Multi-objective shop floor scheduling using monitored energy data

Modern factories will become more and more directly connected to intermittent energy sources like solar systems or wind turbines as part of a smart grid or a self-sufficient supply. However, solar systems or wind turbines are not able to provide a continuous energy supply over a certain time period. In order to enable an effective use of these intermittent energy sources without using temporary energy storages, it is necessary to rapidly and flexibly adapt the energy demand of the factory to the constantly changing requirements of the energy supply. The adaption of the energy demand to the intermittent supply results in different energy-related objectives for the production system of the factory, such as reducing energy consumption, avoiding power peaks, or achieving a power use within the available power supply. Shop Floor Scheduling can help to pursue these objectives within the production system. For this purpose, a solution methodology based on a meta-heuristic will be described for Flexible Job Shop Scheduling taking into account different energy- as well as productivity-related objectives

A comparative study on wear and corrosion behaviour of tungsten carbide-nickel and tungsten carbide-cobalt high velocity oxy-fuel (HVOF) for carbon steel blade

Nowadays, the demand of high wear and corrosion resistance of the components in various industry is increasing from time to time. Therefore, high velocity oxy-fuel (HVOF) thermal spray was introduced to protect machine components from wear and corrosion, to restore worn components and to improve the durability of the components. HVOF is one of the process of depositing a material layer over a base metal or substrate with characteristics of high flame velocity and moderate temperature. The main purpose of this present study is to characterize the structure of the tungsten carbide 10 wt.% nickel (WC-10Ni) and tungsten carbide 12 wt.% w cobalt (WC-12Co) coating deposited by means of HVOF thermal spray onto a continuous digester (CD) blade that made up from carbon steel. The morphology and chemical composition of the coating were characterized by scanning electron microscope (SEM), electron dispersive spectrometer (EDS), and x-ray diffraction (XRD). The hardness test was carried out by using Vickers micro-hardness tester with load of 490.3 mN (0.05 HV). The wear and corrosion behavior and mechanism for both coatings was compared. Three body wear test was carried out in term of weight loss and electrochemical test was performed in acidic media (mixture of sulfuric acid, H2SO4 and ilmenite) to obtain the corrosion rate of the coating. From the result, it shows that WC-12Co coating has finer grain size that is around 2.3 μm. WC-12Co has higher wear resistance due to high volume friction, low mean free path, high hardness and lower porosity distribution compared to WC-10Ni. Besides, the formation of secondary phase, W2C also affected the hardness of both coating, where this phase is harder than WC phase. For corrosion test, WC-12Co shows good corrosion resistance with small differences of corrison rate with WC-10Ni, that is only 0.7016 mm/y. As a conclusion, WC-12Co HVOF coating shows high potential on replacement of CD blade

Emergency department contact prior to suicide in mental health patients

ObjectivesTo describe attendance at emergency departments (EDs) in the year prior to suicide for a sample of mental health patients. To examine the characteristics of those who attended (particularly those who attended frequently) prior to suicide.DesignCase review of ED records for 286 individuals who died within 12 months of mental health contact in North West England (2003-2005).MethodCases identified through the National Confidential Inquiry into Suicide were checked against regional EDs to establish attendance in the year prior to death. Records were examined to establish the number of attendances, reason for the final, non-fatal attendance, treatment offered and outcome.ResultsOne hundred and twenty-four (43%) individuals had attended the ED at least once in the year prior to their death, and of these, 35 (28%) had attended the ED on more than three occasions. These frequent attenders died by suicide significantly sooner after their final, non-fatal attendance than other attenders. A clinical history of alcohol misuse was also associated with early death following ED attendance.ConclusionsOver 40% of our clinical sample attended an ED in the year prior to death, and some individuals attended particularly frequently. EDs may therefore represent an important additional setting for suicide prevention in mental health patients. The majority of attendances prior to suicide were for self-harm or to request psychiatric help. Clinicians should be alert to the risk associated with such presentations and to the possible association between frequent attendance and suicide

State enrolment and energy-carbon transitions: syndromic experimentation and atomisation in England

