2,201 research outputs found
Energy dissipation prediction of particle dampers
This paper presents initial work on developing models for predicting particle dampers (PDs) behaviour using the Discrete Element Method (DEM). In the DEM approach, individual particles are typically represented as elements with mass and rotational inertia. Contacts between particles and with walls are represented using springs, dampers and sliding friction interfaces. In order to use DEM to predict damper behaviour adequately, it is important to identify representative models of the contact conditions. It is particularly important to get the appropriate trade-off between accuracy and computational efficiency as PDs have so many individual elements. In order to understand appropriate models, experimental work was carried out to understand interactions between the typically small (1.5–3 mm diameter) particles used. Measurements were made of coefficient of restitution and interface friction. These were used to give an indication of the level of uncertainty that the simplest (linear) models might assume. These data were used to predict energy dissipation in a PD via a DEM simulation. The results were compared with that of an experiment
The Fossil Endgame: Strategic Oil Price Discrimination and Carbon Taxation
This paper analyzes how fossil fuel-producing countries can counteract climate policy. We analyze the exhaustion of oil resources and the subsequent transition to a backstop technology as a strategic game between the consumers and producers of oil, which we refer to simply as “OECD” and “OPEC,” respectively. The consumers, OECD, derive benefits from oil, but worry about climate effects from carbon dioxide emissions. OECD has two instruments to manage this: it can tax fuel consumption and decide when to switch to a carbon-neutral backstop technology. The tax reduces climate damage and also appropriates some of the resource rent. OPEC retaliates by choosing a strategy of price discrimination, subsidizing oil in its domestic markets. The results show that price discrimination enables OPEC to avoid some of the adverse consequences of OECD’s fuel tax and its switch to the backstop technology by consuming a larger share of the oil in its own domestic markets. Our results suggest that persuading fossil exporters to stop subsidizing domestic consumption will be difficult.dynamic games, stock externalities, carbon tax, non-renewable resources, energy subsidies
Increasing the Size of a Piece of Popcorn
Popcorn is an extremely popular snack food in the world today. Thermodynamics
can be used to analyze how popcorn is produced. By treating the popping
mechanism of the corn as a thermodynamic expansion, a method of increasing the
volume or size of a kernel of popcorn can be studied. By lowering the pressure
surrounding the unpopped kernel, one can use a thermodynamic argument to show
that the expanded volume of the kernel when it pops must increase. In this
project, a variety of experiments are run to test the validity of this theory.
The results show that there is a significant increase in the average kernel
size when the pressure of the surroundings is reduced.Comment: Latex document, 14 pages, 4 figures, 1 page of table
Presence of Mycoplasma sp. in Lambs with Lung Lesions
Objectives: To test the impact of NPCoat administration on the prevalence of lung lesions in lambs
Meeting global temperature targets-the role of bioenergy with carbon capture and storage
In order to meet stringent temperature targets, active removal of CO2 from the atmosphere may be required in the long run. Such negative emissions can be materialized when well-performing bioenergy systems are combined with carbon capture and storage (BECCS). Here, we develop an integrated global energy system and climate model to evaluate the role of BECCS in reaching ambitious temperature targets. We present emission, concentration and temperature pathways towards 1.5 and 2 degrees C targets. Our model results demonstrate that BECCS makes it feasible to reach temperature targets that are otherwise out of reach, provided that a temporary overshoot of the target is accepted. Additionally, stringent temperature targets can be met at considerably lower cost if BECCS is available. However, the economic benefit of BECCS nearly vanishes if an overshoot of the temperature target is not allowed. Finally, the least-cost emission pathway over the next 50 years towards a 1.5 degrees C overshoot target with BECCS is almost identical to a pathway leading to a 2 degrees C ceiling target
Optimisation of a distribution system in the retail industry: An Australian retail industry
This paper develops a mathematical model based on inventory routing problem that aims to minimise transportation cost, inventory carrying cost and optimises delivery schedules in a retail Australian industry. A supply chain is considered which comprises of a single distribution centre, having homogenous fleet of vehicles, supplying a single product to multiple retailers having deterministic demand. The mathematical model takes into account varying level of road congestion.N/
