Designer Solid Shims for Assembly of Advanced Carbon Composite Pre-preg based Aircraft Structures

Author(s):  
Sanjay Kumar ◽  
P. Selvaraj

A modern combat aircraft uses considerable amount of advanced composite material in structure build for better flight performance, stealth requirement and higher payload. Combat aircrafts made using composite structure require large numbers of custom shims of various thickness and shapes throughout interface surface, which are presently prepared by suit on assembly process to fill gaps measured between sub-structure parts and skin. The scope of study is four plus generation combat aircraft like Indian Light combat aircraft. These gaps arise due to composite raw material characteristics, mould tool and manufacturing process which results in geometry variation. This research has focussed the delta wing integral fuel tank composite structure. However, these research findings can be applied in other wing shapes made by composite part within the scope. The shims, whether liquid or solid, are necessary to eliminate gaps, maintain structural performance and minimize pull-down forces required to bring the aircraft into engineering nominal configuration for aerodynamic efficiency. Customized shims amount to significant delays in production with much of the time being spent in the critical path of the aircraft assembly. In this research work, we present an alternative strategy for the use of designer solid shim, based on redesign of lay-up moulding tool (female type) and shims manufacturing with change in existing manufacturing value stream. The experimented method has reduced the manufacturing cost of wing assembly, shorten the shimming process cycle and improve the assembly efficiency, product quality and performance.

Author(s):  
Reeta Yadav

Employee’s perception regarding fairness in the organization is termed as organizational justice. The objective of this paper is to study the antecedents and consequences of organizational justice on the basis of earlier relevant studies from the period ranging from 1964 to 2015. Previous research identified employee participation, communication, justice climate as the antecedents and trust, job satisfaction, commitment, turnover intentions, organizational citizenship behavior and performance as the consequences of organizational justice. Finding reveals the gaps existing in the literature and gives suggestions for future research work.


Author(s):  
Krzysztof Nadolny ◽  
Wojciech Kapłonek ◽  
Marzena Sutowska ◽  
Paweł Sutowski ◽  
Piotr Myśliński ◽  
...  

AbstractRaw pine wood processing and especially its mechanical processing constitute a significant share among technological operations leading to obtaining a finished product. Stable implementation of machining operations, ensuring long-term repeatable processing results depends on many factors, such as quality and invariability of raw material, technical condition of technological equipment, adopted parameters of work, qualifications and experience of operators, as well as preparation and properties of the machining tools used. It seems that the greatest potential in the search for opportunities to increase the efficiency of machining operations has the modification of machining tools used in it. This paper presents the results of research work aimed at determining how the life of cutting tools used in planing operations of wet pine wood is affected by the application of chromium aluminum nitride (AlCrN) coating to planar industrial planing knives in the process of physical vapour deposition. For this purpose operational tests were carried out under production conditions in a medium-sized wood processing company. The study compares the effective working time, rounding radius, the profile along the knife (size of worn edge displacement, wear area of the cutting edge), selected texture parameters of the planar industrial planing knife rake face and visual analyses of cutting edge condition of AlCrN-coated planar knives and unmodified ones. The obtained experimental results showed the possibility of increasing the life of AlCrN-coated knives up to 154% compared to the results obtained with uncoated ones. The proposed modification of the operational features of the knives does not involve any changes in the technological process of planing, does not require any interference with the machining station nor its parameters, therefore enabling rapid and easy implementation into industrial practice.


Author(s):  
R C Segundo ◽  
P R English ◽  
G Burgess ◽  
S A Edwards ◽  
O MacPherson ◽  
...  

The role of stockmanship in relation to the wellbeing of farm animals has been emphasised in the UK Codes of Recommendations for the Welfare of Farm Livestock (MAFF, 1983). Moreover, previous research work has demonstrated important effects of good and bad stockmanship not only on welfare but also on growth, lactational and reproductive performance of pigs and other farm livestock (Hemsworth et al, 1987). There is a need, therefore, to establish the factors which motivate and demotivate stockpeople since the degree of job satisfaction is likely to have a considerable influence on the attitude and performance of stockpeople and on their empathy with the animals in their care. With this objective in mind, a questionnaire was designed to investigate the aspects which could have an influence on the job satisfaction of the stockpeople involved in pig production.


