Optimal Methodology for Synchronized Scheduling of Parallel Station Assembly with Air Transportation

We present an optimal methodology for synchronized scheduling of production assembly with air transportation to achieve accurate delivery with minimized cost in consumer electronics supply chain (CESC). This problem was motivated by a major PC manufacturer in consumer electronics industry, where it is required to schedule the delivery requirements to meet the customer needs in different parts of South East Asia. The overall problem is decomposed into two sub-problems which consist of an air transportation allocation problem and an assembly scheduling problem. The air transportation allocation problem is formulated as a Linear Programming Problem with earliness tardiness penalties for job orders. For the assembly scheduling problem, it is basically required to sequence the job orders on the assembly stations to minimize their waiting times before they are shipped by flights to their destinations. Hence the second sub-problem is modelled as a scheduling problem with earliness penalties. The earliness penalties are assumed to be independent of the job orders.

Bubble Behavior in a Taylor Vortex

We present an experimental study on the behavior of bubbles captured in a Taylor vortex. The gap between a rotating inner cylinder and a stationary outer cylinder is filled with a Newtonian mineral oil. Beyond a critical rotation speed (ω[subscript c]), Taylor vortices appear in this system. Small air bubbles are introduced into the gap through a needle connected to a syringe pump. These are then captured in the cores of the vortices (core bubble) and in the outflow regions along the inner cylinder (wall bubble). The flow field is measured with a two-dimensional particle imaging velocimetry (PIV) system. The motion of the bubbles is monitored by using a high speed video camera. It has been found that, if the core bubbles are all of the same size, a bubble ring forms at the center of the vortex such that bubbles are azimuthally uniformly distributed. There is a saturation number (N[subscript s]) of bubbles in the ring, such that the addition of one more bubble leads eventually to a coalescence and a subsequent complicated evolution. Ns increases with increasing rotation speed and decreasing bubble size. For bubbles of non-uniform size, small bubbles and large bubbles in nearly the same orbit can be observed to cross due to their different circulating speeds. The wall bubbles, however, do not become uniformly distributed, but instead form short bubble-chains which might eventually evolve into large bubbles. The motion of droplets and particles in a Taylor vortex was also investigated. As with bubbles, droplets and particles align into a ring structure at low rotation speeds, but the saturation number is much smaller. Moreover, at high rotation speeds, droplets and particles exhibit a characteristic periodic oscillation in the axial, radial and tangential directions due to their inertia. In addition, experiments with non-spherical particles show that they behave rather similarly. This study provides a better understanding of particulate behavior in vortex flow structures.

Core-Shell Assisted Bimetallic Assembly of Pt and Ru Nanoparticles by DNA Hybridization

We have discovered that the current protocols to assemble Au nanoparticles based on DNA hybridization do not work well with the small metal nanoparticles (e.g. 5 nm Au, 3.6 nm Pt and 3.2 nm Ru particles). Further investigations revealed the presence of strong interaction between the oligonucleotide backbone and the surface of the small metal nanoparticles. The oligonucleotides in this case are recumbent on the particle surface and are therefore not optimally oriented for hybridization. The nonspecific adsorption of oligonucleotides on small metal nanoparticles must be overcome before DNA hybridization can be accepted as a general assembly method. Two methods have been suggested as possible solutions to this problem. One is based on the use of stabilizer molecules which compete with the oligonucleotides for adsorption on the metal nanoparticle surface. Unfortunately, the reported success of this approach in small Au nanoparticles (using K₂BSPP) and Au films (using 6-mercapto-1-hexanol) could not be extended to the assembly of Pt and Ru nanoparticles by DNA hybridization. The second approach is to simply use larger metal particles. Indeed most reports on the DNA hybridization induced assembly of Au nanoparticles have made use of relatively large particles (>10 nm), hinting at a weaker non-specific interaction between the oligonucleotides and large Au nanoparticles. However, most current methods of nanoparticle synthesis are optimized to produce metal nanoparticles only within a narrow size range. We find that core-shell nanoparticles formed by the seeded growth method may be used to artificially enlarge the size of the metal particles to reduce the nonspecific binding of oligonucleotides. We demonstrate herein a core-shell assisted growth method to assemble Pt and Ru nanoparticles by DNA hybridization. This method involves firstly synthesizing approximately 16 nm core-shell Ag-Pt and 21 nm core-shell Au-Ru nanoparticles from 9.6 nm Ag seeds and 17.2 nm Au seeds respectively by the seed-mediated growth method. The core-shell nanoparticles were then functionalized by complementary thiolated oligonucleotides followed by aging in 0.2 M PBS buffer for 6 hours. The DNA hybridization induced bimetallic assembly of Pt and Ru nanoparticles could then be carried out in 0.3 M PBS buffer for 10 hours.

