Improvement of wind turbine lightning receptor

Lightning receptor is a device attached to a wind turbine blade that will attract and assist lightning current flow to the ground. However, lightning does not necessarily strike it, instead the other part of the wind turbine is still been stroked by lightning eventually leading to catastrophe damage of the wind turbine. This research is aimed to develop a needle-type receptor on a wind turbine blade for lightning protection system (LPS). Other than that, this project is aimed to study the practical parameters of lightning protection system, including the relation between receptor size and electric field strength. The receptors were designed by three different disk diameters of 0.2 m, 0.5 m and 0.8 m. In 0.2m receptor diameter, the comparison between the numbers and length of needles presents that 32 number of needles and 0.3m length of needles can attract a higher electrical field than others. Each disk diameter consists of different needles number and length. Finite Element Method (FEM) has used for this research, the proper dimensions and shapes of receptors simulated by suggesting the minimum and maximum electric field that accumulates around receptors. The simulation study plays an active role in understanding and designing the receptor of wind turbines for an effective lightning protection system (LPS), but it requires a validation under actual condition

Experimental and computational studies of furan derivatives in corrosion inhibition of mild steel

Corrosion of metals causes huge losses in resources and industrial equipment especially when they are exposed to acidic medium. One of the most practical methods to control the corrosion of a metal is the use of heterocyclic organic compounds as corrosion inhibitors. A large number of organic compounds have been investigated as corrosion inhibitors; however, only few furan derivatives have been studied. In this study, eighteen furan derivatives were investigated as corrosion inhibitors for mild steel in hydrochloric acid. Furan derivatives were chosen as promising corrosion inhibitors based on their heterocyclic structures. The inhibition performance and corrosion process were studied using several techniques, namely potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), weight loss, adsorption isotherms, field emission scanning electron microscopy (FESEM), and X-ray photoelectron spectroscopy (XPS). The results showed the ability of furan derivatives to inhibit corrosion of mild steel in acidic solution and some of them showed high inhibition efficiencies of up to 96%. In addition, quantum chemical calculations using density functional theory (DFT) were used to evaluate inhibition performances of selected inhibitors and investigate active sites on the inhibitor molecule. The results showed the ability of DFT to explain the inhibition performances and assign the active sites of the inhibitors. Furthermore, several quantitative structure–activity relationship (QSAR) procedures were applied such as genetic algorithm-partial least square (GA-PLS), interval-PLS (IPLS), penalized multiple linear regression (PMLR) using ridge, LASSO and elastic net and sparse multiple linear regression (SMLR). The results showed that PMLR based on LASSO and elastic net, and SMLR based on elastic net were useful for the regression of the inhibition efficiencies. In conclusion, the quantum calculations and QSAR procedures complement the experimental investigations and interpret experimental results

STRATEGI KUA KECAMATAN BANGUNTAPAN DALAM MENGATASI PERKAWINAN ANAK DI KAPANEWON BANGUNTAPAN KABUPATEN BANTUL DAERAH ISTIMEWA YOGYAKARTA

Abstract: The research aimed to describe the issue of child marriage in the Banguntapan sub-district and the strategies used by the KUA (Islamic Religious Affairs Office) of the Banguntapan sub-district in addressing this issue. The research was descriptive and analytical and was conducted at the KUA of the Banguntapan sub-district. Data was collected through interviews and documentation. Primary data were obtained from interviews with the KUA of the Banguntapan sub-district, while secondary data was obtained from books, scholarly articles, laws, and other relevant documents. The research results showed an increase in child marriage in Kapanewon Banguntapan. The strategies used by the KUA of the Banguntapan sub-district to address this issue include prevention and guidance. The KUA of Banguntapan sub-district implemented prevention strategies by enforcing the minimum age for marriage as per the Marriage Law, participating in educational activities on the dangers of child marriage within the community, such as in Majelis Ta’lim and Program Keluarga Harapan, and providing pre-marriage guidance for teenagers in schools. If child marriage cannot be prevented, the KUA of the Banguntapan sub-district guides to ensure that the families from child marriage can achieve the goals of a peaceful, loving, and compassionate marriage.Keywords: child marriage, KUA strategy, maṣlaḥah mursala

Experimental and quantum chemical calculations on corrosion inhibition of mild steel by two furan derivatives

Two furan derivatives namely 5-methylfurfurylamine (MFA) and furfurylamine (FAM) were investigated as corrosion inhibitors for mild steel in 1 M HCl. The corrosion inhibition efficiencies (IE) were measured at 0.005M of the inhibitors using electrochemical potentiodynamic polarization measurements. The studied furan derivatives inhibit mild steel corrosion in acidic medium. The MFA shows higher inhibition efficiency of 84.77% compared to FAM of 41.75%. Quantum chemical calculations were performed at the B3LYP/6-311++G(d,p) level of density functional theory (DFT). Several quantum parameters were calculated to study the correlation between the molecular structures and the corrosion inhibition performance of the inhibitors. The MFA inhibitor shows higher HOMO energy, softness (S), fraction of electrons transferred (ΔN), and lower energy gap (ΔE) compared to the FAM. This result indicates a better corrosion inhibition performance of the MFA inhibitor. The results show that the calculated values of the quantum parameters using DFT calculations are consistent with the experimental findings

