Preferred Vehicle Scaling

Author(s):  
Michael L. Jonson

Properly designed and geometrically similar small-scale models can provide insight into component and system performance of large vehicles for a variety of engineering disciplines for a fraction of the cost compared to full scale fabrication and testing. Using the density, specific heat, magnetic permeability of the fluid, the rotation rate, and the size, the author provides non-dimensional performance properties broadly encompassing the hydrodynamic, acoustic, electro-magnetic, thermal, and structural fields. The preferred numbers based on a geometric series as devised by Renard are introduced. The author then provides a method for defining a mean and standard deviation of a size differences from a standard geometric series. In particular, statistics for customary and metric material specifications of sheet metal, square and round stock, electrical wire, fasteners, beams, and pipes are quantified. The study concludes that preferred numbers are best for standard material sizes and scales and suggests potential procedures for improving systems engineering.

Author(s):  
Jure Salobir ◽  
Jože Duhovnik ◽  
Jože Tavčar

AbstractTechnology of 3D printing is opening the possibility for small-scale production in quantities between ten and several hundred pieces. The technology of adding material enables the production of complex and integrated functional concepts in a single-pass process, which consequently potentially reduces the need for assembly operations. Design approaches and manufacturing processing are not mastered well because of a constant stream of new materials and manufacturing options. Well-designed products need to consider attributes of 3D printing as early as the conceptual phase. The cost of the product can be reduced with a systematic research and considering principles for small-scale production. In a cheaper, alternative production process the quality range of products is often lower. It has to be compensated with appropriate construction solutions which are less tolerance-sensitive. Therefore, in order to support the designer, to reduce the costs and design time of the product, a computer program was created to provide the user with an insight into the appropriate 3D printing technology. For simplifying the use, the program is also integrated into the product development process.


2020 ◽  
Vol 3 (1) ◽  
pp. 61
Author(s):  
Kazuhiro Aruga

In this study, two operational methodologies to extract thinned woods were investigated in the Nasunogahara area, Tochigi Prefecture, Japan. Methodology one included manual extraction and light truck transportation. Methodology two included mini-forwarder forwarding and four-ton truck transportation. Furthermore, a newly introduced chipper was investigated. As a result, costs of manual extractions within 10 m and 20 m were JPY942/m3 and JPY1040/m3, respectively. On the other hand, the forwarding cost of the mini-forwarder was JPY499/m3, which was significantly lower than the cost of manual extractions. Transportation costs with light trucks and four-ton trucks were JPY7224/m3 and JPY1298/m3, respectively, with 28 km transportation distances. Chipping operation costs were JPY1036/m3 and JPY1160/m3 with three and two persons, respectively. Finally, the total costs of methodologies one and two from extraction within 20 m to chipping were estimated as JPY9300/m3 and JPY2833/m3, respectively, with 28 km transportation distances and three-person chipping operations (EUR1 = JPY126, as of 12 August 2020).


Author(s):  
Mohammad Istiak Hossain ◽  
Jan I. Markendahl

AbstractSmall-scale commercial rollouts of Cellular-IoT (C-IoT) networks have started globally since last year. However, among the plethora of low power wide area network (LPWAN) technologies, the cost-effectiveness of C-IoT is not certain for IoT service providers, small and greenfield operators. Today, there is no known public framework for the feasibility analysis of IoT communication technologies. Hence, this paper first presents a generic framework to assess the cost structure of cellular and non-cellular LPWAN technologies. Then, we applied the framework in eight deployment scenarios to analyze the prospect of LPWAN technologies like Sigfox, LoRaWAN, NB-IoT, LTE-M, and EC-GSM. We consider the inter-technology interference impact on LoRaWAN and Sigfox scalability. Our results validate that a large rollout with a single technology is not cost-efficient. Also, our analysis suggests the rollout possibility of an IoT communication Technology may not be linear to cost-efficiency.


Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2263
Author(s):  
Mahmood Ebadian ◽  
Shahab Sokhansanj ◽  
David Lee ◽  
Alyssa Klein ◽  
Lawrence Townley-Smith

In this study, an inter-continental agricultural pellet supply chain is modeled, and the production cost and price of agricultural pellets are estimated and compared against the recent cost and price of wood pellets in the global marketplace. The inter-continental supply chain is verified and validated using an integration of an interactive mapping application and a simulation platform. The integrated model is applied to a case study in which agricultural pellets are produced in six locations in Canada and shipped and discharged at the three major ports in Western Europe. The cost of agricultural pellets in the six locations is estimated to be in the range of EUR 92–95/tonne (CAD 138–142/tonne), which is comparable with the recent cost of wood pellets produced in small-scale pellet plants (EUR 99–109/tonne). The average agricultural pellet price shipped from the six plants to the three ports in Western Europe is estimated to be in a range of EUR 183–204 (CAD 274–305/tonne), 29–42% more expensive that the average recent price of wood pellets (EUR 143/tonne) at the same ports. There are several potential areas in the agricultural pellet supply chains that can reduce the pellet production and distribution costs in the mid and long terms, making them affordable supplement to the existing wood pellet markets. Potential economic activities generated by the production of pellets in farm communities can be significant. The generated annual revenue in the biomass logistics system in all six locations is estimated to be about CAD 21.80 million. In addition, the logistics equipment fleet needs 176 local operators with a potential annual income of CAD 2.18 million.


2021 ◽  
pp. 135910532110299
Author(s):  
Terise Broodryk ◽  
Kealagh Robinson

Although anxiety and worry can motivate engagement with COVID-19 preventative behaviours, people may cognitively reframe these unpleasant emotions, restoring wellbeing at the cost of public health behaviours. New Zealand young adults ( n = 278) experiencing nationwide COVID-19 lockdown reported their worry, anxiety, reappraisal and lockdown compliance. Despite high knowledge of lockdown policies, 92.5% of participants reported one or more policy breaches ( M  = 2.74, SD = 1.86). Counter to predictions, no relationships were found between anxiety or worry with reappraisal or lockdown breaches. Findings highlight the importance of targeting young adults in promoting lockdown compliance and offer further insight into the role of emotion during a pandemic.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Loes Ottink ◽  
Marit Hoogendonk ◽  
Christian F. Doeller ◽  
Thea M. Van der Geest ◽  
Richard J. A. Van Wezel

AbstractIn this study, we compared cognitive map formation of small-scale models of city-like environments presented in visual or tactile/haptic modalities. Previous research often addresses only a limited amount of cognitive map aspects. We wanted to combine several of these aspects to elucidate a more complete view. Therefore, we assessed different types of spatial information, and consider egocentric as well as allocentric perspectives. Furthermore, we compared haptic map learning with visual map learning. In total 18 sighted participants (9 in a haptic condition, 9 visuo-haptic) learned three tactile maps of city-like environments. The maps differed in complexity, and had five marked locations associated with unique items. Participants estimated distances between item pairs, rebuilt the map, recalled locations, and navigated two routes, after learning each map. All participants overall performed well on the spatial tasks. Interestingly, only on the complex maps, participants performed worse in the haptic condition than the visuo-haptic, suggesting no distinct advantage of vision on the simple map. These results support ideas of modality-independent representations of space. Although it is less clear on the more complex maps, our findings indicate that participants using only haptic or a combination of haptic and visual information both form a quite accurate cognitive map of a simple tactile city-like map.


2019 ◽  
Vol 11 (8) ◽  
pp. 2400 ◽  
Author(s):  
Karthikeyan Mariappan ◽  
Deyi Zhou

Agriculture is the main sources of income for humans. Likewise, agriculture is the backbone of the Indian economy. In India, Tamil Nadu regional state has a wide range of possibilities to produce all varieties of organic products due to its diverse agro-climatic condition. This research aimed to identify the economics and efficiency of organic farming, and the possibilities to reduce farmers’ suicides in the Tamil Nadu region through the organic agriculture concept. The emphasis was on farmers, producers, researchers, and marketers entering the sustainable economy through organic farming by reducing input cost and high profit in cultivation. A survey was conducted to gather data. One way analysis of variance (ANOVA) has been used to test the hypothesis regards the cost and profit of rice production. The results showed that there was a significant difference in profitability between organic and conventional farming methods. It is very transparent that organic farming is the leading concept of sustainable agricultural development with better organic manures that can improve soil fertility, better yield, less input cost and better return than conventional farming. The study suggests that by reducing the cost of cultivation and get a marginal return through organic farming method to poor and small scale farmers will reduce socio-economic problems such as farmers’ suicides in the future of Indian agriculture.