Effects of Air Pollution Control on Climate

Urban air pollution and climate are closely connected due to shared generating processes (e.g., combustion) for emissions of the driving gases and aerosols. They are also connected because the atmospheric lifecycles of common air pollutants such as CO, NOx and VOCs, and of the climatically important methane gas (CH4) and sulfate aerosols, both involve the fast photochemistry of the hydroxyl free radical (OH). Thus policies designed to address air pollution may impact climate and vice versa. We present calculations using a model coupling economics, atmospheric chemistry, climate and ecosystems to illustrate some effects of air pollution policy alone on global warming. We consider caps on emissions of NOx, CO, volatile organic carbon, and SOx both individually and combined in two ways. These caps can lower ozone causing less warming, lower sulfate aerosols yielding more warming, lower OH and thus increase CH4 giving more warming, and finally, allow more carbon uptake by ecosystems leading to less warming. Overall, these effects significantly offset each other suggesting that air pollution policy has a relatively small net effect on the global mean surface temperature and sea level rise. However, our study does not account for the effects of air pollution policies on overall demand for fossil fuels and on the choice of fuels (coal, oil, gas), nor have we considered the effects of caps on black carbon or organic carbon aerosols on climate. These effects, if included, could lead to more substantial impacts of capping pollutant emissions on global temperature and sea level than concluded here. Caps on aerosols in general could also yield impacts on other important aspects of climate beyond those addressed here, such as the regional patterns of cloudiness and precipitation.

Validez de apariencia y concurrente de un instrumento de evaluación de la discapacidad en personas con lesión medular crónica, basado en el core set abreviado de la cif

Objetivo. Determinar la validez de apariencia y concurrente de un instrumento de evaluación de la discapacidad en personas con lesión medular crónica (SCI-DAS), basado en el core set abreviadode la CIF. Metodología. Participaron 100 personas con lesión medular de más de seis meses de evolución de cuatro ciudades colombianas, así como ocho fisioterapeutas con una experiencia profesional promedio de 6,75 años. La validez de apariencia se evaluó a través de un grupo focal y una encuesta a los observadores, se calcularon los coeficientes de variación de los ítems y los índices de pertinencia y adecuación. Mediante el coeficiente de correlación de Spearman se analizó la validez concurrente con la escala de deficiencia AIS (American SpinalInjury Association[ASIA] Impairment Scale), y la escala de discapacidad WHO-DASII. Resultados. La pertinencia y adecuación global del instrumento arrojaron una media de 4,83/5 y 4,48/5 con un coeficiente de variación de 0,03. El índice de acuerdo entre observadores para las calificaciones de buena y excelente fue de 0,96 para pertinencia y 0,86 para adecuación. La discapacidad medida con el SCI-DAS mostró correlación significativa moderada con el nivel neurológico, los índice motor y sensitivo AIS, y alta con la discapacidad medida con el WHO-DAS II (p<0,001). Se encontró correlación baja estadísticamente marginal con la escala de compromiso funcional AIS (p=0,052). Conclusiones. Se encontró en general buena validez de apariencia del instrumento SCI-DAS, así mismo se evidenció la validez concurrente del instrumento SCI-DAS con la escala de deficiencia AIS y con la Escala de Discapacidad de la OMS-WHO-DAS II.

Implementation of ‘School Back’ by the ‘Core’ technique in a factory of geotextiles to prevent back pain

Introduction: This article aims to show an alternative intervention for the prevention and control of back pain to the people of a production plant of geotextiles for the construction exposed to handling and awkward postures through the implementation of the Back School using the CORE technique. This technique being understood as trainer of the stability musculature of the spine; whose benefit is proportionate the muscular complex of the back, stability and avoid osteomuscular lesions and improved posture. Objective: To present the results about the implementation of the back school by the CORE technique for prevention of back pain in a population of forty-eight male collaborators. Materials and methods: The back school began with talks of awareness by the occupational health physician explaining the objectives and benefits of it to all participants. Once this activity was done, was continued to evaluate all plant employees to establish health status through the PAR-Q questionnaire, who were surveyed for the perception of pain using visual analog scale (VAS) and stability was determined column through the CORE assessment, to determine the training plan. Then, were made every six months the revaluations and implementation of a survey of assistant public perception to identify the impact of the implementation of the school back on the two variables referred (pain perception and stability of column). Results: The pain perception according VAS increased in the number of workers asymptomatic in 12% and based in the satisfaction survey 94% of population reported that with the development of this technique decrease the muscle fatigue in lumbar level; and 96% of population reported an improvement in the performance of their work activities. Discussion: Posterior to the analysis of all results, it is interpreted that back schools practice through CORE technique, contributes to the prevention and / or control of symptoms at the lumbar level in population of productive sector exposed to risks derived from the physical load, provided that ensure its continuously development and supervised for a competent professional.

