially a proton battery is a reversible PEM fuel cell with an integrated solid-state electrode for storing hydrogen in atomic form, rather than as molecular gaseous hydrogen in an external cylinder. It is thus a hybrid between a hydrogen-fuel-cell and battery-based system, combining advantages of both system types. In principle a proton battery can have a roundtrip energy efficiency comparable to a lithium ion battery. The experimental results reported here show that a small proton battery (active area 5.5 cm2) with a porous activated carbon electrode made from phenolic resin and 10 wt% PTFE binder was able to store in electrolysis (charge) mode very nearly 1 wt% hydrogen, and release on discharge 0.8 wt% in fuel cell (electricity supply) mode. A significant design innovation is the use of a small volume of liquid acid within the porous electrode to conduct protons (as hydronium) to and from the nafion membrane of the reversible cell. Hydrogen gas evolution during charging of the activated carbon electrode was found to be very low until a voltage of around 1.8 V was reached. Future work is being directed towards increasing current densities during charging and discharging, multiple cycle testing, and gaining an improved understanding of the reactions between hydronium and carbon surfaces. 相似文献
109.
Fermentation time has an influence on the quality characteristics of fermented meat products. The effect of heat treatment on physicochemical, sensory and microbiological properties of sucuk was determined during fermentation and after heat application, and the properties of heat-treated sucuk samples were compared with those of traditional sucuk. Optimum fermentation period was determined for sucuk samples with desirable characteristics. Heat-treated sucuks were fermented at different fermentation intervals (0, 1, 2, 3, 4 and 5 days). Nine days of fermentation was included for traditional sucuks. All process parameters were applied under industrial conditions. Heat treatment increased the pH values, dry matter contents (protein, fat and salt), thiobarbituric acid reactive substances of sucuks while decreasing the moisture content, free fatty acidity, and all bacterial counts (total viable and lactic acid bacteria, Staphylococcus/Micrococcus and Enterobacteriaceae) (P < 0.05). Significant differences in the instrumental color properties of heat-treated and traditional sucuk were found (P < 0.05). In terms of physicochemical, sensory and microbial properties, fermentation for three or more days before heat treatment resulted in sucuk samples with better acceptability, and produced sucuk samples with quality characteristics similar to those of traditional sucuks. 相似文献
110.
Combined effect of carnosol,rosmarinic acid and thymol on the oxidative stability of soybean oil using a simplex centroid mixture design 下载免费PDF全文