PERAN MAJELIS PEMBERDAYAAN MASYARAKAT (MPM) MUHAMMADIYAH LAMPUNG DALAM MENINGKATKAN KESEJAHTERAAN MASYARAKAT (Studi Pada Komunitas Petani Organik Berkemajuan di Kec. Tegineneng, Kab. Pesawaran, Prov. Lampung

ABSTRAK Pemberdayaan masyarakat adalah upaya untuk mengembangkan kemampuan masyarakat dalam memenuhi kebutuhan hidupnya, menjauhkannya jadi jurang kemiskinan dan meraih kesejahteraan. September 2019, menurut data BPS kemiskinan di Lampung mencapai 1,04 juta orang. Perlu upaya memberdayakan masyarakat untuk meningkatkan kesejahteraan masyarakat. Majelis Pemberdayaan Muhammadiyah adalah lembaga yang bergerak untuk memberdayakan masyarakat. Tujuan dari penelitian ini adalah untuk menjelaskan bagaimana Peran Majelis Pemberdayaan Masyarakat (MPM) Muhammadiyah Lampung Dalam Meningkatkan Kesejahteraan Masyarakat. (Studi Pada Komunitas Petani Organik Berkemajuan Di Kec. Tegineneng, kab. Pesawaran, prov. Lampung). Untuk mengetahui pandangan ekonomi Islam tentang peran Majelis Pemberdayaan Masyarakat (MPM) Muhammadiyah Lampung dalam meningkatkan kesejahteraan masyaraka. Jenis penelitian adalah penelitian deskriptif kualitatif. Data yang digunakan adalah data menggunakan data primer dari hasil wawancara dengan responden. Teknik analisis data setelah data terkumpul baik dari lapangan maupun pustaka, maka selanjutnya menganalisis data sesuai dengan permasalahannya. Data tersebut dianalisis dengan menggunakan analisis data yang bersifat kualitatif, yaitu metode kualitatif sebagai prosedur penelitian yang menghasilkan data deskriptif berupa kata-kata tertulis maupun lisan dari orang-orang yang diamati. Adapun metode berfikir yang dipakai pada penelitian ini adalah metode deduktif. Hasil penelitian diperoleh bahwa Majelis Pemberdayaan Masyarakat (MPM) Muhammadiyah Lampung telah memberikan dampak positif dalam meningkatkan kesejahteraan masyarakat. Dampak tersebut bisa dilihat dari meningkatnya pendapatan, terpenuhinya kebutuhan primer, kemudahan dalam akses kesehatan, kemudahan dalam memenuhi biaya pendidikan, dan terlaksananya ibadah zakat maal para petani yang tergabung dalam Komunitas Petani Organik Berkemajuan. Pemberdayaan yang dilakukan oleh Majelis Pemberdayaan Masyarakat (MPM) Muhammadiyah Lampung sudah sesuai dengan prinsip-prinsip ekonomi Islam. Kesesuaian praktik dan teori yang dibangun dari teologi surat Al-Mauun, memberikan dampak yang baik kepada semangat para petani yang ada dalam iii Komunitas Petani Organik Berkemajuan dalam menjalankan kegiatan pertaniannya. Para petani ini bukan sekedar semangat untuk mencari keuntungan materi saja tetapi juga mencari keberkahan, pahala dan ridho dari Allah. Kata kunci : Pemberdayaan Masyarakat, Majelis Pemberdayaan Masyarakat, Kesejahteraan

The Relationship between Anxiety, Stress, and Working Memory Capacity

This study designed a quantitative research to identify the relationship between anxiety, stress, and working memory capacity (WMC). The study aims to test the differences between anxiety levels in WMC and the correlation between stress and WMC. The research used a quasiexperiment method where 16 participants were assigned into online assessments to measure anxiety and stress levels, then, they were invited to attend face-to-face task to measure WMC. The study adopted the Beck Anxiety Inventory (BAI) assessment to measure anxiety, the Perceived Stress Scale (PSS-10) assessment to measure stress, and the Operation Span Task to measure WMC. Analysis of the collected data demonstrated that there are no significant differences between anxiety levels in WMC, also, there is no significant correlation between stress and WMC. Overall, the result indicates that anxiety and stress do not influence the capacity of WM. In fact, the research’s findings are opposite to pervious research that have shown a decline in WMC due to high anxiety and stress. For this reason, this experimental research emphasis on the need for further studies of this relationship. However, this study has some limitations in terms of sample size, the variety of WMC task, and the availability of appropriate location

Penyusunan Zonasi Kawasan Pertambangan Di Kabupaten Magetan Berdasarkan Aplikasi Sistem Informasi Geografis Dengan Metode Pertampalan

