Non-Isolated Interleaved Hybrid Boost Converter for Renewable Energy Applications

DC-DC boost converters are necessary to extract power from solar panels. The output voltage from these panels is far lower than the utility voltage levels. One of the main functions of the boost converter is to provide a considerable step-up gain to interface the panel to the utility lines. There are several techniques used to boost the low panel voltage. Some of the issues faced by these topologies are a high duty ratio operation, complex design with multiple active switches and discontinuous input current that affects the power drawn from the panel. This paper presents a boost converter topology that combines the advantages of an interleaved structure, a voltage lift capacitor and a passive voltage multiplier network. A mathematical analysis of the proposed converter during its various modes of operation is presented. A 100 W prototype of the proposed converter is designed and tested. The prototype is controlled by a PIC16F18455 microcontroller. The converter is capable of achieving a gain of 10 without operating at extremely high duty ratios. The voltage stress of the switch is far lower than the maximum output voltage.

Design of the Capacitive Dual-Mass Micromechanical Gyroscope

Development of micromechanical inertial sensors have made it possible to use them in the navigation and motion control systems. This application area imposes strict requirements on sensors. One of the ways to meet the requirements and to improve the gyroscope characteristics is to apply a dual- or multi-mass architecture of a gyroscope sensing element. This paper presents the results of dual-mass micromechanical gyroscope with a measurement range of ±450°/s design. The complex design method, including simulation at the system level, model refinement based on the results of finite element modelling, and modelling of individual electronic blocks at the circuit level, is described.

Review of Recent Offshore Wind Turbine Research and Optimization Methodologies in Their Design

As international efforts to address climate change grow, an increasing number of countries and companies have put forward a clear “net zero” goal through accelerated renewable-energy development. As a renewable energy source, offshore wind energy has received particular attention from many countries and is a highly active research area. However, the design of offshore wind turbine structures faces challenges due to the large and complex design parameter space as well as different operational requirements and environmental conditions. Advanced optimization technology must be employed to address these challenges. Using an efficient optimization algorithm, it is possible to obtain optimized parameters for offshore wind turbine structures, balancing energy generation performance and the life of the floating wind turbine. This paper presents a review of the types and fundamental principles of several critical optimization technologies along with their application in the design process, with a focus on offshore wind turbine structures. It concludes with a discussion of the future prospects of optimization technology in offshore wind research.

Voter Confusion in Surabaya: The Problem of Ballot Design and Incompetence [Kebingungan Pemilih di Surabaya: Masalah Desain Kertas Suara dan Inkompetensi]

The simultaneous scheme in the 2019 elections in Indonesia caused voter confusion, especially in the legislative elections. Citizens who are confused and disappointed when voting candidates characterize the declining quality of representation in electoral democracy. This study aims to determine the factors of confusion among citizens when they are in the voting booth. The case study research was conducted in Surabaya by interviewing 54 residents after the general election using recalling questions and in-depth interviews. The results show that the voter confusion factor is the effect of the complex design of the 2019 legislative election ballot paper, the lack of socialization about election procedures, and the difficulty of respondents understanding the simultaneous election models. The competency category shows that voter confusion is the respondents' low interest in political discussions and inadequate political knowledge. These two competence issues affect the quality of voters' political participation. Voter confusion in Surabaya generally motivates the phenomena of incorrect and misleading voting.AbstrakSkema serentak dalam pemilu 2019 di Indonesia menimbulkan fenomena kebingungan pemilih, khususnya pada pemilihan legislatif. Warga yang bingung dan kecewa pada saat memilih kandidat mencirikan menurunnya kualitas representasi dalam demokrasi elektoral. Penelitian ini bertujuan untuk mendapatkan faktor-faktor kebingungan warga saat berada di bilik suara. Penelitian studi kasus dilakukan di Surabaya dengan mewawancarai 54 warga pasca pemilihan umum dengan menggunakan teknik recalling question dan deep interview. Hasil penelitian menunjukkan bahwa faktor kebingungan pemilih merupakan efek dari desain kertas suara pemilihan legislatif 2019 yang kompleks, minimnya sosialisasi mengenai tata cara pemilu, dan sulitnya responden memahami pemilihan model serentak. Kategori kompetensi menunujukkan bahwa kebingungan terjadi karena rendahnya ketertarikan responden dalam diskusi politik dan rendahnya pengetahuan politik. Dua masalah komptensi ini berefek pada kualitas partisipasi politik pemilih. Kebingungan pemilih di Surabaya secara umum memotivasi fenomena incorrect voting dan misleading voting.

