179,100 research outputs found
A new approach to automatically producing schedules for cane railways
No full textThe scheduling of locomotive movements on cane railways has proven to be a very complex task. Various optimisation methods have been used over the years to try and produce an optimised schedule that eliminates or minimises bin supply delays to harvesters and the factory, while minimising the number of locomotives, locomotive shifts and cane bins, and also the cane age. \ud
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This paper reports on a new attempt to develop an automatic scheduler using a mathematical model solved using mixed integer programming and constraint programming approaches and blocking parallel job shop scheduling fundamentals. The model solution has been explored using conventional constraint programming search techniques and found to produce a reasonable schedule for small-scale problems with up to nine harvesters. While more effort is required to complete the development of the full model with metaheuristic search techniques, the work completed to date gives confidence that the metaheuristic techniques will provide near optimal solutions in reasonable time. \u
Phenolics in sugar cane juice : potential degradation by hydrogen peroxide and Fenton's reagent
No full textThe presence of colour in raw sugar plays a key role in the marketing strategy of the Australian raw sugar industry. Some sugars are relatively difficult to decolourise during refining and develop colour during storage. A new approach that might result in efficient and cost-effective colour removal during the sugar manufacturing process is the use of an advanced oxidation process (AOP), known as Fenton oxidation, that is, catalytic production of hydroxyl radicals from the decomposition of hydrogen peroxide using ferrous iron. As a first step towards developing this technology, this study determined the composition of colour precursors present in the juice of cane harvested by three different methods. The methods were harvesting cane after burning, harvesting the whole crop with half of the trash extracted and harvesting the whole crop with no trash extracted. The study also investigated the degradation at pH 3, 4 and 5 of a phenolic compound, caffeic acid (3,4–dihydroxycinnamic acid), which is present in sugar cane juice, using both hydrogen peroxide and Fenton’s reagent. The results show that juice expressed from whole crop cane has significantly higher colour than juices expressed from burnt cane. However, the concentrations of phenolic acids were lower in the juices expressed from whole crop cane. The main phenolic acids present in these juices were p-coumaric, vanillic, 2,3–dihydroxybenzoic, gallic and 3,4–dihydroxybenzoic acids. The degradation of caffeic acid significantly improved using Fenton’s reagent in comparison to hydrogen peroxide alone. The Fenton oxidation was optimum at pH 5 when up to ~86 % of caffeic acid degraded within 5 min
Developing schedules for mixed rail and road cane transport systems
No full textThis paper addresses the problem of scheduling a cane transport system involving both rail transport and road transport, where the road transport operates from several sidings in the rail network. \ud
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An iterative approach for scheduling the rail transport system has been developed using existing rail transport scheduling tools. The assumption that harvesters serviced by road transport are effectively operating from the rail siding from which their bins are supplied seems a reasonable starting point for the analysis. There is a need to manually modify the schedule to take into account the road transport schedule to ensure that full bins are not collected before the road transport system delivers them back to the rail siding
Addressing factory needs in cane variety selection
No full textCane fibre content has increased over the past ten years. Some of that increase can be attributed to new varieties selected for release. \ud
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This paper reviews the existing methods for quantifying the fibre characteristics of a variety, including fibre content and fibre quality measurements – shear strength, impact resistance and short fibre content. The variety selection process is presented and it is reported that fibre content has zero weighting in the current selection index.\ud
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An updated variety selection approach is proposed, potentially replacing the existing selection process relating to fibre. This alternative approach involves the use of a more complex mill area level model that accounts for harvesting, transport and processing equipment, taking into account capacity, efficiency and operational impacts, along with the end use for the bagasse. The approach will ultimately determine a net economic value for the variety. The methodology lends itself to a determination of the fibre properties that have a significant impact on the economic value so that variety tests can better target the critical properties.\ud
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A low-pressure compression test is proposed as a good test to provide an assessment of the impact of a variety on milling capacity. NIR methodology is proposed as a technology to lead to a more rapid assessment of fibre properties, and hence the opportunity to more comprehensively test for fibre impacts at an earlier stage of variety development
The water relations and irrigation requirements of sugar cane (Saccharum officinarum): a review.
