Solution-Processable Graphene Oxide as an Efficient Hole Injection Layer for High Luminance Organic Light-Emitting Diodes

The application of solution-processable graphene oxide (GO) as hole injection layer in organic light-emitting diodes (OLEDs) is demonstrated. High luminance of over 53,000 cd m-2 is obtained at only 10 V. The results will unlock a route of applying GO in flexible OLEDs and other electrode applications.Comment: 14 pages, 3 figures, 1 tabl

Recovery of vanadium pentoxide from spent catalyst used in the manufacture of sulphuric acid

Vanadium has many industrial uses and its contribution to environmental contamination is increasing all the time. Recovery of vanadium pentoxide from spent sulphuric acid catalysts was performed using a three-step process involving acid leaching, oxidation and precipitation. Several different acids were used in the leaching process. Finally, sulphuric acid was used in various concentrations, solid to liquid ratios, stirring times and temperatures. A high solid/liquid ratio in the leaching stage was used to obtain high concentration of vanadium pentoxide and low acid consumption that allowed direct precipitation without the use of extraction by rather expensive organic solvents. Sodium carbonate solution of one mole/liter concentration was used in the precipitation stage. An industrial application including material balance and operating conditions with an overall vanadium pentoxide recovery efficiency of (70%) was proposed

Pengaruh Kombinasi Media Pembelajaran terhadap Minat Belajar Mahasiswa pada Mata Kuliah Teknologi Pembelajaran Akuntansi

Tujuan penelitian ini adalah untuk mengetahui pengaruh kombinasi media pembelajaran (Microsoft PowerPoint dan Ulead Video Studio) terhadap minat belajar mahasiswa pada perkuliahan Teknologi Pembelajaran Akuntansi. Populasi yang digunakan dalam penelitian ini adalah mahasiswa semester IV Pendidikan Ekonomi BKK Pendidikan Akuntansi yang sedang mengikuti mata kuliah Teknologi Pembelajaran Akuntansi. Dalam penelitian ini, teknik pengambilan sampel yang dipilih adalah Nonprobability Sampling dengan Teknik Sampling Jenuh. Data yang digunakan adalah data primer yang berasal dari angket yang disebarkan oleh peneliti kepada mahasiswa sebagai responden pada akhir perkuliahan. Penelitian ini merupakan penelitian kuantitatif dengan menggunakan metode eksperimen, metode uji statistik yang digunakan adalah Uji-T dengan melakukan uji persyaratan analisis terlebih dahulu.Hasil penelitian menunjukkan bahwa terdapat pengaruh penggunaan kombinasi media pembelajaran terhadap minat belajar mahasiswa. Hal tersebut ditunjukkan melalui perhitungan Uji-T yang menghasilkan nilai t hitung sebesar 2,040 yang melebihi nilai t tabel sebesar 1,998 dan P-Value sebesar 0,045 lebih kecil dari taraf signifikansi yang telah ditentukan yaitu sebesar 0,05.Kata Kunci: Kombinasi Media Pembelajaran, Minat Belajar ABSTRACTThe purpose of this research is to know the effect of learning media combination (Microsoft PowerPoint and Ulead Video Studio) toward students interest in learning on Teknologi Pembelajaran Akuntansi course. The population that is used in this research is the 4th semester students of Economic Accounting Education who are joining Teknologi Pembelajaran Akuntansi course. In this research, sampling technique which choosen was Nonprobability Sampling withJenuh Sampling Technique. The determination of the group will be treated experimental and control is conducted randomly. The data that used is primary data which come from distributed questionnaries by researcher to students as respondents when the course ends. This research is quantitative research using experimental methods, statistical methods which used is T-Test with the test requirements prior analysis.The research result shows that learning media combination has effect to students interest in learning. It is shown by t0 = 2,040 which exceed the value of its critical value for 1,998 and P-Value for 0,045 smaller than a predetermined significance level for 0,05. Keyword: Learning Media Combination, Students Interest in LearningABSTRAKTujuan penelitian ini adalah untuk mengetahui pengaruh kombinasi media pembelajaran (Microsoft PowerPoint dan Ulead Video Studio) terhadap minat belajar mahasiswa pada perkuliahan Teknologi Pembelajaran Akuntansi. Populasi yang digunakan dalam penelitian ini adalah mahasiswa semester IV Pendidikan Ekonomi BKK Pendidikan Akuntansi yang sedang mengikuti mata kuliah Teknologi Pembelajaran Akuntansi. Dalam penelitian ini, teknik pengambilan sampel yang dipilih adalah Nonprobability Sampling dengan Teknik Sampling Jenuh. Data yang digunakan adalah data primer yang berasal dari angket yang disebarkan oleh peneliti kepada mahasiswa sebagai responden pada akhir perkuliahan. Penelitian ini merupakan penelitian kuantitatif dengan menggunakan metode eksperimen, metode uji statistik yang digunakan adalah Uji-T dengan melakukan uji persyaratan analisis terlebih dahulu.Hasil penelitian menunjukkan bahwa terdapat pengaruh penggunaan kombinasi media pembelajaran terhadap minat belajar mahasiswa. Hal tersebut ditunjukkan melalui perhitungan Uji-T yang menghasilkan nilai t hitung sebesar 2,040 yang melebihi nilai t tabel sebesar 1,998 dan P-Value sebesar 0,045 lebih kecil dari taraf signifikansi yang telah ditentukan yaitu sebesar 0,05.Kata Kunci: Kombinasi Media Pembelajaran, Minat Belajar ABSTRACTThe purpose of this research is to know the effect of learning media combination (Microsoft PowerPoint and Ulead Video Studio) toward students interest in learning on Teknologi Pembelajaran Akuntansi course. The population that is used in this research is the 4th semester students of Economic Accounting Education who are joining Teknologi Pembelajaran Akuntansi course. In this research, sampling technique which choosen was Nonprobability Sampling withJenuh Sampling Technique. The determination of the group will be treated experimental and control is conducted randomly. The data that used is primary data which come from distributed questionnaries by researcher to students as respondents when the course ends. This research is quantitative research using experimental methods, statistical methods which used is T-Test with the test requirements prior analysis.The research result shows that learning media combination has effect to students interest in learning. It is shown by t0 = 2,040 which exceed the value of its critical value for 1,998 and P-Value for 0,045 smaller than a predetermined significance level for 0,05

