Search results for "Crypt"
showing 10 items of 1111 documents
Key Influencing Factors in Early-Stage Hardware Startups: A Trilateral Model of Speed, Resource, and Quality
2020
Hardware startups, i.e., wearable devices, robotics, and Internet of Things, are a significant sector of technology startups, in which software development is relevant and needed. Compared to pure software startups, hardware development in startup contexts lacks a systematic approach and guidelines. This chapter describes an empirical model that captures common elements in product development approaches among many hardware startups. Grounded from insights of 18 active hardware startups, we constructed a trilateral model of resource, speed, and quality in early-stage product development. For startups with relevant contexts, the work suggests the preparation of internal, external resources, a…
Design of Hierarchical Architectures in Metal–Oganic Frameworks for Catalysis and Adsorption
2020
A key factor to improve the performance of metal–organic frameworks (MOFs) is the design and synthesis of hierarchical interconnected porosity at different length scales. The presence of secondary ...
Self-assembly and magnetic properties of a double-propeller octanuclear copper(II) complex with a meso-helicate-type metallacryptand core.
2004
An octanuclear copper(II) complex possessing a dimer-of-tetramers structure self-assembles from a binuclear oxamatocopper(II) metallacryptand of the meso-helicate type; its magnetic behaviour is consistent with its unique double-propeller molecular topology. Pardo Marín, Emilio José, Emilio.Pardo@uv.es ; Julve Olcina, Miguel, Miguel.Julve@uv.es ; Lloret Pastor, Francisco, Francisco.Lloret@uv.es ; Ruiz Garcia, Rafael, Rafael.Ruiz@uv.es
A multistage heuristic for storage and retrieval problems in a warehouse with random storage
2017
The warehouse is one of the essential components of logistics and supply chains. The efficiency of the whole chain is affected by the performance of warehouse operations and, more particularly, the storage and retrieval of goods. This paper considers a storage and retrieval problem in a real warehouse with random storage and different types of forklifts, depending on the locations they can access. The problem deals with selecting locations to store/retrieve a predefined set of pallets, assigning an adequately skilled forklift to each operation and determining the order in which each forklift will perform its operations so that the total employed time is minimized. The problem is solved heur…
A biased random-key genetic algorithm for the time-invariant berth allocation and quay crane assignment problem
2017
We address Berth Allocation and Quay Crane Assignment Problems in a heuristic wayWe propose a Biased Random-Key Genetic Algorithm for BACAP and its extension BACASPSolutions of the Genetic Algorithm are improved by a Local SearchThe complete procedure obtains high-quality solutions for large instances Maritime transportation plays a crucial role in the international economy. Port container terminals around the world compete to attract more traffic and are forced to offer better quality of service. This entails reducing operating costs and vessel service times. In doing so, one of the most important problems they face is the Berth Allocation and quay Crane Assignment Problem (BACAP). This pr…
On Equivalent Random Traffic method extension
2011
The key result of the paper is the Equivalent Random Traffic (ERT) method extension for estimation of the throughput for schemes with traffic splitting. The excellent accuracy (relative error is less than 1%) is shown in numerical example. A numerical algorithm is given — how to estimate the throughput for schemes at traffic splitting and merging. The paper also contains new Erlang-B formula algorithm for non-integer number of channels based on parabolic approximation.
A Simple Metaheuristic for the FleetSize and Mix Problem with TimeWindows
2017
This paper presents a powerful new single-parameter metaheuristic to solve the Fleet Size and Mix Vehicle Routing Problem with Time Windows. The key idea of the new metaheuristic is to perform a random number of random-sized jumps in random order through four well-known local search operators. Computational testing on the 600 large-scale benchmarks of Bräysy et al. (Expert Syst Appl 36(4):8460–8475, 2009) show that the new metaheuristic outperforms previous best approaches, finding 533 new best-known solutions. Despite the significant number of random components, it is demonstrated that the variance of the results is rather low. Moreover, the suggested metaheuristic is shown to scale almost…
A contribution on the optimization strategies based on moving least squares approximation for sheet metal forming design
2012
Computer-aided procedures to design and optimize forming processes are, nowadays, crucial research topics since industrial interest in costs and times reduction is always increasing. Many researchers have faced this research challenge with various approaches. Response surface methods (RSM) are probably the most known approaches since they proved their effectiveness in the recent years. With a peculiar attention to sheet metal forming process design, RSM should offer the possibility to reduce the number of numerical simulations which in many cases means to reduce design times and complexity. Actually, the number of direct problems (FEM simulations) to be solved in order to reach good functio…
The distributed assembly permutation flowshop scheduling problem
2013
Nowadays, improving the management of complex supply chains is a key to become competitive in the twenty-first century global market. Supply chains are composed of multi-plant facilities that must be coordinated and synchronised to cut waste and lead times. This paper proposes a Distributed Assembly Permutation Flowshop Scheduling Problem (DAPFSP) with two stages to model and study complex supply chains. This problem is a generalisation of the Distributed Permutation Flowshop Scheduling Problem (DPFSP). The first stage of the DAPFSP is composed of f identical production factories. Each one is a flowshop that produces jobs to be assembled into final products in a second assembly stage. The o…
Introduction to the Pontryagin Maximum Principle for Quantum Optimal Control
2021
Optimal Control Theory is a powerful mathematical tool, which has known a rapid development since the 1950s, mainly for engineering applications. More recently, it has become a widely used method to improve process performance in quantum technologies by means of highly efficient control of quantum dynamics. This tutorial aims at providing an introduction to key concepts of optimal control theory which is accessible to physicists and engineers working in quantum control or in related fields. The different mathematical results are introduced intuitively, before being rigorously stated. This tutorial describes modern aspects of optimal control theory, with a particular focus on the Pontryagin …