Structural analysis of a small volume offshore aquaculture cage system utilizing numerical modeling and scaled physical testing

The global demand for fish products has surpassed the supply available from wild harvest. As this demand continues to increase, the need for ample aquaculture facilities is causing many protective coastal areas, common for fish growing sites, to become highly overloaded creating both environmental and space concerns. Progressive solutions are enabling the development of new sites in the offshore environment. This study evaluated the structural performance of the American Soybean Association International Marketing and U.S. Soybean Export Council\u27s open ocean aquaculture fish cage and mooring design proposed for use in developing countries. The analysis included numerical modeling and physical testing. Dynamic simulations investigated performance of the system when subjected to multiple regular and random waves as well as currents. Physical testing was conducted on a scale model in a wave/tow tank. Motion and load responses were analyzed and compared to predict the cage response for deployment at a variety of potential sites. These results were further used to investigate the reliability of the cage frame through a numerical structural analysis. The analysis showed that the cage will not fail under any of the considered loadings

CSR for retailers' led channel relationships: Evidence from Italian SME manufacturers

This paper analyses the adoption of Corporate Social Responsibility (CSR) policies by small and medium manufacturers which are involved in supplying relationships with large retailers. The purpose of the paper is to examine CSR drivers within large retailers' supply chains. A quantitative empirical research was conducted focusing on the food sector, as a sector in which traceability, supplier’s coordination and control are critical to the supply chain. Data collection was performed through a questionnaire addressed to 89 Italian SME manufacturers to explore the main factors influencing the adoption of CSR and the level of formalization of the related policies. Findings revealed the key role of large retailers for the establishment of a sustainable/ethical supply chain. An attenuation of the hierarchic/conflictual perspective in buyer-seller relationships emerged, with a reduction of margin-compression effects for smaller suppliers as a consequence of power imbalances. A relevant consequence of CSR is a relationship development model in which all the involved subjects can benefit, including smaller partners inside the supply chains

NetPDL: An Extensible XML-Based Language for Packet Header Description

Although several applications need to know the format of network packets to perform their tasks, till now, each application uses its own packet description database. This paper addresses this problem by proposing the NetPDL, an XML-based language for describing packet headers, which has the potential of enabling the realization of a common, application-independent protocol description database that can be shared among several applications. Further, common functionalities related to the protocol database can be implemented in a library, which can be a basic building block for implementing networking applications

SME food suppliers versus large retailers: perspectives in the international supply chains

none3noThe market share of international retail chains substantially increased from the beginning of the nineties. The supplier’s market has been adapted to the evolutions of retailers’ market in terms of modified purchasing processes. The concentration of large food retailers has been much faster than the same process among manufacturers. Due to these changes, the requirements towards food industry suppliers grew in number and quality. Thus it is generally true that the nature of the buyer-supplier relationship in retailing has been undergoing dramatic changes. Important literature has described these emerging relationships as "partnerships" or "strategic alliances," as opposed to the traditional "arm's length" type of associations. But these conditions are likely to change especially in the relationships between small and medium suppliers and large retailers. The paper shows how the relationships between suppliers and retailers are experiencing several important changes, above all at international level. In particular, the analysis is focused on the Italian food SME suppliers related with international large retailers. Considering the focus of this paper, in-depth interviews to 28 Italian food SME suppliers have been conducted in early 2007. Results have been analyzed and compared to the retailers’ point of view, resulting from public reports (such as Annual report, CSR report, etc.) to understand retail companies’ approach to SME suppliers. Considering the main topics of such relations and the selection criteria used by retailers, one of the main results of the analysis is that the unbalance of power in the relation is not necessarily a negative condition, as the growth of SME suppliers is stimulated by an improving attitude to operate with large retailers. Retailers reserve a wide space on their shelves to SME references because they contribute to increase the variety of merchandising and ensure a more tight control on the supply chain (traceability). At the same time, the strong pressure on price and the required organizational qualifications lead to a selection process, in which smaller manufacturers seem to be the more vulnerable actors.openC. Pepe; F. Musso; M. RissoC., Pepe; Musso, Fabio; M., Riss

Modeling Complex Packet Filters with Finite State Automata

Designing an efficient and scalable packet filter for modern computer networks becomes each day more challenging: faster link speeds, the steady increase in the number of encapsulation rules (e.g., tunneling) and the necessity to precisely isolate a given subset of traffic cause filtering expressions to become more complex than in the past. Most of current packet filtering mechanisms cannot deal with those requirements because their optimization algorithms either cannot scale with the increased size of the filtering code, or exploit simple domain-specific optimizations that cannot guarantee to operate properly in case of complex filters. This paper presents pFSA, a new model that transforms packet filters into Finite State Automata and guarantees the optimal number of checks on the packet, also in case of multiple filters composition, hence enabling efficiency and scalability without sacrificing filtering computation time

CrownLabs - A Collaborative Environment to Deliver Remote Computing Laboratories

The coronavirus pandemic hit the entire education sector hard. All students were sent home and lectures started to be delivered through video-conferencing systems. CrownLabs is an open-source project providing an answer to the problem of delivering remote computing laboratories. Simplicity is one of its main characteristics, requiring nothing but a simple web browser to interact with the system and being all heavyweight computations performed at the university premises. Cooperation and mentoring are also encouraged through parallel access to the same remote desktop. The entire system is built up using components from the Kubernetes ecosystem, to replicate a "cloud grade" infrastructure, coupled with custom software implementing the core business logic. To this end, most of the complexity has been delegated to the infrastructure, to speed up the development process and reduce the maintenance burden. An extensive evaluation has been performed in both real and simulated scenarios to validate the overall performance: the results are encouraging, as well as the feedback from the early adopters of the system

Moving Applications from the Host to the Network: Experiences, Challenges and Findings

Some recent works propose to extend network devices (e.g., routers) with the possibility to execute additional user-provisioned software operating on the data-plane. This enables network devices to be enriched with new functionalities, potentially decided at run-time directly by the end users. This paper focuses on one of such programmable routing platform and presents our experience in developing new software (namely, a parental control service) in that environment. In addition, we describe also two extensions to our platform that were needed to accommodate the necessity of our applications

On the Efficiency of Packet Telephony

This paper presents a study on the efficiency of packet switching in providing toll quality telephone services. Packet switching is appealing for the implementation of a commercial telephone network because it features lower cost and higher manageability than circuit switching, and enables integration of real-time and non real-time services. This work compares the real-time efficiency of packet switching and circuit switching, i.e., the volume of voice traffic being guaranteed deterministic quality related to the amount of network resources used. For this purpose, we developed a call level simulator which allows a general topology network to be studied. The simulator performs call admission control according to the availability of the resources required to provide a deterministic delay bound for each call. Statistical data on accepted and rejected calls are the simulation output. Results show that packet size - possibly constrained by the protocol in use - is a key factor in determining the real-time efficiency. The packet size which maximizes real-time efficiency is devised analytically

Some Controversial Opinions on Software-Defined Data Plane Services

Several recent proposals, namely Software Defined Networks (SDN), Network Functions Virtualization (NFV) and Network Service Chaining (NSC), aim to transform the network into a programmable platform, focusing respectively on the control plane (SDN) and on the data plane (NFV/NSC). This paper sits on the same line of the NFV/NSC proposals but with a more long-term horizon, and it presents its considerations on some controversial aspects that arise when considering the programmability of the data plane. Particularly, this paper discusses the relevance of data plane vs control plane services, the importance of the hardware platform, and the necessity to standardize northbound and southbound interfaces in future software-defined data plane service