CONTROL SYSTEM FOR NEEDLE INSERTION INTO THE PERIPHERAL VENOUS VESSEL

Предложен новый способ контроля введения инъекционной иглы в просвет вены на основе измерений электрического импеданса с помощью смешанной системы электродов, состоящей из биполярного и тетраполярного звеньев. Исследованы альтернативные схемы расположения электродов при проведении контроля венозной пункции биоимпедансным методом - они имеют более сложную конструкцию, используют дорогостоящие специализированные коаксиальные иглы, не позволяют однозначно определить факт прокола стенки венозного сосуда, нуждаются в дополнительной фильтрации регистрируемого сигнала с целью корректной интерпретации результата. Эффективность предложенной методики проверялась в ходе экспериментальных исследований на 5 добровольцах. Результаты экспериментов позволили идентифицировать 4 стадии нахождения инъекционной иглы относительно верхней конечности: нет касания, касание кожного покрова, нахождение под кожей коже, попадание в просвет вены. Идентификация положений инъекционной иглы происходит в реальном времени без дополнительной фильтрации регистрируемого сигнала. Метод позволяет обнаружить момент прокола стенки венозного сосуда стандартной инъекционной иглой, что в дальнейшем позволит сэкономить на изготовлении специализированных многослойных игольчатых электродов и внедрить данный способ контроля за проведением венепункции в медицинскую практику. Дальнейшее развитие предложенного подхода предполагает идентификацию двойного прокола вены, дифференцирование типа ткани в процессе введения иглы и исследование возможности определения типа кровеносного сосуда A new method for controlling the penetration of an injection needle into the vein based on measurements of electrical impedance using a mixed system of electrodes consisting of bipolar and tetrapolar parts is proposed. Alternative schemes for the arrangement of electrodes for monitoring venous puncture using the bioimpedance method have been investigated - they have a more complex design, use expensive specialized coaxial needles, do not allow to unambiguously determine the fact of a puncture of the venous vessel wall, require additional filtering of the recorded signal in order to correctly interpret the result. The effectiveness of the proposed technique was tested in experimental studies on 5 volunteers. The results of the experiments made it possible to identify 4 stages of finding the injection needle relative to the upper limb: no touching, touching the skin, being under the skin of the skin, getting into the lumen of the vein. Identification of the positions of the injection needle occurs in real time without additional filtering of the recorded signal. The method allows detecting the moment of puncture of the wall of a venous vessel with a standard injection needle, which in the future will save on the manufacture of specialized multilayer needle electrodes and introduce this method of monitoring venipuncture into medical practice. Further development of the proposed approach involves the identification of a double vein puncture, differentiation of tissue type during needle insertion, and investigation of the possibility of determining the type of blood vessel

Creative Environment in the Context of Coworking Center Design

The article is devoted to identifying the features of the creative environment in the context of the specifics of the space of the coworking center and to determine the basic design principles and means of its creation. The concept of "creative space" in the context of the specifics of the design of the coworking center has been clarified and supplemented. In this study, the concept of creative environment is considered by us as a subject-spatial environment, in the process of development and creation of which the designer takes into account not only the specifics of the philosophy of self-realization, but also tools to meet this need in anthropocentric approach. The study found that modern coworking centers, thanks to unique design approaches, are positioned as a favorable creative environment for the work of the creative class in the context of the implementation of new creative ideas. It is proved that functionality, artistic image, providing the necessary conditions for efficiency, ease of use, safety and aesthetic pleasure from being in the space of the coworking center and interaction with objects is achieved only through a systematic approach to design, which takes into account functional and technological and social -cultural factors. It is determined that the creation of a creative environment of a coworking center by a designer is the result of complex design - joint technical, aesthetic and artistic activities, the main property of which is anthropocentrism, ie human orientation. Accordingly, in the design process, the designer proceeds solely from human needs (in this case during work) to avoid unwanted adaptation of visitors to the coworking center to the environment created by him.

