Optimal sorting of product into fixed weight packaging

Compac Sorting Equipment make very nifty machines for sorting fruit by weight, diameter, colour, density, blemish or even shape. Compac sought solutions to two closely related problems: the boxing problem and the bagging problem. The boxing problem requires graded fruit to be assigned to outlets where boxes are filled with a specified number of fruit to a minimum weight (and a specified tolerance for underweights). The aim is to maximise the number of boxes packed. The decision must be made after all information is known, but before the fruit passes the first outlet - a few seconds total. Further, information about fruit already packed in a given box is incomplete (we don’t know exactly which fruit ended up in a box). The bagging problem requires bags to be filled to a minimum weight - no tolerance for underweights, and no constraints on the number of fruit per bag. In this case complete information is available on fruit already assigned to a bag. Again the aim is to maximise the number of bags packed

High resolution spatial variability in spring snowmelt for an Arctic shrub-tundra watershed

Arctic tundra environments are characterized by spatially heterogeneous end-of-winter snow cover because of high winds that erode, transport and deposit snow over the winter. This spatially variable end-of-winter snow cover subsequently influences the spatial and temporal variability of snowmelt and results in a patchy snowcover over the melt period. Documenting changes in both snow cover area (SCA) and snow water equivalent (SWE) during the spring melt is essential for understanding hydrological systems, but the lack of high-resolution SCA and SWE datasets that accurately capture micro-scale changes are not commonly available, and do not exist for the Canadian Arctic. This study applies high-resolution remote sensing measurements of SCA and SWE using a fixed-wing Unmanned Aerial System (UAS) to document snowcover changes over the snowmelt period for an Arctic tundra headwater catchment. Repeat measurements of SWE and SCA were obtained for four dominant land cover types (tundra, short shrub, tall shrub, and topographic drift) to provide observations of spatially distributed snowmelt patterns and basin-wide declines in SWE. High-resolution analysis of snowcover conditions over the melt reveal a strong relationship between land cover type, snow distribution, and snow ablation rates whereby shallow snowpacks found in tundra and short shrub regions feature rapid declines in SWE and SCA and became snow-free approximately 10 days earlier than deeper snowpacks. In contrast, tall shrub patches and topographic drift regions were characterized by large initial SWE values and featured a slow decline in SCA. Analysis of basin-wide declines in SCA and SWE reveal three distinct melt phases characterized by 1) low melt rates across a large area resulting in a minor change in SCA, but a very large decline in SWE with, 2) high melt rates resulting in drastic declines in both SCA and SWE, and 3) low melt rates over a small portion of the basin, resulting in little change to either SCA or SWE. The ability to capture high-resolution spatio-temporal changes to tundra snow cover furthers our understanding of the relative importance of various land cover types on the snowmelt timing and amount of runoff available to the hydrological system during the spring freshet

Key Factors Supporting Small-Scale Coastal Fisheries Management

This synthesis was designed to provide an evidence base on the success factors in small-scale coastal fisheries management in developing countries and, in turn, to assist the Rockefeller Foundation in developing its strategy for its Oceans and Fisheries Initiative. In doing so, it identifies and describes some 20 key factors believed to influence success in small-scale coastal fisheries management. The report was completed via a rapid review of key sources of knowledge from formal published literature, institutional literature, key informants and Internet searches. The focus was on key success factors in achieving a balance of social, economic and ecological benefits from the management of small-scale coastal fisheries. A summary of these success factors can also be explored via an interactive visualization that accompanies this report

