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Investigation of Student Nurses’Attitudes towards End-of-Life Care and Their Influencing Factors
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作者 Lei Peng Jingxian Wang +1 位作者 Jia Wang Qiangqiang Liu 《Open Journal of Nursing》 2024年第5期183-191,共9页
Background: This cross-sectional investigative study aimed to determine student nurses’ attitudes towards end-of-life care. Methods: This study used a descriptive research design with stratified sampling to survey st... Background: This cross-sectional investigative study aimed to determine student nurses’ attitudes towards end-of-life care. Methods: This study used a descriptive research design with stratified sampling to survey student nurses enrolled in one of four nursing colleges in China from January 2023 to December 2023. Student nurses’ general demographic and prior related information, attitudes towards death and attitudes towards end-of-life care were determined using a general information questionnaire, the Death Attitude Profile—Revised scale and the Professional End-of-Life Attitude Scale (PEAS), respectively. Results: The total PEAS score was 122.91 ± 16.123. Significant differences were noted in the attitude towards end-of-life care scores according to sources of end-of-life care knowledge (P Conclusions: Student nurses lacked an optimistic attitude towards end-of-life care, which was influenced by differences in the sources of end-of-life care knowledge. 展开更多
关键词 Nursing Students end-of-life Care ATTITUDE
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Naturally Nitrogen-Doped Biochar Made from End-of-Life Wood Panels for SO_(2) Gas Depollution
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作者 Hamdi Hachicha Mamadou Dia +3 位作者 Hassine Bouafif Ahmed Koubaa Mohamed Khlif Flavia Lega Braghiroli 《Journal of Renewable Materials》 EI 2023年第11期3807-3829,共23页
Reconstituted wood panels have several advantages in terms of ease of manufacturing,but their shorter life span results in a huge amount of reconstituted wood panels being discarded in sorting centers yearly.Currently... Reconstituted wood panels have several advantages in terms of ease of manufacturing,but their shorter life span results in a huge amount of reconstituted wood panels being discarded in sorting centers yearly.Currently,the most common approach for dealing with this waste is incineration.In this study,reconstituted wood panels were converted into activated biochar through a two-step thermochemical process:(i)biochar production using pilot scale fast pyrolysis at 250 kg/h and 450℃;and(ii)a physical activation at three temperatures(750℃,850℃ and 950℃)using an in-house activation furnace(1 kg/h).Results showed that the first stage removed about 66% of the nitrogen from the wood panels in the form of NO,NH3,and trimethylamine,which were detected in small amounts compared to emitted CO_(2).Compared to other types of thermochemical conversion methods(e.g.,slow pyrolysis),isocyanic acid and hydrogen cyanide were not detected in this study.The second stage produced activated biochar with a specific surface area of up to 865 m^(2)/g at 950℃.The volatile gases generated during activation were predominantly composed of toluene and benzene.This two-step process resulted in nitrogen-rich carbon in the form of pyrrolic and pyridinic nitrogen.Activated biochars were then evaluated for their SO_(2) retention performance and showed an excellent adsorption capacity of up to 2140 mg/g compared to 65 mg/g for a commercial activated carbon(889 m^(2)/g).End-of-life reconstituted wood panels and SO_(2) gas are problematic issues in Canada where the economy largely revolves around forestry and mining industries. 展开更多
关键词 end-of-life wood panels PYROLYSIS activation biochar and activated biochar N-doped carbons SO_(2)removal
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Learning from the Film “Mitorishi (Transition Doula)”—Application to Understanding the End-of-Life in a Gerontological Nursing Practice Course in Japan
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作者 Testuko Takaoka Atsuko Hatsumi +2 位作者 Miho Sugawara Yumi Takenouchi Sugako Fujinaga 《Open Journal of Nursing》 2023年第5期233-248,共16页
Purpose: This study aims to detail what nursing students learned from watching the film “Mitorishi”, which was used among the teaching materials in a gerontological nursing practice course in nursing education in Ja... Purpose: This study aims to detail what nursing students learned from watching the film “Mitorishi”, which was used among the teaching materials in a gerontological nursing practice course in nursing education in Japan, and demonstrate the applicability of using the film as an element relevant to the teaching of end-of-life care in Japan. Methods: The participants were fourth-year nursing students at University A who had watched the film “Mitorishi” during the course, had submitted a report on what they learned, and provided informed consent to the study participation. The reports submitted by the participants were used as data and analyzed qualitatively using the content analysis approach. Results: The analysis identified the following five categories (number of codes): Characteristics of life during the final days (9), Importance of views on life and death (3), Importance of end-of-life care (3), Assistance in preparation for the final days of life (13), and Understanding the profession of transition doula (9). Discussion: The five categories show that the students have learned about the “role of nurses at the time of end-of-life care” while “visualizing end-of-life care” and learning “preparedness for end-of-life care”. These findings suggest that using the film “Mitorishi” in the teaching curriculum is effective for learning about end-of-life care for older people. 展开更多
