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Design of a Novel Exoskeleton with Passive Magnetic Spring Self-locking and Spine Lateral Balancing

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Journal of Bionic Engineering 2024年第1期21卷 236-255页

作者： jhon F.Rodríguez-León Betsy D.M.Chaparro-Rico Daniele Cafolla Francesco Lago Eduardo Castillo-Castañeda Giuseppe Carbone Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada Unidad Querétaro MecatronicaInstituto Politécnico NacionalCerro Blanco 14176090 Colinas del CimatarioQuerétaroMexico Department of Mechanical Energy and Management EngineeringUniversity of CalabriaVia P.Bucci Cubo 46 C87036 RendeItaly Faculty of Science and Engineering Department of Computer ScienceSwansea UniversitySwanseaUK CESTER University of Cluj-NapocaCluj-NapocaRomania

This paper proposes a new upper-limb exoskeleton to reduce worker physical strain.The proposed design is based on a novel PRRRP(P-Prismatic;R-Revolute)kinematic chain with 5 passive Degrees of Freedom(DoF).Utilizing a magnetic spring,the proposed mechanism includes a specially designed locking mechanism that maintains any desired task posture.The proposed exoskeleton incorporates a balancing mechanism to alleviate discomfort and spinal torsional effects also helping in limb weight relief.This paper reports specific models and simulations to demonstrate the feasibility and effectiveness of the proposed design.An experimental characterization is performed to validate the performance of the mechanism in terms of forces and physical strain during a specific application consisting of ceiling-surface drilling tasks.The obtained results preliminarily validate the engineering feasibility and effectiveness of the proposed exoskeleton in the intended operation task thereby requiring the user to exert significantly less force than when not wearing it.

关键词： Assistive mechanism Exoskeleton Locking mechanism Bionic robot

Has global deforestation accelerated due to the COVID-19 pandemic?

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Journal of Forestry Research 2023年第4期34卷 1153-1165页

作者： Jonnathan Céspedes Janelle M.Sylvester Lisset Pérez-Marulanda Paula Paz-Garcia Louis Reymondin Mehran Khodadadi jhon J.Tello Augusto Castro-Nunez The Alliance of Bioversity International and International Center for Tropical Agriculture(CIAT) Km 17 Recta Cali-PalmiraCaliColombia Department of Geosciences and Natural Resource Management University of CopenhagenCopenhagenDenmark Leibniz Centre for Agricultural Landscape Research(ZALF) MünchebergGermany

As the COVID-19 pandemic unfolded,questions arose as to whether the pandemic would amplify or pacify tropical deforestation.Early reports warned of increased deforestation rates;however,these studies were limited to a few months in 2020 or to selected regions.To better understand how the pandemic infl uenced tropical deforestation globally,this study used historical deforestation data(2004–2019)from the Terra-i pantropical land cover change monitoring system to project expected deforestation trends for 2020,which were used to determine whether observed deforestation deviated from expected trajectories after the fi rst COVID-19 cases were reported.Time series analyses were conducted at the regional level for the Americas,Africa and Asia and at the country level for Brazil,Colombia,Peru,the Democratic Republic of Congo and Indonesia.Our results suggest that the pandemic did not alter the course of deforestation trends in some countries(e.g.,Brazil,Indonesia),while it did in others(e.g.,Peru).We posit the importance of monitoring the long-term eff ects of the pandemic on deforestation trends as countries prioritize economic recovery in the aftermath of the pandemic.

关键词： Deforestation COVID-19 Time series Terra-i Drivers of deforestation monitoring

Practical assessment of rock damage due to blasting

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International Journal of Mining Science and Technology 2019年第3期29卷 379-385页

作者： jhon Silva Tristan Worsey Braden Lusk Department of Mining Engineering University of KentuckyLexingtonKY 40508USA Department of Mining and Nuclear Engineering Missouri University of Science and TechnologyRollaMO 65409USA