FUTURES MARKET DEPTH: REVEALED VS. PERCEIVED PRICE ORDER IMBALANCES

In this paper we study futures market depth by examining the price path due to order imbalances thereby allowing us to directly gain insight in the execution costs due to a lack of market depth We propose a two dimensional market depth measure in which the price path due to order imbalances is described by an S-shape function. The proposed market depth measure is applied to transaction specific futures data from Euronext. Subsequently, we examine CBOT traders' perceptions about the price path due to order imbalances and examine the characteristics that are associated with a particular perception. The proposed market depth measure gives guidelines for improving market depth, and can be used to compare competitive futures contracts. It appears that the actual price path due to order imbalances does not match the perceived price path. Traders have various perceptions about the price path due to order imbalances. Dominant perceptions were, S-shape, linear, exponential or zigzag price paths. The differences in traders' perceptions can be traced back to different traders' characteristics among others type of primary futures contract traded, importance of information sources and trading strategy (herd vs. non-herd behavior). The observed disconnect between perceptions and revealed price path due to order imbalances have great implications for market participants who try to minimize execution costs and for the futures exchange management that tries to increase the market depth.Marketing,

Quintessence in a quandary: prior dependence in dark energy models

The archetypal theory of dark energy is quintessence: a minimally coupled scalar field with a canonical kinetic energy and potential. By studying random potentials we show that quintessence imposes a restricted set of priors on the equation of state of dark energy. Focusing on the commonly-used parametrisation, $w(a)\approx w_0+w_a(1-a)$, we show that there is a natural scale and direction in the $(w_0, w_a)$ plane that distinguishes quintessence as a general framework. We calculate the expected information gain for a given survey and show that, because of the non-trivial prior information, it is a function of more than just the figure of merit. This allows us to make a quantitative case for novel survey strategies. We show that the scale of the prior sets target observational requirements for gaining significant information. This corresponds to a figure of merit FOM$\gtrsim 200$, a requirement that future galaxy redshift surveys will meet.Comment: 5 pages, 3 figures. For the busy reader, Fig. 1 is the money plot. v2: Minor changes, matches published version. Code open source at gitorious.org/random-quintessenc

Influence of a Beaufort Sea Storm Surge on Channel Levels in the Mackenzie Delta

A storm surge in the Canadian Beaufort Sea during September 1985 resulted in a maximum water level of 1.73 m asl and a maximum surge component of 1.38 m at Tuktoyaktuk. This surge resulted in rises in channel water levels of 1.05 m in the outer delta, 0.66 m in the middle delta and 0.16 m in the upper delta, with the peak water levels at these stations lagging 4, 17, and 21 hours respectively behind the peak water level in the Beaufort Sea. This surge clearly illustrates a number of points. First, throughout the Mackenzie Delta increased water levels resulting from surges must be taken into account when calculating channel discharge from a stage-discharge relationship. Second, storm surges play an important role in the flooding of delta lakes. However, further work is required to illustrate the relative importance of flooding by the Mackenzie River versus storm surge related flooding. Third, the surge of September 1985 illustrates the potential effect of rising sea level. Although this surge cannot be used as a direct analogue for future sea level rise because the dynamics of the system are non-linear, it clearly shows that a rise in sea level would have a major impact on the water level regime of delta channels and lakes. Further work should utilize a numerical simulation model to illustrate the effect of rising sea level on water levels in the Mackenzie Delta.Key words: Mackenzie Delta, storm surge, channel water levels, climate changeUne onde de tempête dans la partie canadienne de la mer de Beaufort, qui a eu lieu en septembre 1985, a produit un niveau d'eau maximal de 1,73 m ASL et une composante de houle maximale de 1,38 m à Tuktoyaktuk. Cette houle a fait monter le niveau d'eau du chenal de 1,05 m dans la partie extérieure du delta, de 0,66 m dans la partie médiane, et de 0,16 m dans la partie supérieure, le niveau d'eau optimal à ces divers endroits étant respectivement atteint 4, 17 et 21 heures après l'avoir été dans la mer de Beaufort. Cette houle illustre clairement un certain nombre de points. Premièrement, il faut tenir compte, dans tout le delta du Mackenzie, de l'élévation du niveau d'eau due à la houle lorsqu'on calcule le débit du chenal d'après la relation hauteur-débit. Deuxièmement, les ondes de tempête jouent un rôle important dans l'inondation des lacs deltaïques. D'autres travaux sont cependant nécessaires pour illustrer l'importance relative de l'inondation due au fleuve Mackenzie par rapport à celle due aux ondes de tempête. Troisièmement, la houle de septembre 1985 illustre l'effet potentiel d'une élévation du niveau de la mer. Bien qu'on ne puisse utiliser cette onde comme représentation exacte d'une future élévation du niveau de la mer - car la dynamique du système est non linéaire -, elle montre cependant clairement qu'une élévation aurait d'importantes répercussions sur le régime du niveau d'eau dans les chenaux et lacs deltaïques. Il faudrait poursuivre les travaux en utilisant un modèle de simulation numérique pour illustrer l'effet de l'élévation du niveau de la mer sur le niveau d'eau dans le delta du Mackenzie.Mots clés: delta du Mackenzie, onde de tempête, niveaux d’eau de chenal, changement climatiqu