关键词 end-of-life Care Nursing Students Basic Nursing Education Transition Doula
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Study on plasma expansion model of primary discharge on spacecraft solar array
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作者 Dejie WEI Jianwen WU Liying ZHU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期87-95,共9页
In the space plasma environment, primary discharge may occur on the solar array and evolve into a destructive sustained arc, which threatens the safe operation of the spacecraft. Based on the plasma expansion fluid th... In the space plasma environment, primary discharge may occur on the solar array and evolve into a destructive sustained arc, which threatens the safe operation of the spacecraft. Based on the plasma expansion fluid theory, a new multicomponent plasma expansion model is proposed in this study, which takes into account the effects of ion species, ion number, initial discharge current, and Low Earth Orbit(LEO) plasma environment. The expansion simulation of single-component and multicomponent ions is carried out respectively, and the variations of plasma number density, expansion distance, and speed during the expansion process are obtained.Compared with the experimental results, the evolution of propagation distance and speed is closed and the error is within a reasonable range, which verifies the validity and rationality of the model. The propagation characteristics of the primary discharge on the solar array surface and the influence of the initial value on the maximum propagation distance and the propagation current peaks are investigated. This study can provide important theoretical support for the propagation and evolution of the primary discharge and the key behavior of the transition to secondary discharge on spacecraft solar array. 展开更多
关键词 primary discharge plasma expansion propagation characteristics spacecraft solar array
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Efficient cache replacement framework based on access hotness for spacecraft processors
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作者 GAO Xin NIAN Jiawei +1 位作者 LIU Hongjin YANG Mengfei 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第2期74-88,共15页
A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity... A notable portion of cachelines in real-world workloads exhibits inner non-uniform access behaviors.However,modern cache management rarely considers this fine-grained feature,which impacts the effective cache capacity of contemporary high-performance spacecraft processors.To harness these non-uniform access behaviors,an efficient cache replacement framework featuring an auxiliary cache specifically designed to retain evicted hot data was proposed.This framework reconstructs the cache replacement policy,facilitating data migration between the main cache and the auxiliary cache.Unlike traditional cacheline-granularity policies,the approach excels at identifying and evicting infrequently used data,thereby optimizing cache utilization.The evaluation shows impressive performance improvement,especially on workloads with irregular access patterns.Benefiting from fine granularity,the proposal achieves superior storage efficiency compared with commonly used cache management schemes,providing a potential optimization opportunity for modern resource-constrained processors,such as spacecraft processors.Furthermore,the framework complements existing modern cache replacement policies and can be seamlessly integrated with minimal modifications,enhancing their overall efficacy. 展开更多
关键词 spacecraft processors cache management replacement policy storage efficiency memory hierarchy MICROARCHITECTURE
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An impact sensitivity assessment method of spacecraft based on virtual exterior wall
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作者 Runqiang Chi Yuyan Liu +1 位作者 Diqi Hu Baojun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期142-157,共16页
The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft... The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit spacecraft.An impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational efficiency.This method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the spacecraft.The Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh quality.The influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and spacecraft.The results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the method.The PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size vs.flux relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft. 展开更多
