235 research outputs found

    Inventarisasi Tanaman Peneduh Jalan Penjerap Timbal di Purwokerto

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    Tanaman peneduh jalan adalah tanaman yang berada di tepi jalan. Tanaman peneduh jalan memiliki dua fungsi yaitu sebagai estetika dan ekologis. Salah satu fungsi ekologis tanaman peneduh jalan adalah mengakumulasi bahan pencemar. Jenis pencemaran yang memerlukan penanganan secara sistematis dan komprehensif adalah pencemaran timbal (Pb). Pb banyak dihasilkan oleh aktivitas pembakaran bahan bakar minyak kendaraan bermotor. Jenis tanaman peneduh jalan yang berpotensi mengakumulasi Pb belum tereksplorasi sehingga dilakukan riset yang dapat menghasilkan database jenis spesies yang mampu mengurangi Pb di lingkungan. Tujuan penelitian adalah menginventarisasi jenis tanaman peneduh jalan penjerap Pb. Manfaat penelitian adalah mendapatkan jenis tanaman peneduh jalan yang berpotensi penjerap Pb. Metode penelitian yang digunakan adalah survai di 8 (delapan) jalan di wilayah Purwokerto. Sampel daun tanaman peneduh jalan diambil secara acak terpilih di sepanjang jalan tersebut. Hasil penelitian menunjukkan jenis-jenis tanaman peneduh jalan yang berpotensi menjerap Pb adalah Glodogan (Polyalthea longifolia), Angsana (Pterocarpus indicus), Filicium (Filicium decipiends), Ketapang (Terminalia catappa), Beringin (Ficus benjamina), Kupu-kupu (Bauhinia tomentosa), Puspa (Schima wallichii), Kenari (Canarium ovatum) dan Genitu (Chrysophyllum cainito)

    Enriching Chinese-English Bilingual Education with Translanguaging: an Australian case-study

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    Abstract for presentation at ALAA2016/ALS2016 joint day

    Professional development of sessional academic staff in Australian universities

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    Since the 1970s the use of sessional academics has intensified. Sessional academics perform a critical role within the university and make a strong contribution to the quality of teaching outcomes. However, the management of these staff and training and development programs for them are under-developed. Given the increasing number of sessional academics, and the contributions of sessional academics to university work, it is time to recognize how important sessional academics have become and to research how these sessional academics are supported in their duties. The research project identifies and explains training and development issues facing sessional academic staff. The review of literature highlights the increasing casualization of the academic workforce and a training deficit situation. The research design is a mixed method case study involving a group of ten sessional academics, two full-time academics and their managers at X University Y Campus'. It covers the stories of their differing experiences of professional development, and explores their concerns and feelings in detail. Documentary data are gathered and analyzed in order to triangulate data gathered from interviews. The documents form a valuable source of information about sessional academics' purported training and development opportunities. The study contributes to the literature about sessional academics' training and development opportunities and provides suggestions for a model for improved support and training for sessional academic staff If acted on, the suggestions and model will provide sessional academics opportunities to develop professionally, to improve their own practice and, indirectly, to improve the achievement of their students. The study has the potential not only to improve the skill level of sessional academic staff at the University studied, but also implies benefits to universities, students and our community.</p

    Modelling and autoresonant control design of ultrasonically assisted drilling applications

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    The target of the research is to employ the autoresonant control technique in order to maintain the nonlinear oscillation mode at resonance (i.e. ultrasonic vibration at the tip of a drill bit at a constant level) during vibro-impact process. Numerical simulations and experiments have been executed. A simplified Matlab-Simulink model which simulates the ultrasonically assisted machining process consists of two parts. The first part represents an ultrasonic transducer that contains a piezoelectric transducer and a 2-step concentrator (waveguide). The second part reflects the applied load to the ultrasonic transducer due to the vibro-impact process. Parameters of the numerical models have been established based on experimental measurements and the model validity has been confirmed through experiments performed on an electromechanical ultrasonic transducer. The model of the ultrasonic transducer together with the model of the applied load was supplemented with a model of the autoresonant control system. The autoresonant control intends to provide the possibility of self-tuning and self-adaptation mechanism for an ultrasonic transducer to maintain its resonant regime of oscillations automatically by means of positive feedback. This is done through a signal to be controlled (please refer to Figure 7.2 and Figure 7.3) transformation and amplification. In order to examine the effectiveness and the efficiency of the autoresonant control system, three control strategies have been employed depending on the attributes of the signals to be controlled . Mechanical feedback control uses a displacement signal at the end of the 2nd step of the ultrasonic transducer. The other two control strategies are current feedback control and power feedback control. Current feedback control employs the electrical current flowing through the piezoceramic rings (piezoelectric transducer) as the signal to be controlled while power feedback control takes into account both the electrical current and the power of the ultrasonic transducer. Comparison of the results of the ultrasonic vibrating system excitation with different control strategies is presented. It should be noted that during numerical simulation the tool effect is not considered due to the complexity of a drill bit creates during the Ultrasonically Assisted Drilling (UAD) process. An effective autoresonant control system was developed and manufactured for machining experiments. Experiments on Ultrasonically Assisted Drilling (UAD) have been performed to validate and compare with the numerical results. Two sizes of drill bits with diameters 3mm and 6mm were applied in combination with three autoresonant control strategies. These were executed during drilling aluminium alloys with one fixed rotational speed associated with several different feed rates. Vibration levels, control efforts, feed force reduction were monitored during experiments. Holes quality and surface finish examinations supplement analysis of the autoresonant control results. In addition, another interesting research on the investigation of the universal matchbox (transformer) has been carried out. Introducing a varying air gap between two ferrite cores allows the optimization of the ultrasonic vibrating system, in terms of the vibration level, effective matchbox inductance, voltage and current level, phase difference between voltage and current, supplied active power etc (more details please refer to Appendix I)

    Airborne Microbial Aerosol Detection by Combining Single Particle Mass Spectrometry and a Fluorescent Aerosol Particle Sizer

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    Detection methods for microbiological aerosols based on single particle mass spectrometry (SPAMS) and a fluorescent aerosol particle sizer (FLAPS) have been developed progressively. However, they encounter interference and inefficiency issues. By merging FLAPS and SPAMS technologies, the majority of inorganic ambient aerosols may be eliminated by the FLAPS, thus resolving SPAMS’ large data volume. SPAMS, on the other hand, may eliminate the secondary fluorescence interference that plagues the FLAPS. With the addition of the enhanced machine learning classifier, it is possible to extract microbial aerosol signals more precisely. In this work, a FLAPS–SPAMS instrument and a Random Forest classifier based on Kendall’s correlation expansion training set approach were built. In addition to analyzing the outdoor microbial proportions, the interference components of non-microbial fluorescent particles were also examined. Results indicate that the fraction of outdoor microbial aerosols in fluorescent particles is 25.72% or roughly 2.57% of total particles. Traditional ART-2A algorithm and semi-empirical feature clustering approaches were used to identify the interference categories of abiotic fluorescent particles, which were mostly constituted of EC/OC, LPG/LNG exhaust, heavy metal organics, nicotine, vinylpyridine, polycyclic aromatic hydrocarbons (PAHs), and polymers, accounting for 68.51% of fluorescent particles

    Results of quality assessment by Cochrane risk of bias.

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    <p>a. each risk of bias item presented as percentages across all included studies. b. each risk of bias item for each included study.</p

    TEM analyses of peanut seeds after 4 days.

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    <p>a) seed coat of NZVI-40, b) seed coat of CK, c) peanut of NZVI-40, and d) peanut of CK. The dark arrows show small clusters of NZVI particles. NZVI was indicated by dark arrow.</p

    Characteristics of the included studies.

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    <p>Characteristics of the included studies.</p

    Effects of NZVI treatments on peanut plant growth.

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    <p>a) photograph of peanut plants in containers after 13 days, b) photograph of peanut plants after 18 days, c) length of the stems of the peanut plants, d) weight of the peanut plants, e) TEM image of root tissue of NZVI-40, and f) TEM image of root tissue of CK. Different letters show significant differences (pâ©˝0.05) and bars represent the standard error of treatments (n = 4). NZVI was indicated by dark arrow.</p
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