A Heuristic Approach for Two-Dimensional Rectangular Cutting Stock Problem considering Balance for Material Utilization and Cutting Complexity

The common staged patterns are always required during the cutting process for separating a set of rectangular items from rectangular plates in manufacturing industries. Two-staged patterns can reduce cutting complexity at the expense of material utilization; three-staged patterns do the opposite. Combining these two types of staged patterns may be a good balance for two contradictory objectives of material utilization and cutting complexity. A heuristic approach is proposed to solve the two-dimensional rectangular cutting stock problem with a combination of two-staged general patterns (2SGP) and three-staged homogenous patterns (3SHP). Firstly, the 2SGP and 3SHP are constructed by using recursive techniques. The pattern with the larger value is selected as the candidate pattern. Then, the value of each item is corrected according to the current candidate pattern. A cutting plan accurately satisfying all items demand is obtained by using the sequential heuristic algorithm. Finally, the cutting plan with a minimum number of used plates is achieved by applying the iterative algorithm. The computational results indicate that the proposed heuristic approach is more effective in material utilization and cutting complexity than the two published algorithms with staged patterns.

Mathematical model of steel consumption minimization considering the two-stage billets cutting

Purpose. To achieve a decrease in energy and resource costs in the multi-stage production of rolled products within a given plan through the development of appropriate mathware. Methodology. The multi-stage problem mathware for producing rolling steel products is developed on the basis of system approach applying fundamental principles of the optimization and operation research theory. Realization of the developed mathematical model allows discovering such a strategy of using steel during the whole manufacturing process, which minimizes not only the steel waste at the moment of its casting in a mold, but also the offcuts in the process of cutting the obtained ingots into the billets. Findings. A mathematical task model is built to minimize the amount of steel for producing a certain order of size of one cast volume only. The developed model specifies the possibility to pre-evaluate the billet optimal size, based on the necessary cutting along the final product length, appropriate for the certain billet form of section, and ingot weight limits. Originality. A mathematical model is provided for the optimal metal distribution process when implementing the plan of manufacturing rolling products. The model, in contrast to the existing ones, shifts the emphasis on forming the optimal ingot weight, which has a pre-calculated optimal cutting plan. Practical value. The use of the developed mathematical optimization model (minimizing the amount of steel for producing a certain order) as part of an automated decision support system for management of rolling production will reduce the number of cutting machine changeover and minimize resources use and stock balance.

Material Effectiveness Model for the Construction of Aluminum Hull

Construction of a hull generally requires several plates and profile material. Early indications for shipbuilding indicate that in manner, the linear function approach for installed material was 75% to 90%, and waste material was 10% to 25%. This study is conducting an assessment of the area of installed material and waste material on small vessels made of aluminum with variations in ship length and the method of approach trend lines both linear and nonlinear. Secondary data retrieval in the form of an aluminum cutting plan for plate material and profile from the AutoCAD application, which is then reprocessed through the FastCAM application to obtain results in the form of identification of installed material and waste material area. Based on variations in ship length and material area results, a scatter plot process was carried out through the Excel application to obtain results in the form of trend line functions with an R-squared determination coefficient of more than 0.9 and the results of the calculation of the intersection between the function of installed material and waste material, and the waste material function with the x-axis uses the balance method. The final result showed that the linear function gives an indication of the effectiveness of the material located in the range of 6 to 23 meters in length of the boat and polynomial function of order 2 in the range of 6 to 18 meters in length, while the waste material area in the two functions maximum 22%.

The estimation of the number of OE-chains and realizable OE-routes for cutting plans with combined contours

Cuts combination of plane details leads to optimization of material use and shortening of cutting time. However, the problem of cutting plan realization arises. This plan has to satisfy the following restrictions: (1) part cut off a sheet does not require further cuts (constructing of OE-route); (2) there are some restrictions on placement of pierce points (constructing of PPOE-cover). In this paper we consider the problem of enumeration the OE-chains for cutting plan with combined cuts and necessary conditions of realizable cutting.