Warming spring air temperatures, but delayed spring streamflow in an Arctic headwater basin

This study will use the Mann–Kendall (MK) non-parametric trend test to examine timing changes in spring (early May to the end of June) streamflow records observed by the Water Survey of Canada during 1985–2011 in an Arctic headwater basin in the Western Canadian Arctic. The MK test shows a general delay in the five timing measures of springtime streamflow, which are based on the 5 percentile (Q5), 10 percentile (Q10), 50 percentile (Q50), 90 percentile (Q90), and 95 percentile (Q95) dates of spring runoff, respectively. However, much stronger trend signals were clearly noted for the high percentiles than that for the low and middle percentiles, indicating different effects of hydroclimate processes working on the timing of springtime streamflow. In contrast, the earlier snowmelt onset derived from daily mean temperatures was found over the 27-year study period. In addition, multiple relationships were correlated between these five timing measures of spring runoff and five hydroclimate indicators (total snowfall, snowmelt onset, spring temperature fluctuation, spring rainfall, and spring rainfall timing) in order to identify possible causes on the changes of springtime streamflow timing. The results indicate that the differences are due to the contradictory effects of winter–spring air temperature changes, temperature fluctuation during the melting period, and spring rainfall to spring runoff. The earlier snowmelt onset, which is attributed to the winter–spring warming, and spring temperature fluctuation that works in the opposite way, result in the minor timing changes of Q5, Q10, and Q50. The increase in spring rainfall and its delayed timing have a significant impact on the dates of Q90 and Q95. Moreover, the decreased total snow accumulation over the winter season only has a minor influence on the timing of springtime streamflow

The brain makes the fit: on the materialist hypothesis to consciousness, neuropsychology and person-organisation fit

This theory paper presents an analysis of the materialist hypothesis to consciousness and its implications for person–organization (P–O) fit. Some implications from neuropsychology are also considered. Three implications for P–O fit are discussed: (1) how it affects the underpinning theory; (2) how it changes our definition of the term; and, (3) how P–O fit is captured. The materialist hypothesis reinforces the underpinning theory, but causes a redefinition of P–O fit. It suggests that P–O fit should be defined in terms of the individual employee's unconscious physical interaction of internal features and environmental stimuli. The review also suggests that researchers need to consider using data gathering techniques that capture unconscious dimensions of P–O fit

Mapping organizational members' sense of fit

Despite its importance in the organizational behavior literature, person–organization (P–O) fit remains an elusive construct. One reason for this is the lack of research about organizational members’ own sense of their P–O fit. In this paper we report an empirical study that explored organizational members’ own sense of fit using storytelling and causal mapping techniques. The results suggest that organizational members categorize their perceptions of their fit into five discrete domains (job, people, employment, values, and extrawork) comprising thirteen subdomains: nature of work, profession or vocation, skills and knowledge, emotions, relationships with colleagues, relationship with line manager, physical environment, conditions of employment, opportunities for growth and development, organizational values, mission, family and personal life. Reviews of respondents’ causal maps and interview transcripts gave some insight into the consequences of organizational members’ perceptions of fit and provided further insights into the nature of fit. These insights included the fragility of fit, how the degree of seniority changed the emphasis in organizational members’ fit, and the role and nature of trigger events that change people’s sense of fit from good fit to misfit

Paramedic and physician perspectives on the potential use of remotely supported prehospital ultrasound

Peer reviewedPublisher PD