关键词 Sensitivity OD/M spacecraft Virtual exterior wall
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Decoupling Algorithms for the Gravitational Wave Spacecraft
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作者 XueWang Weizhou Zhu +4 位作者 Zhao Cui Xingguang Qian Jinke Yang Jianjun Jia Yikun Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期325-337,共13页
The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precis... The gravitational wave spacecraft is a complex multi-input multi-output dynamic system.The gravitational wave detection mission requires the spacecraft to achieve single spacecraft with two laser links and high-precision control.Establishing one spacecraftwith two laser links,compared to one spacecraft with a single laser link,requires an upgraded decoupling algorithmfor the link establishment.The decoupling algorithmwe designed reassigns the degrees of freedomand forces in the control loop to ensure sufficient degrees of freedomfor optical axis control.In addressing the distinct dynamic characteristics of different degrees of freedom,a transfer function compensation method is used in the decoupling process to further minimize motion coupling.The open-loop frequency response of the systemis obtained through simulation.The upgraded decoupling algorithms effectively reduce the open-loop frequency response by 30 dB.The transfer function compensation method efficiently suppresses the coupling of low-frequency noise. 展开更多
关键词 Gravitational waves spacecraft laser acquisition decoupling algorithms dynamical model optical axis control
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Individualized Aromatherapy in End-of-Life Cancer Patients Care:A Case Report 被引量:3
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作者 Qian Liu Xiaohong Ning Lei Wang 《Chinese Medical Sciences Journal》 CAS CSCD 2018年第4期234-239,共6页
As one of the methods of palliative care,aromatherapy has been applied gradually in clinical nursing work in China in recent years.Through aromatherapy,terminal cancer patients can get not only relieves of physical sy... As one of the methods of palliative care,aromatherapy has been applied gradually in clinical nursing work in China in recent years.Through aromatherapy,terminal cancer patients can get not only relieves of physical symptoms,but also spiritual relaxation and peace,thus have improved quality of life at the end stage.In this paper,we report in detail about how aromatherapy was applied for symptom control in a cancer patient with unknown primary malignancy and multiple metastasis and its effects on the terminal life of this patient. 展开更多
关键词 AROMATHERAPY ESSENTIAL oil PALLIATIVE CARE end-of-life cancer
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Activity coefficients of NiO and CoO in CaO–Al_2O_3–SiO_2 slag and their application to the recycling of Ni–Co–Fe-based end-of-life superalloys via remelting 被引量:2
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作者 Xin Lu Takahiro Miki Tetsuya Nagasaka 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期25-36,共12页
To design optimal pyrometallurgical processes for nickel and cobalt recycling, and more particularly for the end-of-life process of Ni-Co-Fe-based end-of-life(EoL) superalloys, knowledge of their activity coefficien... To design optimal pyrometallurgical processes for nickel and cobalt recycling, and more particularly for the end-of-life process of Ni-Co-Fe-based end-of-life(EoL) superalloys, knowledge of their activity coefficients in slags is essential. In this study, the activity coefficients of NiO and CoO in CaO-Al_2O_3-SiO_2 slag, a candidate slag used for the EoL superalloy remelting process, were measured using gas/slag/metal equilibrium experiments. These activity coefficients were then used to consider the recycling efficiency of nickel and cobalt by remelting EoL superalloys using CaO-Al_2O_3-SiO_2 slag. The activity coefficients of NiO and CoO in CaO-Al_2O_3-SiO_2 slag both show a positive deviation from Raoult's law, with values that vary from 1 to 5 depending on the change in basicity. The activity coefficients of NiO and CoO peak in the slag with a composition near B =(%CaO)/(%SiO_2) = 1, where B is the basicity. We observed that controlling the slag composition at approximately B = 1 effectively reduces the cobalt and nickel oxidation losses and promotes the oxidation removal of iron during the remelting process of EoL superalloys. 展开更多
关键词 RECYCLING nickel cobalt end-of-life SUPERALLOYS activity coefficients REMELTING SLAG
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Living Conditions and Palliative Care Needs among End-of-Life Former Commercial Plasma Donors Affected with HIV/AIDS in Rural Henan of China 被引量:3
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作者 Yu SHENG ZE-QI QIU +2 位作者 YUN HE NAOMI JUNIPER YAN ZHANG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第4期279-286,共8页