Blasting is the most cost effective methodology to break rock for mining or civil engineering applications.A good production blast will break only the rock that is needed to be removed,leaving the host rock with minimal damage.The control of rock damage due to blasting is very important when it comes to mine or construction design,safety,and cost.Damage to the host rock due to a production blast could result in failures,overbreak and unstable ground.Knowing how far the fractures generated by a production blast will go into the host rock is a valuable tool for engineers to design a safe highwall while keeping the actual excavation close to the design.Currently,there are several methods available to predict damage due to blasting.The accuracy of many of these methods is questionable,and in most cases,the methodologies over predict the results.This often leads to inefficient mines and poor construction works.When the current methodologies are reviewed,each one presents sound approaches,but in many cases they also lack consideration of other variables that,according to the authors,need to be included when predicting blast damage.This paper presents a practical methodology to assess the rock damage from blasting by combining other methodologies.The proposed method allows consideration of more variables when compared to available methods,resulting in a more accurate rock damage assessment.The method uses the estimation of the generated levels of peak particle velocity with the distance from a production blast presented by Persson and Holmberg,the peak particle velocity damage ranges proposed by Forsyth and the relationship between the static compressive strength and dynamic compressive strength of rocks from Liu.The new methodology was validated using the data published in a large-scale study performed in granite by Siskind.

关键词： Blasting Fracture Fracture extension Peak particle velocity

Reliability analysis for mine blast performance based on delay type and firing time

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International Journal of Mining Science and Technology 2018年第2期28卷 195-204页

作者： Silva jhon Li Lifeng Gernand Jeremy M. Department of Mining Engineering University of KentuckyLexingtonKY 40506USA The Pennsylvania State University PA 16802USA

Mining blasts may be defined as the use of explosive charges in a controlled manner by following a tightly controlled timing sequence according to an assigned firing order. Changes of timing between charges may result in an altered firing order and failure of the blasting sequence, which can cause high vibration levels, poor fragmentation, and/or an undesirable rock mass movement direction. Despite the importance of timing in determining mine blast results, there exists a lack of methodologies or tools with which to assess performance of a complete blast based on delay type and timing sequence. This document applies reliability engineering principles to evaluate the performance of a mine blast. The analyses are based on test results of the accuracy and precision of electronic and pyrotechnic detonators for typical firing times used in a surface coal mine, but may be applied to a variety of mines and timing scenarios.

关键词： Blast Timing sequence Scatter Reliability Risk analysis Monte Carlo simulation

A Power-Aware Branch Predictor by Accessing the BTB Selectively

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Journal of Computer Science & Technology 2005年第5期20卷 607-614页

作者： Cheol Hong Kim Sung Woo Chung Chu Shik jhon Mobile System Laboratory Department of Electrical Engineering and Computer Science Seoul National University Seoul 151-742 Korea Department of Computer Science University of Virginia Charlottesville Virginia 22904 U.S.A.

Microarchitects should consider power consumption, together with accuracy, when designing a branch predictor, especially in embedded processors. This paper proposes a power-aware branch predictor, which is based on the gshare predictor, by accessing the BTB （Branch Target Buffer） selectively. To enable the selective access to the BTB, the PHT （Pattern History Table） in the proposed branch predictor is accessed one cycle earlier than the traditional PHT if the program is executed sequentially without branch instructions. As a side effect, two predictions from the PHT are obtained through one access to the PHT, resulting in more power savings. In the proposed branch predictor, if the previous instruction was not a branch and the prediction from the PHT is untaken, the BTB is not accessed to reduce power consumption. If the previous instruction was a branch, the BTB is always accessed, regardless of the prediction from the PHT, to prevent the additional delay/accuracy decrease. The proposed branch predictor reduces the power consumption with little hardware overhead, not incurring additional delay and never harming prediction accuracy. The simulation results show that the proposed branch predictor reduces the power consumption by 29-47%.

