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Article

29 January 2024

A Novel High Step-up DC-DC Converter Using State Space Modelling Technique for Battery Storage Applications

This paper focuses a novel non-isolated coupled inductor based DC-DC converter with excessive VG (voltage gain) is analyzed with a state-space modeling technique. It builds up of using three diodes, three capacitors, an inductor and CI (coupled inductor). The main switch S is turn on due to body diode and voltage stress is reduced at the switch S by using diode D1 and Capacitor C1. This paper focuses on design modelling, mathematical calculations and operation principle of DC-DC converter is discussed with state-space modelling technique. The performance has been presented for two different voltages for EV applications i.e., 12 V, 48 V as input voltages with an high step-up outputs of 66 V and 831.7 V respectively. The converter stability is studied and determined the bode plot along with simulation performance results which are carried out using MATLAB R2022B.

Keywords: DC-DC Converter; Energy Storage System; High Step-Up; State-Space Modelling

Article

29 January 2024

Determining the Identity of Corpses Using Fingerprints: Results from Practice and Analysis of Process Used in the Republic of Serbia

In today’s world, when there is a constant fight against organized crime and terrorism, when we have cases of mass accidents (plane crashes, train crashes, buses, etc.), the constant need for precise and quick identification of persons is evident in these cases. When we have situations with a large number of dead in various conditions, as well as complete or only parts of the body being on the spot, there is a need to use scientific and forensic methods in order to find out the reliable identity of these people. Furthermore, there is a need, in some cases, to identify persons who committed suicide, were killed, or died a natural death (accidental death) and who do not have documents according to which their identity can be determined. The aim of this paper will, however, be to identify a group of persons who need to be identified, known as unidentified corpses. Method. Describe and discuss the way of determining identity based on dactyloscopic data, which provides accurate and unambiguous identification, using fingerprints. Results. The identity was determined in 1271 cases of unidentified corpses by dactyloscopic comparison of fingerprints with a database containing fingerprints of about 8,000,000 indisputably identified persons. It was confirmed in 1139 cases. Conclusion. The high degree of identification in our research, as much as 89.6%, makes this method rightly represented as a standard method for confirming a person’s identity.

Keywords: Unidentified corpse; Identity; Dactyloscopy; Fingerprint; Friction ridge; Identification; Verification

Article

29 January 2024

The “Global Change Data Base” GCDB Facilitates a Transition to Clean Energy and Sustainability

This article presents the opportunities for constructing a global data base picturing underlying trends that drive global climate change. Energy-related CO2 emissions currently represent the key impact on climate change and thus become here the object of deep, long-term and historiographic analysis. In order to embrace all involved domains of technology, energy economy, fuel shares, economic efficacity, economic structure and population, a “Global Change Data Base” (GCDB) is suggested, based on earlier worldwide accepted data repositories. Such a GCDB works through regressions and statistical analysis of time series of data (on extensive magnitudes such as energy demand, population or Gross Domestic Product, GDP) as well as generation of derived data such as quotients of the former, yielding intensive magnitudes that describe systems and their structural properties. Moreover, the GCDB sets out to compute the first and second time derivatives of said magnitudes (and their percentual shares) which indicate new long-term developments already at very early phases. The invitation to participate in this foresight endeavour is extended to all readers. First preliminary GCDB results quantitatively portray the evolutionary structural global dynamics of economic growth, sectoral economic shifts, the shifts within energy carriers in various economic sectors, the ongoing improvements of energy intensity and energy efficiency in many economic sectors, and the structural changes within agricultural production and consumption systems.

Keywords: Forward looking; Future research; Techno-socio-economic evolution; Global development; Global scenarios; National scenarios; Foresight; Forecast; Technology assessment; Energy; Economy; Agriculture; GCDB; Global Change Data Base; Global change; Global studies; Climate change; Energy; Sustainability

Article

26 January 2024

A Lightweight Visual Navigation and Control Approach to the 2022 RoboMaster Intelligent UAV Championship

In this paper, an autonomous system is developed for drone racing. On account of their vast consumption of computing resources, the methods for visual navigation commonly employed are discarded, such as visual-inertial odometry (VIO) or simultaneous localization and mapping (SLAM). A series of navigation algorithms for autonomous drone racing, which can operate without the aid of the information on the external position, are proposed: one for lightweight gate detection, achieving gates detection with a frequency of 60 Hz; one for direct collision detection, seeking the maximum passability in-depth images. Besides, a velocity planner is adopted to generate velocity commands according to the results from visual navigation, which are enabled to perform a guidance role when the drone is approaching and passing through gates, assisting it in avoiding obstacles and searching for temporarily invisible gates. The approach proposed above has been demonstrated to successfully help our drone passing-through complex environments with a maximum speed of 2.5 m/s and ranked first at the 2022 RoboMaster Intelligent UAV Championship.

