Internet of things (IoT) is not a single word, but it has gathered billions of devices in the same lane. The Internet of things has given the lives of things. Machines have a sense now like a human. It works remotely as the program has been settled inside the chip. The system has become so smart and reliable. The Internet of things has brought out changes in most of the sectors of humankind. Meanwhile, agriculture is the main strength of a country. The more the production of agricultural products increased, the world will be more completeness from food shortage. The production of agriculture can be increased when the IoT system can be entirely implemented in the agricultural sector. Most of the approaches for IoT based agriculture have been reviewed in this paper. Related to IoT based agriculture, most of the architecture and methodology have been interpreted and have been critically analyzed based on previous related work of the researchers. This paper will be able to provide a complete idea with the architecture and methodology in the field of IoT based agriculture. Moreover, the challenges for agricultural IoT are discussed with the methods provided by the researchers.

<span>Nowadays, implementation of real-time embedded system or safety-critical in a real-time system is significant within emerging technologies because the system involves many aspects such as safety and task execution without missing deadlines. The main cause of implementation is to avoid catastrophic loss. Besides that, effectuation of the mixed-criticality system in embedded system making system more complex for task execution. For an embedded system, the main component involves real-time scheduling. The implementation of DPM method in real-time scheduling is well known, but in the mixed-criticality system, DPM method is still lacking. In order to cater this problem, Dynamic Power management (DPM) method is deployed onto the microcontroller of the mixed-criticality system to save energy when executing tasks in order to have better performance in the system. The usage of the DPM method in mixed-criticality of microcontroller resulting decrease of 0.82% in LED output voltage value meanwhile, for the LCD output, the voltage value decreased by 1.37% in the home alarm system. Thus, the energy-saving in the microcontroller of the mixed-criticality system using the DPM method is defined.</span>

Wireless Fidelity (Wi-Fi) fingerprinting is a remarkable approach developed by modern science to detect the user’s location efficiently. Today, the Global Positioning System (GPS) is used to keep track of our current location for outdoor positioning. In GPS technology, satellite signals cannot reach indoor environments as they are shielded from obstructions so that indoor environments with a lack of Line of Sight (LoS) do not provide enough satellite signal accuracy. Since indoor environments are very difficult to track, thus, a wide variety of techniques for dealing with them have been suggested. The best way to offer an indoor positioning service with the current technology is Wi-Fi since most commercial infrastructure is well equipped with Wi-Fi routers. The use of Wi-Fi fingerprinting techniques is becoming more common in the field of indoor positioning systems (IPS). For the purpose of indoor location localization, each method for obtaining a Wi-Fi fingerprint has been analyzed and discussed in this work. In this study, the majority of the algorithms that are associated with Wi-Fi fingerprinting have been interpreted, and the earlier works of other researchershave been critically evaluated, in order to get a more in-depth understanding of how the Wi-Fi fingerprinting process works.

Universality-Every person possesses the same characteristic that a normal human being does. 2. Uniqueness-Every person has a unique characteristic. That is, no two individuals possess the same characteristic. 3. Permanence-The characteristic is time invariant. It does not change in time. 4. Collectability-The characteristic can be quantitatively measured and is easily available to collect.