Stock Pieces Research Articles

Infrastructure Management System

Technology cannot be disregarded because it has raised the living standards and sparked revolutions in many facets of contemporary society. In every industry, technology has decreased labor and time requirements, and enhanced production efficiency. A certain technology's innovation eventually makes it a part of society and essential to people's daily lives. The management of infrastructure manually in any organization or institution is a tedious task. In order to make the management of infrastructure in courts automated, an application is developed that maintains every detail of all infrastructures and IT stocks in the courts. Users can view the purchase date, warranty period, and location of the infrastructure in the court. A unique QR code is generated for each piece of furniture and IT stock to access its details. The Infrastructure Management System is touted as a revolution in court management. This application saves time and workload. Moreover, notifications are generated if the service period is nearing, and it would call the service person regarding the repair and service. This management system is found to be effective and efficient.

Approximation Algorithms for Constructing Steiner Trees in the Euclidean Plane $$\mathbb {R}^2$$ Using Stock Pieces of Materials with Fixed Length

Approximation Algorithms for Constructing Steiner Trees in the Euclidean Plane $$\mathbb {R}^2$$ Using Stock Pieces of Materials with Fixed Length

Maria Edgeworth’s Private Theatricals: Patronage, Zara, and 1814

ABSTRACT Maria Edgeworth’s Patronage is one of a number of novels by women published in 1814 that refer to private theatricals, the most famous of which is Austen’s Mansfield Park. Edgeworth was familiar with the custom of private theatricals in Ireland where her family performed plays and she also attended a performance at the celebrated season of amateur performances in Kilkenny that began in 1802 and lasted until 1819. In this article, I discuss the relevance of these Irish contexts for the intertextual and intertheatrical dimensions of the play staged in Patronage, Aaron Hill’s 1735 tragedy Zara. A translation of Voltaire’s Zaïre (1732), Hill’s tragedy was a stock piece in the theatrical repertoire and was included in the influential 1808 collection of plays entitled The British Theatre, edited by Edgeworth’s friend Elizabeth Inchbald. I explore the relationship of Zara with another early Georgian tragedy mentioned in Patronage as a possible choice for the performers, Joseph Addison’s Cato (1713). The theatricals episode is important for Edgeworth’s exploration in Patronage of a number of intersecting themes that resonate with Edgeworth’s own literary celebrity around 1814: the relationship between the novel and the theatre, gender and genre, and cosmopolitanism and translation.

Approximation algorithms for constructing required subgraphs using stock pieces of fixed length

In this paper, we address the problem of constructing required subgraphs using stock pieces of fixed length (CRS-SPFL, for short), which is a new variant of the minimum-cost edge-weighted subgraph (MCEWS, for short) problem. Concretely, for the MCEWS problem Q, it is asked to choose a minimum-cost subset of edges from a given graph G such that these edges can form a required subgraph $$G'$$. For the CRS-SPFL problem $$Q^{\prime }$$, these edges in such a required subgraph $$G'$$ are further asked to be constructed by plus using some stock pieces of fixed length L. The new objective, however, is to minimize the total cost to construct such a required subgraph $$G'$$, where the total cost is sum of the cost to purchase stock pieces of fixed length L and the cost to construct all edges in such a subgraph $$G'$$. We obtain the following three main results. (1) Given an $$\alpha $$-approximation algorithm to solve the MCEWS problem, where $$\alpha \ge 1$$ (for the case $$\alpha =1$$, the MCEWS problem Q is solved optimally by a polynomial-time exact algorithm), we design a $$2\alpha $$-approximation algorithm and another asymptotic $$\frac{7\alpha }{4}$$-approximation algorithm to solve the CRS-SPFL problem $$Q^{\prime }$$, respectively; (2) When Q is the minimum spanning tree problem, we provide a $$\frac{3}{2}$$-approximation algorithm and an AFPTAS to solve the problem $$Q^{\prime }$$ of constructing a spanning tree using stock pieces of fixed length L, respectively; (3) When Q is the single-source shortest paths tree problem, we present a $$\frac{3}{2}$$-approximation algorithm and an AFPTAS to solve the problem $$Q^{\prime }$$ of constructing a single-source shortest paths tree using stock pieces of fixed length L, respectively.