Magetan has resources mineral potential of non-metallic minerals and rocks. The mineral variety is a mineral which relates to the people livelihood because it necessary for infrastructure development. There is no mining area zoning until now and it can be used to optimize the management and utilization of potential resources. In Magetan, mining area zoning was carried out by giving weights and assessments to the determining parameters which was conducted by patch method and it utilized Geographic Information System.  So, the result of mining area zoning could be grouped into three zones. They were a zone could be granted a mining permit, a zone could be granted a conditional mining permit and a zone could not be granted a mining permit. Determining parameters for mining area zoning were land height, disaster vulnerability, groundwater, river borders, lakes and irrigation buildings, springs, forests and protected areas, agricultural land and cultivation areas, settlements, cultural heritage, tourism and district strategic areas, and land slope. The result of potential resources identification was carried out by analyzing Magetan geological map which was obtained potential resources, like andesite, pumice breccia, sandstone, siltstone and basalt. The zoning of Magetan mining area is a zone could bne granted a mining permit and the area was 9,914.507 Ha or about 14% in a percentage of the area, a zone could be granted a conditional mining permit covering an area of 20,748.29 Ha or about 30% and a zone unable to be granted a mining permit covering an area of 39,296.08 Ha or about 56% of the total area of Magetan.Zonasi Kawasan Pertambangan di Kabupaten Magetan dilakukan dengan memberikan pembobotan dan penilaian pada parameter penentu yang dikerjakan dengan metode pertampalan dengan memanfaatkan Sistem Informasi Geografis (SIG). Sehingga hasil dari Zonasi Kawasan Pertambangan dapat dikelompokan menjadi Zona Dapat Diberi Izin Pertambangan, Zona Dapat Diberi Izin Pertambangan Bersyarat dan Zona Tidak Dapat Diberi Izin Pertambangan. Parameter penentu Zonasi Kawasan Pertambangan tersebut adalah ketinggian lahan, kerawanan bencana, air tanah, sempadan sungai, danau dan bangunan irigasi, mata air, hutan dan kawasan lindung, lahan pertanian dan kawasan budidaya, pemukiman,cagar budaya, pariwisata dan kawasan strategis kabupaten, dan kemiringan lahan. Dari hasil identifikasi potensi sumberdaya yang dilakukan dengan menganalisa peta geologi Kabupaten Magetan didapat potensi sumberdaya antara lain pasir, belerang, pasir batu, trass dan andesit,. Sedangkan untuk hasil Zonasi Kawasan Pertambangan Kabupaten Magetan yaitu Zona Dapat Diberi Izin Pertambangan seluas 9.914,507 Ha atau sekitar 14 % dalam presentase luas, Zona Dapat Diberi Izin Pertambangan Bersyarat seluas 20.748,29 Ha atau sekitar 30 % dan Zona Tidak Dapat Diberi Izin Pertambangan seluas 39.296.08 Ha atau sekitar 56 % dari keselurahan luas Kabup aten Magetan

Predictive model of 2-cyclohexylthiophene for corrosion inhibition in mild steel using computational method

Corrosion inhibition activity of 2-cyclohexylthiophene (2CHT) for mild steel in acidic media was predicted using QSAR tool. The model used two descriptors namely; Moran autocorrelation of lag4 weighted by mass (MATS4M) which explained the linearity and branching of the compounds and largest eigen values n3 of burden matrix weighted by mass (SPMAX3-Bh(m)) describes the nature and size of the neighboring atom. The modeling results revealed the potential of the compounds as a good corrosion inhibitor with percentage inhibition efficiency (%IE) of 76.5%. Quantum chemical calculation using DFT with 6-311G++(d,p) basis was used to evaluate the performance of the predicted compound as corrosion inhibitor by quantum chemical parameters such as EHUMO, ELUMO, Energy gap (Egap), hardness (?), softness (S), dipole moment (µ), electronegativity (X), electron affinity (A), ionization energy (I) and total energy (TE). The results obtained from quantum chemical parameters were found to be consistent with predicted result

Students Impression About Using Mobile Phones in Classroom

Mobile phones are widely used by university students and there is a controversial topic whether students should be able to use them freely during lectures. A survey was distributed seeking student opinions on using mobile phones in classroom. We used two-phase sampling method to reduce the nonre-sponse bias. There were 392 valid responses. To test the effect of different factors on students' opinions a number of statistical techniques were utilized. The results showed Qatar University students marginally favored using mobile in classroom, but using mobile phone distracted some students who are less in favor of using phone during lectures. The proportion of students who believe that student should decide to use or not use mobile in the classes is 0.635. Apparently, students expected implementation of a policy that controls the use of mobile phones in class. Recommendations include a blanket policy for the University on the use of mobile phones during class, mobile phone breaks given by lecturers during class, utilizing mobile phone as an educational tool, with social media distractions blocked through the university system.Scopu