A General Simulation Framework for Supply Chain Modeling: State of the Art and Case Study

Nowadays there is a large availability of discrete event simulation software that can be easily used in different domains: from industry to supply chain, from healthcare to business management, from training to complex systems design. Simulation engines of commercial discrete event simulation software use specific rules and logics for simulation time and events management. Difficulties and limitations come up when commercial discrete event simulation software are used for modeling complex real world-systems (i.e. supply chains, industrial plants). The objective of this paper is twofold: first a state of the art on commercial discrete event simulation software and an overview on discrete event simulation models development by using general purpose programming languages are presented; then a Supply Chain Order Performance Simulator (SCOPS, developed in C++) for investigating the inventory management problem along the supply chain under different supply chain scenarios is proposed to readers.Comment: International Journal of Computer Science Issues online at http://ijcsi.org/articles/A-General-Simulation-Framework-for-Supply-Chain-Modeling-State-of-the-Art-and-Case-Study.ph

HC-290 (Propane) Vaporisation Inside a Brazed Plate Heat Exchanger

This paper presents the heat transfer coefficients measured during HC-290 (Propane) vaporisation inside a brazed plate heat exchanger: the effects of heat flux, saturation temperature (pressure) and outlet conditions are investigated. The heat transfer coefficients show weak sensitivity to saturation temperature (pressure) and great sensitivity to heat flux and outlet conditions. The saturated boiling experimental heat transfer coefficients are compared with two well-known equations for nucleate boiling (Cooper (1984) and Gorenflo (1993)). The mean absolute percentage deviation between experimental and calculated heat transfer coefficients is 26.9% and 16.6% for Cooper (1984) and Gorenflo (1993) equation respectively. The heat transfer measurement has been complemented with IR thermography in order to quantify the portion of the heat transfer surface affected by vapour super-heating

Extended stellar kinematics of elliptical galaxies in the Fornax cluster

We present extended stellar kinematics for a sample of 13 elliptical galaxies in the Fornax cluster. Major-axis velocity dispersion profiles (VDPs) and rotation curves (RCs) are given for 12 of the galaxies. A major feature of this data is the spatial extension: for 8 galaxies the data extends beyond 1 R_e, and for 5 it extends beyond 2 R_e. Compared to the previously available data, this corresponds to an increase in spatial coverage by a factor from 1 to 5. Five of the ellipticals in the sample turn out to be rotationally-supported systems, having positive rotation parameter log (V/sigma)*. One of these five, and another 3 galaxies from the remaining sample, display evidence for bar-like kinematics. The data indicate that the true number of `dynamically hot' stellar systems, is much lower than previously thought: of the Es in the present sample only 1/4 are confirmed as `pressure-supported' systems. The data reveal a host of individual peculiarities, like: wiggles, strong gradients, and asymmetries in the rotation curve and/or in the velocity dispersion profile, thus showing that the presence of kinematically distinct components and/or triaxiality is a common characteristic of this class of object.Comment: 27 pages, includes 15 eps figures. Accepted for publication in A&A Sup

design and simulation of two robotic systems for automatic artichoke harvesting

The target of this research project was a feasibility study for the development of a robot for automatic or semi-automatic artichoke harvesting. During this project, different solutions for the mechanical parts of the machine, its control system and the harvesting tools were investigated. Moreover, in cooperation with the department DISPA of University of Catania, different field structures with different kinds of artichoke cultivars were studied and tested. The results of this research could improve artichoke production for preserves industries. As a first step, an investigation on existing machines has been done. From this research, it has been shown that very few machines exist for this purpose. Based also on previous experiences, some proposals for different robotic systems have been done, while the mobile platform itself was developed within another research project. At the current stage, several different configurations of machines and harvesting end-effectors have been designed and simulated using a 3D CAD environment interfaced with Matlab®. Moreover, as support for one of the proposed machines, an artificial vision algorithm has been developed in order to locate the artichokes on the plant, with respect to the robot, using images taken with a standard webcam

