Sample 1

 Ghazaw,  Y. M.(2011). Design and analysis of a canal section for minimum water loss. Alexandria Engineering Journal , 50(4), 337-344.

Abstract

Background. Seepage and evaporation are the most serious forms of water loss in an irrigation canal network. Seepage loss depends on the channel geometry, while evaporation loss is proportional to the area of free surface.

Methods. In this paper, a methodology to determine the optimal canal dimensions for a particular discharge is developed. The nonlinear water loss function, for the canal, which comprises seepage and evaporation loss, was derived. Two constraints (minimum permissible velocity as a limit for sedimentation and maximum permissible velocity as a limit for erosion of canal) have been taken into consideration in the canal design procedure. Using Lagrange’s method of undetermined multipliers, the optimal canal dimensions were obtained for minimum water loss. A computer program was developed to carry out design calculation for the optimal canal dimensions.

Results. The results are plotted in form of a set of design charts.

Conclusions.The proposed charts facilitate easy design of the optimal canal dimensions guaranteeing minimum water loss. Water loss from the canal section can be estimated from these charts without going through the conventional and cumbersome trial and error method. Sensitivity analysis had been included to demonstrate the impact of important parameters.

Keywords

Design charts; Canal design; Optimal dimensions; Seepage loss; Evaporation loss

Sample 2

Moharram, K.A., Abd-Elhady, M.S. & Kandil, H.A.(2013). Enhancing the performance of photovoltaic panels by water cooling. Ain Shams Engineering Journal , 4 (4), 869-877.

Abstract

Background. The objective of the research is to minimize the amount of water and electrical energy needed for cooling of the solar panels, especially in hot arid regions, e.g., desert areas in Egypt.

Methods. A cooling system has been developed based on water spraying of PV panels. A mathematical model has been used to determine when to start cooling of the PV panels as the temperature of the panels reaches the maximum allowable temperature (MAT).

Results. A cooling model has been developed to determine how long it takes to cool down the PV panels to its normal operating temperature, i.e., 35 °C, based on the proposed cooling system. Both models, the heating rate model and the cooling rate model, are validated experimentally.

Conclusions. Based on the heating and cooling rate models, it is found that the PV panels yield the highest output energy if cooling of the panels starts when the temperature of the PV panels reaches a maximum allowable temperature (MAT) of 45 °C. The MAT is a compromise temperature between the output energy from the PV panels and the energy needed for cooling.

Keywords

Photovoltaic; Cooling; Overheating

Sample 3

Fischer, T., Gneiting C. & Hornberger K. (2013, June 6). Wigner function for the orientation state. New Journal of Physics . Retrieved November 2, 2017 from https://www.researchgate.net/publication/232244736_Wigner_function_for_the_orientation_stat

GENERAL SCIENTIFIC SUMMARY

Introduction and background. The Wigner quasi-probability distribution, together with the general Wigner–Weyl transformation, allow one to formulate quantum mechanics in terms of real functions on the associated classical phase space. This representation is widely applied in statistical mechanics, quantum optics, quantum chemistry, and in many other areas of quantum physics where an intuition for the corresponding classical dynamics is helpful. While the Wigner function was originally defined for point particles, many generalizations to other degrees of freedom have been proposed. However, an appropriate Wigner representation for the rotation dynamics of extended objects has been missing so far.

Main results. A Wigner function for the orientation degree of freedom of rigid bodies is introduced, which uses the Euler angles and the associated canonical momenta as the appropriate phase space coordinates. It inherits all the relevant properties known from the original Wigner function, including the quasi-probability interpretation. As a main difference, the momentum coordinates assume only discrete values since they are components of the angular momentum. This discreteness, which is a necessary consequence of quantization, vanishes in the semiclassical limit.

Wider implications. The phase space representation should be a versatile tool whenever one is interested in rotating quantum objects such as molecules. In particular, it will be useful for visualizing their state of motion, for semiclassical approximations, and for studying the quantum-classical transition.

Sample 3

Gibbs, Zachary M, LaLonde, Aaron & G Jeffrey Snyder (2013, July 23). Optical band gap and the Burstein–Moss effect in iodine doped PbTe using diffuse reflectance infrared Fourier transform spectroscopy. New Journal of Physics (New J. Phys.).  Retrieved November 2, 2017 from http://www.njp.org/ doi:10.1088/1367-2630/15/7/075020

General Scientific Summary

Introduction and background. Optical absorption is the most direct way to measure band gaps in semiconductors. High efficiency thermoelectric materials such as lead telluride are typically heavily doped semiconductors, where the high efficiency is understood to be related to its complex band structure. Optical absorption may then be a direct way of measuring the electronic band structure enabling properties modification or engineering.

