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Study of relationship between motion of mechanisms in gas operated weapon and its shock absorber

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Defence Technology（防务技术） 2024年第3期33卷 42-54页

作者： Jiri Balla Roman Vitek Dung Nguyen Van Zbynek Krist Hung Nguyen Van Department of weapons and Ammunition University of Defence BrnoCzech Republic Department of weapons Le Quy Don Technical UniversityHanoiViet Nam Department of Design and Special Engineering Alexander Dubcek University of TrencinSlovakia

The article deals with the motion of the breech block carrier and the weapon casing of an automatic weapon mounted on a flexible carriage and the base of the *** works,which did not consider the dynamic properties of the base of the weapon,did not allow to reconcile the calculated and experimental results of the weapon casing displacement when shooting from firing *** the analysis of the motion of individual parts,the methods of mathematical modelling and firing experiments using a high-speed camera were *** show the best accord with experiment when modelling the system with 4 degrees of *** oscillation of the system regarding the movement of the breech block carrier and the weapon casing was investigated under changed conditions of rate of fire,the use of a muzzle brake and different types of shock *** velocities and displacements of the weapon casing and the breech block carrier at different values of the impulse of the gases to the breech block carrier were determined.

关键词： Shock absorber Gas-operated weapon Force-impulse diagram Recoil system Breech block carrier

Metabolic engineering and genome editing strategies for enhanced lipid production in microalgae

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BIOCELL 2024年第8期48卷 1181-1195页

作者： ANJANI DEVI CHINTAGUNTA SAMUDRALA PRASHANT JEEVAN KUMAR NUNE SATYA SAMPATH KUMAR Department of Biotechnology Vignan’s Foundation ScienceTechnology and ResearchVadlamudiAndhra Pradesh522213India ICAR-directorate of Floricultural research Pune412307India

Depleting global petroleum reserves and skyrocketing prices coupled with succinct supply have been a grave concern,which needs alternative sources to conventional *** microalgae have been explored for enhanced lipid production,leading towards biodiesel *** microalgae have short life cycles,require less labor,and space,and are easy to scale ***,the primary source of lipids needed to produce biodiesel,is accumulated by most *** article focuses on different types of oleaginous microalgae,which can be used as a feedstock to produce *** biosynthesis in microalgae occurs through fatty acid synthesis and TAG synthesis ***-depth discussions are held regarding other efficient methods for enhancing fatty acid and TAG synthesis,regulating TAG biosynthesis bypass methods,blocking competing pathways,multigene approach,and genome *** most potential targets for gene transformation are hypothesized to be a malic enzyme and diacylglycerol acyltransferase while lowering phosphoenolpyruvate carboxylase activity is reported to be advantageous for lipid synthesis.

关键词： Oleaginous microalgae Biodiesel TAG synthesis Metabolic engineering Genome editing

Carbon-based materials with combined functions of thermal management and electromagnetic protection: Preparation, mechanisms, properties, and applications

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Nano research 2024年第3期17卷 883-903页

作者： Junwei Yue Yiyu Feng Mengmeng Qin Wei Feng School of materials Science and Engineering and Tianjin Key Laboratory of Composite and Functional materials Tianjin UniversityTianjin 300350China

The proliferation of high-power,highly informationized,and highly integrated electronic devices and weapons equipment has given rise to increasingly conspicuous issues about electromagnetic(EM)pollution and thermal *** issues,in turn,impose constraints on the performance of such equipment and jeopardize personnel *** materials,owing to their diverse and modifiable structures,offer adjustable thermal and electric conductivity,rendering them highly promising for applications in fields such as thermal management and EM protection which have garnered extensive research and *** pursuit of integrated device and equipment development has elevated the demand for multifunctional materials,prompting significant research into carbon-based composite materials that include both thermal management and EM protection ***,there are no relevant reviews on this topic at ***,this work consolidates research findings from recent years on carbon matrix composites exhibiting dual attributes of thermal management and EM *** attributes include thermally conductive electromagnetic interference(EMI)shielding materials,thermally insulating EMI shielding materials,thermally conductive EM wave(EMW)absorbing materials,and thermally insulating EMW absorbing *** paper elucidates the fundamental principles underpinning thermal conduction,thermal insulation,EMW absorbing,and EMI ***,it engages in discussions surrounding areas of contention,design strategies,and the functional properties of various material ***,the paper concludes by presenting the challenges encountered and potential research strategies about composites endowed with both thermal management and EM protection functionalities,while also envisaging the development of novel multifunctional EM protection materials.