Numerical simulation of friction stir butt-welding of 6061 aluminum alloy

Abstract A two-dimensional computational fluid dynamics model was established to simulate the friction stir butt-welding of 6061 aluminum alloy. The dynamic mesh method was applied in this model to make the tool move forward and rotate in a manner similar to a real tool, and the calculated volumetric source of energy was loaded to establish a similar thermal environment to that used in the experiment. Besides, a small piece of zinc stock was embedded into the workpiece as a trace element. Temperature fields and vector plots were determined using a finite volume method, which was indirectly verified by traditional metallography. The simulation result indicated that the temperature distribution was asymmetric but had a similar tendency on the two sides of the welding line. The maximum temperature on the advancing side was approximately 10 K higher than that on the retreating side. Furthermore, the precise process of material flow behavior in combination with streamtraces was demonstrated by contour maps of the phases. Under the shearing force and forward extrusion pressure, material located in front of the tool tended to move along the tangent direction of the rotating tool. Notably, three whirlpools formed under a special pressure environment around the tool, resulting in a uniform composition distribution.

Analisis Perbandingan Abnormal Return,Trading Volume Activity, dan Bid-Ask Spread Sebelum dan Sesudah Stock Split

Stock splits or stock split is to break a piece of stock into n shares so that the new price per share after the stock split is 1 / n of the previous price.This study aims to investigate the market reaction to the announcement of the stock split the company listed in Indonesia Stock Exchange Period 2012-2013. The market reaction is indicated by the presence or absence of abnormal return differences, trading volume activity, and bid-ask spreads before and after the stock split announcement.Type of research is a study of events (event study).The study sample as many as 17 companies based on purposive sampling.Testing is done with a period of 5 days before and 5 after the announcement of the stock split.The technique of data analysis performed using paired sample t-test on abnormal returns while Wilcoxon signed ranks test on trading volume activity and bid-ask spreads.

Approximation algorithms for constructing specific subgraphs with minimum number of length-bounded stock pieces

Motivated by the Steiner tree problem with minimum number of Steiner points and bounded edge-length in [4], we consider the problem of constructing specific subgraph with minimum number of length-bounded stock pieces (CSS-MSP, for short), which is defined as follows. In some constructing specific subgraph problem Q (CSS, for short), the objective is to choose a minimum-length subset of edges, such that these edges form a specific subgraph (such as a spanning tree or a Steiner tree). In the CSS-MSP problem Q′, these edges are further required to be cut from some stock pieces of length L, and the new objective, however, is to minimize the number of stock pieces of length L to construct all edges in such a specific subgraph.We obtain two main results. (1) Whenever the CSS problem Q can be approximated by an α-approximation algorithm (α≥1) (for the case α=1, the CSS problem Q is solved optimally by a polynomial-time exact algorithm), we design two approximation algorithms with performance ratios 2α and 7α4 to solve the CSS-MSP problem Q′; (2) In addition, when the problem Q is to find a minimum spanning tree, we present a 32-approximation algorithm and an APTAS to solve the problem Q′ of constructing spanning tree with minimum number of length-bounded stock pieces.

Nonlinear dynamic simulation and control of large-scale reheating furnace operations using a zone method based model

Modern reheating furnaces are complex nonlinear dynamic systems having heat transfer performances which may be greatly influenced by operating conditions such as stock material properties, furnace scheduling and throughput rate. Commonly, each furnace is equipped with a tailored model predictive control system to ensure consistent heated product quality such as final discharge temperature and temperature uniformity within the stock pieces. Those furnace models normally perform well for a designed operating condition but cannot usually cope with a variety of transient furnace operations such as non-uniform batch scheduling and production delay from downstream processes. Under these conditions, manual interventions that rely on past experience are often used to assist the process until the next stable furnace operation has been attained. Therefore, more advanced furnace control systems are useful to meet the challenge of adapting to those circumstances whilst also being able to predict the dynamic thermal behaviour of the furnace. In view of the above, this paper describes in detail an episode of actual transient furnace operation, and demonstrates a nonlinear dynamic simulation of this furnace operation using a zone method based model with a self-adapting predictive control scheme. The proposed furnace model was found to be capable of dynamically responding to the changes that occurred in the furnace operation, achieving about ±10 °C discrepancies with respect to measured discharge temperature, and the self-adapting predictive control scheme is shown to outperform the existing scheme used for furnace control in terms of stability and fuel consumption (fuel saving of about 6%).