Establishment and Application of Ligation Reaction-Based Method for Quantifying MicroR-156b

Microribonucleic acids (miRNAs) play significant roles in the regulation of biological processes and in responses to biotic or abiotic environmental stresses. Therefore, it is necessary to quantitatively detect miRNAs to understand these complicated biological regulation mechanisms. This study established an ultrasensitive and highly specific method for the quantitative detection of miRNAs using simple operations on the ground of the ligation reaction of ribonucleotide-modified deoxyribonucleic acid (DNA) probes. This method avoids the complex design of conventional reverse transcription. In the developed assay, the target miRNA miR156b was able to directly hybridize the two ribonucleotide-modified DNA probes, and amplification with universal primers was achieved following the ligation reaction. As a result, the target miRNA could be sensitively measured even at a detection limit as low as 0.0001 amol, and differences of only a single base could be detected between miR156 family members. Moreover, the proposed quantitative method demonstrated satisfactory results for overexpression-based genetically modified (GM) soybean. Ligation-based quantitative polymerase chain reaction (PCR) therefore has potential in investigating the biological functions of miRNAs, as well as in supervising activities regarding GM products or organisms.

Combination of Terrestrial and Satellite Topography for Pipeline Engineering and Construction

A method consisting in an optimal combination of conventional topography from a terrestrial acquisition and satellite derived topography is presented. The solution recently implemented in the UAE for the engineering and the construction of a gas export pipeline allows significant cost reduction, time saving, and safety hazard reduction as fewer terrestrial operations are needed. The survey area is split into 2 sub-areas: area with infrastructures requiring a high accuracy is surveyed with terrestrial topographical acquisition methods such as GNSS receivers, the other one with desert conditions is mapped from satellite stereoscopic imagery. Stereoscopic mode refers to when the satellite sensor acquires two images of the same location taken from different angles. Using photogrammetric techniques, it produces a 3D elevation model of the area. The native satellite imagery allows a mapping of the surface features as well. Terrestrial and satellite datasets are finally merged and adjusted to provide engineering and construction contractors with a unique survey dataset. Terrestrial survey methods provide generally 5-10cm horizontal and vertical accuracies whereas satellite topography has accuracy of a few meters, so satellite topography must be controlled and adjusted from terrestrial ground control points which allow to reach an average 50cm absolute accuracy. This is good enough in desert areas with neither particular ground feature nor steep relief requiring complex design. Satellite acquisition has limitations: vegetation masking the ground, steep slopes and dense infrastructures. It is therefore necessary to combine conventional and satellite topography to meet engineering requirements. This is considered when defining the satellite and terrestrial survey areas. Beyond these limitations, this solution has strong advantages. Satellite grid resolution can be better (1-2m versus 5-10m for GNSS surveys). Acquisition and processing are faster (about 2 weeks versus a few weeks or months), and costs are from 10 to 100 times cheaper than conventional methods. No need for personnel and equipment on site, no management of logistics and permitting as well. Finally, it reduces safety hazards such as car accident, harsh weather, manual handling, etc. In addition, limiting the area to be surveyed with conventional equipment may avoid the need to mobilize Airborne photogrammetry or lidar systems usually operated by foreign companies. This limits complex Call for Tender, permitting management and give more opportunity to contract local companies. Satellite topography is widely used for preliminary studies, but the innovation here consists in an optimal combination of terrestrial and satellite datasets for engineering and construction purposes. This solution has however some limitations as it requires suitable conditions for satellite optical imagery acquisitions: no vegetation, limited cloud cover, smooth topography, and limited infrastructures. This is of interest basically in Middle east and North Africa.