Kehadiran internet membuka banyak peluang baru. Dari begitu banyak peluang, ada yang positif seperti pemanfaatan internet untuk komunikasi, tetapi juga ada peluang yang disalahgunakan sehingga terjadilah kejahatan siber. Kejahatan siber kerap terjadi di dalam jaringan, tak terkecuali pada jaringan sensor. Jaringan sensor memiliki tingkat kerawanan yang tinggi terhadap berbagai macam serangan siber termasuk di antaranya adalah perubahan data yang dapat menyebabkan data menjadi korup. Pada penelitian ini, Blockchain digunakan untuk menjaga dan menjaga integritas data pada jaringan sensor dengan memanfaatkan algoritma SHA-256. Penelitian ini bertujuan untuk melihat bagaimana Blockchain diterapkan pada sensor jaringan dan bagaimana performa Blockchain pada sensor jaringan. Dengan parameter penguji berupa kesesuaian blok, waktu yang diperlukan untuk membuat blok, serta ukuran penyimpanan blok, didapatkan bahwa blok pada Blockchain tidak mengalami kecacatan, dengan rata-rata waktu eksekusi 1,69 detik dengan kompleksitas waktu yang linear dan rata-rata ukuran blok sebesar 176 bytes pada setiap blok setelah blok pertama.

Butterfly-pea (Clitoria ternatea) flowers are containing various active compounds such as flavonoids, myricetin, quercetin, flavonols, and anthocyanins which have potential as antioxidants. Dried butterfly-pea flower is often used as an ingredient of herbal tea drinks. The drying procedure for the butterfly-pea flower is important to maintain the shelf-life. However, during the drying process, anthocyanins are easily be degraded before reaching the balance of water content. Therefore, a study focus on moisture sorption isotherm of fresh butterfly-pea flowers is needed. This present study aims to determine the balance of water content and isosteric heat of butterfly-pea flowers using a static gravimetric method. Water activities were conditioned using chemical solutions of KOH, MgCl2, K2CO3, NaCl, KCl, and BaCl2 with a water activity range of 0.06-0.90. The hysteresis curve was determined using desorption and adsorption samples with various temperature variations of 30, 40, and 50°C. The isothermal behavior of butterfly-pea flowers was determined based on GAB, BET, Halsey, Oswin, and Peleg models. As a result, the Peleg model was found to be the most suitable model to represent the moisture sorption isotherm of butterfly-pea flowers and based on Brunauer classification including the Type II-sigmoid curve in which has been statistically analyzed using determination coefficient (R 2), mean relative modulus (P), and root mean square error (RMSE). The hysteresis curve indicated that the balance of water content of the desorption sample is higher than the adsorption sample on the same water activity level. The net isosteric heat in the desorption and adsorption samples were 48.529 exp (−xe/0.0734) and 53.591 exp (−xe/−0 0797), respectively.

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In this paper, an IOT based climate monitoring system for rural area is proposed. The selected location for IOT sensor placement is Sumberbrantas village which is vulnerable for flood, landslide and strong wind disasters. For these reasons wind behaviors, rainfall and temperature sensors are installed in IOT stations. Based on information from local residents, strong winds always blow every year. The wind flowed for several days causing residents to be unable to move outside their homes. This wind is flowing so fast that it can damage the roof of the house. However, currently there is still no device that accurately measures changes in air pressure or wind speed in the area. To collect data, as well as to anticipate problems caused by these strong winds, an IOT-based monitoring system was built to observe the weather that occurred in the area. Experiments show that the proposed monitoring system is able to send monitoring data every 5 minutes. The monitoring data consist of temperature, humidity, wind direction, wind speed, barometric pressure and rainfall.

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