Design of few-mode fibers with M-modes and low differential mode delay
In this paper, we investigate the design of few-mode fibers (FMFs) guiding 2 to 12 linearly polarized (LP) modes with low differential mode delay (DMD) over the C-band, suitable for long-haul transmission. Two different types of refractive index profile have been considered: a graded-core with a cladding trench (GCCT) profile and a multi-step-index (MSI) profile. The profiles parameters are optimized in order to achieve: the lowest possible DMD and macro-bend losses (MBL) lower than the ITU-T standard recommendation. The optimization results show that the MSI profiles present lower DMD than the minimum achieved with a GCCT profile. Moreover, it is shown that the optimum DMD and the MBL scale with the number of modes for both profiles. The optimum DMD obtained for 12 LP modes is lower than 3 ps/km using a GCCT profile and lower than 2.5 ps/km using a MSI profile. The optimization results reveal that the most preponderant parameter of the GCCT profile is the refractive index relative difference at the core center, Δnco. Reducing Δn co, the DMD is reduced at the expense of increasing the MBL. Regarding the MSI profiles, it is shown that 64 steps are required to obtain a DMD improvement considering 12 LP modes. Finally, the impact of the fabrication margins on the optimum DMD is analyzed. The probability of having a manufactured FMF with 12 LP modes and DMD lower than 12 ps/km is approximately 68% using a GCCT profile and 16% using a MSI profile
Shearing Lambs Improves Growth Performance During Periods with Elevated Thermal Load
The purpose of this study was to determine if average daily gain (ADG) is improved in shorn lambs versus non-shorn lambs in the summer months in the upper Midwestern United States. Forty-nine purebred Hampshire and Columbia ram (n = 10 Hampshire and 4 Columbia) and ewe (n = 22 Hampshire and 13 Columbia) lambs were grouped by breed, sex, age (104 ± 1.7 days of age), and initial weight (109 ± 3.5 lbs) into shorn (n=26) and non-shorn (n=23) groups. After shearing (3 June 2004), shorn sheep had approximately 0.1 inches of wool-cover. Lambs were weighed 1, 29, and 57 days following shearing. During the first 28 day period following shearing (period 1), there was no difference in average daily gain between shorn and non-shorn lambs (0.8 ± 0.04 vs 0.82 ± 0.04 lbs/day, respectively). In the second 28 day period (period 2), shorn lambs had a greater average daily gain than non-shorn lambs (1.02 ± 0.06 vs 0.92 ± 0.06 lbs/day, respectively). Period 2 had greater mean (68.9 vs. 63.4 oF, respectively), minimum (59.7 vs 54.1oF, respectively), and maximum (78.2 vs. 73.8oF, respectively) daily ambient air temperature and greater mean humidity (73.97 vs. 68.2 %, respectively) than period 1. The calculated temperature humidity index (THI) was also greater in period 2 than period 1 (66.9 vs. 62.24, respectively). These data indicate that shorn lambs grow more rapidly than non-shorn lambs during periods of elevated temperature, humidity, and THI
PENINGKATAN EFISIENSI KINERJA MELALUI PEMBUATAN APLIKASI BERBASIS DESKTOP SEBAGAI UPAYA MEMBANTU PENJUALAN DAN PEMBELIAN PRODUK UMKM
Abstrak: Tidak terkomputerisasinya dokumen pada usaha kecil menengah akan mempersulit perusaaan dalam melakukan pendataan transaksi, baik itu dalam pengontrolan alur kas, menghitung keuntungan, serta mengurangi kehilangan barang. Pengabdian ini ditujukan untuk membatu salah satu usaha kecil menengah di Pontianak agar mempermudah dalam mendata transaksi penjulan dan pembeliannya untuk menghitung keuntungan. Metode yang digunakan antara lain dengan melakukan wawancara langsung dengan pemilik usaha dan melakukan obervasi terhadap proses bisnis yang ada, melakukan analisis perangkat lunak, pembuatan perangkat lunak, dan mengimplemantasikan kepada pihak manajemen CV. Suskes Mandiri Pontianak. Dari aplikasi yan sudah diterapkan, CV. Sukses Mandiri dapat menggunakan aplikasi berbasis desktop yang dapat membantu efisiensi kinerja serta penaikan jumlah penjualan sebesar 30.05 % dan pembelian produk sebesar 2.63 % pada bulan pertama penggunaan aplikasi.  Abstract: Un-Computerize document in the small-middle entrepreneur will make more complicate for controlling transaction data collection, control their cash flow, count the benefit, and reduce item lost. These social services help one of small-middle entrepreneur at Pontianak to control transaction data collection in selling and buying to count benefit. Methods that have been used are customer interview with business owner, observation, software analysis, software development, and implement software to CV. Sukses Mandiri’s management. From the software that was implement in CV. Sukses Mandiri can be used in desktop based application which help them to increase performance efficiency and increase selling by 23.6 % and product purchasing by 21.3% in the first month application used
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