关键词： carbon-based composites electromagnetic interference shielding microwave absorption thermal conduction thermal insulation

Modeling Study of the Evolution of the Climate Crisis over Time

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Open Journal of Applied Sciences 2024年第2期14卷 330-342页

作者： Victor Rogelio Tirado Picado directorate of research and University Extension American University (UAM) Managua Nicaragua

The research proposal has the following scope. In relation to the general objective, the aim is to model the evolution of the climate crisis over time taking as variables global warming, greenhouse gases, atmospheric temperature and ocean temperature, as well as the continuity of the natural phenomena in terms of their measurement, temporality and projection. To achieve the above, the description of the following specific objectives is proposed: - Identify the variables corresponding to the climate crisis, their relationship and correlation between them;- Develop projection models with mathematical and statistical arrangements to project them in a given time and, in this way, - Propose mitigation measures for different unfavorable scenarios. The main variables that are currently directly linked to Climate Change are: CO2, the atmospheric index, precipitation, temperature and wind speed. The correlation that exists between climatic elements is very high, both in historical behavior and projected behavior for 2035, their correlation is estimated at 0.90, 0.95, 0.93 and 91 respectively. The mathematical models used to manipulate the historical and projected analysis of the variables studied: are the normal arrangements, this ensures that the values can be used on a common scale;Then there is the analysis of the historical variables using the linear trend, and finally there is the analysis of the variables projected to the year 2035 using the polynomial trend. In both situations, the direct relationship of greenhouse gases, mainly CO2, is directly related to the variations of the variables over time, which is a very worrying result because we can no longer talk about climate change, but rather about CLIMATE CRISIS. To a large extent, a change in the paradigm of exploitation of the resources of our mother earth is required. Alert in an SOS manner to the great powers, which make reasonable use of technology, for this attenuation measures are proposed

关键词： Climate Crisis Model Climatic Factors Evolution Temperature

Direct-Seeded Rice: Genetic Improvement of Game-Changing Traits for Better Adaption

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Rice science 2024年第4期31卷 417-433页

作者： Priyanka NEGI Jagadish RANE Rajendra Sadashiv WAGH Tukaram Jayaram BHOR Dipti Digambar GODSE Priyanka JADHAV C.ANILKUMAR Dasari SREEKANTH K.SAMMI REDDY Sharad Ramrao GADAKH K.M.BORAIH C.B.HARISHA P.S.BASAVARAJ Indian Council of Agricultural research(ICAR)-National Institute of Abiotic Stress Management Baramati 413115India Mahatma Phule Krishi Vidyapeeth Rahuri 413722India ICAR-Central Institute for Arid Horticulture Bikaner 334006India ICAR-National Rice research Institute Cuttack 753006India ICAR-directorate of Weed research Jabalpur 482004India Dr.Panjabrao Deshmukh Krishi Vidyapeeth Akola 444104India

The sustainability of rice production continues to be a subject of uncertainty and inquiry attributed to shifts in climatic conditions. In light of the impending climate change crisis and the high labor and water costs accompanying it, direct-seeded rice(DSR) is unquestionably one of the most practical solutions. Despite its resource and climate-friendly advantages, early maturing rice faces weed competitiveness and seedling establishment challenges. Resolving these issues is crucial for promoting its wider adoption among farmers, presenting it as a more effective sustainable rice cultivation method globally. Diverse traditional and contemporary breeding methods are employed to mitigate the limitations of the DSR approach, leveraging advanced techniques such as speed breeding and genome editing. Focusing on key traits like mesocotyl length elongation, early seedling vigor, root system architecture, and weed competitiveness holds promise for transformative improvements in DSR adaptation at a broader scale within farming communities. This review aims to summarize how these features contribute to increased crop production in DSR conditions and explore the research efforts focusing on enhancing DSR adaptation through these traits. Emphasizing the pivotal role of these game-changing traits in DSR adaptation, our analysis sheds light on their potential transformative impact and offers valuable insights for advancing DSR practices.

