High-resolution x-ray scattering studies of charge ordering in highly correlated electron systems

Many important properties of transition metal oxides such as, copper oxide high- temperature superconductivity and colossal magnetoresistance (CMR) in manganites are due to strong electron-electron interactions, and hence these systems are called highly correlated systems. These materials are characterised by the coexistence of different kinds of order, including charge, orbital, and magnetic moment. This thesis contains high-resolution X-ray scattering studies of charge ordering in such systems namely the high-T(_c) copper oxides isostructural system, La(_2-x)Sr(_x)NiO(_4)) with various Sr concentrations (x = 0.33 - 0.2), and the CMR manganite system, Nd(_1/2)Sr(_1/2)MnO(_3)). It also includes a review of charge ordering in a large variety of transition metal oxides, such as ferrates, vanadates, cobaltates, nickelates, manganites, and cuprates systems, which have been reported to date in the scientific literature. Using high-resolution synchrotron X-ray scattering, it has been demonstrated that the charge stripes exist in a series of single crystals of La(_2-x)Sr(_x)NiO(_4)) with Sr concentrations (x = 0.33 - 0.2) at low temperatures. Satellite reflections due to the charge ordering were found with the wavevector (2Ɛ, 0, 1) below the charge ordering transition temperature, Tco, where 2 Ɛ is the amount of separation from the corresponding Bragg peak. The charge stripes are shown to be two-dimensional in nature both by measurements of their correlation lengths and by measurement of the critical exponents of the charge stripe melting transition with an anomaly at x = 0.25. The results show by decreasing the hole concentration from the x = 0.33 to 0.2, the well-correlated charge stripes change to a glassy state at x = 0.25. The electronic transition into the charge stripe phase is second-order without any corresponding structural transition. Above the second-order transition critical scattering was observed due to fluctuations into the charge stripe phase. In a single-crystal of Nd(_1/2)Sr(_1/2)MnO(_3) a series of phase transitions were observed using high-resolution synchrotron X-ray scattering. Above the charge ordering transition temperature, Tco, by measuring the peak profiles of Bragg reflections as a function of temperature, it was found that this crystal undergoes two transitions corresponding to the transition from a paramagnetic- to a ferromagnetic state at T ≈ 252 K, and the formation of a mixture of the antiferromagnetic and ferromagnetic phases below T ≈ 200 K. Below the charge ordering temperature, Tco =162 K, additional satellite reflections with the wavevector, q = (1/2, 0, 0), were observed due to Jahn-Teller distortion of the MnO(_6) octahedra caused by charge- and orbital ordering in sample. This transition was observed to be of first-order with a hysteresis width of 10 K. In addition, another very weak satellites with wavevector (1/2, 1, 1/2) were observed possibly due to spin ordering

Industry 4.0: Industrial IoT Enhancement and WSN Performance Analysis

L'abstract è presente nell'allegato / the abstract is in the attachmen

Social Capital and Psychological Capital as Predictors of Performance and Wellbeing in the Indian Context

The incremental contribution of social capital over psychological capital in explaining employees’ performance and wellbeing in the Indian Banking sector is explored. Data was collected from 101 clerical employees, using standardised questionnaires and they have adequate reliability coefficients. Data was analysed by hierarchical regression method. None of the demographics variables predicted any of the outcome variables. Self efficacy was the only psychological capital which emerged as the significant predictor of both performance and wellbeing. Bonding capital emerged as a significant predictor of job performance. Bridging capital caused a negative variance in both job performance and well being. Results were discussed in the light of existing theories and framework

Developing Entrepreneurial Mindset in Industrial Engineering Classes: A Case Study

Instilling entrepreneurial mindset among engineering students is one of the challenges in engineering education. This paper presents the efforts to improve a core undergraduate industrial engineering course, Designing Value in Supply Chain, to infuse entrepreneurial thinking among students using an internally funded grant by Kern Entrepreneurial Engineering Network (KEEN). For this purpose, three new course modules are designed and their effectiveness on student learning is evaluated. This course is ideal for establishing entrepreneurially minded learning (EML) as a systematic approach is required for managing the chain of supply, especially since the impacts of the decisions are not isolated and will be spread out through the entire chain. In addition, creative multidisciplinary knowledge is required to address most of the supply chain challenges. The proposed modules are expected to promote students’ creative thinking, curiosity, collaboration and communication skills, and enable them to identify the opportunities where they can apply their technical skills to create value in the community based on customers’ expectations. These factors are key pillars of EML as proposed by KEEN. In the first course module, students propose a new product to be released to the market (idea generation). They complete this module as the product moves toward the end user in the supply chain following the concepts they learn during the term. This module enables the students to observe the domino impact of the decisions they make in the initial stages of supply chain and enhances structured learning experience by linking different concepts. In the second module, in order to expose the students to real life applications of the course content, wireless consumption data provided by students is used to practice different demand forecasting methods. Students also need to provide some economic analysis to choose the best solution alternative regarding their forecasted values. This module makes the learning process more meaningful as the learners observe a real life application of the subject. In the third module, students practice energy management in order to minimize energy waste as one of the most important types of waste in lean production systems. In this module, they are expected to determine several sources of energy waste on campus and propose action plans, and estimate the economic impact of their solution. As a result of this project, students learn how to create value and communicate an engineering solution in terms of economic benefits. Students provide a report for each module which is graded based on designed rubrics. All these modules are performed in teams which in turn improves students’ team work and collaboration skills. This paper elaborates the details of each module and learning outcomes, and presents the student evaluation results, and at the end discusses the lessons learned

