1,916 research outputs found

    OPTIMALISASI JARINGAN NIRKABEL DENGAN METODE RSSI DI AIKOM TERNATE

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    TThis study aims to optimize the wireless network from blind spots in the AIKOM Ternate environment. These blind spot areas make wireless network users (lecturers, staff, and students) uncomfortable because they have to get close to the nearest network source (access point (AP)) in order to access the internet or intranet network. With this wireless network optimization, the coverage area of ​​the wireless network is adjusted according to the need so that there are no more blind spots. The use of the Wireless Monitoring (Wirelessmon) application to detect the coverage area of ​​each installed AP, which is measured is the receive signal strength indicator (RSSI), including the determination of channel usage from each AP so as not to overlap in channel usage on each AP and the data rate that is experiencing increase and decrease according to the quality of the received signal. The results of this study indicate that after the optimization was carried out by installing the AP at five points. Optimization of the wireless network at the AIKOM Ternate campus was successful with RSSI -61dBm to -44dBm, RSSI was included in the very good category. It is recommended that RSSI measurements use more than one software so that comparisons are carried out, make comparisons of the received RSSI with the resulting throughput on different devices, and network administrators can use the results of this study but the use of devices with specifications that are different from those used in this study is suggested to perform retrieval of data so that the results are maximum.Penelitian ini bertujuan untuk optimalisasi jaringan nirkabel dari titik buta atau blind spot di lingkungan kampus AIKOM Ternate. Area-area titik buta ini membuat pengguna jaringan nirkabel (dosen, staf, dan mahasiswa) tidak nyaman dikarenakan harus mendekat ke sumber jaringan (access point (AP)) terdekat agar dapat mengakses jaringan internet ataupun intranet. Dengan optimalisasi jaringan nirkabel ini, area jangkauan jaringan nirkabel disesuikan dengan kebutuhan agar tidak ada lagi titik buta. Penggunaan aplikasi Wireless Monitoring (Wirelessmon) untuk mendeteksi area jangkauan dari setiap AP yang dipasang, yang diukur adalah receive signal strength indicator (RSSI), termasuk penentuan penggunaan kanal dari setiap AP agar tidak tumpang tindih atau overlapping dalam penggunaan kanal pada setiap AP dan data rate yang mengalami peningkatan dan penurunan menyesuaikan dengan kualitas sinyal yang diterima. Hasil penelitian ini menunjukkan setelah dilakukannya optimalisasi dengan memasang AP pada lima titik. Optimalisasi jaringan nirkabel pada kampus AIKOM Ternate berhasil dengan RSSI -61dBm sampai dengan -44dBm, RSSI termasuk dalam kategori sangat bagus (very good). Disarankan pengukuran RSSI menggunakan software lebih dari satu sehingga dilakukan perbandingan, melakukan perbandingan RSSI yang diterima dengan throughput yang dihasilkan pada perangkat yang berbeda, dan pengelola jaringan dapat menggunakan hasil penelitian ini akan tetapi penggunaan perangkat dengan spesifikasi yang berbeda dengan yang digunakan dalam penelitian ini maka disarankan untuk melakukan pengambilan data ulang agar hasilnya maksimal

    Ultrahigh Surface Area Three-Dimensional Porous Graphitic Carbon from Conjugated Polymeric Molecular Framework

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    Porous graphitic carbon is essential for many applications such as energy storage devices, catalysts, and sorbents. However, current graphitic carbons are limited by low conductivity, low surface area, and ineffective pore structure. Here we report a scalable synthesis of porous graphitic carbons using a conjugated polymeric molecular framework as precursor. The multivalent cross-linker and rigid conjugated framework help to maintain micro- and mesoporous structures, while promoting graphitization during carbonization and chemical activation. The above unique design results in a class of highly graphitic carbons at temperature as low as 800 ??C with record-high surface area (4073 m2 g-1), large pore volume (2.26 cm-3), and hierarchical pore architecture. Such carbons simultaneously exhibit electrical conductivity >3 times more than activated carbons, very high electrochemical activity at high mass loading, and high stability, as demonstrated by supercapacitors and lithium-sulfur batteries with excellent performance. Moreover, the synthesis can be readily tuned to make a broad range of graphitic carbons with desired structures and compositions for many applications.clos

    The NASA/IPAC Infrared Science Archive (IRSA): The Demo

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    This paper describes the services available at the NASA/IPAC Infrared Science Archive (IRSA). Currently there are nearly 250,000 data requests a month, taking advantage of IRSA's data repository which includes 660 million sources (60 catalogs), 10 million images (22 image sets; 10.4 TB) and over 30,000 spectra (7 spectroscopic datasets). These data are the science products of: The Two Micron All Sky Survey (2MASS), The Infrared Astronomical Satellite (IRAS), The Midcourse Space Experiment (MSX), The Submillimeter Wave Astronomy Satellite (SWAS), The Infrared Space Observatory (ISO), The Infrared Telescope in Space (IRTS), The Spitzer First Look Survey (FLS), Spitzer Legacy & Ancillary data, Spitzer Reserved Observations (ROC) and the Spitzer Space Telescope data. IRSA is also seamlessly interoperable with ten remote archives and services: GOODS, ISO, MAST, VizieR, DSS, NVSS, FIRST, HEASARC, NED and JPL, which help expand the available dataset wavelength range from X-ray to radio. The majority of IRSA's image collections are Simple Image Access (SIA) compliant and are available through the Virtual Observatory (VO) data mining tools. The IRSA demo includes IRSA's ¯ve main services: inventory service RADAR, catalog query service Gator, data fusion service OASIS, general search service for complex data collections Atlas, and IRSA's 2MASS Image data access services. IRSA's website is http://irsa.ipac.caltech.edu

