IoT merupakan salah satu kemajuan yang signifikan dalam bidang informasi dan teknologi dan terus dapat dikembangkan untuk kemudahan aktivitas manusia. Pada penelitian ini, Sistem pintar IoT berbasis arduino dan android untuk pengukuran keasaman dan nutrisi air pada hidroponik. Arduino digunakan sebagai prosesor data yang masuk dari sensor untuk ditampilkan pada layar dan direspon memlaui relay untuk menghidupkan pompa jika nilai TDS dibawah nilai yang ditentukan. Data dari arduino dikirim ke cloud firebase sehingga bisa diakses melalui perangkat android.  Perangkat lunak prosesor Arduino menggunkan bahasa C yang diedit pada IDE arduino. Android didesain menggunakan XML dan Kotlin untuk membantu proses control aplikasi yang dibuat menggunakan aplikasi android studio. Alat ukur arduino dikalibrasi dengan menggunakan data tegangan dan data PH serta data TDS yang seharusnya pada cairan kalibrasi. Kemudian didapatkan model linier untuk PH dan model polynomial pangkat tiga untuk TDS. Model tersebut diimplementasikan pada arduino dan didapatkan nilai pengukuran mendekati nilai kalibrasi dengan kesalahan 5.86% untuk PH dan 11.1% untuk TDS. Sistem IoT diamati dengan mencoba tampilan data serta otomasi dan control manual melalui android. Hasil tampilan, otomasi dan kontrol  manual bekerja secara efektif sesuai fungsi sebagai IoT.

Agriculture is important sector to fill the basic need of human: food. It will increase as the increasing of population. In this researh, IoT that was powered by solar power was successfully implemented to hydroponic system. The IoT controlled the parameter and solar panel power in the hydroponic system effectively where the solar panel generated power up to 2.5 kW during the day and it was used for powering greenhouse that need about 477 W power. Research was conducted by comparing productivity of conventional farming to hydroponic smart farming. The physical properties of plants from species of Ipomea aquatica, Brassica chinensi, Lactuca sativa, and Brassica rapa that were cultivated in smart farming and conventional farming were measured and analyzed. It was revealed that the height of Ipomoea aquatica was 52.63 cm in smart farming, whereas the height was 42.66 cm in conventional farming. The average height and weight of the plants and the number of leaves lead to the fact that smart farming results in higher productivity than other method because of optimum nutrition in smart farming.

The digital transformation has been a significant discussion since scientists predicted the birth of the digital era. The transformation affects many things, especially in the leadership concept. This article aims at investigating the development of academic literature on leadership in the digital era. We use bibliometric analysis and literature review to give further suggestions on which topics on leadership for a digital startup shall go to the fore. This study has mapped out the academic literature on the keyword "digital leadership" from the early year of the rise of the digital era in 2000, up until the end of 2018. This study shows that the topics related to digital leadership are digital transformation, internet, system, and organization. Between these four topics, the closest relation found in the topics of organization. Therefore to have a better understanding of leadership for the digital startup, further research should target the area of the organization