Traditional transmission line ratings are limited by a set of fixed conservative weather assumptions that are also known as static thermal rating (STR). Owing to STR, new line corridors are continuously required to address increasing electricity demands while minimizing the curtailment of renewable energy sources (RES). However, the expansion of an electricity network is expansive, long, and limited due to the scarcity in land and space. To overcome this issue, researchers have proposed a dynamic thermal rating (DTR) system that can increase the capacity of existing transmission lines. Research has shown that actual line ratings are higher than STR most of the time. The potential of using the DTR system to increase the reliability of power systems is therefore significant. Almost every country has begun the process of increasing the integration of RES, and consequently, the DTR system has become increasingly important. Exploring and reviewing critical studies on the DTR system are thus beneficial for researchers who are interested in the developments of DTR technology. This review paper begins by comparing the two main DTR system standards. Then, monitoring technologies of the DTR system are reviewed. Notable research on the reliability impacts of the DTR system on electrical networks are surveyed. Interactions with wind power and other smart grid technologies are also examined, and the concept of power system reliability is briefly discussed.

The output power from a photovoltaic (PV) system varies due to its high dependency on the surrounding irradiance and temperature. To overcome this, a maximum power point (MPP) tracker is used alongside a DC-DC converter to track the varying power. The purpose of the DC-DC converter is to interface the PV system to the load on the grid or a standalone system by balancing the power between them. Selection of the appropriate DC-DC converter is essential because it plays an important role in the overall performance of the PV system. In this paper, various nonisolated conventional DC-DC converter topologies are reviewed, compared, and discussed. The review and discussion of each converter are based on the recent development of converters in terms of efficiency, steady state oscillation, number of components, voltage transfer, and tracking speed. The advantages and disadvantages of the recent topologies within this scope are also highlighted in this paper. A simulation work has been performed to validate the performance of all the reviewed converters using the perturb and observe MPP tracking algorithm under different sets of irradiance and temperature. Finally, this paper also provides a selection method to select the best converter in a stand-alone PV system.

Stuttering is a speech disorder in which the normal flow of speech is disrupted by occurrences of dysfluencies, such as repetitions, interjection and so on. There are a high proportion of repetitions and prolongations in stuttered speech, usually at the beginning of sentences. Consequently, acoustic analysis can be used to classify the stuttered events. This paper describes particular stuttering events to be located as repetitions and prolongations in stuttered speech with feature extraction algorithm. The well known Mel Frequency Cepstral Coefficient (MFCC) feature extraction is implemented to test its effectiveness in recognizing prolongations and repetitions in a stuttered speech. In this work, two classifiers such as Linear Discriminant Analysis based classifier (LDA) and k-nearest neighbors (k-NN) are employed and k-fold cross-validation was applied to measure classifiers performances. The result of this work shows that the MFCC and classifiers (LDA and k-NN) can be used for recognition of repetitions and prolongations in stuttered speech with the average accuracy of 90%.

An improved multilevel inverter (MLI) topology using a new basic unit structure with a reduced number of components is proposed in this study. Its single compact module is made up of two basic units connected to the left and right sides of a packed H‐bridge. The topology produces 9‐Level output when operated symmetrically and 17‐Level output when operated asymmetrically. Identical magnitude of DC sources is used for the symmetrical operation, while non‐identical magnitudes in a trinary sequence are used for the asymmetrical operation. The low‐frequency modulation scheme is applied for the switching control where the switching angles are pre‐calculated. The mathematical formulations for the switching are also considered to reduce the total harmonic distortion (THD) at the output. The proposed topology is also found to be superior in terms of the required number of switches per output level and total blocking voltage compared to conventional and recently reported MLIs. With these merits, real‐time installation of the proposed topology will potentially require lesser space and become cheaper. The feasibility of the proposed topology is validated for its 9‐Level and 17‐Level operations through experimental verification on output characteristics, THD, blocking voltage, power‐sharing and efficiency.