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This paper empirically examines the hydrodynamic performances of squat submarines under the resistance and wave tests beside numerical investigation of pressure drag reduction techniques. Despite vast information about the operation of the streamlined fluid vessels, there is not much information about the geometries and hydrodynamic behaviors of squat vessels with L/D ratios below four. This study experimentally investigates the impacts of various relative depths and flow inclinations, intending to find drag, heave, and sway forces at the velocities of 0.5, 1.0, 1.5, 2.0, and 2.5-m/s. A one-tenth scaled model of a squat submarine is examined under the resistance and wave train scenarios as... 

This article experimentally investigates the hydrodynamic interaction of a squat submarine operating behind a ship in various wave and resistance tests. A 0.625 m long (one-tenth scale) captive model of a squat submarine is constructed along with a 1.5 m Fridsma ship to perform 47 unique experiments in a 4 × 6 × 400 m3 tank located in a towing tank center. The submarine is a new midget-submersible, of Apam-Napat SMSD type, with an L/D ratio below four. Wave and resistance tests are performed for various 2D relative lengths and depths at short-distance conditions. A wave of 0.1 m height and 1.5 m wavelength is used in the wave tests, and different operational velocities of 0.5, 1.0, and 1.5... 

This research investigates the short-distance hydrodynamic interaction of a squat submarine towed by a marine vessel. A one-tenth scaled captive model of a 0.625-m squat submarine is constructed along with a 1.5-m Fridsma ship to perform 69 unique experiments in a 4 × 6 × 400-m3 water tank located in a towing tank center. The submarine model is a new mini-submersible, Apam-Napat SMSD type, with an L/D ratio below four. The cable is specified, regarding its weight per unit length, using a scaling method introduced in this paper. The submarine-cable-ship system is tested for nine various relative lengths and depths at short-distance conditions. In each case, drag and heave forces are recorded... 

Nowadays, manufacturing enterprises have been faced with a globalized competitive environment. In this fierce condition, Cloud Manufacturing paradigm emerged as a promising concept for competition. It provides effective solutions and tools for manufacturing enterprises to collaborate in globalized market. The revolution that Cloud Manufacturing has created is based on the redefinition of the classic methods to those which are appropriate for todays' modern and globalized manufacturing environments. In parallel with cloud-based revolution, the expansion of internet-based technologies has been started. These technologies previously have been applied in many fields and resulted in... 

The cloud manufacturing paradigm has been known as one of the best solutions for today's competitive manufacturing environments. This paradigm insists on using a manufacturing service oriented approach for fulfilling the manufacturing enterprise resource management by the access to global availability of manufacturing services. The proposed service oriented approach covers a wide area of manufacturing resource management from infrastructures to platforms and applications. However, due to wide global distributions of manufacturing clouds, the service oriented architectures which are designed in the clouds cannot communicate with each other. This is mainly due to concentration of cloud... 

The emergence of the globalization paradigm in manufacturing industry has changed the markets’ circumstances, and accordingly manufacturing systems need to be compatibilized with these situations. There are many solutions to assist manufacturing systems for this purpose. Computerized systems and their related solutions were being the most attractive ones for manufacturing systems in recent decade. Developing such systems and exploiting from the advantages of such solutions requires a consistent foundation. Computer Integrated Manufacturing (CIM) emerged as a philosophy to provide such foundation, and to assist the computerized manufacturing solutions. Despite of the high potentials of the... 

Cloud Manufacturing (CM) as a successful manufacturing business model and a major driver of Industry 4.0 has attracted a lot of attention in recent years. CM idea aims to streamline the on-demand provisioning of manufacturing resources and capabilities as services, providing end-users with flexible and scalable services accessible through global networks. This idea created many opportunities and challenges. One of the critical challenges is resource allocation, which determines who interacts with whom and how in the CM platform. The type of the platform is a determining factor for the selection of the appropriate resource allocation. To analyze the impact of the allocation on the utilities,... 