    The Compartmentalisation of Phosphorylated Free Oligosaccharides in Cells from a CDG Ig Patient Reveals a Novel ER-to-Cytosol Translocation Process

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    BACKGROUND: Biosynthesis of the dolichol linked oligosaccharide (DLO) required for protein N-glycosylation starts on the cytoplasmic face of the ER to give Man(5)GlcNAc(2)-PP-dolichol, which then flips into the ER for further glycosylation yielding mature DLO (Glc(3)Man(9)GlcNAc(2)-PP-dolichol). After transfer of Glc(3)Man(9)GlcNAc(2) onto protein, dolichol-PP is recycled to dolichol-P and reused for DLO biosynthesis. Because de novo dolichol synthesis is slow, dolichol recycling is rate limiting for protein glycosylation. Immature DLO intermediates may also be recycled by pyrophosphatase-mediated cleavage to yield dolichol-P and phosphorylated oligosaccharides (fOSGN2-P). Here, we examine fOSGN2-P generation in cells from patients with type I Congenital Disorders of Glycosylation (CDG I) in which defects in the dolichol cycle cause accumulation of immature DLO intermediates and protein hypoglycosylation. METHODS AND PRINCIPAL FINDINGS: In EBV-transformed lymphoblastoid cells from CDG I patients and normal subjects a correlation exists between the quantities of metabolically radiolabeled fOSGN2-P and truncated DLO intermediates only when these two classes of compounds possess 7 or less hexose residues. Larger fOSGN2-P were difficult to detect despite an abundance of more fully mannosylated and glucosylated DLO. When CDG Ig cells, which accumulate Man(7)GlcNAc(2)-PP-dolichol, are permeabilised so that vesicular transport and protein synthesis are abolished, the DLO pool required for Man(7)GlcNAc(2)-P generation could be depleted by adding exogenous glycosylation acceptor peptide. Under conditions where a glycotripeptide and neutral free oligosaccharides remain predominantly in the lumen of the ER, Man(7)GlcNAc(2)-P appears in the cytosol without detectable generation of ER luminal Man(7)GlcNAc(2)-P. CONCLUSIONS AND SIGNIFICANCE: The DLO pools required for N-glycosylation and fOSGN2-P generation are functionally linked and this substantiates the hypothesis that pyrophosphatase-mediated cleavage of DLO intermediates yields recyclable dolichol-P. The kinetics of cytosolic fOSGN2-P generation from a luminally-generated DLO intermediate demonstrate the presence of a previously undetected ER-to-cytosol translocation process for either fOSGN2-P or DLO

    Associations of problematic internet use, weight-related self-stigma, and nomophobia with physical activity: findings from mainland China, Taiwan, and Malaysia

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    Insufficient physical activity is a common problem for university students because they may engage in sedentary lifestyle owing to excessive time spent on their smartphones and social media use. This may result in problematic internet use (PIU) and nomophobia (fear of not having a mobile phone). Moreover, prior evidence shows that weight-related self-stigma is an important factor contributing to low physical activity. Therefore, the present study examined the associations between PIU, nomophobia, and physical activity among university students across mainland China, Taiwan, and Malaysia. Participants (3135 mainland Chinese, 600 Taiwanese, and 622 Malaysian) completed the Bergen Social Media Addiction Scale (BSMAS), Smartphone Application-Based Addiction Scale (SABAS), Nomophobia Questionnaire (NMPQ), Weight Self-Stigma Questionnaire (WSSQ), and International Physical Activity Questionnaire Short Form (IPAQ-SF). The measurement invariance of the assessed questionnaires was supported across the three regions. The present findings analyzed using partial least squares structural equation modeling showed that (i) greater nomophobia was associated with higher levels of physical activity, (ii) greater weight-related self-stigma was associated with higher levels of physical activity, and (iii) greater nomophobia was associated with greater weight-related self-stigma. Although the present findings suggest the possibility that experiencing some level of nomophobia or weight-related self-stigma appears to help improve physical activity, it is not recommended that these be encouraged, but reducing PIU should be targeted as a means to improve physical activity

    Unassisted solar lignin valorisation using a compartmented photo-electro-biochemical cell

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    Lignin is a major component of lignocellulosic biomass. Although it is highly recalcitrant to break down, it is a very abundant natural source of valuable aromatic carbons. Thus, the effective valorisation of lignin is crucial for realising a sustainable biorefinery chain. Here, we report a compartmented photo-electro-biochemical system for unassisted, selective, and stable lignin valorisation, in which a TiO2 photocatalyst, an atomically dispersed Co-based electrocatalyst, and a biocatalyst (lignin peroxidase isozyme H8, horseradish peroxidase) are integrated, such that each system is separated using Nafion and cellulose membranes. This cell design enables lignin valorisation upon irradiation with sunlight without the need for any additional bias or sacrificial agent and allows the protection of the biocatalyst from enzymedamaging elements, such as reactive radicals, gas bubbles, and light. The photo-electrobiochemical system is able to catalyse lignin depolymerisation with a 98.7% selectivity and polymerisation with a 73.3% yield using coniferyl alcohol, a lignin monomer
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