2015 ◽  
Vol 244 ◽  
pp. 121-129
Author(s):  
Marian Peciar ◽  
Roman Fekete ◽  
Peter Peciar

This article deals with the presentation of modern applications for processing powdered, primarily hazardous, waste to an agglomeration form appropriate for subsequent processing by classical methods, for example in the construction, automotive and consumer goods industries. The aim of the research work was to set appropriate operating conditions in order to appreciate currently non-processable wastes resulting from the intensive production of often extremely expensive materials. Technologies which enable returning powder waste back into the primary production cycle were developed and experimentally tested, thus saving raw material resources. When necessary for the fixing of fine airborne particles with a problematic compacting curve (hard to compress, repulsive due to the surface charge) extrusion processes using a patented technology enabling controlled modification of shear forces in the extrusion zone were successfully applied. A new type of axial extruder allows the elimination of the liquid phase and as a result prevents the clogging of the extrusion chamber. In the case of need for granulation of sensitive materials (for example pharmaceuticals not allowing the addition of any kind of agglomerating fluid or reacting strongly in the contact of the two phases), a process of compaction between rolls with different profiled surface was successfully applied. The developed high technologies and the resulting products thus represent a major contribution to environmental protection in the context of not only the work but also the communal environment.


Author(s):  
Barbara Widera

The paper addresses the topic of nature-based solutions applied in the architectural and urban design. These ideas are analyzed in the context of the opportunities they create for the humanity in terms of the sustainable growth and environmental protection. Nature-based solutions are inherently taken from nature. The first part of the paper presents their tremendous potential to be energy and resource-efficient, and resilient to change. In the second part of the research particular concepts driven from nature (copied form nature or inspired by nature) proposed for the buildings and cities are described and evaluated. The author discusses their functional usefulness, spatial appropriateness, adaptation to local conditions, end-user comfort, environmental benefits and the possibility of duplication. Nature-based solutions applied in urban planning can make cities more climate resilient and contribute to ecosystems restoration. The paper describes how sustainable urbanization can stimulate economic growth, make cities more attractive and enhance well-being of the inhabitants. It is also explained how particular buildings can benefit from the concepts driven from nature e.g. by increasing their energy efficiency and performance in terms of raw material consumption. In purpose to properly response to the climate challenge, humanity has to establish a new kind of partnership with nature. Using nature-based solutions should be considered as an important part of this approach. The concepts presented in this paper show some of the most promising options, such as integration of living systems with built systems and innovative combinations of soft and hard engineering. In conclusion some of the most promising nature-based solutions for climate resilient buildings and cities are indicated


Author(s):  
W Wu ◽  
S S Rao

The quality and performance of any mechanical system are greatly influenced by the GD&T (geometric dimensioning and tolerancing) used in its design. A proper consideration of the various types of tolerances associated with different components could not only satisfy the assembly requirements, but also minimize the manufacturing cost. To satisfy the design and functional specifications, one has to know how various tolerance patterns affect the manufacturability and assemblability of the designed parts. Therefore, a thorough understanding of how different forms of mechanical tolerances interact with each other becomes a must for designers and manufacturers. The effects of form, orientation, and position tolerances on the kinematic features and dimensions of mechanical systems are analysed using a new approach, based on fuzzy logic, in this article. In this approach, the α-cut method is used with the mechanical tolerances concerned as intervals. The proposed approach represents a more natural and realistic way of dealing with uncertain properties like geometric dimensions. A typical mechanical assembly system involving form, orientation, and position tolerances is used as an illustrative example. As the fuzzy approach leads to systems of non-linear interval equations, a modified Newton-Raphson method is developed for the solution of these equations. The current approach is found to be effective, simple, and accurate and can be extended to the analysis and synthesis of any uncertain mechanical system where the probability distribution functions of the uncertain parameters are unknown.


