Block Construction of Small Ships and Boats Through Use of Developable Panels*

2002 ◽  
Vol 18 (02) ◽  
pp. 65-72
Author(s):  
Rolf Oetter ◽  
Christopher D. Barry ◽  
Bryan Duffty ◽  
Joel Welter

The authors propose a simple method to improve productivity for construction and subsequent outfitting of typical hard-chine boats. This method uses CAD/CAM definition of the structure to manufacture the bottom and sides, decks and bulkheads of the boat as independent panels. The system divides such craft into construction modules by surfaces instead of by blocks as in standard shipbuilding practice. Since all of these panels are developable, an adjustable jigging system supports them essentially horizontally on their rulings. Transverse stiffeners are then welded to the panels. The system and details are optimized for maximum use of downhand welding and weld pacers. This system, however, requires specialized software to develop piece parts and to efficiently derive these modules from the product model. The developable panels can be outfitted with machinery, foundations, piping, wiring and insulation. Bottom and side panels can be tipped up, joined and more outfit installed in stages optimized for lifting and ready access. The deck is built and outfitted inverted, and then joined to the open hull. The bulkhead details and deck framing are also optimized to allow ready outfitting and subsequent joining of the deck as a unit. The easy access to the panels also allows effective, low-cost surface preparation and painting, so this system has benefits for both steel and aluminum construction.

1996 ◽  
Vol 12 (02) ◽  
pp. 99-106
Author(s):  
Kaj Johansson

In a shipbuilding CAD/CAM system a product model is successively built up during the design process, with geometric as well as nongeometric information. In parallel with the design process, the model is further extended with work preparation (in some countries called production engineering) information, e.g., definition of building strategy and definition of the assembly structure. Information needed for part fabrication can be derived from the model, such as drawings, parts lists and information for numerically controlled (NC) equipment. When work preparation definitions are combined with a product model, the information needed for assembly parts lists, assembly drawings, etc. can be derived from the product model instead of being created manually. Use of the product model concept, systems based upon it and procedures implementing it in an organization will allow a reduction of costs and an increase in productivity and competitiveness


Author(s):  
Andreas Liebal ◽  
Heidi Krömker ◽  
Atif Mahboob ◽  
Christian Weber

Abstract Breaking into the consumer market, Virtual Reality (VR) has now penetrated wide areas of the industrial market. Rapidly developing technologies are opening up new application possibilities with low cost and high quality solutions. Although VR has been used exclusively as a marketing tool in companies up to now, it is still being extended to support all areas of the complete product development process. However, this is also accompanied by the difficulty to manage the amount of functionalities and design options associated with VR. Developers of such VR systems must nevertheless maintain an overview of the multitude of technological and content-related possibilities and bring them in line with the requirements of VR customers or VR users. At the same time, VR customers must also have an idea of the technological possibilities and formulate their vision of a VR system as precisely, completely and goal-oriented as possible. In the end, both sides must find a common level of communication in order to record the characteristics of the VR system in the form of a requirement specification or an offer. Factors such as different terminologies and different views about the product development process along with the diverse knowledge about VR functionalities on both sides complicate this process. This article is intended to show the concept for a toolbox that supports the definition of a customer-specific VR solution. This shall exploit the full potential of VR for the customer’s specific product development process in VR. The generic product development process will be studied and the VR application areas will be located. In this regard, a classification of the main components of VR systems is performed. The goal of such a classification is to establish a relationship between the product model (along with product specific properties and relationships) and the VR system components. As the field of VR does not yet have an established set of standardized terms, a definition of all terms in this context can help to improve communication between customer and developer. This article shows how a toolbox for agencies and development departments must be structured so that the VR developer can design, evaluate, calculate and develop a complex VR system in a customer-oriented way. Furthermore, the vision of the toolbox presented in this paper also has the goal that the VR customer can specifically formulate his/her requirements in a customer-specific way that leads to an easier understanding for VR developer and eventually to a VR solution. Finally, the possibility of extension of the presented toolbox structure is discussed to automatically generate specification proposals and suitable technology recommendation based on the problem at hand.


2009 ◽  
Vol 16-19 ◽  
pp. 781-785 ◽  
Author(s):  
Gang Wei Cui ◽  
Ying Xue Yao ◽  
Yu Wang

Virtual assembly based on the virtual reality gives a low-cost and rapid prototyping method for products’ assembly, and tolerances have become a key technique of information integration in CAD/CAM. It will be a new task about how to integrate tolerances into virtual assembly. A toleranced product model based on the virtual reality is constructed for the virtual assembly, and the essential data is saved and managed in database. Model transform interface software is developed, which is a special software that users can get the essential data without any users’ acting. The geometric model of products is constructed in the virtual reality, and the method of getting assembly information, dimensions, and tolerances is proposed. A toleranced product modeling system based on the virtual reality is developed, and the using of tolerances is discussed by an example.


2004 ◽  
Vol 20 (04) ◽  
pp. 221-231
Author(s):  
Rolf Oetter ◽  
Christopher D. Barry ◽  
Lawrence A. DeCan ◽  
Paul F. Sorensen

The power of the integrated product model can be extended well beyond the mere definition of geometry, and this extension offers significant benefits to shipbuilders. The nature of computer-aided design/manufacturing (CAD/CAM) data allows use of arbitrarily extensible linked databases, which can contain any other information that might be useful for manufacture, production engineering, procurement, and even maintenance and operation of the ship throughout its life cycle.


2021 ◽  
Author(s):  
Bo Liu ◽  
Luanying Yang ◽  
Gang Wang ◽  
Sha He ◽  
Xiaobo Wang ◽  
...  

