Prediction of Temperature Difference across Thermoacoustic Stack through Artificial Neural Network Technique

This study involved the application of artificial neural network (ANN) as a new approach for thermoacoustic refrigerators to predict the temperature difference across the stack under some operating conditions. One ANN model for a standing wave thermoacoustic refrigerator, had been developed based on the experimental data from other literature. Temperature difference across the stack was chosen as a response to the input parameters, mean pressure and frequency in the proposed ANN model. A multi-layer feed-forward neural network with a back propagation algorithm had been proposed for predicting the temperature difference across the stack of the thermoacoustic refrigerator. This proposed ANN model has three layers with configuration 2-12-1, namely, input layer with two neurons representing the two operating parameters, one hidden layer with an optimal 12 hidden neurons, and output layer with one neuron representing the temperature difference across the stack, as response. The high ability of ANN for data prediction was proven in this study through achieving an average prediction error of 0.2% and a regression coefficient (R) of 0.99979 during testing phase. This research work provides a new approach based on ANN technique to solve complex thermoacoustic problems with linear or nonlinear nature through either modeling, optimization or system identification

Wake Field Interaction in 3D Tidal Turbine Arrays: Numerical Analysis for the Pentland Firth

This study presents a methodology for applying the three-dimensional actuator disk-RANS technique in modeling tidal energy converters within a regional-scale simulation. Of particular interest are the robustness of the applied momentum source term and its effectiveness in modeling an array of full-sized tidal turbines under realistic hydrodynamic and operational conditions. The Inner Sound region, which is the site of commercial-scale deployment projects of the Pentland Firth in Scotland, is chosen as the study area. While the actuator disk approach had been used in past studies to parameterize the far-wake region of horizontal-axis tidal turbines, details of its three-dimensional implementation have not been thoroughly discussed. Criteria adopted in deciding the array location are presented in this study, along with the actuator disks’ detailed setup and constraints. The models are subjected to one operational characteristic that is similar to commercial devices in service to examine the accuracy of the imposed source term under complex flow conditions. The results demonstrate that the thickness of the disk imposed in the source term has a pronounced influence on the model outputs. In addition to accurately modeling flow propagation and wake interactions, the models are also able to replicate the observed asymmetrical tidal currents in the region. Because there is currently limited published material on the detailed application of the actuator disk approach in ocean-scale models, this study is hoped to fill the research gap and provide evidence, guidance, and examples of best practices for future studies

SIKAP HIDUP TOKOH UTAMA 铁木真 TIĔ MÙZHĒN DALAM FILM 《战神纪》 ZHÀNSHÉNJÌ: KAJIAN ANTROPOLOGI

Abstrak Penelitian ini bertujuan untuk menganalisis sikap hidup tokoh utama dalam film 战神纪 (zhànshénjì) atau Gengis Khan (2018) yang bernama 铁木真 Tiě Mùzhēn dalam berhubungan dengan orang tua, pasangan, keluarga, teman, musuh, dan orang lain. 铁木真 Tiě Mùzhēn merupakan salah satu tokoh bersejarah pada masa kejayaan Mongolia. Jenis penelitian ini adalah penelitian deskriptif kualitatif. Selain itu, penelitian ini menggunakan kajian antropologi yang berkaitan dengan sikap hidup masyarakat Mongolia yang dikenal memiliki kepribadian yang tulus, jujur, adil, berbudi luhur atau patuh adat, ramah, dan mandiri. Berdasarkan dari hasil analisis pada film tersebut ditemukan bahwa (1) 铁木真 Tiě Mùzhēn selalu bersikap budi luhur dan berkata jujur terhadap orang tua, (2) bersikap jujur dan tulus terhadap pasangan, (3) bersikap budi luhur, jujur, dan mandiri terhadap keluarga, (4) bersikap tulus terhadap teman, (5) bersikap adil terhadap musuh yang telah berbuat buruk kepadanya, (6) bersikap budi luhur, jujur, dan ramah terhadap orang lain. Kata Kunci: Antopologi, Film, Sikap Hidup, Tokoh Utama, Suku Mongol Abstract This study aims to analyze the way of life of the main character in the movie 战神纪 (zhànshénjì) or Gengis Khan (2018) named 铁木真 Tiě Mùzhēn in interaction with parents, wife, family, friends, enemies, and other people. 铁木真 Tiě Mùzhēn is one of the historical figures of the glory of Mongolia. This type of research is descriptive qualitative research. In addition, this study uses anthropological studies related to the way of life the Mongolian people who are known to have a sincere, honest, fair, virtuous or customary obedient, friendly, and independent personality. Based on the results of the analysis on the movie, it was found that (1) 铁木真 Tiě Mùzhēn always behaved virtuously and told the truth to his parents, (2) was honest and sincere towards his partner, (3) was virtuous, honest, and independent towards his family, (4) being sincere towards friends, (5) being fair to enemies who have done bad to him, (6) being virtuous, honest, and friendly to others. Keywords: Anthropology, Movie, Way of Life, Main Character, Mongolia

Theories of system of cities;

