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Sleep Quality and Emotional Adaptation among Freshmen in Elite Chinese Universities during Prolonged COVID-19 Lockdown:The Mediating Role of Anxiety Symptoms
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作者 Xinqiao Liu Linxin Zhang Xinran Zhang 《International Journal of Mental Health Promotion》 2024年第2期105-116,共12页
Under the effects of COVID-19 and a number of ongoing lockdown tactics,anxiety symptoms and poor sleep quality have become common mental health issues among college freshmen and are intimately related to their emotion... Under the effects of COVID-19 and a number of ongoing lockdown tactics,anxiety symptoms and poor sleep quality have become common mental health issues among college freshmen and are intimately related to their emotional adaptation.To explore this connection,this study gathered data from a sample of 256 freshmen enrolled in an elite university in China in September 2022.The association between sleep quality,anxiety symptoms,and emotional adaptation was clarified using correlation analysis.Additionally,the mediating function of anxiety symptoms between sleep quality and emotional adaptation was investigated using a structural equation model.The results reveal that:(1)Chinese elite university freshmen who were subjected to prolonged lockdown had poor sleep quality and mild anxiety symptoms;(2)a significant positive correlation between poor sleep quality and anxiety symptoms was identified;(3)anxiety symptoms were found to have a significant negative impact on emotional adaptation;(4)poor sleep quality had a negative impact on emotional adaptation through anxiety symptoms.This research makes a valuable contribution by offering insights into the intricate relationship between sleep quality and emotional adaptation among freshmen in elite Chinese universities during prolonged lockdown conditions,and it is beneficial for schools and educators to further improve school schedules and psychological health initiatives. 展开更多
关键词 COVID-19 pandemic sleep quality emotional adaptation anxiety symptoms lockdown FRESHMEN
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Increase in the functional capacity and quality of life among stroke patients by family caregiver empowerment program based on adaptation model 被引量:11
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作者 Kelana Kusuma Dharma Dedi Damhudi +1 位作者 Nelly Yardes Suhana Haeriyanto 《International Journal of Nursing Sciences》 2018年第4期357-364,共8页
Purpose:The family caregiver's role is an important influence factor of patient's adaptation behaviour and quality of life after stroke.The purpose of this research was to identify the effect of caregiver empo... Purpose:The family caregiver's role is an important influence factor of patient's adaptation behaviour and quality of life after stroke.The purpose of this research was to identify the effect of caregiver empowerment program based on the adaptation model(CEP-BAM)on functional capacity and quality of life of patients after stroke.Methods:This research was a quasi-experimental research with a pre-and post-test control group design.The total participants who completed the research were 80 patients and their families,40 participants in the intervention group and 40 participants in the control group.We conducted home visits to perform the intervention.The measurement of functional capacity and quality of life performed four times(pre-test and three times post-test).Data analysis was performed using the repeated measurement ANOVA or general linear model repeated measure(GLM-RM).Results:This research proves a significant difference in functional capacity and quality of life between the two groups and between pre-test and sixth months after intervention(P<0.05).The quality of life of the intervention group in the sixth month after intervention was better than that of the control group(33.40±3.65 vs 30.60±2.78)with a significant difference(P<0.05).Conclusion:It is concluded that CEP-BAM effectively increased patients'functional capacity and quality of life after a stroke in the sixth month after intervention. 展开更多
关键词 adaptation PSYCHOLOGICAL CAREGIVERS EMPOWERMENT Indonesia quality of life STROKE
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An optimal quality adaptation mechanism for end-to-end FGS video transmission
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作者 ER Gui-hua 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期119-124,共6页
In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS)stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quali... In this paper, we propose a novel optimal quality adaptation algorithm for MPEG-4 fine granular scalability (FGS)stream over wired network. Our algorithm can maximize perceptual video quality by minimizing video quality variation and increasing available bandwidth usage rate. Under the condition that the whole bandwidth evolution is known, we design an optimal algorithm to select layer. When the knowledge of future bandwidth is not available, we also develop an online algorithm based on the optimal algorithm. Simulation showed that both optimal algorithm and online algorithm can offer smoothed video quality evolution. 展开更多