The Effectiveness of a Proposed Enrichment Program Based on Problem-Solving and Problem Posing in Developing the Ability of Mathematical Reasoning and Sense-Making among Grade Ten High Achievers

This study aimed to reveal the effectiveness of a proposed enrichment program based on problem-solving and problem posing in developing the ability of the mathematical reasoning and sense making among students of high achievement. To achieve this goal, an enrichment training program was designed to focus on a set of mathematical ideas and skills in mathematics using problem-solving and problem- posing strategies to solve and pose non-routine mathematical problems for students of high achievement to develop their mathematical reasoning and sense making ability. The researcher designed a test to measure the mathematical reasoning and sense making. In addition, the Test of Mathematical Abilities (TOMA-3) was used to measure the students' mathematical abilities before the experiment. The sample of the study consisted of 63 grade ten high achievers randomly selected from South Batinah governorate, which was divided into control and experimental groups. For testing the study hypothesis, data was analyzed by analysis of covariance (ANCOVA) in which eta squared was obtained. The results showed that the proposed program was effective and the mathematical reasoning and sense making skills were highly achieved

Defining the cost of the Egyptian lymphatic filariasis elimination programme

BACKGROUND: Lymphatic filariasis (LF) is targeted for global elimination. LF elimination programmes in different countries, including Egypt, are supported financially by national and international agencies. The national programme in Egypt is based on mass drug administration (MDA) of an annual dose of a combination of 2 drugs (DEC and albendazole) to all endemic villages. This study aimed primarily to estimate the Total and Government costs of two rounds of MDA conducted in Egypt in 2000 and 2001, the average cost per person treated, and the cost share of the different programme partners. METHODS: The Total costs reflect the overall annual costs of the MDA programme, and we defined Government costs as those expenditures made by the Egyptian government to develop, implement and sustain the MDA programmes. We used a generic protocol developed in coordination with the Emory Lymphatic Filariasis Support Center. Our study was concerned with all costs to the government, donors and other implementing parties. Cost data were retrospectively gathered from local, regional and national Ministry of Health and Population records. The total estimates for each governorate were based on data from a representative district for the governorate; these were combined with national programme data for a national estimate. RESULTS: The overall Total and Government costs for treating approximately 1,795,553 individuals living in all endemic villages in the year 2000 were US $3,181,000 and US$2,412,000, respectively. In 2001, the number of persons treated increased (29%) and the Total costs were US $3,109,000 while Government costs were US$2,331,000. In 2000, the average Total and Government costs per treated subject were US $1.77 and$1.34, respectively, however, these costs decreased to US $1.34 and$1.00, respectively in 2001. The coverage rate was 86.0% in 2000 and it increased to 88.0% in 2001. CONCLUSION: The Egyptian government provided 75.8% of all resources, as reflected in the Total cost estimates, and international agencies contributed the rest. Such data highlight both the commitment of the Egyptian government and the significance of the contributions of international bodies toward the LF elimination programme

Fault plane picking from focal mechanisms in reverse faulting stress: Application to the Mw6.9 Boumerdes (Algeria) earthquake sequence

Identification of the fault plane from two nodal planes of the focal mechanism is, in general, ambiguous. This problem is commonly solved using other constraints provided by tectonic, geological or seismic studies. In this paper, we evaluate the probability of identifying the fault plane using knowledge of stress field. We employ two alternative methods: (1) the slip angle method (SA), and (2) the highest instability method (IS). First, the efficiency of the methods was tested on synthetic data consisting of focal mechanisms compatible with a reverse stress regime. The tests revealed that the fraction of faults correctly picked by the IS method is higher than that of the SA method, particularly for large noise values. Second, the methods were applied to the aftershocks of the Boumerdes (Algeria) earthquake of May 21, 2003. This application showed that when taking into account the focal solutions for which the fault planes are determined using the IS method with a high probability, we observe consistency between the selected faults and the tectonics of the study area.The research was partially supported by Czech Science Foundation, grant no 22-10747S

Survey of the physico-chemical quality of the wastewaters of Biskra city rejected in Chabat Roba, Messdour and Wadi Z'ommor (Algeria)

The wastewaters of the agglomeration of Biskra (Southeast Algeria) are poured without treatment in three main dismissals that are Chabat Roba (1st site), Messdour (2nd site) and Wadi Z'ommor (3rd site). The pollution charge determined in the 1st site is the order of 157.76 ± 34.14 mg/L of O2 for the BOD5 (Biochemical Oxygen Demand in 5 days) of 457 ± 73.59 mg/L of O2 for the COD (Chemical Oxygen Demand) and 1109 ± 110.56 mg/L for the TSS (Total suspended Solids). In the 2nd site, the polluting charge is in average of 156 ± 29.72 mg/L of 'O2 for the BOD5, 430.76 ± 29.81 mg/L of O2 for the COD and 1157.92 ± 76 mg/L of O2 for the TSS. The 3rd site, the polluting charge is represented by 152.92 ± 27.76 mg/L of O2 of BOD5, 381.69 ± 70.03 mg/L of O2 of COD and by 1039 ±106.65 mg/L of O2 of TSS. The follow-up of these parameters in the three sites puts in evidence instability of the organic charge during seasons. The COD/BOD5 report equal 3 for the 1st site, this elevated value, watch that these waters are characterized by an inorganic pollution probably due to the industrial origin. With regard to the 2nd and 3rd sites, the COD/BOD5 report is between 3 and 2.5 for the first and between 2 and 2.50 for the second. The results defined the urban nature of the rejection poured in these sites.Key words: Wastewaters, Biskra, COD/BOD5 report, pollution charge, TSS

Three-dimensional Structure in a Supersonic Jet: Behavior near Centerline

The unsteady structure of a supersonic jet is highly three dimensional, though the mean flow is axisymmetric. In simulating a circular jet, the centerline represents a computational boundary. As such, spurious modes can be generated near centerline, unless special attention is given to the behavior of the 3D structure near the centerline. Improper treatment of the dependent variables near the centerline results in the solution diverging or being suitable only for small amplitude excitation. With a careful treatment of the centerline formation, no spurious mode is generated. The results show that a near-linear disturbance growth is obtained, as the linear stability theory indicates. At high levels of excitation, nonlinear development of disturbances is evident and saturation is reached downstream

Approximate logic synthesis: a survey

Approximate computing is an emerging paradigm that, by relaxing the requirement for full accuracy, offers benefits in terms of design area and power consumption. This paradigm is particularly attractive in applications where the underlying computation has inherent resilience to small errors. Such applications are abundant in many domains, including machine learning, computer vision, and signal processing. In circuit design, a major challenge is the capability to synthesize the approximate circuits automatically without manually relying on the expertise of designers. In this work, we review methods devised to synthesize approximate circuits, given their exact functionality and an approximability threshold. We summarize strategies for evaluating the error that circuit simplification can induce on the output, which guides synthesis techniques in choosing the circuit transformations that lead to the largest benefit for a given amount of induced error. We then review circuit simplification methods that operate at the gate or Boolean level, including those that leverage classical Boolean synthesis techniques to realize the approximations. We also summarize strategies that take high-level descriptions, such as C or behavioral Verilog, and synthesize approximate circuits from these descriptions