Approximation algorithms for constructing spanning K-trees using stock pieces of bounded length

Given a weighted graph G on $$n + 1$$ vertices, a spanning K-tree $$T_K$$ of G is defined to be a spanning tree T of G together with K distinct edges of G that are not edges of T. The objective of the minimum-cost spanning K-tree problem is to choose a subset of edges to form a spanning K-tree with the minimum weight. In this paper, we consider the constructing spanning K-tree problem that is a generalization of the minimum-cost spanning K-tree problem. We are required to construct a spanning K-tree $$T_K$$ whose $$n+K$$ edges are assembled from some stock pieces of bounded length L. Let $$c_0$$ be the sale price of each stock piece of length L and $$k(T_K)$$ the number of minimum stock pieces to construct the $$n+K$$ edges in $$T_K$$ . For each edge e in G, let c(e) be the construction cost of that edge e. Our new objective is to minimize the total cost of constructing a spanning K-tree $$T_K$$ , i.e., $$\min _{T_K}\{\sum _{e\in T_K} c(e)+ k(T_K)\cdot c_0\}$$ . The main results obtained in this paper are as follows. (1) A 2-approximation algorithm to solve the constructing spanning K-tree problem. (2) A $$\frac{3}{2}$$ -approximation algorithm to solve the special case for constant construction cost of edges. (3) An APTAS for this special case.

Toward a Prehistory of Film Music

Photoplay music is a genre that took shape during the “silent” period of cinema when extended narrative films became mass entertainment. Many photoplay pieces exhibit certain structural features that we propose to conceptualize as modular form: They consist of several brief segments (often indicated by double barlines and numbers) that are easy to rearrange and flexible in themselves. Hans Erdmann’s Fantastisch-romantische Suite, derived from his original Nosferatu score, is such a set of musical modules designed to accompany various films in ad hoc arrangements–a purpose supported not only by numerous breaking points but also by their harmonic, syntactic and textural design. While modular techniques persisted in the era of sound film well after 1930, they also continued certain practices of theatrical music of the 19th and early 20th centuries, such as compilation and quick arrangement of stock pieces in ballet, vaudeville, pantomime, and spoken drama.

Nonstoichiometry and growth of some Fe carbides

Iron carbides containing from 31 to 17 atomic % carbon, with cohenite XRD structure and optical properties, were grown in experiments in Fe–Ni–S–C, Fe–Ni–C, and in Fe–C at 1, 6, and 7 GPa. X-ray cell volumes increase with C content. Compositions listed above vary considerably outside the nominal (Fe,Ni)3C stoichiometry of cohenite/cementite. Cohenites coexisting with Fe–C liquid are carbon poor. The Eckstrom-Adcock carbide, nominally Fe7C3, was found to show compositions from 29 to 36 atomic % C at 7 GPa in Fe–C. Both these materials are better regarded as solutions than as stoichiometric compounds, and their properties such as volume have compositional dependencies, as do the iron oxides, sulfides, silicides, and hydrides. The fraction of C dissolved in cohenite-saturated alloy is found to become smaller between 1 and 7 GPa. If this trend continues at higher pressures, the deep mantle should be easier to saturate with carbide than the shallow mantle, whether or not carbide is metastable as at ambient pressure. At temperatures below the cohenite-graphite peritectic, cohenite may grow as a compositionally zoned layer between Fe and graphite. The Eckstrom-Adcock carbide joins the assemblage at 7 GPa. Phases appear between Fe and C in an order consistent with metasomatic interface growth between chemically incompatible feed stocks. Diffusion across the carbide layer is not the growth rate limiting step. Carbon transport along the grain boundaries of solid Fe source stock at 1 GPa, to form C-saturated Fe alloy, is observed to be orders of magnitude faster than the cohenite layer growth. Growth stagnates too rapidly to be consistent with diffusion control. Furthermore, lateral variations in carbide layer thickness, convoluted inert marker horizons, and variable compositional profiles within the layers suggest that there are local transport complexities not covered by one-dimensional diffusive metasomatic growth. In contrast to many transport phenomena which slow with pressure, at 7 GPa and 1,162 °C, carbide growth without open grain boundaries is faster than at 1 GPa with fast grain boundary channels, again suggesting C transport is less of a constraint on growth than C supply. C supply at 7 GPa is enhanced by graphite metastability and the absence of fast grain boundary channels to divert C into the Fe instead of growing carbide. At both 1 and 7 GPa, the growth rate of carbide is found to systematically vary depending on which of two stock pieces of graphite are used to form the growth couple, suggesting that some property of each specific graphite, like C release rate, possibly from amorphous binder material, may influence the cohenite growth process. At temperatures near and above the cohenite-graphite peritectic at 1–1.5 GPa, complex intergrowths involving Fe–C liquids and extensive thermal migration transport were encountered, eroding the organized spatial resolution, and the range of cohenite compositions found grown below this peritectic from growth couples of crystalline Fe and graphite. The migration of graphite to a position in the metasomatic sequence between liquid and cohenite demonstrates that the solubility of graphite in liquid increases with temperature above the peritectic, whereas the solubility of graphite in cohenite below the peritectic decreases with temperature. The variable solubility of graphite in cohenite, shown by thermal migration, emphasizes that cohenite does have compositional variations.