Objective China began providing antiretroviral therapy to people living with HIV/AIDS (PLWHA) in 2003. This study was to investigate the living conditions, including quality of life and happiness, and need for palli... Objective China began providing antiretroviral therapy to people living with HIV/AIDS (PLWHA) in 2003. This study was to investigate the living conditions, including quality of life and happiness, and need for palliative care of end-of-life PLWHA in rural Henan. Methods One hundred end-of-life AIDS patients were selected from Weishi, Zhenping and Tanghe counties in Henan, using convenience sampling. The World Health Organization Quality of Life for HIV (WHOQOL-HIV) BREF Chinese Version was used to measure the quality of life and the Memorial University of Newfoundland Scale of Happiness (MUNSH) was employed to measure subjective welfare. Qualitative interviews and focus group discussions were undertaken to learn about the palliative care provided and the specific needs of the end-of-life patients. Results Patients’ overall quality of life was moderate (12.62±1.97). Highest scores were in the spirituality/religion/personal beliefs, higher than the average scores in the Chinese population (P0.01), while psychological (13.58±2.06) and environment (12.50±3.28) domain scores were similar to the latter (P0.05). Both independence (12.15±2.15) and physiological (14.04±3.16) domain scores were lower than the average of the people living with HIV/AIDS in other studies (P0.01); however, all were in the moderate range. The average MUNSH score was 21.00±6.20, which was also moderate. The in-depth interviews indicated that the Henan Provincial Government’s policy of treatment and care had a beneficial impact on end-of-life AIDS patients, although the care components could be improved. Conclusions Living conditions of the end-of-life AIDS patients were moderate, and the HIV/AIDS palliative care model used was beneficial to them. Care could be improved by assisting the family unit as a whole. 展开更多
关键词 Living conditions People living with HIV/ AIDS PLWHA end-of-life China Plasma donors
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Investigation on end-of-life electric and electronic equipment recycling and disposal system in China: legislation, education and dissemination 被引量:1
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作者 陈铭 《Journal of Central South University》 SCIE EI CAS 2005年第S2期148-152,共5页
The Chinese obsolete electric and electronic equipments (EEE) recycling and disposal system on the point of view of legislation, education and dissemination were discussed, because of the highly increasing volume of e... The Chinese obsolete electric and electronic equipments (EEE) recycling and disposal system on the point of view of legislation, education and dissemination were discussed, because of the highly increasing volume of electric and electronic products and that of its obsoletes today in China. The legislations and responsibilities of go- vernment, industry and consumer were discussed based on the balance of benefit and responsibility depending on the realization of their benefits in the whole life cycle of products and its status in the whole value chain. Not only the legislation and establishment of the so called “compulsory discarding system” will be a possible and effective solution to the difficulty of the obsolete collection and recycling for obsolete electric and electronic reclaiming industry, but also the education and dissemination. Education and dissemination were discussed as an important role which will emphasize the adjusting of policy and law on the development of electric and electronic industry production and its reclaiming. The education of stockholders’ environmental responsibility and the advocating of responsibility sharing should be implement for industry and consumer. Chinese EEE industry should emphasize the control of natural source, and should implement the environmental benign design in their production, such as design for dismantling, no dismantling, thermal treatment and green design. The perspectives for the way to advocate a harmonic society for Chinese people were described. 展开更多
关键词 end-of-life EEE LEGISLATION EDUCATION RECYCLING
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A model for end-of-life vehicles management based on green manufacturing 被引量:2
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作者 Aman CHITRAKAR 《Journal of Chongqing University》 CAS 2006年第1期1-7,共7页
Like any industrial product, the vehicles also do have end of their service lives and ultimately result in end-of-life vehicle (ELV) at a certain stage of the vehicle life. The concern of this paper is to make a gener... Like any industrial product, the vehicles also do have end of their service lives and ultimately result in end-of-life vehicle (ELV) at a certain stage of the vehicle life. The concern of this paper is to make a general review on ELV management process and present a model for ELV management on the basis of green manufacturing so as to reduce the environmental impact and minimize the resources loss due to the ELVs. The various phases of vehicle life cycle starting from design, manufacturing and utilization, occurrence of ELV and then the storage, depollution, dismantling and finally the shredding and post shredder material processing phases of ELV for the resources recovery, all of these phases need to be considered to give totality to the model, which makes end-of-life vehicles management more benign for environment, and more efficient for the usage of resources. 展开更多