Experiment with air.

Realiza experimentos con aviones de papel, botellas de plástico, instrumentos musicales de viento caseros, globos llenos de aire caliente, paracaidas, para explicar las propiedades del aire.Tiene un glosario.Para alumnos de primaria.

Air.

Explica por qué el aire es importante para la vida vegetal y animal. Se analiza cómo algunos inventos han dependido de él, y se sugieren actividades que demuestren sus propiedades.

I can help clean our air.

Analiza las formas prácticas en las que los niños pueden proteger el medio ambiente. Sencillas actividades para mostrar cuáles son los problemas, y sugerir la forma en que pueden participar en la preservación de los recursos naturales del planeta a través del reciclaje. Le cuenta a los lectores cual es la composición del aire que respiramos, por qué es importante para nosotros, la forma en que está contaminado y lo que podemos hacer para mantenerlo limpio y saludable.

Geography 360õ : core book 1.

Su contenido se adapta a la llamada etapa tres (key stage tres) y, en concreto, a los alumnos de los niveles tres al cinco. Proporciona un gran número de actividades para la práctica de habilidades geográficas, que pueden realizarse a nivel individual y también en clase; incluye, también, evaluación periódica de los alumnos sobre cada uno de los temas de este programa.

Oxford maths zone. Year 3. Core book.

Contiene una amplia gama de recursos destinados a enseñar a los niños cómo usar las matemáticas en el mundo real, su pertinencia y relevancia; también ofrece orientación sobre las principales actividades para cada uno de los niveles. Cumple con los requisitos del National Numeracy Strategy en cuanto a los conocimientos básicos de aritmética que proporciona y a toda la secuencia de material didáctico que le acompaña.

AQA GCSE science core foundation.

Esta serie de compone de dos libros, uno para el profesor y otro para los alumnos. El primero de ellos tiene preguntas y otros recursos que refuerzan los conocimientos de los temas expuestos en el libro del estudiante. En éste, el texto desarrolla un enfoque analítico y de evaluación de los problemas y las cuestiones científicas, para que los alumnos comprendan la naturaleza de la ciencia y su importancia para ellos mismos y la sociedad.

Edexcel GCSE english and english language : core. Student book.

Esta formado de dos especificaciones distintas: Inglés y Lengua inglesa, con calificaciones separadas en los exámenes del General Certificate Secondary Education (GCSE) Edexcel. Se divide en cinco unidades, cada una de ellas integrada por varias lecciones y con sus propios objetivos de aprendizaje. Su contenido ayuda a desarrollar las habilidades de lectura y escritura. Incluye actividades de evaluación y distintas evaluaciones de control.

Edexcel GCSE english and english language : core. Teacher guide.

Este recurso para los profesores incorpora las novedades introducidas en las especificaciones a partir de septiembre de 2010 en el General Certificate Secondary Education (GCSE) Edexcel. Su contenido se divide en dos grandes secciones: lecciones visuales y evaluaciones de control. Las lecciones se apoyan en el libro del alumno y muestran cómo la utilización conjunta de los recursos impresos y digitales para dar las lecciones mejoran las calificaciones de los estudiantes. En cuanto a la segunda parte, proporciona asesoramiento específico sobre las evaluaciones de control de las nuevas especificaciones.

The Minimum core for language and literacy : knowledge, understanding and personal skills.

Guía práctica sobre lenguaje y alfabetización para profesores en formación (nivel bachillerato). Les permite identificar y desarrollar sus propias habilidades lingüísticas y de alfabetización y al mismo tiempo apoyar la evolución de los alumnos. Contiene todas las áreas claves de conocimiento, compresión y habilidades personales, además de analizar en un contexto amplio cómo el lenguaje y la alfabetización se adquieren y se desarrollan a nivel personal, social y cultural. El contenido está adaptado para la obtención de los certificados QTLS (Qualified Teacher, Learning and Skills) y ATLS (Associate Teacher, Learning and Skills).