Author(s):  
KARPAKAVALLI MEENAKSHISUNDARAM ◽  
PRAKASH GOVINDARAJ ◽  
SIVASUBRAMANIAM P. ◽  
RANJITHKUMAR DHANARAJ ◽  
MOHAN SELLAPPAN

Objective: Algae is the undisputed treasures of the sea and are a valuable raw material, providing unlimited opportunities for new drug discoveries. Marine algal products are in demand in the international market in the form of standardized algal extracts or semi-finished products. Methods: Aqueous and methanolic extracts of Oedogonium globosum and Oedogonium intermedium species were obtained maceration and hot percolation. The active principles from O. intermedium were isolated, purified by column chromatography, and characterized by spectral studies IR, λmax, 1HNMR and MS. The extracts of Oedogonium species were screened for their anti-microbial effects, acute dermal irritation and wound-healing activity studies. Results: Comparing to Oedogonium intermedium (45 %, 90 %, 87 %), very low extractive yields were obtained for Oedogonium globosum (10.80 %, 37 %, 28 %). At phytochemical screening, Terpenoids, Flavanoids and, Glycans were found to be present in a significant amount and upon their isolation, it was found that a collection of fractions from cold extract with Rf value in the range 0.32-0.34 as Glycans and those from the hot extract with 0.40-0.72 as Flavanoids and those from methanolic extracts with 0.23, 0.44 and 0.71 as for Terpenoids. Anti-bacterial study revealed out the fact of Oedogonium species could give higher inhibition to gram-positive than for gram-negative bacteria at (10 μg/10μl/disc) concentration. No symptoms of systemic toxicity and mortality were observed. Silver sulfadiazine, more potent in wound closure, the effect of methanolic extracts of O. intermedium (87 %) was almost at par to the standard (95 %) in action and significantly greater than O. globosum (72 %, P<0.05). Conclusion: Admittedly, Oedogonium type algal species can be known as medicinal algae with a plethora of a wide range of pharmacological activities. Thus, this research work may be considered further for extensive innovative discoveries of new lead molecules and any other pharmacological activities, in the future.


2021 ◽  
Vol 24 (2) ◽  
pp. 198-230
Author(s):  
Bharati Singh

This paper presents a bibliometric analysis of relevant publications in the field of behavioral finance and behavioral accounting. The analysis shows that the emerging themes of research in recent years in behavioral finance is on investors’ sentiment, social media, investors’ attention, and financial literacy. In the field of behavioral accounting, biases such as  overconfidence, framing effects or cognitive constraints on information processing, have been explored in greater detail. Other than cognitive biases, this field includes studies such as behavioral tax, organizational ecology, and performance evaluative style of organization, among others. Interestingly, our analysis suggests that research in behavioral accounting is comparatively underdeveloped than research in behavioral finance. This bibliometric analysis has been extended by network analysis using, “Visualization of similarities, (VOS) viewer” software. Using the themes generated here the direction for future scope of research work has been discussed.


Author(s):  
Amit Agrawal

The Supply Chain Improvement (SCO) project is being introduced by KNPC, which recognises the major business advantages of improved hydrocarbon supply chain efficiency. The objectives of this work is to strengthen, optimise, and integrate supply scheduling and processes not just at stage of enterprise, but also throughout the entire KNPC framework. This is expected to lead to an improvement in the company's bottom line and facilitate the management of business operations at the highest level of efficiency, agility and profitability. In ever changing market conditions and globally competitiveness, it is necessary that raw material supply storage and product delivery were carried out at the lowest possible time and efficiency. Otherwise export oriented refinery like KNPC cannot remain in business with profit. KNPC has therefore embarked on ambitious multi-year operational excellence programs aimed at enhancing its operations and business processes that include short / mid-term planning, scheduling, accounting for growth, inventory management, and performance management. The aim is to achieve top-quartile financial results by accessing new value streams, encapsulating business processes of best practice and motivating employees of businesses to work in a collaborative atmosphere within the global and cross-functional business cycle to make smarter, quicker and more competitive choices.


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