An Enhanced on Bidirectional LI-FI Attocell Access Point Slicing and Virtualization using Das2 Conspire

LiFi attocell get to systems will be conveyed wherever to help different applications and administration provisioning to different end-clients. The LiFi foundation suppliers should offer LiFi passages (APs) assets as an administration. This, be that as it may, requires an exploration test to be fathomed to progressively and adequately allot assets amonspecialist co-ops (SPs), while ensuring execution detachment among them and their separate clients. This paper presents an autonomic asset cutting (virtualization) conspire, which acknowledges autonomic administration and setup of virtual APs, in a LiFi Attocell get to arrange, in light of SP’s and their clients benefit necessities. The proposed asset cutting plan gathers and breaks down the movement insights of the distinctive applications upheld on the cuts characterized in each LiFi AP and appropriates the accessible assets reasonably and relatively among them. It utilizes a control calculation to change the base conflict window of client gadgets to accomplish the objective throughput and guarantee broadcast appointment decency among SP’s and their clients.

The Effect of Welding on the One-Dimensional Cutting-Stock Problem: The Case of Fixed Firefighting Systems in the Construction Industry

Safety is paramount in the construction industry and the fixed sprinkler and water spray systems used in firefighting involve networks of pipes of various lengths. Manufacturers of such fixed firefighting systems need to either cut the existing stocks to length—a (one-dimensional) cutting-stock problem—or lengthen the existing stocks or leftover segments through welding, a (one-dimensional) cutting-stock problem with welding. Best industry practice safety requirements allow only one weld per length of pipe. The case of a Hungarian manufacturer of fixed firefighting systems motivates this article, which argues that the cutting-stock problem with welding (with single- or multiple-size stocks) may be converted to an equivalent cutting-stock problem (with multiple-size stocks). Readily available algorithms and software may then be used to generate an optimal cutting plan for the equivalent cutting-stock problem. Subject to certain restrictions, the optimal cutting plan for the equivalent cutting-stock problem may then be converted to cutting patterns for the original cutting-stock problem with welding.

APLIKASI BUILDING INFORMASI MODELING (BIM) TEKLA STRUCTURE PADA KONSTRUKSI ATAP DOME GEDUNG OLAHRAGA UTP SURAKARTA

Pekembangan teknologi informasi dibidang konstruksi berkembang semakin pesat. Teknologi virtual building dengan sistem komputasi dikembangkan dengan prinsip Building Information Modeling (BIM), mampu menciptakan modeling secara 3D di bidang konstruksi (arsitektur, struktur dan MEP). Tekla Structures salah satu perangkat lunak berbasis BIM yang mampu membuat dan mengelola data akurat dan rinci. Tekla Structures mempunyai kemampuan dalam modeling, detailing, engineering, drawing, reporting, scheduling. Pembangunan atap dome baja menggunakan sistem truss pada Gedung Olahraga UTP Surakarta dengan bentang 40meter. Memerlukan detail drawing yang baik pada proses fabrikasi, sehingga didapatkan hasil yang presisi pada saat pemasangan. Proses pemasangan dilakukan secara segmented. Gambar fabrikasi atap dome terdiri dari Gambar Arrangement, Section drawing : Kuda-kuda K1 & K2, Anchor bolt plan, Lateral & Windbrace, Purlin & Sagrod, Detail drawing : Rafter 1 s/d 13, Cutting plan. Dan report bill of materials (BOM) terdiri dari Assembly List, Assembly Part List, Bolt List, Material List dan Part List.

Study of Abrasive Cutting of Natural Quartz for Manufacturing Piezoelectric Power Generators

The present study is related with the dicing of natural quartz crystals as part of the process manufacturing of a power generator device. Power generation is important, mainly for wifi systems, which use of batteries is restrictive or impossible due short dimensions and difficult of maintenance. The manufacturing dicing process applied in micro electromechanical systems (MEMS) is the main reference for this study, which objective is explores different parameters of dicing process and the impact of it in the final performance of the generator. Failure impregnation and productivity were study in blade and band saw process with different parameters as speed and cutting force. The natural quartz was selected mainly because availability in Brazil and piezoelectric properties. It was obtained substrates AT cutting plan with thickness of 2.5mm and width of 3mm. The material was tested under compressive stress and the correspondent electric signal was obtained.