This article analyses how national governments seek to enrol different subjects and objects in energy-carbon restructuring. It takes analysis beyond consideration of particular subjectivities and governmentalities to consider an expanded range of objects and subjects of governing at a distance. Developing an analytical model of ‘modes of enrolment’ focusing on power modalities, forms of policy integration and policy targets, the article explores five broad modes of enrolment employed in England. The article shows how policy across all modes of enrolment in England has increasingly tended towards disordered, syndromic experimentation and government by-project rather than any systematic programme of government

Identification of Radiopure Titanium for the LZ Dark Matter Experiment and Future Rare Event Searches

The LUX-ZEPLIN (LZ) experiment will search for dark matter particle interactions with a detector containing a total of 10 tonnes of liquid xenon within a double-vessel cryostat. The large mass and proximity of the cryostat to the active detector volume demand the use of material with extremely low intrinsic radioactivity. We report on the radioassay campaign conducted to identify suitable metals, the determination of factors limiting radiopure production, and the selection of titanium for construction of the LZ cryostat and other detector components. This titanium has been measured with activities of $^{238}$U$_{e}$~$<$1.6~mBq/kg, $^{238}$U$_{l}$~$<$0.09~mBq/kg, $^{232}$Th$_{e}$~$=0.28\pm 0.03$~mBq/kg, $^{232}$Th$_{l}$~$=0.25\pm 0.02$~mBq/kg, $^{40}$K~$<$0.54~mBq/kg, and $^{60}$Co~$<$0.02~mBq/kg (68\% CL). Such low intrinsic activities, which are some of the lowest ever reported for titanium, enable its use for future dark matter and other rare event searches. Monte Carlo simulations have been performed to assess the expected background contribution from the LZ cryostat with this radioactivity. In 1,000 days of WIMP search exposure of a 5.6-tonne fiducial mass, the cryostat will contribute only a mean background of $0.160\pm0.001$(stat)$\pm0.030$(sys) counts.Comment: 13 pages, 3 figures, accepted for publication in Astroparticle Physic

Painting the Nation:Examining the Intersection Between Politics and the Visual Arts Market in Emerging Economies

Politics and art have throughout history, intersected in diverse and complex ways. Ideologies and political systems have used the arts to create a certain image and, depending on the form of government this has varied from clear-cut state propaganda, to patronage, to more indirect arms-length funding procedures. Therefore, artists working within the macro-level socio-political context cannot help but be influenced, inspired and sometimes restricted by these policies and political influences. This article examines the contemporary art markets of two emerging, Socialist economies to investigate the relationship between state pol-itics and the contemporary visual arts market. We argue that the respective governments and art worlds are trying to construct a brand narrative for their nations, but that these discourses are often at cross-purposes. In doing so, we illustrate that it is impos-sible to separate a consideration of the artwork from the macro-level context in which it is produced, distributed, and consumed

Multi-Objective Optimization with an Adaptive Resonance Theory-Based Estimation of Distribution Algorithm: A Comparative Study

Proceedings of: 5th International Conference, LION 5, Rome, Italy, January 17-21, 2011.The introduction of learning to the search mechanisms of optimization algorithms has been nominated as one of the viable approaches when dealing with complex optimization problems, in particular with multi-objective ones. One of the forms of carrying out this hybridization process is by using multi-objective optimization estimation of distribution algorithms (MOEDAs). However, it has been pointed out that current MOEDAs have a intrinsic shortcoming in their model-building algorithms that hamper their performance. In this work we argue that error-based learning, the class of learning most commonly used in MOEDAs is responsible for current MOEDA underachievement. We present adaptive resonance theory (ART) as a suitable learning paradigm alternative and present a novel algorithm called multi-objective ART-based EDA (MARTEDA) that uses a Gaussian ART neural network for model-building and an hypervolume-based selector as described for the HypE algorithm. In order to assert the improvement obtained by combining two cutting-edge approaches to optimization an extensive set of experiments are carried out. These experiments also test the scalability of MARTEDA as the number of objective functions increases.This work was supported by projects CICYT TIN2008-06742-C02-02/TSI, CICYT TEC2008-06732-C02-02/TEC, CAM CONTEXTS (S2009/TIC-1485) and DPS2008-07029-C02-02.Publicad