Penglibatan Masyarakat Awam Di Negeri Kelantan Dalam Isu-Isu Berkaitan Persekitaran

Pada dekad-dekad kebelakangan ini, isu-isu persekitaran menjadi semakin kritikal dan kompleks untuk diselesaikan secara eksklusif melalui pendekatan sains, teknikal dan perundangan semata-mata. Justeru, penglibatan masyarakat awam secara aktif diperlukan dalam penyelesaian kepada masalah berkenaan. Kajian ini bertujuan mengkaji perbezaan min secara signifikan bagi faktor demografi dengan pengetahuan responden mengenai isu-isu persekitaran di kawasan kajian

Efisiensi Pengurusan Air Tidak Berhasil (Nrw) Di Negeri Kelantan; Kajian Kes Bechah Tendong

Negeri Kelantan mencatatkan kadar NRW tinggi setiap tahun ke belakangan ini. Antara kawasan yang mencatat paras NRW tertinggi ialah Bechah Tendong dengan nilai 62%. Kajian ini bertujuan mengenalpasti permasalahan NRW, implikasi kewangan, menilai tahap kesedaran awam dan membangunkan SOP komprehensif. Analisis data kualitatif telah dilakukan menggunakan Perisian QSR Nvivo. Nisbah faedah-kos (BCR), Tempoh bayar balik (PBP), Pulangan atas pelaburan (ROI), Nilai kini bersih (NPV) digunakan bagi penilaian ekonomi. Hasil analisis Nvivo mendapati isu yang paling dominan dan memberi kesan besar dalam pelaksanaan NRW adalah berkaitan dengan pelaksanaan kerja, kekangan dalam melaksanakan kerja dan kontrak serta kurang kefahaman konsep pengurusan NRW yang menjadi isu besar kepada kegagalan pelaksanaan NRW dengan berkesan. Nilai indikator ekonomi yang diperoleh adalah BCR= 1.03, PBP = 9.32, ROI (%) = 6.40 dan NPV= RM 405,576.82. Berdasarkan analisis kolerasi, hubungan paling signifikan diperolehi di antara masalah sikap dan undang-undang dengan nilai pekali korelasi pearson, r=0.364. Hasil kajian menunjukkan paras NRW semasa berjaya dikurangkan sebanyak 17.35% iaitu daripada 62% menjadi 44.65% bagi tempoh 5 tahun (2014-2018). Kesimpulan, kajian ini mempunyai potensi untuk menjana pendapatan melalui penjimatan kepada pihak berkaitan. Seterusnya, merealisasikan hasrat keefisienan pengurusan NRW dicapai

DEVELOPING AN OPTIMAL MODEL FOR URBAN WASTE MANAGEMENT SYSTEMS WITH SUSTAINABLE DEVELOPMENT APPROACH: A CASE STUDY OF TEHRAN

Abstract. Today, choosing an appropriate waste disposal option for cities, especially crowded cities such as Tehran, has become one of the important environmental issues. In fact, one of the areas where the reform can play an important role in promoting the municipal waste management system is the choice of the final disposal method of waste, since it is a multi-criteria and complex problem and has different environmental, social, technological and economic dimensions. In recent years, due to the increase in the production of municipal wastes in the metropolis of Tehran and the environmental consequences of their disproportionate disposal, and on the other hand, due to the disadvantages and advantages of any waste disposal method, including recycling, compost, waste incinerators and sanitary landfill, a variety of models and methods have been used to evaluate waste disposal systems in the city of Tehran and to select the best waste management options. But the problem of final disposal of waste from Tehran is still one of the main concerns of the environmental management of this metropolis. Because of the difference in the nature of waste materials in Tehran and its constituent parts, a waste disposal system for waste management in Tehran, is not a satisfactory solution, and in order to achieve high efficiency as well as covering all materials, several waste management and disposal units should be used incombination. On the other hand, each of these municipal waste disposal systems will also have costs and revenues. Therefore, considering this point, the percentage of input of waste to disposal systems is important. So in order to achieve this, in this research we have to provide an optimal model using PSO in order to achieve the optimal combination of municipal waste management systems and determining the optimal amount of waste for each of these waste disposal systems, in accordance with the waste analyzes in Tehran, in order to achieve the highest efficiency, reduce economic and environmental costs, and increase the income.Keywords: Urban Waste Management System, Optimal Pattern, PSO, Sustainable development, cost, revenue