Improvements have been made to a commercial Linnik microscope in order to perform measurements in water for studying structures of transparent and non-transparent samples. One of the main goals of the present work is to study pollutants in colloidal layers immersed in liquid. The second reason to work in liquid is to increase the lateral resolution. The challenges to overcome include achieving stability in the complex Linnik design as well as the difficulty of balancing the optical distance of the two arms of the interferometer to obtain the interference fringes. The main problem is the path length compensation in the mirror arm which needs a complex mechanical design to allow a high enough number of degrees of freedom for to correct alignment of the optical elements. In our system, the reference mirror arm is mounted horizontally, making liquid immersion tricky. In this work, we have investigated alternative solutions based on non-liquid elastic polymers placed between the end of the objective and the reference mirror using sodium polyacrylate (SPA) beads and PDMS (polydimethylsiloxane) slabs, with a refractive index very close to that of water. The results of the performance tests of the modified system are presented and demonstrated. The new design provides a workable system that is ready for the future study of colloidal and other samples directly in water.

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The needs of flood disaster management encourage various efforts from all scientific disciplines of science, technology, and society. This article discusses the efforts to prevent flooding due to the habit of disposing of their waste into rivers through an innovative waste management system using the approach and application of Internet-based technology (IoT). Previous research has produced a prototype of the waste level monitoring system. In this research, the prototype was developed into a practical technology, called SiKaSiT (IoT Based Trash Capacity Monitoring System). This technology aims to assist janitor in monitoring, controlling and obtaining information about trash capacity and disposal time easily through an application on the smartphone in real-time and online. The system was made using a level detection sensor integrated with NodeMCU and Wi-Fi, MQTTbroker-protocol and Android-based application. Furthermore, the system was implemented in Bojongsoang adjacent to the Citarum river, where the water often overflowed due to the high rainfall and volume of trash around it. The results of system testing in the field shown good performance with value ranges of reliability is (99,785 - 99,944)% and availability is (99,786 - 99,945)%. SiKaSiT has several advantages over other similar systems. First, there is an application on the user's smartphone to monitor the capacity of trash and notification for full-bin. Second, the ability to operate on a small-bandwidth internet network because the throughput time is only around 0.59 kbps, thereby saving internet bandwidth consumption. This system has also helped overcome the problem of community trash management in Kampung Cijagra, where 60% of them gave feedback "agree" and the rest "strongly agree".Keywords: waste, IoT, monitoring, flooding, riverABSTRAKKebutuhan penanggulangan bencana banjir mendorong berbagai upaya dari semua disiplin ilmu baik dari bidang sains, teknologi dan sosial. Dalam artikel ini, penulis membahas upaya pencegahan banjir akibat kebiasaan membuang sampah ke sungai melalui inovasi sistem manajemen sampah menggunakan pendekatan dan penerapan teknologi berbasis Internet of Things (IoT). Pada riset sebelumnya telah dihasilkan sebuah prototype sistem monitoring level sampah. Kemudian pada riset ini prototype tersebut dikembangkan menjadi suatu teknologi tepat guna, dinamakan dengan SiKaSiT (Sistem Pemantauan Kapasitas Sampah Berbasis IoT). Teknologi ini bertujuan untuk membantu petugas kebersihan dalam memantau, mengontrol dan memperoleh informasi tentang kapasitas sampah dan waktu pembuangan sampah dengan mudah melalui aplikasi di smartphone secara real time dan online. Sistem dibuat dengan menggunakan sensor deteksi ketinggian sampah yang diintegrasikan dengan NodeMCU dan Wi-Fi, protokol MQTT broker dan aplikasi berbasis android pada smartphone. Selanjutnya sistem diimplementasikan di daerah Bojongsoang yang berdekatan dengan sungai Citarum yang airnya sering meluap akibat tingginya curah hujan dan volume sampah di sekitarnya. Hasil pengujian sistem di lapangan menunjukkan kinerja yang baik dengan kisaran nilai reliability adalah (99,785 – 99,944) % dan availability adalah (99,786 – 99,945) %. SiKaSiT memiliki beberapa kelebihan dibanding sistem serupa lainnya. Pertama, adanya aplikasi di smartphone pengguna untuk memonitor kapasitas sampah dan notifikasi saat tempat sampah penuh. Kedua, sistem mampu beroperasi pada jaringan internet bandwith kecil karena waktu throughput-nya hanya sekitar 0,59 kbps sehingga menghemat konsumsi bandwith internet. Sistem ini juga telah membantu menanggulangi permasalahan pengelolaan sampah masyarakat Kampung Cijagra, dimana 60% masyarakat memberi feedback “setuju” dan sisanya “sangat setuju”.Kata kunci: Sampah, IoT, Monitoring, Banjir, Sungai