No full textThe results of research on the water relations and irrigation needs of sugar
cane are collated and summarized in an attempt to link fundamental studies on
crop physiology to irrigation practices. Background information on the centres
of production of sugar cane is followed by reviews of (1) crop development,
including roots; (2) plant water relations; (3) crop water requirements; (4)
water productivity; (5) irrigation systems and (6) irrigation scheduling. The
majority of the recent research published in the international literature has
been conducted in Australia and southern Africa. Leaf/stem extension is a more
sensitive indicator of the onset of water stress than stomatal conductance or
photosynthesis. Possible mechanisms by which cultivars differ in their responses
to drought have been described. Roots extend in depth at rates of 5-18 mm d-
1 reaching maximum depths of > 4 m in ca. 300 d providing there are no physical
restrictions. The Penman-Monteith equation and the USWB Class A pan both give
good estimates of reference crop evapotranspiration (ETo). The corresponding
values for the crop coefficient (Kc) are 0.4 (initial stage), 1.25 (peak season)
and 0.75 (drying off phase). On an annual basis, the total water-use (ETc) is in
the range 1100-1800 mm, with peak daily rates of 6-15 mm d-1. There is a linear
relationship between cane/sucrose yields and actual evapotranspiration (ETc)
over the season, with slopes of about 100 (cane) and 13 (sugar) kg (ha mm)-1
(but variable). Water stress during tillering need not result in a loss in yield
because of compensatory growth on re-watering. Water can be withheld prior to
harvest for periods of time up to the equivalent of twice the depth of available
water in the root zone. As alternatives to traditional furrow irrigation, drag-
line sprinklers and centre pivots have several advantages, such as allowing the
application of small quantities of water at frequent intervals. Drip irrigation
should only be contemplated when there are well-organized management systems in
place. Methods for scheduling irrigation are summarized and the reasons for
their limited uptake considered. In conclusion, the ‘drivers for change',
including the need for improved environmental protection, influencing technology
choice if irrigated sugar cane production is to be sustainable are summariz
IMPACT OF REDUCING THE PRE-HARVESTBURNING OF SUGAR-CANE AREA ON RESPIRATORY HEALTH IN BRAZIL
No full textColonos, central factories, and renegotiation:. A Fixed Effects Analysis of the Adoption of New Technologies in the Cuban Sugar Industry, 1899-1929.
No full textThis paper focuses on the relationship between technical and institutional changes in Cuba a leader in the use of continuousprocess technologies being applied to cane sugar manufacture in the first three decades of the twentieth century. Using a fixed effects model of the sugar manufacturer's decision to invest in new technologies, we show that a change in institutional factors had an impact on the adoption of the new technologies. The results show that differences in cane contracting arrangements affected the ease with which mills adopted new technologies. These differences were based on historical factors in the evolution of the cane farming institution in Cuba that affected whether the cane lands were the property of the farmer or the mill. This distinction created differences in the cane farmers' bargaining positions in the renegotiation of contracts with the mill, and it resulted in variation in the long-run costs of procuring cane at different mills.Economic History; Institutional Economics; Vertical integration; Economics of technology;
A Fixed Effects Analysis of the Adoption of New Technologies in the Cuban Sugar Industry, 1899-1929
No full textThis paper focuses on the relationship between technical and
institutional changes in Cuba a leader in the use of continuousprocess
technologies being applied to cane sugar manufacture in
the first three decades of the twentieth century. Using a fixed
effects model of the sugar manufacturer's decision to invest in
new technologies, we show that a change in institutional factors
had an impact on the adoption of the new technologies. The
results show that differences in cane contracting arrangements
affected the ease with which mills adopted new technologies.