Refrigerant R410A Vaporisation Inside a Small Brazed Plate Heat Exchanger

This paper presents the experimental heat transfer coefficients and pressure drop measured during refrigerant R410A vaporisation inside a small brazed plate heat exchanger: the effects of heat flux, refrigerant mass flux, saturation temperature and outlet conditions are investigated. The experimental results are reported in terms of refrigerant side heat transfer coefficients and frictional pressure drop. The heat transfer coefficients show high sensitivity both to heat flux and outlet conditions and weak sensitivity to saturation temperature. The frictional pressure drop shows high sensitivity to refrigerant mass flux and weak sensitivity both to saturation temperature and outlet conditions. The experimental heat transfer coefficients are also compared with two well-known correlations for nucleate pool boiling: a fair agreement is found

Logistics chain responsiveness to war impacts: A case study in North Adriatic Region

The Russian-Ukraine conflict outbreak abruptly interrupted the sea-road intermodal service which provided some metal companies in the Italian region of Friuli Venezia Giulia with semi-finished steel products coming from the Ukrainian port of Mariupol. Those companies were then forced to find an alternative supply source to feed their production system, which entailed the arrival of oceanic vessels with a greater cargo load, but at a lower frequency. Such changes implied significant consequences both on the maritime and the land side and requested the employment of trucks, train and barges to transfer the increased volume of goods. Moreover, those variations generated additional costs for all the involved operators, threating the survivability of the whole supply chain and, thus, of an important share of the regional economy. In this paper, a methodology combining process modelling and quantitative analysis has been applied, first, to gain an in-depth understanding of the case study and then, to suggest modifications to existing policies. Such investigation techniques enabled, on one hand, to identify process bottlenecks and, on the other hand, to examine infrastructural and financial consequences for each considered transport mode. Results revealed the need of adjusting the current strategic vision especially with reference to the development of the infrastructural networks, the introduction of incentive schemes and the availability of skilled people operating in logistics. The proposed lines of action are meant to foster the resilience of the analysed supply chain at economic, environmental and social level

Fibroepithelioma of Pinkus: Solitary tumor or sign of a complex gastrointestinal syndrome

Fibroepithelioma of Pinkus (FEP), which is considered to be an uncommon variant of basal cell carcinoma, has been described in association with other systemic diseases. However, no specific studies are currently available on this subject. The aim of our study was to evaluate the clinical and morphological characteristics of FEP and investigate whether this rare tumor is a single entity or seen in the context of a more complex syndrome. We retrospectively analyzed 49 cases of FEP diagnosed and excised in a single academic institution from 1995 to 2011. The tumors were mainly located on the trunk (77.55%), followed by the lower extremities (12.20%) and the head and neck (10.20%). In 9 of the 49 cases (18%), FEP was associated with gastrointestinal tumors. The abovementioned cases are presented in an attempt to make clinicians more aware of a possible association between FEP and gastrointestinal cancer. Although a possible underlying common genetic background between FEP and gastrointestinal tumors was not provided, our study suggests that patients with FEP should be screened for the occurrence of gastrointestinal tumors

Cisplatin induced toxicity in rat tissues: The protective effect of Lisosan G

The protective effect of a powder of grain (Lisosan G) against cisplatin-induced toxicity in rats was studied. Male rats were fed with Lisosan G before injection of cisplatin and four days later they were killed and blood was collected along with hepatic, renal and testicular tissues. The results showed that cisplatin treatment increased plasma blood urea nitrogen, creatinine and hydrogen peroxide and decreased cytochrome P450 content in renal and hepatic tissues. It also reduced the plasmatic testosterone level and caused a depletion of testicular 17a-progesterone hydroxylase activity. In the group fed with Lisosan G and treated with cisplatin blood urea nitrogen and creatinine returned to the control level indicating a protective effect of Lisosan G. It was also observed that the ones fed with Lisosan G were able to attenuate the decrease in the P450-dependent activities and the activities of antioxidant enzymes as well. Lisosan G protected the testicular 17a-progesterone hydroxylase activity and increased the plasma testosterone level compared to animals treated only with cisplatin. Our results showed a protective effect of Lisosan G against the cisplatin induced toxicity. The protective effect of Lisosan G could be associated mainly with the attenuation of the oxidative stress and the preservation in antioxidant enzymes