Calculation of Three-dimensional Energy Product for Isotropic Nd2Fe14B Magnet

A conventional energy product calculated by the product of the B-field and the H-field is not sufficient for representing the performance of a magnet because it considers the homogeneous and only the uniaxial magnetic properties of the magnet. The conventional energy product has been compared with another energy product obtained by integrating the scalar product of the B-field and the H-field of each cell composed of the three-dimensional components. We investigated a model system by micromagnetic simulation using finite differential method (FDM) and calculated the full hysteresis of the magnet. The model system of a Nd2Fe14B magnet composed of grains with a diameter of about 100 nm was assumed. In the case of the isotropic multi-grain magnet, the energy product calculated by the integration method was 28% larger than the energy product obtained by the conventional way, although a discrepancy between the distribution of the magnetizations and the demagnetizing fields at the reversal process resulted in the decrease of the energy product

Economic Analysis for Investment of Public Sector’s Automated Container Terminal: Korean Case Study

The purpose of this case study is to conduct an economic analysis to calculate the proper terminal capacity of automated container terminal (ACT) investment from the perspective of the public sector. As a key element of smart port, the ACT is an important terminal operating facility for import/export and transshipment cargo between countries and must have facilities with sufficient capacity to load/unload export/import cargo in a timely manner according to the user’s request. Recently, the method of calculating the capacity of seaport infrastructure is changing from the method of applying the maximum capacity to the method of applying the proper capacity. Therefore, it is desirable to expand port facilities by investigating proper capacity rather than expanding port facilities based on the maximum performance. This study is a case study focusing on the new port of Busan introducing the ACT. From the perspective of national fiscal income and national economy from the ACT investment, this study determines the proper terminal capacity for each berth. As a result of economic analysis, the break-even terminal capacity to secure economic feasibility is from 544,272TEU of the nine berths to 600,138TEU of two berths applying a 2.96% discount ratio. In a sensitivity analysis considering the social discount rate and the change in the size of berths, the net present value has a positive value from a minimum of 530,000 TEU (nine berths with 1.96% social discount ratio) to a maximum of 620,000 TEU (three berths with 3.46% social discount ratio)

A high performance finite capacitated MRP process using a computational grid

A material requirement planning (MRP) process generates a production plan which guarantees an exact quantity of the right materials available at the needed time. Providing an executable production plan at high speed has remained a goal for MRP since the process was first developed in the 1970s. However, due to the time consuming characteristic of the process with its intensive database interaction, real time processing remained unattainable. Moreover, this performance issue became worse, as the utilisation of production resources on the shop floor are expected to be maximised by the process due to a dynamic market environment. This paper presents a recent work by the authors on the concept of using a computational grid to achieve a breakthrough in its performance under conditions of finite capacity. The proposed system resolves capacity constraints by applying a simple heuristic called longest tail first rule, which is proved to minimise the total lead time, to each distributed cluster obviating the need for any rescheduling procedures. Implementation of this concept in a distributed database environment and its performance analysis are described. The experimental results suggest that the proposed finite capacitated MRP process has desirable characteristics in terms of processing time with a deep bill of material as in current supply chain practice.Lee HG, 2007, INT J ADV MANUF TECH, V35, P309, DOI 10.1007/s00170-006-0718-9LEE HY, 2007, THESIS SEOUL NATL USTEFANO MD, 2005, DISTRIBUTED DATA MANKrauter K, 2002, SOFTWARE PRACT EXPER, V32, P135, DOI 10.1002/spe.432Nagendra PB, 2001, INT J PROD RES, V39, P1603, DOI 10.1080/00207540010023600Korpela E, 2001, COMPUT SCI ENG, V3, P78, DOI 10.1109/5992.895191GOUX JP, 2001, CLUSTER COMPUT, V4, P63*SAP AG, 2001, AP215 SUPPL NETW PLAMILLER M, 2001, DISCOVERING P2PPandey PC, 2000, PROD PLAN CONTROL, V11, P113Taal M, 1997, PROD PLAN CONTROL, V8, P245HEEMSBERGEN BL, 1994, PROD PLAN CONTROL, V5, P381SUM CC, 1993, DECISION SCI, V24, P739COYLE JC, 1992, MANAGEMENT BUSINESSCORKILL DD, 1991, AI EXPERT, V6, P40MINIFIE JR, 1986, PRODUCTION INVENTORY, V27, P111MELNYK SA, 1985, INT J PROD RES, V23, P253ALLEN JR, 1984, SUPERCOMPUTERS DESIG, P186HASTINGS NAJ, 1982, J OPER RES SOC, V33, P1021ERMAN LD, 1980, COMPUT SURV, V12, P213AMDAHL GM, 1967, P AFIPS C REST VA, P483

An XML-based process definition language for integrated process management

Business processes are increasingly recognized as important corporate assets that need to be managed throughout their lifecycle. Specially, interests in supply chain management and virtual enterprises require a new paradigm that provides lifecycle support for business processes. Integrated Process Management (IPM) has been proposed as a business process management paradigm that aims at integrating processes using eXtensible Markup Language (XML) and supporting design, analysis, automation, and management of business process knowledge. This paper introduces IPM-PDL, an XML-based process definition language for IPM. Process definitions and related data are integrated using XML which will be translated to a colored Petri Net. Various analysis and simulation can be performed to check the validity of a new process and estimate its performance. The paper also introduces ProcessWare, a prototype system for IPM-process definition language (PDL), along with an extended example which will demonstrate how IPM can effectively manage business processes throughout their lifecycle ranging from process modeling to process knowledge management.close182

Comprehensive Analysis of Cold-Cracking Ratio for Flux-Cored Arc Steel Welds Using Y- and y-Grooves

This study investigates various factors that influence the cold-cracking ratio (CCR) of flux-cored arc welds through Y- and y-groove tests. Factors affecting the CCR include the alloy component, diffusible hydrogen content, microstructure, hardness, and groove shape. In weld metals (WMs; WM375-R and WM375-B) of a low-strength grade, the diffusible hydrogen content has a more significant effect on the CCR than the carbon equivalent (Ceq) and microstructure. However, the combined effects of the microstructure and diffusible hydrogen content on the CCR are important in high-strength-grade WM. The CCR of the WM increased upon increasing Ceq and the strength grade because hard martensite and bainite microstructures were formed. Moreover, y-groove testing of the 500 MPa grade WM revealed a more significant CCR than that of the 375 MPa grade WM. Therefore, in high-strength-grade WMs, it is necessary to select the groove shape based on the morphology in the real welds