Keywords: MAV; Drone racing; Autonomous drone

Editorial

25 January 2024

Article

23 January 2024

Analysis of a σ54 Transcription Factor L420P Mutation in Context of Increased Organic Nitrogen Tolerance of Photofermentative Hydrogen Production in Cereibacter sphaeroides Strain 2.4.1 Substrain H2

Photofermentative hydrogen production with non-sulfur purple bacteria like Cereibacter sphaeroides (formerly Rhodobacter sphaeroides) is a promising and sustainable process to convert organic waste into the energy carrier hydrogen gas. However, this conversion is inhibited by elevated organic nitrogen concentrations in the substrate, which limits its applicability to nitrogen-poor organic waste. We present genomic and transcriptomic insights into a substrain of Cereibacter sphaeroides strain 2.4.1 that shows unexpected high levels of photofermentative hydrogen evolution when fed with glutamate. Genome sequencing revealed 222 single nucleotide variances (SNVs) between the reference genome of C. sphaeroides strain 2.4.1 and the analyzed substrain H2. These affect 61 protein coding genes. A leucine-proline exchange is present in the σ54 factor (rpoN2 gene), a global hydrogen and nitrogen metabolism regulator. We propose a model how this mutation alters DNA-binding properties that explain the unexpected organic nitrogen tolerance of hydrogen production. Transcriptomic analyses under varying glutamate concentrations support this finding. Thus, we present the first thorough genomic and transcriptomic analysis of a Cereibacter strain that shows promising metabolic characteristics for biotechnological hydrogen gas production from organic waste. These results suggest a potential target for strain optimization. Possibly, our key finding can be transferred to other hydrogen producing microorganisms.

Keywords: Bioenergy; Photobiological hydrogen production; Re-sequencing; Transcriptomic analysis; RNASeq; σ54; RpoN; Sigma factor

Comment

19 January 2024

New Geographical (Im)materialities in Rural Spaces for a Renewed Countryside in the Global North. Some Key Comments in the Rural Geography Debate

From the point of view of the new (im)materialities and the relevance of vernacular house in the process of rural change and restructuring, this contribution comments some possible innovative ways of research in rural studies. The objective of the study is to bring the attention about the relevance of vernacular houses in the process of global rural change and restructuring and their particular expressions in localities and vernacular houses. The methodology in qualitatively based on auto-biographical and ethnographical research based in three houses of study in a marginal rural area of central Spain. The main conclusions suggest a process of hybridization of people and vernacular houses with two different circuits: new comers and traditional populations.

Keywords: Territory; Materialism; Place; Encounter; Hybridity; Community; Rural geography

Review

17 January 2024

A Review on Significant Role of Additive Manufacturing in Biomedical Applications

The rapid development of manufacturing sector has created a platform for implementing novel technologies such as additive manufacturing (AM). AM or 3D printing, has generated a lot of interests in biomedical applications during the last decade with a variety of novel printed polymeric materials. 3D printing fabricates 3D object with layer-by-layer processing through computer-controlled programming software. It has innumerable applications including electronics, aerospace engineering, automobile industry, architecture and medical sectors. One of the most demanding sectors of 3D printing is biomedical engineering applications such as medicines, drug delivery system, surgical instruments, orthopedics, scaffolds, implants etc. The clinical ramifications of AM-made healthcare goods are being catalyzed by recent developments in biomaterials. This review paper aims to explain the concept of 3D printing and its significance in developing polymeric materials for biomedical applications. An inclusive survey has been conducted on the various techniques involved in printing the biomedical devices. The proper selection of polymeric materials is important for biomedical applications, especially from 3D printing point of view and this vital parameter has been considered in this review paper. According to our findings, more breakthroughs in biomaterials, are required for the success and expansion of AM technology in the biomedical applications.

Keywords: Additive manufacturing or 3D printing; Biomedical engineering; Polymer materials; Orthopedics; Scaffolds; Implants

Editorial

17 January 2024

Article

16 January 2024

Purification the Solvent for the Production of High-Density Polyethylene

The adsorption purification of gasoline fraction with NaX zeolites as a solvent for the production of high-density polyethylene at a large pilot plant with a layer height of the adsorbent layer from 1 to 8 m is considered. Removal of impurities of aromatic and unsaturated hydrocarbons, organosulfur impurities and water ensured the production of high-quality polyethylene. The main characteristics of the adsorption process (the dynamic activity of zeolite NaX, the length of the mass transfer zone) in a wide range of flow rates of the cleaned raw materials are determined, allowing the calculation of the adsorber without applying the principles of large-scale transition. 

Keywords: High-density polyethylene; Pilot plant; Adsorption; Zeolites; Mass transfer zone length
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