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Machine Learning-based Indoor Positioning Systems Using Multi-Channel Information
Get PDFThe received signal strength indicator (RSSI) is a metric of the power measured by a sensor in a receiver. Many indoor positioning technologies use RSSI to locate objects in indoor environments. Their positioning accuracy is significantly affected by reflection and absorption from walls, and by non-stationary objects such as doors and people. Therefore, it is necessary to increase transceivers in the environment to reduce positioning errors. This paper proposes an indoor positioning technology that uses the machine learning algorithm of channel state information (CSI) combined with fingerprinting. The experimental results showed that the proposed method outperformed traditional RSSI-based localization systems in terms of average positioning accuracy up to 6.13% and 54.79% for random forest (RF) and back propagation neural networks (BPNN), respectively
The Material Science Behind Repetitive Hammering, Solution Annealing, and Tempering on Hadfield Steel
Get PDFThe Hadfield steel used in this study contained 11 to 14% Mn and 1.1 to 1.4% C. Hadfield steel that underwent heat treatment showed insignificant differences in microstructure and hardness. On the other hand, Hadfield steel that was subjected to heat treatment combined with repetitive hammering exhibited changes in microstructure, as indicated by the presence of more and denser slip lines in accordance with an increased amount of deformation. The hardness value of the Hadfield steel also significantly increased. The slip lines discovered in the Hadfield steel that underwent solution annealing and tempering followed by repetitive hammering increased in number and appeared more compact than in the Hadfield steel without tempering. Additionally, the hardness value of the Hadfield steel with tempering was higher than that of the Hadfield steel without tempering. The strain values and thickness reduction results showed that the Hadfield steel subjected to tempering had higher strain and thickness reduction than the Hadfield steel without tempering. Higher strain and thickness reduction leads to higher hardness
Implementation of the Lora System for Temperature and Humidity Monitoring in POLBAN Classrooms
Get PDFThe need for temperature and humidity monitoring in classrooms, is very important for the purpose of comfortable teaching and learning processes, especially after the Covid-19 pandemic conditions. At Politeknik Negeri Bandung (POLBAN), there are more than a hundred classrooms. The rooms are spread over several buildings; therefore, the process of monitoring temperature and humidity will be difficult if it is done using a cable (wireline). In this study, a temperature and humidity monitoring system for classrooms at POLBAN will be made using LoRa wireless architecture. In several classrooms, temperature and humidity sensors will be installed combined with a LoRa sending system. There are conditioned room and unconditioned room. On the monitoring center, a LoRa receiver system is also installed. Data from each classroom, will wirelessly be sent to the monitoring center, for further processing. In the implementation stage, one gateway, 4 endnotes with DHT11 sensor are used. Testing process is carried out by verifying and monitoring performance in 4 classrooms and in open spaces. Results of verifying show a difference of 2℃ and 1% of the RH value with a reference measuring instrument. There is no difference in temperature and RH values at the endnode and gateway
Integrasi Sistem Kendali Lengan Robot pada Preparasi Mikrokapsul Brachytherapy
Get PDFHDR brachytherapy uses Ir-192 wrapped in microcapsules (seeds). Ir-192 requires high precision during the preparation process to produce good-quality seeds. The technological innovation of four DoF robot arms using LabVIEW and Arduino MEGA is equipped with an endoscope camera monitoring system to maximize preparation and minimize radiation exposure. The endoscope camera helps identify and observe seeds picked up by the vacuum gripper. The system starts by taking the seeds on the conveyor and placing them at the chuck. The robotic arm's test for accuracy and precision employs quantitative analysis. The linear motion angle test results in precision of 99.3% and accuracy of 100%; the base had 98.4% precision and 98.4% accuracy; Link 1 had 96.2% precision and 97.2% accuracy; and Link 2 had 72.4% precision and 71.5% accuracy. The average error of the inverse kinematics test was obtained: linear motion 0%, base 8.1%, Link 1 8.2%, and Link 2 9.8%. The average error of forward kinematics testing for positions a and z 0%, position x 25.1%, and position y 18.9%. The average success result for the seed collection test was 87%, the monitoring test result was 80%, and the seed placement test was 86%. The overall system test results yielded 80% for monitoring, picking, and placing seeds, with an average system accumulation time of 83.6 seconds.Brachytherapy HDR menggunakan Ir-192 yang dibungkus mikrokapsul (seed). Penggunaan Ir-192 membutuhkan tingkat presisi yang tinggi selama proses preparasi untuk menghasilkan seed berkualitas baik. Inovasi teknologi lengan robot empat DoF berbasis