A Review on Energy Consumption Optimization Techniques in IoT Based Smart Building Environments

In recent years, due to the unnecessary wastage of electrical energy in residential buildings, the requirement of energy optimization and user comfort has gained vital importance. In the literature, various techniques have been proposed addressing the energy optimization problem. The goal of each technique was to maintain a balance between user comfort and energy requirements such that the user can achieve the desired comfort level with the minimum amount of energy consumption. Researchers have addressed the issue with the help of different optimization algorithms and variations in the parameters to reduce energy consumption. To the best of our knowledge, this problem is not solved yet due to its challenging nature. The gap in the literature is due to the advancements in the technology and drawbacks of the optimization algorithms and the introduction of different new optimization algorithms. Further, many newly proposed optimization algorithms which have produced better accuracy on the benchmark instances but have not been applied yet for the optimization of energy consumption in smart homes. In this paper, we have carried out a detailed literature review of the techniques used for the optimization of energy consumption and scheduling in smart homes. The detailed discussion has been carried out on different factors contributing towards thermal comfort, visual comfort, and air quality comfort. We have also reviewed the fog and edge computing techniques used in smart homes

Energy threshold sensitivity for frame loss

The energy of speech frames can be one of the ways to express least significant frames. The energy is a frame of speech is a time domain measure, speech frames having lowver energy are correlated with low perception as well. In this chapter the 100vest sensitivity energy frames is detailed and that can be utilised for STDM intelligent architecture

Speech quality for LPC envelope criterion

The design of STOM based upon LPC envelope distance is used in simulation. The simulation based upon this criterion, performance of the SIDM is provided in this chapter. The quality of speech is measured subjectivel

Transmission bandwidth efficiency enhancement techniques

All communication channels transmit infonnation fonn one user to another using channel bandwidth mostly measured in bits/second. With the advent of latest technological tools, the bandwidth efficiency of all the channels may be enhanced beyond their normal transmission capability; mean more bits can be transmitted through the same channel. Techniques such as low bit rate encoding, variable bit rates, compression of source data, digital speech interpolation, discontinuous transmission and lost frame reconstruction are some of those signal processing techniques that can be exploited to enhance bandwidth efficiencies of the channels. In this chapter bandwidth efficiency techniques are detaile

Linear predictive coding of speech

Linear Predictive Coding (LPC) is a mathematical (signal processing) technique used to remove the redundancy from speech signals. To remove the redundancy from speech signal, is done in 1\vo stages, first stage is to remove short term correlations form the signal and the second is to remove long term correlations. The short term and long term redundancies are modelled by digital filters very precisely. This chapter is dedicated for LPC ofspeec

Low bit rate speech coding

In recent years much work has be concentrated on encoding speech. Various coding methods are developed such as Low-Delay Codebook Excited Linear Prediction (LD-CELP), Codebook Excited Linear Prediction (CELP), Pulse Residual Excited Linear Prediction (PRELP) and others. These encoders operate at very low bit rates (4.8Kbps) as well as maintained speech quality. In this chapter some ofthese encoding algorithms are explaine

Digital multiplexing techniques

Multiplexing techniques are broadly classified as analogue and digital, digital being the latest. Time Division Multiplexing (TDM) and Statistical TOM are most commonly used digital multiplexing techniques. The TOM is a detenninistic method of multiplexing various sources in pre-determined fixed slots. Statistical TDM, (STDM) uses dynamic method of allocating time slots to only the active users. The dynamic nature of slot allocations enhances bandwidth utilization better than TDM however this property of STDM is always suitable for non-delay sensitive systems. For real-time and delay sensitive systems the TDM approach is the better optio

Discontinuous transmission and multiplexing

Discontinuous Transmission (DTX) is a concept used in some mobile standards, mostly in Groupe Special Mobile (GSM) systems. In DTX systems, Voice Activity Detection (VAD) and comfort noise are essential element. The usage of DTX in the systems allo\vs transmissions during activity periods and remains silent during non-activities. This chapter is dedicated for DTX and VAD, their usage in STDM design

Low bit rate speech multiplexer tools

In multiplexing many sources are combined in a common channel to maximise the bandwidth of the system. There can be many components of the STDM such as compressed speech sources at lower rates, voice activity detectors and lost frames reconstruction. This chapter briefly explains all three major components for the under lying multiplexer architectures

Quality assessments in multiplexing

Considering low bit rate sources the quality of speech suffers mainly by a factor, such as quantization noise. Multiplexing efficiency is therefore, based upon the encoding sources bit rates. Lower the coding rates, better the efficiency but on the expense of quality. The quality in multiplexing is assessed by two means, objectively and subjectively. In this chapter the quality assessment by both objective and subjective means is discussed for the STDM design consideration