Load-based generic polca: performance assessement using simulation

POLCA (i.e. Paired-cell Overlapping Loops of Cards with Authorization) is a card-based decision support system for production control, developed to support the adoption of Quick Response Manufacturing. Two variants of POLCA have been proposed in the literature to improve POLCA performance: Load Based POLCA and Generic POLCA. In this paper, we combine these two variants into a single production control system and analyse its performance for different backlog-sequencing rules. The results of a simulation study carried out for a make-to-order flow shop, support the strategy of combining these two POLCA variants and show that capacity-slack backlog sequencing based on corrected aggregate load have the potential for improving performance.info:eu-repo/semantics/publishedVersio

Экспериментальные исследования двухфазных течений в разгонных трубках струйных мельниц

Розроблено й виготовлена осесиметричну модель ежектора струминного млина для дослідження двофазних течій у розгінній трубці струминного млина. Схема даної моделі за-снована на класичній схемі ежектора. Відмінність від класичної схеми складається в наяв-ності каналу підведення додаткового потоку. Канал підведення має кільцеву форму й забез-печує подачу рівномірно розподіленого захисного потоку в розгінний канал через щілинний отвір. Проведено дослідження на осесимметричной моделі ежектора, що складалися із декі-лькох етапів, перший з яких полягав у вивченні характеру плину основного потоку в розгінній трубці млина, другий – у виявленні впливу додаткового потоку газу на основний потік, тре-тій – у виявленні впливу додаткового потоку газу, направленого до розгінної трубки під ку-том 30. Аналіз досліджень показав, що додатковий потік газу виконує захисну функцію й запо-бігає впливу основного потоку на стінки розгінного каналу. Знайдені переваги додаткового потоку газу ,підведеного під кутом, меншим 90. Виявлено необхідність досліджувати оптимальний кут підведення додаткового пото-ку газу.Разработана и изготовлена осесимметричная модель эжектора струйной мельницы для исследования двухфазных течений в разгонной трубке струйной мельницы. Схема данной модели основана на классической схеме эжектора. Отличие от классической схемы состо-ит в наличии канала подвода дополнительного потока. Канал подвода имеет кольцевую форму и обеспечивает подачу равномерно распределенного защитного потока в разгонный канал через щелевое отверстие. Проведены исследования на осесимметричной модели эжектора, состоящие из не-скольких этапов, первый из которых заключался в изучении характера течения основного потока в разгонной трубке мельницы, второй – в выявлении влияния дополнительного пер-пендикулярного потока газа на основной поток, третий – в выявлении влияния дополни-тельного потока газа, направленного в разгонную трубку под углом 30. Анализ исследований показал, что дополнительный поток газа выполняет защитную функцию и предотвращает влияние основного потока на стенки разгонного канала. Обна-ружены преимущества дополнительного потока газа, подведенного под углом, меньшим 90. Выявлена необходимость исследовать оптимальный угол подвода дополнительного потока газа.Axisymmetric model of the jet mill ejector are designed and manufactured for studing two-phase flows in jet mill accelerating tube. The scheme of this model is based on the classical scheme of the ejector. Unlike the classical scheme is the inlet channel of an additional flow presence. A channel for supplying has an annular shape and provides the protective uniformly distributed flow in acceler-ating channel through the slotted inlet. The researches on the axisymmetric ejector model are examined. They consisted of several stages, the first of which was to examine the main flow pattern in the mill accelerating tube, the sec-ond was to identify the additional gas flow impact on the main flow, the third – to identify the impact of the additional gas flow directed at an angle of 30 degrees into the accelerating tube. Analyses of studies have shown that the additional gas flow has a protecting function and pre-vents the main flow effect on the accelerating channel walls. The benefits of the additional gas flow fed at an angle of less than 90 degrees are discovered. The need of investigating the optimum angle of the additional gas flow feed is identified

Development and validation of a semiautomatic system for generation and deposition of sprays on isolated cells of the respiratory tract