LabVIEW dan Arduino MEGA, dilengkapi sistem monitoring kamera endoskopi agar memaksimalkan preparasi sehingga meminimalisir paparan radiasi. Kamera endoskopi membantu mengidentifikasi dan mengamati seed yang diambil oleh vacuum gripper. Sistem dimulai dengan mengambil seed di conveyor lalu diletakkan pada chuck. Hasil akurasi dan presisi lengan robot, diuji menggunakan analisis kuantitatif. Hasil pengujian sudut linear motion memiliki presisi 99,3% dan akurasi 100%; base memiliki presisi 98,4% dan akurasi 98,4%; Link 1 memiliki presisi 96,2% dan akurasi 97,2%; dan Link 2 memiliki presisi 72,4% dan akurasi 71,5%. Rerata error pengujian inverse kinematics diperoleh linear motion 0%, base 8,1%, Link 1 8,2%, dan Link 2 9,8%. Rerata error pengujian forward kinematics diperoleh posisi dan 0%, posisi 25,1%, dan posisi 18,9%. Hasil rerata keberhasilan pengujian pengambilan seed 87%, pengujian monitoring 80%, dan pengujian peletakan seed 86%. Hasil pengujian keseluruhan sistem menghasilkan 80% untuk monitoring, pengambilan, dan peletakkan seed dengan waktu akumulasi rerata sistem sebesar 83,6 detik
Job Stress and Employees' Satisfaction in the Hospitality and Tourism Sector of North East India
Get PDFIn the modern times, the demand for hotel and tourism services is increasing rapidly. As a result, hospitality employees face enormous professional pressure at work. This work pressure causes them stress at work. Since job satisfaction is a prerequisite for providing the highest quality services, it largely depends on the level of stress in the workplace. In this study, determinants of job stress have been identified first and then an attempt has been made to study the impact of job stress on employees’ satisfaction. The study has been conducted with the help of primary data collected from the sample respondents from the study region. The study applies factor analysis and multiple regression analysis. The study confirmed that Eustress has direct positive relations with the job satisfaction of employees. Since, the study reveals that Duration of Work (DW), Job Profile (JP), and Expectation of Management (EM) have positively influenced job satisfaction. HR Policy (HRP) and Work Pressure (WP) negatively affected job satisfaction and these aspects should be taken care of by the management
Urban Planning Approach and Production of Counter Architecture: A Case Study of New Market, Khulna
Get PDFInformal spatial practices in cities of the Global South are often regarded as activities taking place outside the realm of regulatory oversight. The prevailing urban governance and planning paradigms, which are largely derived from developed countries, struggle to adapt to the dynamic nature of these practices and the inherent conflicts they entail. Furthermore, the influence of disorderly political systems further complicates matters at the local level. In response to planned development, informal spatial practices persist as a critical yet overlooked/integral aspect of ever-evolving urban realities. This paper provides new insights into the current dynamics surrounding the creation of informal urban spaces in Global South cities and their interaction with the formal planning framework. Our study focused on the city of Khulna in Bangladesh, a compelling case study with a history of failed industrial planning dating back to the 1960s, when it was designed by a group of British consultants. Following its initial failure and the city’s subsequent decline in population, Khulna has witnessed an unforeseen surge in ‘counter spatial’ development driven by the imperative to meet socio-economic and cultural needs. This paper underscores the significance of such type of informal spatial production and introduces/highlights the concept of ‘counter architecture’ as a pivotal element of society that demands recognition and inclusion in the broader urban development framework. It suggests that the ‘counter architecture’ lens provides a foundation for challenging the rigidity of master planning and understanding the interconnectedness between formal and informal urban spaces. This perspective emphasizes the need to consider the lived experiences and tactical attributes of spatial formation, ultimately highlighting the resistance of ‘inhabitants’ and ‘users’ against the static codes of modern master planning in cities of Global South like Khulna
Déjà Vu: The Untenable Reality of the Pavement Dwellers of Dhaka - Evidence from Three Decades
Get PDFPavement dwellers migrate to the city in search of better opportunities. Their commitment to this way of life is based on an expectation of benefits in the destination area. This study examined five aspects of pavement dwellers’ reality: demographics, socioeconomics, migration outcomes, living conditions, and fulfillment of expectations. A mixed-method data collection exercise resulted in 64 pavement dwellers’ accounts of their current situation in Dhaka city, which were compared to similar studies from 1991 and 1993. The results show that their conditions have remained unchanged. Though half of the migration occurred for economic reasons, the real income level has remained the same as in 1991. Shelter and employment remain elusive, and moving to slums is financially infeasible. More than half of those interviewed lived on the pavement for access to a livelihood. Most declared that they could not access social safety nets. The persistence of pavement dwelling in the face of remarkable economic growth demands the refocusing of policies on urban poverty eradication