Economic theories of systems of cities explain why production and consumption activities are concentrated in a number of urban areas of different sizes and industrial composition rather than uniformly distributed in space. These theories have been successively influenced by four paradigms: i) conventional urban economics emphasizing the tension between economies due to the spatial concentration of activity and diseconomies arising from that concentration; ii) the theory of industrial organization as it relates to inter-industry linkages and to product differentiation; iii) the New Economic Geography which ignores land markets but emphasizes trade among cities, fixed agricultural hinterlands and the endogenous emergence of geography; iv) the theory of endogenous economic growth. Among the issues examined are specialization versus diversification of cities in systems of cities, how city systems contribute to increasing returns in national and the global economies, the factors that determine skill distribution and income disparity between cities, the impacts of income disparity on welfare, whether population growth should cause economic activity to become more or less concentrated in urban areas, and how resources should be allocated efficiently in a system of cities. Related to the last issue we consider models where cities are organized by local planners or developers as well as cities that self organize by atomistic actions. A conclusion of the theoretical study of city systems is that markets fail in efficiently allocating resources across cities when certain intercity interactions are present and that a role for central planning may be necessary

On Street Parking Effect To Performance Of The Imam Bonjol Street In Palu City

Traffic jam caused by a lots of vehicles which parked on the road has always been a problem on urban roads. The lack of parking facilities out of the road and a lot of generation due to public facilities such as bank, restaurants, pharmacies, shops, and health center, will have an impact on traffic jam on the Imam Bonjol road section. This research aim for determine the magnitude effect of parking on street to the road performance of the Imam Bonjol street. The data needed includes, highway geometric, collecting data obtained from the results of the surveys is data on traffic volume, side barriers, parking on the road data and speed data. The parking survey methods using plat number methods and the data was analysed using the MKJI 1997 calculation method. The results of this research indicate that parking on the road is affected the performance of the imam bonjol street. the amount of traffic volume on saturday at 20.00 - 21.00 WITA is 3034 vehicles/hour. Side barriers values obtained is 560.7 friction/hour with high conditions typical is commercial areas, high activities on the road side, so the value of capacity dropped from 4576 smp/hour before parking, to 2533 smp/hour after parking on the road. The value average speed of light vehicle on Saturdays for the west to east is 24,42 km/hour, while the east to west is 23,94 km/hour. In 2018 the DS value is 0.65 with the level of service C. Whereas in 2023 the performance increased to DS = 1,23 with the level of service F

A multiscale cavity method for sublinear-rank symmetric matrix factorization

We consider a statistical model for symmetric matrix factorization with additive Gaussian noise in the high-dimensional regime where the rank $M$ of the signal matrix to infer scales with its size $N$ as $M = o(N^{1/10})$. Allowing for a $N$-dependent rank offers new challenges and requires new methods. Working in the Bayesian-optimal setting, we show that whenever the signal has i.i.d. entries the limiting mutual information between signal and data is given by a variational formula involving a rank-one replica symmetric potential. In other words, from the information-theoretic perspective, the case of a (slowly) growing rank is the same as when $M = 1$ (namely, the standard spiked Wigner model). The proof is primarily based on a novel multiscale cavity method allowing for growing rank along with some information-theoretic identities on worst noise for the Gaussian vector channel. We believe that the cavity method developed here will play a role in the analysis of a broader class of inference and spin models where the degrees of freedom are large arrays instead of vectors

Penerapan Model Pembelajaran Penemuan Terbimbing Pada Materi Teorema Pythagoras Siswa Kelas VIII MTsS Darussyariah Banda Aceh

Pembelajaran yang sering terjadi disekolah selama ini kurang memberikan kesempatan bagi siswa untuk menemukan pemahamannya secara mandiri. Hal ini berakibatsiswa merasa jenuh dan bosan dengan pembelajaran karena pembelajarannya tidak bervariasi sehingga berpengaruh negatif terhadap hasil belajar mereka.Diantara materi matematika yang sulit dipelajari adalah pokok bahasan Teorema Pythagoras. Karena pokok bahasan ini sering digunakan dalam topik geometri dan juga trigonometri.Salah satu model pembelajaran yang melibatkan siswa aktif adalah model pembelajaran penemuan terbimbing. Modelini selain dapat mengembangkan kemampuan kognitif siswa, juga dapat mengaktifkan dalam menemukan suatu konsep-konsep baru secara mandiri sementara guru hanya sebagai faliditasi dalam pembelajaran. Penelitian ini bertujuan untuk mengetahui apakah dengan penerapan model pembelajaran penemuan terbimbing pada materi teorema pythagoras dapat meningkatkan hasil belajar siswa kelas VIII MTsS Darussyariah Banda Aceh. Populasi dalam penelitian ini adalah seluruh siswa MTsSDarussyariah yang berjumlah 142 siswa, sementara sampel diambil hanya siswa kelas VIII-1dan siswa kelas VIII-2yang masing-masing berjumlah27 siswa dan 25 siswa. Pengumpulan data dilakukan melalui tes tulis yang terdiri dari pretest dan postest terhadap kelas eksperimen dan kelas kontrol. Datanilaipostest dianalisis dengan menggunakan uji-t, dari hasil pengolahan data tersebut diperoleh t_hitung>t_tabelyaitu 2,83> 1,68. Hasil analisis data pada taraf signifikan α = 0,5 menunjukkan bahwa hasil belajar siswa pada materi teorema pythagoras yang diajarkan dengan penerapan model pembelajaran penemuan terbimbing lebih baik daripada hasil belajar siswa yang diajarkan tanpa penerapan model pemebelajaran penemuan terbimbing. Dalam penelitian ini, peneliti juga mengamatikhusus pada kemampuan guru dalam mengelola pembelajaran, dan aktivitas siswa selama pembelajaran penemuan terbimbing.Kedua hasil pengamatan tersebut dianalis dengan statistik deskriptif sehinga meunjukkan hasil dari pengamatan tersebut dapat dikatagorikan dalam kelompok aktif dan baik. Sementara siswa memberikan respon sangat positif dalam penerapan model penemuan terbimbing ini