Author(s):  
Deep K. Datta-Ray

The history of Indian diplomacy conceptualises diplomacy racially—as invented by the West—and restrictively—to offence. This is ‘analytic-violence’ and it explains the berating of Indians for mimicking diplomacy incorrectly or unthinkingly, and the deleting, dismissing, or denigrating, of diplomatic practices contradicting history’s conception. To relieve history from these offences, a new method is presented, ‘Producer-Centred Research’ (PCR). Initiating with abduction, an insight into a problem—in this case Indian diplomacy’s compromised historicisation—PCR solves it by converting history’s racist rationality into ‘rationalities’. The plurality renders rationality one of many, permitting PCR’s searching for rationalities not as a function of rationality but robust practices explicable in producer’s terms. Doing so is exegesis. It reveals India’s nuclear diplomacy as unique, for being organised by defence, not offence. Moreover, offence’s premise of security as exceeding opponent’s hostility renders it chimerical for such a security is, paradoxically, reliant on expanding arsenals. Additionally, doing so is a response to opponents. This fragments sovereignty and abdicates control for one is dependent on opponent’s choices. Defence, however, does not instigate opponents and so really delivers security by minimising arsenals since offence is eschewed. Doing so is not a response to opponents and so maintains sovereignty and retains control by denying others the right to offense. The cost of defence is courage, for instance, choosing to live in the shadow of nuclear annihilation. Exegesis discloses Balakot as a shift from defence to offence, so to relieve the Bharatiya Janata Party’s (BJP) leadership of having to be courageous. The intensity of the intention to discard courage is apparent in the price the BJP paid. This included equating India with Pakistan, permitting it to escalate the conflict, and so imperiling all humanity in a manner beyond history.


2007 ◽  
Vol 46 (7) ◽  
pp. 1067-1079 ◽  
Author(s):  
M. Kanda ◽  
M. Kanega ◽  
T. Kawai ◽  
R. Moriwaki ◽  
H. Sugawara

Abstract Urban climate experimental results from the Comprehensive Outdoor Scale Model (COSMO) were used to estimate roughness lengths for momentum and heat. Two different physical scale models were used to investigate the scale dependence of the roughness lengths; the large scale model included an aligned array of 1.5-m concrete cubes, and the small scale model had a geometrically similar array of 0.15-m concrete cubes. Only turbulent data from the unstable boundary layers were considered. The roughness length for momentum relative to the obstacle height was dependent on wind direction, but the scale dependence was not evident. Estimated values agreed well with a conventional morphometric relationship. The logarithm of the roughness length for heat relative to the obstacle height depended on the scale but was insensitive to wind direction. COSMO data were used successfully to regress a theoretical relationship between κB−1, the logarithmic ratio of roughness length for momentum to heat, and Re*, the roughness Reynolds number. Values of κB−1 associated with Re* for three different urban sites from previous field experiments were intercompared. A surprising finding was that, even though surface geometry differed from site to site, the regressed function agreed with data from the three urban sites as well as with the COSMO data. Field data showed that κB−1 values decreased as the areal fraction of vegetation increased. The observed dependency of the bulk transfer coefficient on atmospheric stability in the COSMO data could be reproduced using the regressed function of Re* and κB−1, together with a Monin–Obukhov similarity framework.


2014 ◽  
Vol 136 (4) ◽  
Author(s):  
Adel M. Abdel Dayem

An innovative solar desalination system is successfully designed, manufactured, and experimentally tested at Makkah, 21.4 degN. The system consists of 1.15 m2 flat-plate collector as a heat source and a desalination unit. The unit is about 400 l vertical cylindrical insulated tank. It includes storage, evaporator, and condenser of hot salt-water that is fed from the collector. The heated water in the collector is raised naturally to the unit bottom at which it is used as storage. A high pressure pump is used to inject the water vertically up through 1-mm three nozzles inside the unit. The hot salt-water is atomized inside the unit where the produced vapor is condensed on the inner surfaces of the unit outer walls to outside. The system was experimentally tested under different weather conditions. It is obtained that the system can produce about 9 l a day per quadratic meter of collector surface area. By that it can produce about 1.6 l/kWh of solar energy. Moreover, the water temperature has a great effect on the system performance although the scaling possibility is becoming significant. By that way the cost of a liter water production is relatively high and is obtained as 0.5 US$.


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