479 research outputs found

    The Quadratic Assignment Problem : Some New Result and Generalization

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    The Quadratic assignment problem is a combinatorial problem ofdeciding the placement of facilities in specified locations in such a wayas to minimize an function expressed in terms of distances betweenlocations and flows between facilities. The approach presented in thispaper is to treat is as a large quadratic programming problem withinteger resfictions on the variables. The integer requirements areinitially relaxed, and the nearest feasible solutions in then sought.schemes for accomplishing this are described, and their applicability tomore general problems is discussed

    Eksistensi Dan Karakteristik Putusan Bersyarat Mahkamah Konstitusi

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    The result of this legal research show the existence of conditionally constitutional and conditionally unconstitutional decision in reviewing laws from 2003 to 2015, although that model of decision is not regulated in the positive law. There are 5 characteristics of conditionally constitutional decision, those are (1) Court gives interpretation or certain requirements in order to remain constitutional provisions tested throughout implemented according to the specified requirements of the Constitutional Court; (2) based on the rejected verdict; (3) a conditionally constitutional clause can be found only on the consideration of the Court, or can be found on the judgment and injunction; (4) conditionally constitutional decision require re-judicial review if the norm is not in line with the interpretation of the Constitutional Court; (5) encouraging legislative review. Regarding the conditionally unconstitutional decision, there are 4 characteristics, those are (1) the verdict certainly include a conditionally unconstitutional clause; (2) a conditionally verdict can be the meaning or interpretation of a norm, or give the terms of the norm is unconstitutional; (3) based on the granted verdict either partially or completely; (4) does not substantially different from the conditionally constitutional clause

    Isolation, Screening and Development of Local Bacterial Consortia With Azo Dyes Decolourising Capability

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    A total of 1540 bacterial isolates were isolated and screened for their ability to degrade selected azo dyes. Of these, nine isolates were chosen for further studies based on their ability to degrade a wide spectrum of dyes efficiently and rapidly. Several microbial consortia were developed and tested for their effectiveness. Overall the consortia were able to degrade 70 - 100% colour within 72 hours compared to 60 – 97% colour removed by individual isolates. A microbial consortium labelled C15 showed good growth in agitation culture but the colour removal was best in static culture with 80 - 100% colour removed in less than 72 hours. Based on the 16S rRNA sequencing, two of the bacterial isolates in C15 belong to the Chryseobacterium genus while the other one belongs to Flavobacterium genus

    Discriminator-based adversarial networks for knowledge graph completion

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    Knowledge graphs (KGs) inherently lack reasoning ability which limits their effectiveness for tasks such as question-answering and query expansion. KG embedding (KGE) is a predominant approach where proximity between relations and entities in the embedding space is used for reasoning over KGs. Most existing KGE approaches use structural information of triplets and disregard contextual information which could be crucial to learning long-term relations between entities. Moreover, KGE approaches mostly use discriminative models which require both positive and negative samples to learn a decision boundary. KGs, by contrast, contain only positive samples, necessitating that negative samples are generated by replacing the head/tail of predicates with randomly-chosen entities. They are thus usually irrational and easily discriminable from positive samples, which can prevent the learning of sufficiently robust classifiers. To address the shortcomings, we propose to learn contextualized KGE using pretrained adversarial networks. We assume multi-hop relational paths(mh-RPs) as textual sequences for competitively learning discriminator-based KGE against the negative mh-RP generator. We use a pre-trained ELECTRA model and feed it with relational paths. We employ a generator to corrupt randomly-chosen entities with plausible alternatives and a discriminator to predict whether an entity is corrupted or not. We perform experiments on multiple benchmark knowledge graphs and the results show that our proposed KG-ELECTRA model outperforms BERT in link prediction

    Investigation of multi-phase tubular permanent magnet linear generator for wave energy converters

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    In this article, an investigation into different magnetization topologies for a long stator tubular permanent magnet linear generator is performed through a comparison based on the cogging force disturbance, the power output, and the cost of the raw materials of the machines. The results obtained from finite element analysis simulation are compared with an existing linear generator described in [1]. To ensure accurate results, the generator developed in [1] is built with 3D CAD and simulated using the finite-element method, and the obtained results are verified with the source.The PRIMaRE project

    Analysis of particles size distribution on the agglomeration and shrinkage of alumina-zirconia compacts

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    The combination of Alumina and Zirconia has emerged as a promising ceramic structure for advance machine tool application. However, the particles of Alumina and Zirconia tend to agglomerate during mixture which affected shrinkage and dimension accuracy of the end product. This study focused on the analysis of the particle size of Alumina-Zirconia compacts and their relationship with the shrinkage and agglomerates. The particles size of single Alumina, Zirconia and ball-milled Alumina-Zirconia with 90-10 wt% ratio were examined by mastersizer. These powders then were compacted and sintered at 1400°C to examine their shrinkage. The results show that Alumina possesses larger particles size of 109.65 μm, which is 10 folds larger than Zirconia at 6.10 μm. When blended by ball mill, the Alumina�Zirconia particles were changed into 9.77 μm, showing that the ball mill to refine powder particles while reducing the risk of agglomeration. After sintering, the Alumina-Zirconia compacts were shrunk to maximum 9.56% when 75-25 wt% of Alumina-Zirconia. The combination of porosity, agglomerate and infiltration of zirconia between alumina grains were responsible for the shrinkage of Alumina-Zirconia compacts