These differences were based on historical factors in the
evolution of the cane farming institution in Cuba that affected
whether the cane lands were the property of the farmer or the
mill. This distinction created differences in the cane farmers'
bargaining positions in the renegotiation of contracts with the
mill, and it resulted in variation in the long-run costs of
procuring cane at different mills
Caratteristiche dell'emogramma nel Cane da Montagna dei Pirenei
No full textSono stati raccolti i risultati di 150 emogrammi (CBC) di Cani da Montagna dei Pirenei eseguiti presso il Laboratorio di Biochimica ed Ematologia Clinica Veterinaria, Dipartimento di Clinica Veterinaria dell’Università di Pisa. Da questi sono stati selezionati 133 emogrammi appartenenti a soggetti clinicamente sani. Sono stati presi in esame 12 parametri ematologici: conta eritrocitaria (RBC), emoglobina (HGB), ematocrito (HCT), concentrazione emoglobinica corpuscolare media (MCHC), volume corpuscolare medio (MCV), ampiezza di distribuzione eritrocitaria (RDW), piastrine (PLT), conta leucocitaria (WBC), valori assoluti di neutrofili, eosinofili, linfociti e monociti con l’obiettivo di individuare caratteristiche proprie di questa razza ed eventuali variazioni dei parametri ematologici rispetto agli intervalli di riferimento per la specie canina in uso presso il suddetto laboratorio. Il CBC è stato effettuato su campioni di sangue addizionati con K3-EDTA, tramite un contaglobuli a impedenza elettrica; la formula leucocitaria e la valutazione morfologica degli eritrociti sono state realizzate attraverso l’osservazione al microscopio dello striscio ematico colorato con metodica Diff-Quik. Nel 50% degli strisci ematici sono state osservate alterazioni della morfologia eritrocitaria con maggior frequenza per poichilocitosi, anisocitosi e policromasia; tra le alterazioni della forma sono risultati di più frequente riscontro echinociti e acantociti, seguiti da altri tipi di poichilociti. I dati ottenuti dagli emogrammi hanno evidenziato una differenza significativa in base all’età per i parametri RBC, HGB, RDW, WBC e una differenza significativa in base al sesso per MCV e PLT. Gli intervalli di riferimento sono stati convalidati per 9 parametri ematologici (RBC, HGB, MCHC, RDW, PLT, WBC, valori assoluti di neutrofili, linfociti e monociti), mentre sono stati variati per gli altri 3 (HCT, MCV ed eosinofili), con la creazione di nuovi intervalli di riferimento razza-specifici per il Cane da Montagna dei Pirenei. La futura elaborazione di intervalli di riferimento razza-specifici potrebbe rendersi utile poiché costituisce un ulteriore criterio per la corretta interpretazione clinica dei dati di laboratorio nella specie canina
Influence of a walking aid on temporal and spatial parameters of gait in healthy adults
No full textThis is the post-print version of the final paper published in PM&R. The published article is available from the link below. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. Copyright @ 2014 Elsevier B.V.Objective - To determine the effect of using a walking aid on temporal and spatial parameters of gait when used for balance versus support on the dominant and nondominant hand side.
Design - Repeated measures observational study design.
Setting - University gymnasium.
Participants - Twenty-seven healthy male and female adults of mean ± standard deviation age 44.74 ± 10.00 years.
Methods - Five walking conditions (C) were completed by all participants on the GAITRite pressure mat. Normal walking (C1), walking with a cane in the dominant hand (C2) and nondominant hand (C3) as if using for balance, walking with a cane in the dominant hand (C4) and nondominant hand (C5) while allowing approximately 10% of the body weight through the cane.
Main Outcome Measurements - Temporal measurements (swing time, stance time, single limb support time, double limb support time) as percentage of a gait cycle and the base of support for the left and the right foot for all 5 walking conditions.
Results - A significant difference (P < .001) was observed between C1, C2, and C3 in percentage swing time and percentage stance time of the ipsilateral side, and in percentage single limb support time of the contralateral side. The double limb support time was significantly different (P ≤ .04) for both ipsilateral and contralateral sides. Comparisons among C1, C4, and C5 demonstrated significance (P < .001) for all variables. Post hoc analysis showed significance between C1 and C4, and C1 and C5 for all variables except percentage stance time of the ipsilateral side and percentage single limb support of the contralateral side.
Conclusions - In healthy adults, use of a cane for balance modifies swing and stance parameters of the ipsilateral side and does not affect the base of support formed by the feet. When used for support, the cane alters the swing and stance parameters, and also the base of support formed by the feet
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