A simple and low-cost electrochemical CEA immunosensor was investigated via the self-polymerization of dopamine and a dithiol compound spacer for the covalent immobilization of antibodies. The designed CEA immunosensor exhibited a linear response and a low detection limit.


2021 ◽  
pp. 1-17
Author(s):  
Daniel Acland

Abstract Benefit-cost analysis (BCA) is typically defined as an implementation of the potential Pareto criterion, which requires inclusion of any impact for which individuals have willingness to pay (WTP). This definition is incompatible with the exclusion of impacts such as rights and distributional concerns, for which individuals do have WTP. I propose a new definition: BCA should include only impacts for which consumer sovereignty should govern. This is because WTP implicitly preserves consumer sovereignty, and is thus only appropriate for ‘sovereignty-warranting’ impacts. I compare the high cost of including non-sovereignty-warranting impacts to the relatively low cost of excluding sovereignty-warranting impacts.


Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 85
Author(s):  
Jorge Lopez-Jimenez ◽  
Nicanor Quijano ◽  
Alain Vande Wouwer

Climate change and the efficient use of freshwater for irrigation pose a challenge for sustainable agriculture. Traditionally, the prediction of agricultural production is carried out through crop-growth models and historical records of the climatic variables. However, one of the main flaws of these models is that they do not consider the variability of the soil throughout the cultivation area. In addition, with the availability of new information sources (i.e., aerial or satellite images) and low-cost meteorological stations, it is convenient that the models incorporate prediction capabilities to enhance the representation of production scenarios. In this work, an agent-based model (ABM) that considers the soil heterogeneity and water exchanges is proposed. Soil heterogeneity is associated to the combination of individual behaviours of uniform portions of land (agents), while water fluxes are related to the topography. Each agent is characterized by an individual dynamic model, which describes the local crop growth. Moreover, this model considers positive and negative effects of water level, i.e., drought and waterlogging, on the biomass production. The development of the global ABM is oriented to the future use of control strategies and optimal irrigation policies. The model is built bottom-up starting with the definition of agents, and the Python environment Mesa is chosen for the implementation. The validation is carried out using three topographic scenarios in Colombia. Results of potential production cases are discussed, and some practical recommendations on the implementation are presented.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ananthamurthy Koteshwara ◽  
Nancy V. Philip ◽  
Jesil Mathew Aranjani ◽  
Raghu Chandrashekhar Hariharapura ◽  
Subrahmanyam Volety Mallikarjuna

AbstractA carefully designed ammonium sulfate precipitation will simplify extraction of proteins and is considered to be a gold standard among various precipitation methods. Therefore, optimization of ammonium sulfate precipitation can be an important functional step in protein purification. The presence of high amounts of ammonium sulphate precludes direct detection of many enzymatically active proteins including reducing sugar assays (e.g. Nelson-Somogyi, Reissig and 3,5-dinitrosalicylic acid methods) for assessing carbohydrases (e.g. laminarinase (β (1–3)-glucanohydrolase), cellulases and chitinases). In this study, a simple method was developed using laminarin infused agarose plate for the direct analysis of the ammonium sulphate precipitates from Streptomyces rimosus AFM-1. The developed method is simple and convenient that can give accurate results even in presence of ammonium sulfate in the crude precipitates. Laminarin is a translucent substrate requiring the use of a stain to visualize the zones of hydrolysis in a plate assay. A very low-cost and locally available fluorescent optical fabric brightener Tinopal CBS-X has been used as a stain to detect the zones of hydrolysis. We also report simple methods to prepare colloidal chitin and cell free supernatant in this manuscript.


Uro ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 39-44
Author(s):  
Mehmet Gürkan Arıkan ◽  
Göktan Altuğ Öz ◽  
Nur Gülce İşkan ◽  
Necdet Süt ◽  
İlkan Yüksel ◽  
...  

There have been few studies reported with conflicting results in the use of neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), redcell-distribution-width (RDW), etc. for predicting prognosis and differential diagnosis of adrenal tumors. The aim of this study is to investigate the role of inflammatory markers through a complete blood count, which is an easy access low-cost method, for the differential diagnosis of adrenocortical adenoma (ACA), adrenocortical carcinoma (ACC), and pheochromocytoma. The data of patients who underwent adrenalectomy between the years of 2010–2020 were retrospectively analyzed. Systemic hematologic inflammatory markers based on a complete blood count such as neutrophil ratio (NR), lymphocyte ratio (LR), NLR, PLR, RDW, mean platelet volume (MPV), and maximum tumor diameter (MTD) were compared between the groups. A statistically significant difference was found between the three groups in terms of PLR, RDW, and MTD. With post-hoc tests, a statistically significant difference was found in PLR and MTD between the ACA and ACC groups. A statistically significant difference was found between the ACA and pheochromocytoma groups in PLR and RDW values. In conclusion, it could be possible to plan a more accurate medical and surgical approach using PLR and RDW, which are easily calculated through an easy access low-cost method such as a complete blood count, together with MTD in the differential diagnosis of ACC, ACA, and pheochromocytoma.


2013 ◽  
Vol 631-632 ◽  
pp. 1335-1341
Author(s):  
Shi Yong ◽  
Wen Tao Liu

In order to meet the needs of enterprises for chamfering complex parts, based on the customization of commercial CAD/CAM software, chamfer programming software is developed. According to user’s machining demands for a part, a chain of edges of a part is extracted from its 3D model. With preprocessing of the chain of edges, the continuity of the chain is estimated, and the start and end point of those edges are automatic obtained. Furthermore, with human-machine dialogue, machining parameters is set by users. By definition of the primary and secondary surfaces of the chain of edges, and interpolation of the edges, the positions of cutter location point and postures of cutter are calculated. Finally the interference of tool path is checked, and tool path is simulated. The software solves the programming problem of chamfering complex parts.


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