关键词 end-of-life vehicles (ELVs) environmental impact resource loss green manufacturing
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End-of-life care in a cardiology department: have we improved? 被引量:1
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作者 Juan Rulz-Garcia Pablo Dlez-Villanueva +5 位作者 Ana Ayesta Vanessa Brufia Lourdes M Figueiras-Graillet Laura Gallego-Parra Francisco Fernandez-Aviles Manuel Martinez-Selles 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2016年第7期587-592,共6页
Background End-of-life care is not usually a priority in cardiology departments. We sought to evaluate the changes in end-of-life care after the introduction of a do-not-resuscitate (DNR) order protocol. Methods & ... Background End-of-life care is not usually a priority in cardiology departments. We sought to evaluate the changes in end-of-life care after the introduction of a do-not-resuscitate (DNR) order protocol. Methods & Results Retrospective analysis of all deaths in a cardiology department in two periods, before and after the introduction of the protocol. Comparison of demographic characteristics, use of DNR orders, and end-of-life care issues between both periods, according to the presence in the second period of the new DNR sheet (Group A), a conven- tional DNR order (Group B) or the absence of any DNR order (Group C). The number of deaths was similar in both periods (n = 198 vs. n = 197). The rate of patients dying with a DNR order increased significantly (57.1% vs. 68.5%; P = 0.02). Only 4% of patients in both periods were aware of the decision taken about cardiopulmonary resuscitation. Patients in Group A received the DNR order one day earlier, and 24.5% received it within the first 24 h of admission (vs. 2.6% in the first period; P 〈 0.001). All patients in Group A with an implantable cardioverter defibrillator (ICD) had shock therapies deactivated (vs. 25.0% in the first period; P = 0.02). Conclusions The introduction of a DNR order protocol may improve end-of-life care in cardiac patients by increasing the use and shortening the time of registration of DNR orders. It may also contribute to increase ICD deactivation in patients with these orders in place. However, the introduction of the sheet in late stages of the disease failed to improve patient participation. 展开更多
关键词 CARDIOLOGY Cardiopulmonary resuscitation end-of-life Palliative care
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Economy Analysis of a Recycle Model of End-of-Life Vehicle 被引量:1
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作者 QIN Ye(秦晔) +5 位作者 WANG Xiang(王翔) CHEN Ming(陈铭) WANG Cheng-tao(王成焘) 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第4期413-416,423,共5页
In order to evaluate recycle economy of end-of-life vehicles quantitatively,an economy model based on a recycle model of end-of-life vehicles and recycle cost analysis. With a practical example of recycling engines of... In order to evaluate recycle economy of end-of-life vehicles quantitatively,an economy model based on a recycle model of end-of-life vehicles and recycle cost analysis. With a practical example of recycling engines of end-of-life vehicles ,the validity of the recycle economy model and good recycle economy of the end-of-life vehicle engine were justified. It is concluded that ① remanufacture-ability of the part or component of the vehicles; ② the organization and management level of a recycle corporation; ③ policies and regulations of the government are crucial factors to raise the recycle economy of the end-of-life vehicle. 展开更多
关键词 end-of-life vehicle (ELV) recycle model economy model remanufacture-ability
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Sensitivity analysis of spacecraft in micrometeoroids and orbital debris environment based on panel method 被引量:3
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作者 Di-qi Hu Run-qiang Chi +1 位作者 Yu-yan Liu Bao-jun Pang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期126-142,共17页
To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft,it is necessary to optimize the design of the spacecraft.Spacecraft survivability assessment is the key technology in the optimal desi... To reduce the risk of mission failure caused by the MM/OD impact of the spacecraft,it is necessary to optimize the design of the spacecraft.Spacecraft survivability assessment is the key technology in the optimal design of spacecraft.Spacecraft survivability assessment includes spacecraft impact sensitivity analysis and spacecraft component vulnerability analysis under MM/OD environment.The impact sensitivity refers to the probability of a spacecraft encountering an MM/OD impact while in orbit.Vulnerability refers to the probability that each component of a spacecraft may fail or malfunction when impacted by space debris.Yet this paper mainly analyzes the impact sensitivity and proposes a spacecraft sensitivity assessment method under the MM/OD environment based on a panel method.Under this panel method,a spacecraft geometric model is discretized into small panels,and whether they are impacted by MM/OD or not is determined through the