关键词： branch predictor BTB embedded processor low power design PHT

Involvement of sweet pepper Ca LOX2 in jasmonate-dependent induced defence against Western flower thrips

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Journal of Integrative Plant Biology 2019年第10期61卷 1085-1098页

作者： Sandeep J Sarde Klaas Bouwmeester jhon Venegas-Molina Anja David Wilhelm Boland Marcel Dicke Laboratory of Entomology Wageningen University P.O. Box 16 6700 AA Wageningen The Netherlands Laboratory of Phytopathology Wageningen University P.O. Box 16 6700 AA Wageningen The Netherlands Department of Bioorganic Chemistry Max Planck Institute for Chemical Ecology Hans-Knoll-Straβe 8 D-07745 Jena Germany

Insect herbivory can seriously hinder plant performance and reduce crop yield. Thrips are minute cell-content-feeding insects that are important vectors of viral plant pathogens, and are serious crop pests. We investigated the role of a sweet pepper (Capsicum annuum) lipoxygenase gene, CaLOX2, in the defense of pepper plants against Western flower thrips (Frankliniella occidentalis). This was done through a combination of in-silico, transcrip-tional, behavioral andchemicalanalyses.Our datashowthat CaLOX2 is involved in jasmonic acid (JA) biosynthesis and mediates plant resistance. Expression of the JA-related marker genes, CaLOX2 and CaPIN II, was induced by thrips feeding. Silencing of CaLOX2 in pepper plants through virus-induced gene silencing (VIGS) resulted in low levels of CaLOX2 transcripts, as well as significant reduction in the accumulation of JA, and its derivatives, upon thrips feeding compared to control plants. CaLOX2-silenced pepper plants exhibited enhanced susceptibility to thrips. This indicates that CaLOX2 mediates JA-dependent signaling, resulting in defenseagainstthrips. Furthermore,exogenous application of JA to pepper plants increased plant resistance to thrips, constrained thrips population development and made plants less attractive to thrips. Thus, a multidisciplinary approach shows that an intact lipoxygenase pathway mediates various components of sweet pepper defense against F. occidentalis.

关键词： Western flower thrips sweet pepper CaLOX2 jasmonate

Facial nerve monitoring in parotid gland surgery:Design and feasibility assessment of a potential standardized technique

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2023年第4期9卷 280-287页

作者： Carlos S.Duque Andrés F.Londoño Ana M.Duque jhon J.Zuleta Marcela Marulanda Lina M.Otálvaro Miguel Agudelo Juan P.Dueñas María F.Palacio Gianlorenzo Dionigi Hospital Pablo Tobón Uribe Departmento deCancerologíaMedellinColombia Clínica de Otorrinolaringología de Antioquia“Orlant” MedellínColombia Sección Otorrinolaringología Departamentode CirugíaFacultad de MedicinaUniversidadde AntioquiaMedellínColombia Hospital Pablo Tobón Uribe DirecciónCientíficaMedellinColombia Sección Cirugia de Cabeza y Cuello Departamento de CirugíaFacultad deMedicinaUniversidad de AntioquiaMedellinColombia Department of Internal Medicine IsraelMedical CenterNewarkNew JerseyUSA Departamento de Cirugía Clínica El RosarioEl TesoroMedellínColombia Sección Cabeza y Cuello Instituto deCancerologíaClínica Las Américas–AunaMedellínColombia Chirurgia Generale Capitanio AuxiologicoMilanItaly

Background:Even though the use of nerve monitoring during parotid gland surgery is not the gold standard to prevent damage to the nerve,it surely offers some advantages over the traditional approach.Different from thyroid surgery,where a series of steps in intraoperative nerve monitoring have been described to confirm not only the integrity but—most importantly—the function of the recurrent laryngeal nerve,in parotid gland surgery,a formal guideline to follow while dissecting the facial nerve has yet to be described.Methods:A five‐year retrospective study was done reviewing the intraoperative records of patients who underwent parotid gland surgery under neural monitoring.The operative findings regarding the neuromonitoring process,particularly in regard to the amplitude of two main branches,were revised.A literature search was done to search for guidelines to follow when a facial nerve loss of signal is encountered.Results:Fifty‐five patients were operated on using the Nim 3 Nerve Monitoring System(Medtronic);31 were female patients,and 47 patients had benign lesions.Minimum changes were observed in the amplitude records after a comparison was made between the first and the last stimulation.There were only three articles discussing the term loss of signal during parotid gland surgery.Conclusion:Today,no sufficient attention has been given to the facial nerve monitoring process during parotidectomy.This study proposes a formal guideline to follow during this procedure as well as an instruction to consider when a loss of signal is observed to develop a uniform technique of facial nerve stimulation.