关键词： climate change direct-seeded rice aerobic rice early vigor trait

A Comprehensive Systematic Review: Advancements in Skin Cancer Classification and Segmentation Using the ISIC Dataset

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2131-2164页

作者： Madiha Hameed Aneela Zameer Muhammad Asif Zahoor Raja Department of Computer Sciences Pakistan Institute of Engineering and Applied SciencesNilore50700Islamabad Future Technology research Center National Yunlin University of Science and TechnologyDouliou64002TaiwanChina directorate of IT Services University of GujratGujrat50700Pakistan

The International Skin Imaging Collaboration(ISIC)datasets are pivotal resources for researchers in machine learning for medical image analysis,especially in skin cancer *** datasets contain tens of thousands of dermoscopic photographs,each accompanied by gold-standard lesion diagnosis *** challenges associated with ISIC datasets have spurred significant advancements,with research papers reporting metrics surpassing those of human *** cancers are categorized into melanoma and non-melanoma types,with melanoma posing a greater threat due to its rapid potential for metastasis if left *** paper aims to address challenges in skin cancer detection via visual inspection and manual examination of skin lesion images,processes historically known for their *** notable advancements in machine learning and deep learning models,persistent challenges remain,largely due to the intricate nature of skin lesion *** review research on convolutional neural networks(CNNs)in skin cancer classification and segmentation,identifying issues like data duplication and augmentation *** explore the efficacy of Vision Transformers(ViTs)in overcoming these challenges within ISIC dataset *** leverage their capabilities to capture both global and local relationships within images,reducing data duplication and enhancing model ***,ViTs alleviate augmentation issues by effectively leveraging original *** a thorough examination of ViT-based methodologies,we illustrate their pivotal role in enhancing ISIC image classification and *** study offers valuable insights for researchers and practitioners looking to utilize ViTs for improved analysis of dermatological ***,this paper emphasizes the crucial role of mathematical and computational modeling processes in advancing skin cancer detection methodologies,highlighting their significance in improving algorithmic

关键词： Medical image skin cancer classification skin cancer segmentation international skin imaging collaboration convolutional neural network deep learning

Unscented Kalman filter for a low-cost GNSS/IMU-based mobile mapping application under demanding conditions

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Geodesy and Geodynamics 2024年第2期15卷 166-176页

作者： Mokhamad Nur Cahyadi Tahiyatul Asfihani Hendy Fitrian Suhandri Risa Erfianti Department of Geomatics Engineering Institut Teknologi Sepuluh NopemberSurabaya 6011Indonesia research Center of Marine and Earth Science Technology Directorate of Research and Community ServiceInstitut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Department of Mathematics Institut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Centre of Studies for Surveying Science&Geomatics Universiti Teknologi Mara(UiTM)Shah Alam 40450Malaysia

For the last two decades,low-cost Global Navigation Satellite System(GNSS)receivers have been used in various *** receivers are mini-size,less expensive than geodetic-grade receivers,and in high *** of these outstanding features,low-cost GNSS receivers are potentially poorer hardwares with internal signal processing,resulting in lower *** typically come with low-cost GNSS antenna that has lower performance than their counterparts,particularly for multipath ***,this research evaluated the low-cost GNSS device performance using a high-rate kinematic *** this purpose,these receivers were assembled with an Inertial Measurement Unit(IMU)sensor,which actively transmited data on acceleration and orientation rate during the *** position and navigation parameter data were obtained from the IMU readings,even without GNSS signals via the U-blox F9R GNSS/IMU device mounted on a *** research was conducted in an area with demanding conditions,such as an open sky area,an urban environment,and a shopping mall basement,to examine the device’s *** data were processed by two approaches:the Single Point Positioning-IMU(SPP/IMU)and the Differential GNSS-IMU(DGNSS/IMU).The Unscented Kalman Filter(UKF)was selected as a filtering algorithm due to its excellent performance in handling nonlinear system *** result showed that integrating GNSS/IMU in SPP processing mode could increase the accuracy in eastward and northward components up to 68.28%and 66.64%.Integration of DGNSS/IMU increased the accuracy in eastward and northward components to 93.02%and 93.03%compared to the positioning of standalone *** addition,the positioning accuracy can be improved by reducing the IMU noise using low-pass and high-pass *** application could still not gain the expected position accuracy under signal outage conditions.