Main results. In this paper, we measure the optical absorption spectra in iodine doped PbTe at various doping levels. Diffuse reflectance infrared spectroscopy (DRIFTS) is shown to be a very precise (within ~0.01 eV) method of determining the optical gap in PbTe (~0.3 eV for undoped material). The optical gap is found to change considerably in doped samples primarily because of the Burstein–Moss shift—an increase in optical absorption energy as a result of an increasing Fermi level (electronic chemical potential). Band gap renormalization, the narrowing of the band gap as carriers are added to a semiconductor, is also estimated to be ~0.1 eV at high doping levels.

Wider implications. DRIFTS has been shown to be highly sensitive to small changes in band gap and in the chemical potential (Fermi level) for small band gap semiconductors. The Burstein–Moss shift in doped semiconducting materials is quite significant and influences the accuracy of determining the band gap using optical methods. Further, renormalization—or gap narrowing with carrier concentration—proves to be important in PbTe which may ultimately affect how we understand the rigid band approximation and transport properties. DRIFTS, a simple technique using powder samples, can be a powerful tool for estimating the band gap in thermoelectric materials as a function of doping, alloying, or even temperature.

Text 4. Types of Abstracts

An abstract is not only a brief summary of a document but it also must be an "accurate representation of the contents of a document." To create an abstract, an abstractor or a writer needs to identify two kinds of information about the document, metadata (data about the data) and the essence of its informative contents. Metadata is a description of what kind of information it is, which includes the purpose, scope, and research methodology. Informative contents are material contents of the document, which includes conclusions, suggestions, and recommendations. Depending on which information it contains, an abstract can be classified into two types: descriptive (or indicative) abstract and informative abstract. Although you'll see two types of abstracts—informative and descriptive—most writers now provide informative abstracts of their work.

Descriptive abstract

A descriptive abstract, even though the word ‘description’ gives the idea of a long and elaborate article, is the shorter of the two types of abstracts. This type of abstract will give only a very vague idea of the content of the research paper. It outlines the topics covered in a piece of writing so the reader can decide whether to read the entire document. In many ways, the descriptive abstract is like a table of contents in paragraph form. Unlike reading an informative abstract, reading a descriptive abstract cannot substitute for reading the document because it does not capture the content of the piece. Nor does a descriptive abstract fulfill the other main goals of abstracts as well as informative abstracts do. For all these reasons, descriptive abstracts are less and less common. Descriptive abstracts are generally used for humanities and social science papers or psychology essays. In this type of abstracts emphasis is placed on the problem and method. Such abstracts may be required for conference paper proposals or for progress reports. Descriptive abstracts contain only metadata of the document (background, purpose, particular interest/focus of paper, overview of contents) and does not include informative contents. Whereas, informative abstract includes both metadata and informative contents. In informative abstracts, which are written after the project has been completed, care is given to providing information on the results and conclusion of the project. While descriptive abstract is short in length and common in abstraction services, author produced abstracts such as those of thesis, journal essays, and articles are usually informative ones.

While writing a descriptive abstract, pick the most generalized aspects in your research paper. Topic is one point to be included. You do not have to elaborate much on the topic, or any other point for that matter, if the abstract is a descriptive one. Just mention what is the subject area and what the topic is. There is no need to explain about the specific angle you are studying or the conclusion. Just generally talk about the method you are using and the reason why you chose to research on the topic. You can include some general background information on the topic if you wish to and if there is space.

Another feature of a descriptive abstract is its length. It is expected to be just around 100 words. That explains why it is incapable of containing any details of the assignment. Do not reveal much about the study or the report. One purpose of such an abstract is to leave the reader with no choice but to read the complete document to get the details of the research. Keep this aspect in mind while writing the abstract. Your reader should not understand anything more than the subject your research is related to and the topic you are dealing with.

You can also mention the sources you have used for your research. Again, just mention the author and the book, without getting into anymore bibliographical details. There is very less space for anything to be discussed at all. The short document becomes favorable when you prefer not to reveal much in the research paper abstract. But if you want your reader to be aware of the contents before reading through the entire research paper, the length limitations of a descriptive abstract becomes tough to deal with.