Kejadian luka tekan pada lansia di rumah merupakan masalah global yang terus diupayakan untuk diminimalisir risikonya. Luka tekan pada lansia di rumah telah diketahui memiliki karakteristik yang berbeda dengan luka tekan yang terjadi pada pasien lansia di rumah sakit atau rumah perawatan. Tujuan penelitian ini adalah untuk mengidentifikasi faktor risiko dominan berdasarkan pengukuran skala Braden serta kekuatan hubungan diantara faktor risiko tersebut yang mempengaruhi keparahan luka tekan pada lansia di masyarakat. Penelitian ini merupakan penelitian potong lintang (cross sectional) terhadap 35 orang lansia yang memenuhi kriteria inklusi dan eksklusi dari 325 orang lansia di masyarakat yang ditemui dan dipilih secara acak. Data dianalisis dengan rumus korelasi Pearson menggunakan software Matlab. Hasil penelitian menunjukkan faktor dominan yang mempengaruhi tingkat keparahan luka tekan pada lansia di masyarakat adalah faktor aktivitas (r=0.9437), mobilisasi (r=0.9200) dan gesekan (r=0.8603). Sebaliknya, faktor kelembaban dan nutrisi memiliki hubungan paling rendah. Interaksi faktor gesekan dengan faktor aktivitas dan mobilitas sangat kuat mempengaruhi kejadian luka tekan pada lansia di masyarakat dengan nilai r berturut turut adalah 0.8405 dan 0.8200. Hasil penelitian merekomendasikan adanya upaya untuk meminimalkan faktor gesekan pada bagian tubuh lansia di masyarakat.

Crackles is one of the types of adventitious lung sound heard in patients with interstitial pulmonary fibrosis or cystic fibrosis. Pulmonary crackles of discontinuous short duration appear on inspiration, expiration, or both. To differentiate these pulmonary crackles, the medical staff usually uses a manual method, called auscultation. Various methods were developed to recognize pulmonary crackles and distinguish them from normal pulmonary sounds to be applied in digital signal processing technology. This paper demonstrates a feature extraction method to classify pulmonary crackle and normal lung sounds using Support Vector Machine (SVM) method using several kernels by performing spectrograms of the pulmonary sound to generate the frequency profile. Spectrograms with various resolutions and 3-fold cross-validation were used to divide the training data and the test data in the testing process. The resulting accuracy ranges from 81.4% - 100%. More accuracy values of 100% are generated by a feature extraction in several SVM kernels using 256 points FFT with three variations of windowing parameters compared to 512 points, where the best accuracy of 100% was produced by STFT-SVM method. This method has a potential to be used in the classification of other biomedical signals. The advantages of that are that the number of features produced is the same as the N-point FFT used for any signal length, the flexibility in the STFT parameters changes, such as the type of window and the window's length. In this study, only the Keiser window was tested with specific parameters. Exploration with different window types with various parameters is fascinating to do in further research.

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There are two types of tools for measuring the foot posture, uniplanar (anthropometric and radiographic types) and multiplanar tools (such as Foot Posture Index-6 and -8). The process of the foot posture measurement with both tools performed by a doctor were commonly carried out by using manual equipment such as ruler, arc, goniometer, marker and applying the observation skill by eyes. It needs time to measure for each foot. For research needs, a large number of samples has to be provided by a doctor to analyze data statistically which consumes much more time and exhaustion from work load in the measurement process. Hence, the aim of this study is to significantly decrease the measurement time and minimizing human error by developing a software of anthropometric measurements of foot posture based on digital image processing (DIP). The anthropometric tests used in this study consist of Rear Foot Angle (RFA), Medial Length Arc Angle (MLAA) and Arch Height Index (AHI). Instead of using equipment with a series of measurement to determine the foot posture, the DIP system only need two pictures of foot as the input of the system. The methods involved in the image processing are performed by a series of digital image processing, started from pre-image processing, noise filter, Sobel edge detection, feature extraction, calculation and classification. The result of the image processing is able to determine the foot posture types for all tests based on the values of angle and length of the foot variables. The error measurements of length and angle are 6.22 % and (0.26-1.74) %, respectively. This study has demonstrated the development algorithm in MATLAB to measure the foot posture, which is named Anthro-Posture v1.0 software. This software offers an efficient alternative way in measuring and classifying the foot posture in a shorter time and minimizing the human error in measurement process. In the future, this study can be improved to be used by doctors in obtaining large amounts of data for research needed.

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