A computer-controlled spray-generating and spray-exposure unit called RHINOCON was designed and constructed to offer the possibility of depositing, for example, environmental or pharmaceutical aerosols at the air/liquid interface under realistic exposure conditions. Here, isolated human respiratory cells are chosen to simulate, as far as possible, the in vivo situation. The exposure unit is equipped to hold up to 6 commercially available pump-spray dispensers, which are prepared mechanically for exposure as described in the manufacturer's users' guide. A transwell insert containing the cells is placed opposite each dispenser in a special plate head first. After starting the program, the spray dispensers are shaken and actuated automatically. The spray is released into an air flow passing over the cells, where the spray droplets are deposited due to their inertia. After exposure, the inserts can easily be removed and processed to measure a variety of cell toxicity parameters, such as cell viability or cell metabolism. Validation of the experimental setup was performed in an initial set of experiments: (1) by determination of the deposited amount of nebulized test substance on transwell membranes, and (2) by investigation of the cellular reactions of a human respiratory epithelial cell line (HFBE 21) exposed to nebulized hydrogen peroxide or to standard medium as a reference control

Testing of packages with LSA materials in very severe mechanical impact conditions with measurement of airborne release

To asses the risks associated with transport accidents involving solid LSA-II and LSA-III materials a comprehensive experimental programme was conducted to qantify and characterise airborne release of radioactive particulate matter in transport and handling accidents with mechanical impact of varying severities and to determine the dependency from influencing parameters such as LSA material and packaging properties and size. The experimental approach combined wellcontrolled and very reproducible impact experiments with small scale specimens and drop tests of larger scale specimens from different heights up to 27m. In both cases the associated airborne release of particulate matter is determined by measuring the amount and aerodynamic particle size characteristics of released dust. The small scale tests revealed fundamental results on airborne release and size distribution which helped to design the test matrix of the large scale experiments, especially with brittle material. In the large scale tests, volumes of specimens were varied systematically up to 200L and the LSA material was contained either within packaging or without protective packaging in order to determine the influence of the packaging on the airborne release and to be able to extrapolate other configurations of package sizes and impact severities. The LSA surrogate materials were either concrete, used to immobilize radioactive wastes as representive brittle material, or appropiately chosen powders representing dispersible materials. Based on the experimental results it can be concluded that the requirements of the current IAEA Transport Regulations sufficiently limit potential radiological consequences from transport accidents with mechanical impact involving packages with LSA-II or LSA-III materials

Smart Supply Chain – Development of the Equipment Supplier in Global Value Networks

Part 3: Product-Service Systems Customer-Driven Innovation and Value Co-creationInternational audienceDigitization and its effect on markets, production conditions, and intercompany interaction forces companies to adapt continuously in order to stay competitive. Factory equipment suppliers are especially affected by this development. Their customers expect them to digitalize their products and at the same time, request new service-based approaches in short periods. Ultimately, they are taking a new role within the automotive supply chain. With their smart products and solutions, factory equipment suppliers build the fundament to digitalize their customers. As suppliers of smart solutions, they will gain strategic importance in global value creation networks and smart supply chains. This paper examines the transformation of the equipment suppliers through the progressive networking of supply chains, using the automotive industry as an example. It shows how their new strategic role within the supply chain is developing and what requirements consequently arise

Towards the Generation of Setup Matrices from Route Sheets and Feedback Data with Data Analytics

Part 8: Knowledge Based EngineeringInternational audienceThe function or department of production control in manufacturing companies deals with short-term scheduling of orders and the management of deviations during order execution. Depending on the equipment and characteristics of orders, sequence dependent setup times might occur. In these cases for companies that focus on high utilization of their assets due to long phases of ramp up and high energy costs, it might be optimal to choose sequences with minimal setup time times between orders. Identifying such sequences requires detailed and correct information regarding the specific setup times. With increasing product variety and shorter lot sizes, it becomes more difficult and rather time intense to determine these values manually. One approach is to analyse the relevant features of the orders described in the route sheets or recipes to find similarities in materials and required tools. This paper presents a methodology, which supports setup optimized sequencing for sequence dependent setup times through constructing the setup matrix from such route sheets with the use of data analytics