A procedure based on branch-and-bound for the Cyclic Hoist Scheduling Problem

When various kinds of products must receive the same treatments in a production line of tanks and the size of batches is high, a cyclic manufacturing composed of a job from each batch can be scheduled. A hoist ensures the auto- mated transfer of the jobs between tanks. The probl em consists in the scheduling of repetitive hoist movements, which is known as CHSP (Cyclic Hoist Scheduling Problem). The objective is to find a sequence which minimizes the cycle time for jobs from different products. We consider the problem where types of products must be treated and we search an n-cyclic schedule. The algorithm is based on the resolution of different sequences of products. For each one, a branch-and-bound is solved which considers only coherent subsequences. It enables to reduce the com- putational times most of the time for instances with 5 tanks and 4 product typesPostprint (published version

New computational experiences on the Hoist Scheduling Problem for cyclic manufacturing of different products.

Jobs of two products must receive the same treatments in a production line of tanks. If the size of both batches is equal, we propose a cyclic manufacturing composed of a job from batch 1 and a job from batch 2. A hoist ensures the transfer of the jobs between tanks. The problem consists in the scheduling of hoist movements, which is known as HSP (Hoist Scheduling Problem). There is a comparison between completely separated and mixed production for both batches. The objective is to determine a sequence which minimises the cycle time for two jobs from different products (2-product cycle). We propose a branch-and-bound procedure, which can also be applied to the 2-cycle case for a single product. The model can be extended to ncycles

Performance Evaluation of Surface Mining Equipment with Particular Reference to Shovel-Dumper Mining

Surface mining is the most well-known mining around the world, and open pit mining accounts for more than 60% of all surface yield. Haulage costs represent as much as 60% of the aggregate working expense for these type of mines, so it is desirable to keep up an effective haulage framework. Equipment availability and estimation of utilization very precisely which is very important since mine manager wants to utilize their equipment as effectively as possible to get an early return of their investment as well as reducing total production cost. In present situation to achieve high production and productivity of HEMMs in opencast mines, it is desired to have high % availability and % utilization of equipment besides ensure overall equipment effectiveness as per CMPDI norms/global bench marks. OEE shows that how an equipment is utilized with its maximum effectiveness. It uses parameters like availability, performance and utilization for the estimation of equipment effectiveness. One method for effectively use of equipment in haul cycle is queuing theory. Queuing theory was developed to model systems that provide service for randomly arising demands and predict the behaviour of such systems. A queuing system is one in which customers arrive for service, wait for service if it is not immediately available, and move on to the next server or exit the system once they have been serviced. Most mining haul routes consist of four main components: loading, loaded hauling, dumping, and unloaded hauling to return to the loader. These components can be modelled together as servers in one cyclic queuing network, or independently as individual service channels. Data from a large open pit mine are analysed and applied to a multichannel queuing model representative of the loading process of the haul cycle. The outputs of the model are compared against the actual dumper data to evaluate the validity of the queuing model developed

The hArtes Tool Chain

This chapter describes the different design steps needed to go from legacy code to a transformed application that can be efficiently mapped on the hArtes platform

Biopsychosocial Assessment and Ergonomics Intervention for Sustainable Living: A Case Study on Flats

This study proposes an ergonomics-based approach for those who are living in small housings (known as flats) in Indonesia. With regard to human capability and limitation, this research shows how the basic needs of human beings are captured and analyzed, followed by proposed designs of facilities and standard living in small housings. Ninety samples were involved during the study through in- depth interview and face-to-face questionnaire. The results show that there were some proposed of modification of critical facilities (such as multifunction ironing work station, bed furniture, and clothesline) and validated through usability testing. Overall, it is hoped that the proposed designs will support biopsychosocial needs and sustainability

A catalog of stream processing optimizations

Cataloged from PDF version of article.Various research communities have independently arrived at stream processing as a programming model for efficient and parallel computing. These communities include digital signal processing, databases, operating systems, and complex event processing. Since each community faces applications with challenging performance requirements, each of them has developed some of the same optimizations, but often with conflicting terminology and unstated assumptions. This article presents a survey of optimizations for stream processing. It is aimed both at users who need to understand and guide the system's optimizer and at implementers who need to make engineering tradeoffs. To consolidate terminology, this article is organized as a catalog, in a style similar to catalogs of design patterns or refactorings. To make assumptions explicit and help understand tradeoffs, each optimization is presented with its safety constraints (when does it preserve correctness?) and a profitability experiment (when does it improve performance?). We hope that this survey will help future streaming system builders to stand on the shoulders of giants from not just their own community. © 2014 ACM