关键词： amplitude facial nerve intraoperative neural monitoring latency loss of signal nerve monitoring parotid gland

A Characteristic Non-Reflecting Boundary Treatment in Lattice Boltzmann Method

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Chinese Physics Letters 2008年第6期25卷 1964-1967页

作者： KIM Dehee KIM Hyung Min jhon Myung S VINAY Ⅲ Stephen J. BUCHANAN John Department of Chemical Engineering Carnegie Mellon University 5000 Forbes Ave Pittsburgh PA 15213 USA Division of Mechanical System Design Engineering Kyonggi University Suwon Kyonggi-do Korea Bechtel Bettis Inc West Mifflin PA 15122 USA

在格子 Boltzmann 方法，骚乱在模拟的起始的阶段发展，腐烂特征主要取决于边界处理方法；象平衡和反冲计划那样的开的边界条件潜在地产生控制不了的骚乱。过多的骚乱在边界从非物理的思考波浪发源。在压制这些思考波浪的边界利用波浪... 详细信息

在格子 Boltzmann 方法，骚乱在模拟的起始的阶段发展，腐烂特征主要取决于边界处理方法；象平衡和反冲计划那样的开的边界条件潜在地产生控制不了的骚乱。过多的骚乱在边界从非物理的思考波浪发源。在压制这些思考波浪的边界利用波浪的符号的典型边界条件，以及他们在格子 Boltzmann 方法的实现，此处被介绍。我们的新奇边界处理方法的表演被三个不同数字实验验证有效地压制过多的骚乱。

关键词：栅格玻尔兹曼法非反射边界处理连续流体流动数值模拟

Implementation of ison iazid preventive therapy in southern Lima, Peru: an analysis of health center characteristics

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Infectious Diseases of Poverty 2021年第3期10卷 26-33页

作者： Roberto Zegarra-Chaponan Lily Victoria Bonadonna Courtney M.Yuen Martha Brigida Martina-Chavez jhon Zeladita-Huaman Universidad Maria Auxiliadora LimaPeru Wayne State University School of Medicine DetroitMlUSA Harvard Medical School BostonMAUSA. Universidad Nacional Mayor de San Marcos LimaPeru.

Background:Tuberculosis(TB)prevention through the use of preventive treatment is a critical activity in the elimination ofTB.In multiple settings,limited staffing has been identified as a barrier to managing preventive treatment for TB contacts.This study aims to determine how health center staffing,service type,and TB caseload affects implementation of isoniazid preventive therapy(IPT)forTB contacts in southern Lima.Methods:We conducted an ecological study in 2019 in southern Lima,Peru.Through the review of medical records,we identified contacts ofTB patients who initiated IPT during 2016-2018,and who were 0-19 years old,the age group eligible for IPT according to Peruvian guidelines.We assessed bivariate associations between health center characteristics(numbers of physicians and nurses,types of services available,annual TB caseload)and IPT initiation and completion using binomial logistic regression.Results:Among 977 contacts,69%took more than a week to start IPT and 41%did not complete IPT.For those who successfully completed IPT,58%did not complete full medical follow-up.There was no significant difference in IPT completion or adherence based on whether health centers had more physicians and nurses,more comprehensive services,or higherTB caseloads.Among contacts,female sex was associated with delay in initiating IPT(P=0.005),age 5-19 years old was associated with completion of IPT(P=0.025)and age<5 years old was associated with completion of clinical evaluations(P=0.041).Conclusions:There are significant gaps in IPT implementation in health centers of southern Lima,Peru,but insufficient staffing of health centers may not be responsible.Further research is needed to identify how IPT implementation can be improved,potentially through improving stafftraining or monitoring and supervision.

关键词： Contacts Chemotherapy Latent tuberculosis Children Adolescent