Combatting Malaysia's Dengue Outbreaks with Auto-Dissemination Mosquito Traps: A Hybrid Stochastic-Deterministic SIR Model
Get PDFClassical mosquito control methods (e.g. chemical fogging) struggle to sustain long-term reductions in mosquito populations to combat vector-borne diseases like dengue. The Mosquito Home System (MHS) is an auto-dissemination mosquito trap, that kills mosquito larvae before they hatch into adult mosquitoes. A novel hybrid stochastic-deterministic model is presented, that successfully predicts the effect of deploying MHSs within high-rise flats in Selangor, Malaysia. Stochastic SIR (Susceptible-Infected-Recovered) equations (flats) are paired with an existing deterministic SIR model (wider Kuala Lumpur population). Model predictions provide excellent agreement with data from a 44 week MHS trial within the flats. The stochastic model is validated as a powerful tool for predicting short- and long-term impacts of deploying this style of trap within similar environments. Significant, sustainable reductions in mosquito populations are predicted when the MHS is active: with a mean of 9 (95% Uncertainty Range (UR): 1; 30) during the 44 week trial period, compared to 35 (95% UR: 1; 234) dengue cases with no MHSs. Long-term predictions for endemic equilibrium show MHSs significantly narrow the mosquito population distribution and reduce dengue prevalence: from a mean of 5 (95% UR: 0; 52) (no MHS), to 1 (95% UR: 0; 8) dengue cases annually (with MHS)
DAMPAK PARIWISATA TERHADAP KEHIDUPAN MASYARAKAT LOKAL DI KAWASAN WISATA (Desa Ciburial Kabupaten Bandung)
Get PDFCiburial Village is one of the tourist villages in Bandung Regency, with several tourist attractions such as the Juanda Forest Park, the Keraton Cliff, Dutch Cave, Japanese Cave, and cafes scattered throughout the Ciburial Village area. The mushrooming of these cafes is due to the strategic location of Ciburial Village and high demand, this has resulted in the conversion of agricultural land into commercial buildings. The land function change has an impact on the lives of the people of Ciburial Village. This study aims to identify the factors that influence the impact of tourism and analyze the impact of tourism on socio-cultural and economic aspects of the life of the people of Ciburial Village. This research is descriptive with a qualitative approach. Data collection is done by means of observation, interviews, and secondary data from the internet or related agencies. The analysis in this study uses data reduction, data presentation, and conclusions.Desa Ciburial adalah desa wisata di Kabupaten Bandung, dengan beberapa daya tarik wisata seperti Taman Hutan Raya Juanda, Tebing Keraton, Goa Belanda, Goa Jepang, dan kafe-kafe yang tersebar di seluruh wilayah Desa Ciburial. Menjamurnya kafe-kafe tersebut disebabkan karena lokasi Desa Ciburial yang strategis dan demand yang tinggi, hal ini berakibat terhadap alih fungsi lahan pertanian menjadi bangunan komersil. Alih fungsi lahan tersebut memberikan dampak terhadap kehidupan masyarakat Desa Ciburial. Penelitian ini bertujuan untuk mengidentifikasi faktor-faktor yang mempengaruhi dampak pariwisata dan menganalisis dampak pariwisata yang ditimbulkan terhadap aspek sosial budaya dan ekonomi pada kehidupan masyarakat Desa Ciburial. Dengan pendekatan kualitatif, penelitian ini memiliki karakteristik deskriptif. Pengumpulan data dilakukan melalui observasi, wawancara, dan pemanfaatan data sekunder dari internet atau instansi terkait. Adapun analisis yang digunakan dalam penelitian ini mencakup reduksi data, penyajian data, dan pembuatan kesimpulan
Variability of N-SPT-Correlated Undrained Shear Strength of Alluvial Deposit in Doplang Region, Central Java, Indonesia
Get PDFThe need to better quantify the variability of soil shear strength and its relations with the factor of safety is increasing in Indonesia. However, this aspect has not yet been studied thoroughly. This paper presents an attempt to quantify the variability of undrained shear strength in relation with the factor of safety of an alluvial deposit in the Doplang region, Central Java, Indonesia. A relationship between the undrained shear strength, su, and N-SPT for the deposit was found as su = 3.4 N-SPT. The variability of the undrained shear strength was quantified utilizing the coefficient of variance, s/m (the sample standard deviation, s over the mean, m) of the N-SPT correlated undrained shear strength. The variability of the undrained shear strength was investigated for the soil near ground surface. The deposit had a value of s/m ranging from 0.15 to 0.25 near ground surface. The variation of s/m tended to follow normal and lognormal distributions. Relationships among the coefficient of variance, the probability of failure, and the factor of safety in terms of soil strength for normal and lognormal distributions were developed. For the value of s/m near ground surface, the relationship between the probability of failure and factor of safety was obtained