关键词： LoW-cost GNSS GNSS/IMU Single Point Positioning-IMU(SPP/IMU) Differential GNSS-IMU(DGNSS/IMU) Unscented Kalman Filter(UKF) Outageconditions

Stock appraisal for Atlantic tripletail(Lobotes surinamensis;Bloch, 1790) in the Bay of Bengal, Bangladesh

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Journal of Oceanology and Limnology 2024年第05期 1683-1694页

作者： Suman BARUA Qun LIU Ahmed Fazley RABBY Md.Abdullah AL-MAMUN Xu CHEN Rokeya SULTANA Aidah BALOCH College of Fisheries Ocean University of China Department of Fisheries Ministry of Fisheries and Livestock Bangladesh Fisheries research Institute directorate of Secondary and Higher Education Ministry of Education Gwadar Development Authority

The Atlantic tripletail (Lobotes surinamensis) is a high revenue-generating fish species predominantly caught by mechanized artisanal fishers community and the most available member of its family in *** is a ground work of fish stock assessment study in the Bay of Bengal region to explore the life history parameters and associated biomass of this species,using three length-based approaches of TropFishR,the length-based Bayesian biomass estimation (LBB),and Froese’s lengthbased indicators (LBIs).An almost homogenous body growth pattern (b=3.07;R2=0.98) was observed in the length-weight relationship of *** life history parameters for tripletail,as determined by the von Bertalanffy Growth Function (VBGF) model,were L∞=113.36 cm and k=0.51/*** length converted catch curve (LCCC) yielded an estimation of the total mortality (Z=1.77/a),with the natural mortality estimated at (M=0.53/a) and the fishing mortality estimated at (F=1.24/a).But,the ratio of mortality(F/M=0.15) by LBB captured the non-fully exploited status of biomass (B/BMSY=2.1).LBI analysis indicated that the tripletail fishery’s spawning stock biomass is greater than the target and limit reference points,indicating a healthy state of biomass.

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Analysis of the effect of the 2021 Semeru eruption on water vapor content and atmospheric particles using GNSS and remote sensing

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Geodesy and Geodynamics 2024年第1期15卷 33-41页

作者： Mokhamad Nur Cahyadi Arizal Bawasir Syachrul Arief Amien Widodo Meifal Rusli Deni Kusumawardani Yessi Rahmawati Ana Martina Putra Maulida Hilda Lestiana Department of Geomatics Engineering Institut Teknologi Sepuluh NopemberSurabaya 60111Indonesia research Center of Marine and Earth Science-Technology Directorate of Research and Community ServiceInstitut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Geospatial Education and Training Division Geospatial Information Agency(BIG)Cibinong 16911Indonesia Department of Geophysics Engineering Institut Teknologi Sepuluh NopemberSurabaya 60111Indonesia Department of Mechanical Engineering Andalas UniversityPadang City 25175Indonesia Department of Economics Airlangga UniversitySurabaya 60286Indonesia research Center for Geological Resources National Research and Innovation AgencyJakarta 10340Indonesia

Mount Semeru,an active volcano in East Java,Indonesia,erupted on December 4,2021,following extreme rainfall that caused an avalanche of hot pyroclastic flows and *** tropospheric conditions and dominant particle components in the atmosphere can be monitored using Global Navigation Satellite System(GNSS)technology and remote sensing *** signal propagation delay in Precise Point Positioning(PPP)processing can be used to determine Zenith Tropospheric Delay(ZTD)and Precipitable Water Vapor(PWV)variables so that atmospheric conditions can be *** addition,by using remote sensing satellite data,it is possible to obtain rainfall data with high temporal resolution as well as the dominant particle and gas content values during *** the eruption period,the high value of PWV was dominated by the high intensity of precipitation during the rainy *** rainfall before the eruption caused activity inside the mountain to increase,which occurred in avalanche type *** from that,the atmosphere around Semeru was also dominated by SO_(2)content,which spreaded for tens of ***_(2)content began to be detected significantly by remote sensing sensors on December 7,*** this study,deformation and atmospheric monitoring were also carried out using low-cost GNSS at the Semeru Monitoring Station on September 9-15,*** results of the ZTD and ZWD values show the dominance of the wet component,which is directly proportional to rainfall activity in this period.

关键词： Semeru GNSS Water vapor Rainfall SO_(2)