Calculating the Exploitation Costs of Trains in the Spanish Railways

The Spanish railway network has two different track gauges, two electrification systems, and four families of signaling systems--and the rolling stock includes hybrid trains. The new, extended package presented here finds the timings and best route for any piece of rolling stock and computes its consumption, emissions, and exploitation costs.

Optimization of a line-cutting procedure for ship hull construction by an effective tabu search

A problem of a line-cutting procedure is discussed for ship hull construction. This procedure includes five steps: stock arrangement, piece arrangement, marking, cutting and special processes, and delivering the work. The line-cutting procedure will be optimized when two objectives are considered: minimizing the total trim loss and keeping the working efficiency of the cutting procedure. The developed way for the discussed problem is to optimize the stock arrangement associated with a proposed rule-based piece arrangement where the former is optimized for minimizing the total trim loss and the latter for keeping the working efficiency. A tabu search is chosen for the optimization of stock arrangement. In addition, two proposed replacement moves, the aggregative and the breaking, are adopted to improve the effectiveness of the tabu search. Two real cases and some random instances are used for test and comparison. The results show that the stock arrangement was optimized satisfyingly by the tabu search and the rule-based piece arrangement is capable of keeping the working efficiency as usual. In addition, the effectiveness of the tabu search was apparently improved by two proposed replacement moves.

A Nested Decomposition Approach to a Three-Stage, Two-Dimensional Cutting-Stock Problem

We consider the cutting of rectangular order pieces into stock pieces of specified width and length. The cutting process involves three stages of orthogonal guillotine cutting: Stock pieces are cut into sections that are cut into slits that are cut into order pieces. Restrictions imposed on the cutting process make the combinatorial structure of the problem more complex, but limit the scope of solution space. The objective of the problem is mainly to minimize waste, but our model also accounts for other issues such as aging stock pieces, urgent or optional orders, and fixed setup costs. Our solution approach involves a nested decomposition of the problem and the recursive use of the column-generation technique: We use a column-generation formulation of the problem (Gilmore and Gomory 1965) and the cutting-pattern—generation subproblem is itself solved using a column-generation algorithm. LP-based lower bounds on the minimum cost are computed and, by rounding the LP solution, a feasible solution and associated upper bound is obtained. This approach could in principle be used in a branch-and-bound search to solve the problem to optimality. We report computational results for industrial instances. The algorithm is being used in industry as a production-planning tool.

APPROXIMATION ALGORITHM FOR MULTIPLE-TOOL MILLING

Milling is the mechanical process of removing material from a piece of stock through the use of a rapidly spinning circular milling tool in order to form some desired geometric shape. An important problem in computer-aided design and manufacturing is the automated generation of efficient milling plans for computerized numerically controlled (CNC) milling machines. Among the most common milling problems is simple 2-dimensional pocket milling: cut a given 2-dimensional region down to some constant depth using a given set of milling tools. Most of the research in this area has focused on generating such milling plans assuming that the machine has a tool of a single size. Since modern CNC milling machines typically have access to a number of milling tools of various sizes and the ability to change tools automatically, this raises the important optimization problem of generating efficient milling plans that take advantage of this capability to reduce the total milling time. We consider the following multiple-tool milling problem: Given a region in the plane and a set of tools of different sizes, determine how to mill the desired region with minimum cost. The problem is known to be NP-hard even when restricted to the case of a single tool. In this paper, we present a polynomial-time approximation algorithm for the multiple-tool milling problem. The running time and approximation ratio of our algorithm depend on the simple cover complexity (introduced by Mitchell, Mount, and Suri) of the milling region.