analysis of the shielding or shadowing relationships between panels.The number of impacts on each panel is obtained through calculation,and accordingly the probability of each spacecraft component encountering MM/OD impact can be acquired,thus generating the impact sensibility.This paper extracts data from the NASA’s ORDEM2000,the ESA’s MASTER8 as well as the SDEEM2015(Space Debris Environmental Engineering Model developed by HIT),and uses the PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)method to interpolate and fit the size-flux relationship of space debris.Compared with linear interpolation and cubic spline interpolation,the fitting results through the method are relatively more accurate.The feasibility of this method is also demonstrated through two actual examples shown in this paper,whose results are close to those from ESABASE,although there are some minor errors mainly due to different debris data input.Through the cross-check by three risk assessment software-BUMPER,MDPANTO and MODAOST-under standard operating conditions,the feasibility of this method is again verified. 展开更多
关键词 Shielding algorithm Panel method spacecraft Sensitivity
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End-of-life vehicle recycling based on disassembly
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作者 王翔 秦晔 +1 位作者 陈铭 王成焘 《Journal of Central South University》 SCIE EI CAS 2005年第S2期153-156,共4页
The end-of-life vehicle recycling was studied based on the disassembly. The end-of-life recycling and the disassembly were reviewed and discussed. A disassembly experiment of an end-of-life engine was carried out, whi... The end-of-life vehicle recycling was studied based on the disassembly. The end-of-life recycling and the disassembly were reviewed and discussed. A disassembly experiment of an end-of-life engine was carried out, which strictly recorded the process of dismantling. Based on the results, a model of the end-of-life recycling was presented. In this model, the end-of-life parts were classified by three ways which included to recycle directly, to recycle after remanufacturing and to discard. By using this model, the dismantling efficiency and the recycling rate can be improved. Also, it obtains a good result after used in a dismantling factory. 展开更多
关键词 end-of-life VEHICLE RECYCLING DISASSEMBLY
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Sliding-Mode-Based Attitude Tracking Control of Spacecraft Under Reaction Wheel Uncertainties 被引量:3
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作者 Wei Chen Qinglei Hu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第6期1475-1487,共13页
The attitude tracking operations of an on-orbit spacecraft with degraded performance exhibited by potential actuator uncertainties(including failures and misalignments) can be extraordinarily challenging. Thus, the co... The attitude tracking operations of an on-orbit spacecraft with degraded performance exhibited by potential actuator uncertainties(including failures and misalignments) can be extraordinarily challenging. Thus, the control law development for the attitude tracking task of spacecraft subject to actuator(namely reaction wheel) uncertainties is addressed in this paper. More specially, the attitude dynamics model of the spacecraft is firstly established under actuator failures and misalignment(without a small angle approximation operation). Then, a new non-singular sliding manifold with fixed time convergence and anti-unwinding properties is proposed, and an adaptive sliding mode control(SMC) strategy is introduced to handle actuator uncertainties, model uncertainties and external disturbances simultaneously. Among this, an explicit misalignment angles range that could be treated herein is offered. Lyapunov-based stability analyses are employed to verify that the reaching phase of the sliding manifold is completed in finite time, and the attitude tracking errors are ensured to converge to a small region of the closest equilibrium point in fixed time once the sliding manifold enters the reaching phase. Finally, the beneficial features of the designed controller are manifested via detailed numerical simulation tests. 展开更多
关键词 Actuator failures actuator misalignment angles finite time sliding mode control(SMC) spacecraft attitude tracking
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End-of-life vehicles processing,towards a thermal treatment of auto shredder residue
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作者 Thomas Baranger CHEN Ming WANG Lu 《机电工程》 CAS 2011年第4期385-391,共7页
All over the world,the management of End-of-life Vehicles(ELV) and Automobile Shredder Residue(ASR) is an increasing issue for the car industry.The setting up of several environmental directives,among others the notio... All over the world,the management of End-of-life Vehicles(ELV) and Automobile Shredder Residue(ASR) is an increasing issue for the car industry.The setting up of several environmental directives,among others the notion of extended producer responsibility,encourage car manufacturers to find alternatives solutions to waste disposal.For 2017,China aims for the recyclability and energy recovery of 95% of total weight of used cars,and in order to reach this rate,the development of some ASR thermal processes could be envisaged.With this research,an overview of ELV management was given and the different solutions about ASR thermal treatment were presented.It is showed that in spite of its big heterogeneity,the high heating value of ASR makes pyrolysis and gasification very interesting,compared to incineration or disposal of in landfills. 展开更多