With unbounding the manufacturing resources and capabilities from shopfloors and being available as on-demand services for everyone who needs, the service allocation problem becomes critical. Despite of private Cloud Manufacturing platforms in which the service allocation problem is an optimization matching problem, in public Cloud Manufacturing platforms the service allocation problem is a matching game between manufacturing providers and consumers. This is a complex form of games that has two sides, one side is the players that has manufacturing resources and capabilities and the other side is the players who want to receives such services. In this paper, we present a matching game model... 

Online manufacturing platforms are spreading in the manufacturing industry in the shade of Cloud Manufacturing systems. The paper manipulates a matching mechanism for public Cloud Manufacturing platforms based on the Intuitionistic Fuzzy Sets Theory, VIKOR method, and Deferred Acceptance algorithm. The VIKOR method provides a rational, scientific, and systematic approach to enable providers and consumers to evaluate the attributes of each other and develop their preference lists. The method is augmented by the Intuitionistic Fuzzy Sets Theory to grasp the high level of vagueness and uncertainty in the process of preference list development. The utilization of Deferred Acceptance algorithm... 

Online manufacturing markets are new emerging types of markets that are spreading in the shade of public Cloud Manufacturing. This paper introduces a public Cloud Manufacturing market and denotes its differences from a private one. Public Cloud Manufacturing enables service-oriented manufacturing models for everyone in society. The prosperity of such market is tied to appropriate matching between providers to consumers. This paper elaborates on a mechanism to prescribe an appropriate allocation between resources and demands in this public market. The mechanism exploits the VIKOR method to develop preference lists for providers and consumers, the method also is augmented by the Intuitionistic... 

Public platforms are one of the most important Cloud Manufacturing modes. Public platforms enable an environment for manufacturers and demanders to freely and directly connect with each other. Exploiting the high potentials of public platforms depends on final matching. This paper has developed a multi-phase matching mechanism for stable and optimal resource allocation in public platform. The proposed mechanism grades the demanders using an intuitionistic fuzzy VIKOR method using three measures of quality, time, and sustainability. Then, the mechanism clusters the demanders based on these three measures; and finally, allocates the clusters using the Deferred Acceptance (DA) algorithm to the... 

Online manufacturing markets are new emerging types of markets that are spreading in the shade of public Cloud Manufacturing. This paper introduces a public Cloud Manufacturing market and denotes its differences from a private one. Public Cloud Manufacturing enables service-oriented manufacturing models for everyone in society. The prosperity of such market is tied to appropriate matching between providers to consumers. This paper elaborates on a mechanism to prescribe an appropriate allocation between resources and demands in this public market. The mechanism exploits the VIKOR method to develop preference lists for providers and consumers, the method also is augmented by the Intuitionistic... 

Fluorine-doped tin oxide (FTO) nano-powders were synthesized by a gel combustion method. To analyse the effect of processing factors and their interactions and to achieve an equation for nano-powder particle size in terms of code factors, D-optimal factorial design was used. Stannous chloride penta-hydride, ammonium fluoride and citric acid were used to synthesize the FTO nano-powders. The structure, morphology and composition of the synthesized powders were characterized by X-ray diffraction, field emission scanning electron microscopy and X-ray photoelectron spectroscopy, respectively. The results revealed the formation of homogenous FTO nano-powders with an average particle size of 20 nm... 

In this paper, a decentralized controller for trajectory tracking of modular and reconfigurable robot manipulators is developed. The proposed control scheme uses joint-torque sensory feedback; also sliding mode control is employed to make both position and velocity tracking errors of robot manipulators globally converging to zero. Proposed scheme also guarantees that all signals in closed-loop systems will be bounded. In contrast to some of prior works in this scheme, each controller uses a smooth law to achieve its purposes. In this method, each controller uses only local information for producing control law hence separated controller can be used to control each module of manipulator and... 

The most important disadvantage of swinging interferometers is that the optical path difference created in them is a nonlinear function of the rotation angle. In this paper, two new swinging interferometers are presented which have good linearity and provide a larger path difference in response to the rotation angle compared to other interferometers. This makes them suitable for applications such as high-resolution spectroscopy, and precision micro and nanopositioning. In one of these two interferometers, the optical path difference is created by rotation of a system composed of four mirrors, and in the other one it is created by rotation of a system consisting of two mirrors. They are not...