A matching approach for replenishing rectangular stock sizes

Consider a replenishment problem in which several different rectangular sizes of material are stocked. Customers order rectangles of the material, but the rectangles ordered have a range on specified width as well as on specified length. To satisfy the customer requirements, the stock material can be cut once longitudinally in order to satisfy two customer requirements or not cut at all, that is, an entire stock piece of material is used to satisfy one customer requirement. If an exact match is impossible in the current planning period, the unused material must be returned to stock— an expensive and undesirable situation. In this paper, a nonbipartite weighted matching problem formulation will be given for determining the replenishment requirements of rectangular stock sizes. Then, a hybrid solution approach, capable of solving real applications (typically up to 3000 nodes) efficiently, will be discussed. This solution was implemented in September 1998 and has operated successfully since then.

Exact Solution of the Two-Dimensional Finite Bin Packing Problem

Given a set of rectangular pieces to be cut from an unlimited number of standardized stock pieces (bins), the Two-Dimensional Finite Bin Packing Problem is to determine the minimum number of stock pieces that provide all the pieces. The problem is NP-hard in the strong sense and finds many practical applications in the cutting and packing area. We analyze a well-known lower bound and determine its worst-case performance. We propose new lower bounds which are used within a branch-and-bound algorithm for the exact solution of the problem. Extensive computational testing on problem instances from the literature involving up to 120 pieces shows the effectiveness of the proposed approach.

An algorithm for the 2D guillotine cutting stock problem

The two-dimensional guillotine cutting stock problem seeks to apply a sequence of guillotine (edge to edge) cuts to extract a collection of smaller rectangles from a stock piece. In this paper an O( n 3) approximation algorithm for the two-dimensional guillotine cutting stock problem is presented. The algorithm considers each rectangle, in turn, and attempts to locate a guillotine feasible position on the stock piece. The algorithm has the property that a position will be located for the n-th rectangle if and only if such a feasible placement exists. This paper establishes the efficiency and effectiveness of the new algorithm by presenting computational results.

A comparison of solution methods for the assortment problem

The problem of economically cutting a required bill of material out of standard size stock pieces is shared by the metal, leather, glass, electronic, shipbuilding, and lumber industries. One of the problems in this area is the assortment problem; that is, determining the best combination of stock sizes to keep in inventory to cut a single known (deterministic) bill of material. This problem includes determining the dimensions or the stock pieces as well as the number of unique sizes to stock. In this research a comparison is made between three common heuristic methods for solution of the assortment problem and the introduction of the application of optimization homotopy to the assortment problem, a method developed for the solution of stochastic problems. It is found that while utilizing a specific combination of nesting and sequencing algorithms, the three heuristic methods work very well for simpler problems, and as the complexity of the problem increases optimization homotopy becomes more advantageous.

"The Milano Lessons" by Tadeusz Kantor: Introduction

Tadeusz Kantor, the late Polish visual artist and theatre director, is most widely known as the creator of The Dead Class (I975), Wielopole, Wielopole (1980), Let the Artists Die (1985), and I Shall Never Return (1988). Kantor is less well-known as a teacher. In June 1986 he taught a group of I I students at the Milan Civica scuola d'arte drammatica and, after a month of explorations, the students presented The Wedding Ceremony in two versions: one built according to the principles of constructivism, the other, surrealism. The Wedding Ceremony was not, however, a finished spectacle, but a theatrical journey into the process of artistic cognizance. In the constructivist Wedding Ceremony, the student performers raised onstage an assemblage made out of stock pieces found in a prop room-a slanted rostrum, wooden boards, a scaffold, a ladder, a bicycle wheel, hoops. A bishop, an altar boy, a sacristan, a chronicler, a bride, her sister, a bridegroom, and their parents gathered to participate in a holy matrimony: