53 research outputs found

    Analisis Penggantian Material Agregat Klas A Dan B Menjadi CTRB Paket Peningkatan Jalan Muara Teweh – Benangin Menggunakan Metode AASTHO’93

    Get PDF
    Roads are one of the infrastructures that will accelerate the growth and development of an area and open up socio-economic and cultural relations between regions. Along with the progress of infrastructure, the government has developed transportation facilities, namely the improvement of the Muara Teweh - Benangin road. In the Law of the Republic of Indonesia No.38 of 2004 concerning road infrastructure, roads have an important role in realizing the development of the nation's life. The improvement of the Muara Teweh - Benangin road used the flexible pavement thickness planning with the AASTHO 1993 method, the planned road life for flexible pavement was 20 years and the traffic growth factor was 6%. Sources of data used to plan flexible pavements were obtained from the Ministry of Public Works, Directorate General of Highways - National Executive Office VII. The data derived from the documentation is CBR data of subgrade and average traffic (LHR). These data are the basis most needed in planning a flexible pavement using the AASTHO method 1993. Based on the results of the calculation of the flexible pavement thickness planning using the AASTHO method, the following comparisons are obtained: (a) the total thickness of the surface layer HRS-Base / ATB 6 cm + HRS WC 3 cm, the upper foundation layer of class A = 15 cm, and the lower foundation layer of class B = 20 cm at a cost of Rp. 35,742,463,681, with an implementation time of 265 calendar days. (b) total surface layer thickness of HRS-Base / ATB 6 cm + HRS WC 3 cm, foundation layer CTRB 35 cm, at a cost of Rp. 34,278,182,220, - with execution time of 250 calendar days, resulting in a cost efficiency of Rp. 1,464,281,462, - with a difference of 15 calendar day

    Indoor temperature control and energy saving potential of split unit air conditioning system using fuzzy logic controller

    Get PDF
    Variable speed compressor offers a wider range of cooling capacity control according to the cooling load of the system. The on/off controller consumes larger energy as the compressor is always working at maximum speed despites the cooling load and continuously on and off to prevent from over cool the room. This study focused on the implementation of variable speed compressor to increase energy efficiency with better temperature control inside the room for split unit air conditioning system. The experiments are done at room temperature of 23 and 24°C with internal heat load of 500 and 1000 W. Monitoring system is applied to monitor the room temperature, energy consumption, energy saving and coefficient of performance. The proposed system indicates as much 37% of energy saving as compared to on/off controller

    Electrical treeing and partial discharge characteristics of silicone rubber filled with nitride and oxide based nanofillers

    Get PDF
    This article presents a study on electrical treeing performances with its associated partial discharge (PD) and the influence of filler concentration in silicone rubber (SiR) samples which are filled with silicon dioxide (SiO2) and silicon nitride (Si3N4) as nanofillers for electrical tree growth suppression. There are many researches on electrical treeing in SiR with SiO2 nanofillers but none of the publication have reported on Si3N4 nanofillers for suppression of the electrical tree growth. In this study, the treeing experiments were conducted by applying a fixed AC voltage of 10 kV and 12 kV at power frequency of 50 Hz on unfilled SiR, SiR/SiO2, and SiR/Si3N4 nanocomposites with different filler concentrations by 1, 3, and 5 weight percentage (wt%) and the electrical treeing parameters were observed with its correlated PD patterns. The outcome from this study found that the SiR/Si3N4 nanocomposites were able to withstand the electrical treeing better than the pure SiR or SiR/SiO2 nanocomposites. Furthermore, the increase in filler concentration improved the electrical tree performances of the nanocomposites. This finding suggests the Si3N4 can be used as filler in polymeric insulating materials for electrical tree inhibition. Meanwhile, the PD activity shows increment when the tree progresses thereby indicating correlation in both parameters which can be as key parameter for monitoring unseen electrical treeing in the opaque samples

    Biofilm reactors for industrial bioconversion processes: employing potential of enhanced reaction rates

    Get PDF
    This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms." As a result of biofilm formation, cell densities in the reactor increase and cell concentrations as high as 74 gL(-1 )can be achieved. The reactor configurations can be as simple as a batch reactor, continuous stirred tank reactor (CSTR), packed bed reactor (PBR), fluidized bed reactor (FBR), airlift reactor (ALR), upflow anaerobic sludge blanket (UASB) reactor, or any other suitable configuration. In UASB granular biofilm particles are used. This article demonstrates that reactor productivities in these reactors have been superior to any other reactor types. This article describes production of ethanol, butanol, lactic acid, acetic acid/vinegar, succinic acid, and fumaric acid in addition to wastewater treatment in the biofilm reactors. As the title suggests, biofilm reactors have high potential to be employed in biotechnology/bioconversion industry for viable economic reasons. In this article, various reactor types have been compared for the above bioconversion processes

