1,721,108 research outputs found
Innovative policies for the AS/RS design and management
No full textAutomated Storage/Retrieval Systems (AS/RS) are storage systems capable of providing random access to all stored items (Sarker
and Babu,1995). AS/RSs are being widely used in the logistics industry (Van den Berg, 2000). Major advantages of AS/RS include
high throughput, efficient use of space, high reliability and improvement of safety (Rosenblatt et al., 1993). However, economic
factors, such as initial high investment, inflexible layout and fixed storage capacity, force to carefully evaluate system structures (e.g.
layout and size of the racks, S/R mechanism, number of the spans and of the levels) and operational policies (e.g. allocation of
storage cells and scheduling of the tasks).
The performance of an Automated Storage/Retrieval System depends on the storage rack dimension, on the number of cranes and
aisles, and on the applied control policies such as the dwell point position, the material clustering, etc.
The dwell point position of crane is the location where the stacker lies when it is inactive. Different strategies about dwell point result
in significant gaps in term of performance (e.g. throughput and costs).
The presented research deals with the optimal dwell point evaluation considering a large set of conditions, both concerning the
physical AS/RS configuration (e.g. number of spans, number of levels, etc.) and the characteristics of the requested mission profile
(in terms of inter-mission time and of dual or single command). In this paper, results dealing with the random storage assignment are
presented.
Considering different dwell point strategies, applied to different AS/RS configuration (in terms of number of spans, number of
levels, statistical distribution of the requested missions, etc.) a model supported by a software platform has been developed. For each
instance 1000 runs have been executed and the following parameters have been evaluated:
- travel time: the time spent by a stacker crane to complete a mission (storage/retrieval);
- distance traveled: the distance traveled by a stacker crane to complete a mission (storage/retrieval);
- idle time: the time that a stacker crane lies in its position, waiting for a requested mission (depending the position on the used
policy);
- waiting time: the time that a loaded unit must wait for being “served” (stored and/or retrieved) because the stacker crane is
employed by another request
Structural constraints for kinematic modeling: the Tyrrhenian Pleistocene extension.
No full textThe Tyrrhenian margin of the Apennine chain
(TMAC) experienced widespread extensional tectonics
characterized by volcanism and the formation of several marine and intermontane troughs and basins in
Pleistocene times. The Campania Plain is part of this
extensional system, which encompasses an area from
the southern Tuscany to the northern margin of Calabria. Extensional tectonics affecting these continental
areas is likely to be related with the final stages of the
opening of the southern Tyrrehnian Sea, which developed since Middle Tortonian times. This work present a
quantitative kinematic model to explain the relationships
between extension in the Tyrrhenian Sea, basin formation
in the TMAC, migration of the Apenninic arcs, and geotectonic setting of volcanism. A synthesis of the volcanic,
structural and geophysical data available in literature
coupled with a detailed morpho-tectonic analysis of the
study areas was used in a computer-aided reconstruction
techniques based on interactive modelling of rigid blocks
rotations
The Customers’ Perception of Primary Packaging: a Comparison between Italian and Swedish Situations
No full textThe protection and containment of the product are considered the main roles of packaging. During the last decades, the function of packaging has evolved: it also covers a marketing role and it is something for insuring the product and ease of use to the customers.
One question of immediate interest is how packaging should be designed to be associated with high quality from a customer perspective [1].
The authors base their research on Kano’s theory of attractive quality [2], with a study that reproduces the empirical investigation done by Löfgren and Witell in 2005 in Sweden [1], in order to increase the knowledge about the role of packaging in the perception of quality.
Löfgren and Witell’s work investigated how 24 quality attributes of packages are perceived by customers, mailing a questionnaire to 1500 randomly chosen Swedes and asking them about their experience of packaging in everyday commodities [1]. The authors of this paper want to reproduce the same empirical investigation in Italy, submitting the questionnaire to Italian customers.
This paper has a twofold purpose: the first is to compare two realities, Swedish and Italian customers’ perception, and to underline both the similarities and the differences between them. The second intent concerns the finding of potential developments to increase customer satisfaction and to improve some features linked with packaging, such as environmental aspects and ease of use.
The results show that Italian customers are mainly interested in some packaging attributes, such as protection and ergonomics. Italian users also show interest in packaging made with recyclable materials. Comparing Italian and Swedish customers’ perception, there are some attributes considered important by both (e.g. protection, expiry date and product leakage), but also several differences regarding resealability, the use of recyclable materials and product quantity in packaging
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
The important role of packaging in the Operation Management
No full textThe chapter focuses on the analysis of the impact of packaging in Operations Management
(OM) along the whole supply chain. The product packaging system (i.e. primary, secondary
and tertiary packages and accessories) is highly relevant in the supply chain and its importance
is growing because of the necessity to minimize costs, reduce the environmental impact
and also due to the development of web operations (i.e. electronic commerce).
A typical supply chain is an end-to-end process with the main purpose of production, transportation,
and distribution of products. It is relative to the products’ movements normally
from the supplier to the manufacturer, distributor, retailer and finally the end consumer. All
products moved are contained in packages and for this reason the analysis of the physical
logistics flows and the role of packaging is a very important issue for the definition and design
of manufacturing processes, improvement of layout and increase in companies’ efficiency.
In recent years, companies have started to consider packaging as a critical issue. It is necessary
to analyse the packages’ characteristics (e.g. shape, materials, transport, etc.) in order to
improve the performance of companies and minimize their costs. Packaging concerns all activities
of a company: from the purchasing of raw materials to the production and sale of
finished products, and during transport and distribution.
In order to manage the activities directly linked with the manufacturing of products (and
consequently with the packaging system), the OM discipline is defined. It is responsible for
collecting various inputs and converting them into desired outputs through operations [1].
Recently, more and more companies have started to use web operations. Electronic commerce
(e-commerce) is the most promising application of information technology witnessedin recent years. It is revolutionising supply chain management and has enormous potential
for manufacturing, retail and service operations. The role of packaging changes with the increase
in the use of e-commerce: from the traditional “shop window” it has become a means
of information and containment of products.
The purpose of the chapter is to briefly describe a model of OM discipline usable to highlight
the role of packaging along the supply chain, describing different implications of an
efficient product packaging system for successful management of operations. Particular attention
is paid to the role of product packaging in modern web operations.
The chapter is organised as follows: Section 2 presents a brief description of OM in order to
engage the topic of packaging. The packaging logistics system is described in Section 3, before
presenting experimental results of studies dealing with packaging perception by both
companies and customers [2; 3]. Moreover, Section 3 introduces the packaging logistics system
also including the analysis of the role of packaging in OM and a description of a complete
mathematical model for the evaluation of total packaging cost is presented. Section 4
presents background about modern e-commerce and its relationship with OM. Packaging
and e-commerce connected with OM is described in Section 5 and a case study on packaging
e-commerce in operations is analysed in Section 6. Finally, the conclusion and further research
are presented
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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