关键词 end-of-life vehicles automobile shredder residue RECYCLING thermal treatment GASIFICATION PYROLYSIS
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A conceptual analysis of the meaning of comfort at the end-of-life using the Walker and Avant(2014)Framework
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作者 Yong-Chao Hou Fiona Timmins +1 位作者 Qian Zhou Ju-Zi Wang 《Frontiers of Nursing》 2021年第2期91-97,共7页
Objective:The aim of the authors is to clarify the concept of comfort at the end-of-life in order to support understandings of fundamental nursing care needed at this stage of healthcare.Methods:The Walker and Avant f... Objective:The aim of the authors is to clarify the concept of comfort at the end-of-life in order to support understandings of fundamental nursing care needed at this stage of healthcare.Methods:The Walker and Avant framework was applied to develop a deeper understanding of the concept of comfort at the end of life.Results:Five defining attributes of comfort in the end-of-life were identified and they are having a peaceful home-life environment,trust and consolation,proximity and social-cultural support,alleviation of suffering,and a process of integrated intervention by nurses.Conclusions:At the end-of-life patients commonly experience physical,psychological,social-cultural,and environmental discomfort.Patients’families also encounter significant challenges.However,their comfort needs are often secondary to that of the patient.Additionally,a lack of clarity exists regarding the holistic meaning of comfort at the end-of-life,which can largely be confined to understandings of physical comfort for the patient,with a limited understanding of addressing family/caregivers’needs.Therefore,this concept analysis may provide some guidance in this regard and also provides support toward a more integrated understanding of the concept. 展开更多
关键词 COMFORT end-of-life care concept analysis DEATH DYING
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Nurses towards End-of-Life Situations: Sympathy vs. Empathy
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作者 Jefferson Garcia Guerrero 《Open Journal of Nursing》 2019年第3期278-293,共16页
Background: Nurses providing end-of-life care play an important role in providing support to both the patient and his/her family during one of their most difficult time. Patients in this stage do not only require phys... Background: Nurses providing end-of-life care play an important role in providing support to both the patient and his/her family during one of their most difficult time. Patients in this stage do not only require physical care but emotional support as well. Aside from being a care provider, nurses should be able to utilize their knowledge in therapeutic communication in order for the patients and his/her family members to verbalize their feelings and concerns. Objective: The purpose of this study is to identify whether nurses project sympathy or empathy while providing end-of-life care. It also aims to determine their lived experiences while proving care at this stage. Methodology: This study utilized the mixed convergent parallel design wherein both the quantitative research and qualitative research were employed. Result and Discussion: A factor analysis was conducted on 12 items with maximum likelihood extraction method and oblique (Promax) rotation method. The Kaiser-Meyer-Olkin (KMO) measure verified the sampling adequacy for the analysis, KMO = 0.792 (“meritorious” according to Kaiser (1974)). Bartlett’s Test of Sphericity (χ2 (66) = 1007.294, p α = 0.881, sympathy α = 0.804, and cognitive empathy α = 0.728). Correlations among the factors were r = 0.315 for affective empathy and sympathy, r = 0.295 for sympathy and cognitive empathy, and r = 0.356 for affective empathy and cognitive empathy. Emergent key themes and subthemes are based on participants’ responses. The key themes are heart-touching moments of nurses in providing end-of-life care, challenges encountered by nurses in providing end-of-life care and adaptive strategies used by nurses to the challenges they face in providing end-of-life care. Conclusion: Most nurses during end-of-life care express affective empathy, followed by sympathy and lastly cognitive empathy. Nurses are encouraged to show and practice affective and cognitive empathy rather than using sympathy in caring patient and dealing with family member in the end-of-life situations. Despite the challenges that nurses faced, they are able to provide quality care by utilizing several adaptive strategies such as listening and understanding, showing empathy, providing holistic care, being spiritual and being aware of the role as caregiver. 展开更多
关键词 SYMPATHY EMPATHY end-of-life CARE CHALLENGES Adaptive Strategies
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