    High-throughput screening of cellulase F mutants from multiplexed plasmid sets using an automated plate assay on a functional proteomic robotic workcell

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The field of plasmid-based functional proteomics requires the rapid assay of proteins expressed from plasmid libraries. Automation is essential since large sets of mutant open reading frames are being cloned for evaluation. To date no integrated automated platform is available to carry out the entire process including production of plasmid libraries, expression of cloned genes, and functional testing of expressed proteins.</p> <p>Results</p> <p>We used a functional proteomic assay in a multiplexed setting on an integrated plasmid-based robotic workcell for high-throughput screening of mutants of cellulase F, an endoglucanase from the anaerobic fungus <it>Orpinomyces </it>PC-2. This allowed us to identify plasmids containing optimized clones expressing mutants with improved activity at lower pH. A plasmid library of mutagenized clones of the <it>celF </it>gene with targeted variations in the last four codons was constructed by site-directed PCR mutagenesis and transformed into <it>Escherichia coli</it>. A robotic picker integrated into the workcell was used to inoculate medium in a 96-well deep well plate, combining the transformants into a multiplexed set in each well, and the plate was incubated on the workcell. Plasmids were prepared from the multiplexed culture on the liquid handler component of the workcell and used for <it>in vitro </it>transcription/translation. The multiplexed expressed recombinant proteins were screened for improved activity and stability in an azo-carboxymethylcellulose plate assay. The multiplexed wells containing mutants with improved activity were identified and linked back to the corresponding multiplexed cultures stored in glycerol. Spread plates were prepared from the glycerol stocks and the workcell was used to pick single colonies from the spread plates, prepare plasmid, produce recombinant protein, and assay for activity. The screening assay and subsequent deconvolution of the multiplexed wells resulted in identification of improved CelF mutants and corresponding optimized clones in expression-ready plasmids.</p> <p>Conclusion</p> <p>The multiplex method using an integrated automated platform for high-throughput screening in a functional proteomic assay allows rapid identification of plasmids containing optimized clones ready for use in subsequent applications including transformations to produce improved strains or cell lines.</p

    Random UV-C mutagenesis of Scheffersomyces (formerly Pichia) stipitis NRRL Y-7124 to improve anaerobic growth on lignocellulosic sugars

    Get PDF
    Scheffersomyces (formerly Pichia) stipitis NRRL Y-7124 was mutagenized using UV-C irradiation to produce yeast strains for anaerobic conversion of lignocellulosic sugars to ethanol. UV-C irradiation potentially produces large numbers of random mutations broadly and uniformly over the whole genome to generate unique strains. Wild-type cultures of S. stipitis NRRL Y-7124 were subjected to UV-C (234 nm) irradiation targeted at approximately 40% cell survival. When surviving cells were selected in sufficient numbers via automated plating strategies and cultured anaerobically on xylose medium for 5 months at 28°C, five novel mutagenized S. stipitis strains were obtained. Variable number tandem repeat analysis revealed that mutations had occurred in the genome, which may have produced genes that allowed the anaerobic utilization of xylose. The mutagenized strains were capable of growing anaerobically on xylose/glucose substrate with higher ethanol production during 250- to 500-h growth than a Saccharomyces cerevisiae yeast strain that is the standard for industrial fuel ethanol production. The S. stipitis strains resulting from this intense multigene mutagenesis strategy have potential application in industrial fuel ethanol production from lignocellulosic hydrolysates

    Prednisolone versus placebo addition in the treatment of patients with recent-onset psychotic disorder: a trial design

    Get PDF
    BACKGROUND: The symptom severity of a substantial group of schizophrenia patients (30-40%) does not improve through pharmacotherapy with antipsychotic medication, indicating a clear need for new treatment options to improve schizophrenia outcome. Meta-analyses, genetic studies, randomized controlled trials, and post-mortem studies suggest that immune dysregulation plays a role in the pathophysiology of schizophrenia. Some anti-inflammatory drugs have shown beneficial effects on the symptom severity of schizophrenia patients. Corticosteroids are effective in various chronic inflammatory and autoimmune disorders. Prednisolone, a potent glucocorticosteroid, has minor mineral-corticosteroid potencies and can adequately pass the blood-brain barrier
    corecore