1,253 research outputs found

    Performance evaluation of optical attocells configuration in an indoor visible light communication

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    Visible light communication VLC is deemed as futuristic technology applied for both illumination and data communication due to the low-cost energy consumption, long life expectancy, huge bandwidth, and high security compared to radio frequency RF. Uncovered area, minimum signal-to-noise ratio (SNR) and received power results from the non-uniform distribution of small base stations (i.e. Optical attocells) in the room. In this paper, the researchers propose a new LEDs distribution of five optical attocells configuration model in order to optimize the received power distribution and SNR at the center of the room for indoor VLC system. The optical attocells configuration in terms of received power to fill the uncovered area at the center of the room has been investigated. The simulation results showed that the proposed attocells configuration saved 24.9% of the transmitted power. Besides that, the whole room was covered uniformly. As a result, the received power and SNR are improved

    Effect of nano-CaCO3 on compressive strength development of high volume fly ash mortars and concretes

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    This paper presents the experimental results on the effect of nano-CaCO3 on compressive strength development of mortars and concretes containing high volume fly ash (HVFA). The effect of various nano-CaCO3 contents such as 1, 2, 3and 4% (wt.%) as partial replacement of cement on the compressive strength of mortars are evaluated in the first part. The nano-CaCO3 content which exhibited the highest compressive strength above is used in high volume fly ash mortars and concretes containing 40% and 60% class F fly ash. The results show that among four different nano-CaCO3contents, the addition of 1% nano-CaCO3 increased the compressive strength of mortars and concretes. The addition of1% nano-CaCO3 also increases the early age and 28 days compressive strengths of HVFA mortars and concretes. The X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analysis results also support the above findings

    ANALISIS FAKTOR PENYEBAB DAN STRATEGI PENGENDALIAN ALIH FUNGSI SAWAH MENJADI PERUMAHAN DAN DAMPAKNYA TERHADAP LINGKUNGAN DI KOTA BENGKULU

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    Tujuan penelitian ini adalah untuk mengetahui faktor penyebab, strategi pengendalian, dan dampaknya terhadap lingkunga alih fungsi lahan sawah menjadi perumahan di Kota Bengkulu. Penelitian dilakukan pada Oktober sampai dengan November 2019 di Kota Bengkulu, Provinsi Bengkulu. Estimasi faktor-faktor yang mempengaruhi petani dalam mengalih fungsikan lahan sawah digunakan analisis regresi logistik. Dampak alihfungsi sawah terhadap lingkungan maka dilakukan analisis deskriptif. Sedangkan strategi penataan alih fungsi lahan digunakan analisis SWOT. Hasil penelitian menunjukkan bahwa j umlah tanggungan keluarga, kendala irigasi dan harga jual sawah berpengaruh nyata terhadap peluang terjadinya alih fungsi lahan . Semakin tinggi jumlah tanggungan keluarga, kendala irigasi dan harga jual sawah maka semakin tinggi kecenderungan petani untuk melakukan alih fungsi lahan sawah menjadi perumahan. Posisi pengendalian alih fungsi lahan pertanian sawah berada pada kuandran III yaitu posisi dengan strategi WO yaitu pemanfaatan peluang yang ada dan meminimalkan kelemahan yang ada. Sebanyak 70,75% responden beranggapan bahwa alih fungsi lahan sawah menjadi perumahan berdampak negatif terhadap lingkungan dengan rata -rata jawaban 3,54 yang tergolong setuju

    Studi Optimasi Kinerja Sucker Rod Pump pada Sumur A-1, A-2,Z-1, dan Z-2 Menggunakan Perangkat Lunak Prosper

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    Sucker rod pump is a type of artificial lift methods are often used to date. Sucker rod pump suitablefor wells with low productivity, as well as the relative ease in operation and treatment becausepeople in the field have been much acquainted with this type of pump. Sucker rod pump workingprinciple or often called beam pumping up and down movement harnesses from the plunger topush the fluid reservoir to the surface. Optimization sucker rod pump performance can beperformed using software prosper

    Hubungan Antara Kecerdasan Emosi Dan Efikasi Diri Akademik Pada Siswa Kelas XI Smk Bina Wisata Lembang

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    Tujuan dalam penelitian ini adalah untuk mengetahui secara empirik hubungan antara kecerdasan emosi dan efikasi diri akademik pada siswa di SMK Bina Wisata Lembang. Metode penelitian yang digunakan adalah metode kuantitatif. Sampel diambil berdasarkan teknik cluster random sampling. Subjek penelitian berjumlah 170 orang siswa kelas XI SMK Bina Wisata Lembang yang terdiri dari 5 kelas dari berbagai jurusan. Alat ukur yang digunakan yaitu skala Likert dengan empat pilihan respon jawaban. Koefisien reliabilitas skala kecerdasan emosi adalah 0,933 dengan 37 aitem, sedangkan koefisien reliabilitas skala efikasi diri akademik adalah 0,951 dengan 34 aitem. Skor menunjukkan bahwa kecerdasan emosi dan efikasi diri akademik subjek berada pada kategori yang tinggi. Berdasarkan hasil analisis statistik menggunakan analisis regresi sederhana, didapatkan koefisien korelasi 0,496 dengan p=0,00 (p<0,01). Nilai koefisien korelasi menunjukkan terdapat hubungan positif yang signifikan, antara kecerdasan emosi dan efikasi diri akademik. Nilai koefisien determinasi sebesar 0,246, artinya kecerdasan emosi memberikan pengaruh sebesar 24,6% pada efikasi diri akademik. Sebesar 76,4% pengaruh terhadap efikasi diri akademik dapat disebabkan oleh faktor status sosial, sifat tugas, dan informasi kemampuan diri

    Management and Complications of Arnold Chiari Hydrocephalus at Tertiary Health Care Center

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    Objective: to investigate the role of CT and MRI in diagnosis of Arnold chiari malformation of hydrocephalus and its treatment with VP shunt along with complications. Study Design: Prospective study Place and duration: Department of Neurosurgery, DG Khan Medical College from May 4, 2018 to May 4, 2019. Methodology: Fifty patients of congenital hydrocephalus who were not treated previously were selected. Detailed history about disease and clinical examination of patients was performed. Follow ups were done at neurosurgery OPD. SPSS software for data analysis was used and mean ± SD, frequency and percentages were calculated for variables. P value ≤0.05 was considered as significant. Results: Treatment in case of congenital hydrocephalus as VP shunt, intra-aneurysmal coiling, excision of meningomyelocele with VP shunt and suboccipital craniectomy + upper cervical laminectomy (scucl) were observed as 10%, 6%, 8% and 8% respectively.  Twelve percent of patients were not treated. Conclusion: CT and MRI are the main diagnostic tools for diagnosis of Arnold chiari malformation and VP shunt is the treatment of choice. Among complications of VP shunt infection of shunt and shunt block are the main complications

    Ultrasonic Waves Assisted Synthesis of Curcuminoids Based on 3-Methylacetylacetone and in Situ Synthesis of Gold Nanoparticles Capped with Curcuminoids

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    Ultrasonic irradiation was used to induce the Knuevenagle reaction between aromatic aldehydes and 3-methylacetylacetone to synthesize curcumin analogues with moderate to good yields. The structures of the compounds were established by elemental analysis and from their mass and 1HNMR spectra. In situ curcumin-gold nanoparticles were synthesized. The solutions of the prepared nanoparticles have purple to deep-red colors and their UV-vis spectra were characterized by the Surface Plasmon Resonance bands within the range 538-554 nanometer
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