    Fabrication and machining performance of ceramic cutting tool based on the Al2O3-ZrO2-Cr2O3 compositions

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    This study presents the cutting tool development of zirconia toughened alumina (ZTA) with chromia addition. The process used for its development is solid-state, in which the powders of Alumina (Al2O3), Zirconia (ZrO2) and Chromia (Cr2O3) were processed by a ball mill, com�pacted under a Cold Isostatic Press (CIP) and sintered at a constant temperature of 1400 ◦C with 9h soaking time. The initial study investigated the effect of Polyethylene glycol (PEG) as a binder, CIP and hardness of Al2O3-ZrO2 mixtures. The percentage composition between Al2O3 and ZrO2 was varied to choose the best for the highest mechanical performances determined by the density, porosity and properties analysis. The cutting tool that possessed the highest hardness and bending strength was selected the Al2O3-ZrO2 mixture was mixed 0.6 wt% Cr2O3 for machining trials within the cutting speed of 200–350m/min and constant feed rate and depth of cut of 0.150mm/rev and 0.5mm, respectively. The results of the ZTA mixed with Cr2O3 and combined with the ratio 80-20-0.6 wt% showed that the addition of 0.6 wt% PEG and a CIP pressure at 300 MPa and 60 s dwell time resulted maximum hardness and bending strength of 71.03 HRc and 856.02 MPa, respectively. The fabricated cutting tool was capable to reach 225 s tool life when machining AISI 1045 at a lower cutting speed of 200 m/min and higher feed rate of 0.150mm/rev

    Effect of sintering temperature on density, hardness and tool wear for alumina-zirconia cutting tool

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    Combination of alumina (Al2O3) and zirconia (ZrO2) as cutting tool have been established themselves as a dominant in ceramic category for dry machining. The mechanical properties of Al2O3-ZrO2 cutting tool were critically dependent on its density and hardness, which affected by the powder preparation and sintering processes. This paper present the effect of sintering temperature on density, hardness and tool wear of Al2O3-ZrO2 cutting tool. Specific composition of 80-90 wt% Al2O3 and 10-20 wt% ZrO2 powders were mixed and ball milled for 12 hours. These powders then were compacted in the form of RNGN120600 designated cutting tool by using manual hydraulic press before undergone secondary compaction by Cold Isostatic Press. The compacted powders then were sintered from 1200oC to 1400oC at constant 9 hours soaking time. For each sintered cutting tool, evaluation has been made based on the density and hardness. By using AISI 1045 as a workpiece material, the wear performance of the selected cutting tools were evaluated within 200-350 m/min cutting speeds, 0.1 mm/rev feed rate and 0.5 mm depth of cut. The results shows that the sintering temperature at 1400oC and 9 hours soaking time produced maximum relative density and hardness for 90 wt% Al2O3 and 10 wt% ZrO2 at 94.17% and 63.4 HRC respectively. Cutting tool contained with 80 wt% Al2O3 and 20 wt% ZrO2 contributed maximum relative density of 97% and hardness of 70.07 HRC. Maximum tool life recorded was 156s at 200 m/min cutting speed. Wear mechanisms of fabricated cutting tool dominated by the notch and flank wear at the early stage of machining and formation built up edge at the end of machining process

    A systematic review and meta-analysis of the diagnostic accuracy of pyruvate kinase M2 isoenzymatic assay in diagnosing colorectal cancer

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    BACKGROUND: Screening programmes exist in many countries for colorectal cancer. In recent years, there has been a drive for a non-invasive screening marker of higher sensitivity and specificity. Stool-based pyruvate kinase isoenzyme M2 (M2-PK) is one such biomarker under investigation. The aim of this systematic review and meta-analysis is to determine the diagnostic accuracy, sensitivity and specificity of M2-PK as a screening tool in colorectal cancer. METHODS: A literature search of Ovid Medline, EMBASE and Google Scholar was carried out. The search strategy was restricted to human subjects and studies published in English. Data on sensitivity and specificity were extracted and pooled. Statistical analysis was conducted using summary receiver operating characteristic (SROC) curve methodology. RESULTS: A total of eight studies were suitable for data synthesis and analysis. Our analysis showed a pooled sensitivity and specificity for M2-PK to be 79% (CI 73%–83%) and 80% (CI 73%–86%), respectively. The accuracy of M2-PK was 0.85(0.82–0.88). CONCLUSION: Faecal M2-PK assay has a relatively good sensitivity and specificity and high accuracy for screening colorectal cancer
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