关键词 MPEG-4 fine GRANULAR SCALABILITY (FGS) Video streaming Transmission quality adaptation
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Video quality based link adaptation for low latency video transmission over WLANs
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作者 FERR Pierre DOUFEXI Angela +2 位作者 CHUNG-HOW James NIX Andrew BULL David 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第5期847-856,共10页
Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes, each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in ... Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes, each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in the literature either maximise the error-free data throughput based on channel conditions or are based on the number of failed transmissions. However, these algo- rithms do not take into account the content of the data stream and strongly rely on the use of Automatic Repeat Requests (ARQs). Low latency video applications such as real-time video transmission may require no retransmission, or only a limited number of retrans- missions. Moreover, completely error-free communication is not essential, especially if robust video compression techniques are applied. In such scenarios, improved decoded video quality can be obtained with a video stream transmitted at a higher bit rate using a higher link speed but with some degree of transmission error, rather than an error-free video stream at a lower bit rate using a lower link speed. In this work, we investigate a link adaptation scheme that improves the Quality of Service (QoS) for video transmission, based on the overall received video quality (Peak Signal to Noise Ratio, PSNR), rather than by maximising the error-free throughput. We also study a practical link adaptation approach that uses PER thresholds at the PHY layer. An empirical study showed that thresholds for switching from one mode to another are much lower (almost error free) than those currently used by throughput based schemes. We show that traditional link adaptation strategies are not appropriate for real-time video transmission with no retransmis- sion. Simulation results using the H.264 video compression standard over IEEE 802.11a are presented. 展开更多
关键词 Link adaptation Wireless LAN Video quality Peak Signal to Noise Ratio (PSNR) Packet Error Rate (PER)
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Role of mitochondrial quality control in exercise-induced health adaptation 被引量:1
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作者 Hu DING Zi-yi ZHANG +1 位作者 Jing-wen ZHANG Yong ZHANG 《中国应用生理学杂志》 CAS CSCD 2013年第6期543-553,共11页
Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is ... Long-term endurance training or physical activity has been confirmed not only to improve physical performance, but to bring about an obvious beneficial effect on human health; however, the mechanism of this effect is not clear. The most studied health adaptations in skeletal muscle response to endurance exercise are increased muscle glycogen level and insulin sensitivity, fiber type transformation toward oxidative myofibers, and increased mitochondrial content/function. Mitochondria are dynamic organelles in eukaryotic cells critical in physical performance and disease occurrence. The mitochondrial life cycle spans biogenesis, maintenance, and clearance. Exercise training may promote each of these processes and confer positive impacts on skeletal muscle contractile and metabolic functions. This review focused on the regulation of these processes by endurance exercise and discussed its potential benefits in health and disease. We presented evidence suggesting that exercise training potentiates not only the biogenesis of mitochondria but also the removal of old and unhealthy mitochondria through mitochondrial quality control. 展开更多
关键词 人体健康 质量控制 线粒体 运动性 耐力训练 胰岛素敏感性 物理性能 疾病发生
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Investigation of Adaptive Multi-Rate Link Adaptation of 3G System
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作者 费泽松 万蕾 +1 位作者 赵胜辉 匡镜明 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期369-374,共6页
In term of the features of 3G system, a novel AMR link adaptation strategy for 3G system is proposed. The impacts of AMR codec modes and power control on traffic quality of service are taken into account in the strate... In term of the features of 3G system, a novel AMR link adaptation strategy for 3G system is proposed. The impacts of AMR codec modes and power control on traffic quality of service are taken into account in the strategy at the same time. By synthetically comparing the signal-to-interference ratio value with the switching threshold and comparing the transmission power with its threshold, radio resource management can always keep each link on its proper codec mode with the corresponding optimal power level to achieve both robust speech quality and link capacity enhancement. Based on the WCDMA FDD uplink link-level simulation platform, AMR link adaptation platform is constructed. Simulation results show that the algorithm can track the fast change of channel conditions and select the most robust codec mode, thus the synthetic speech quality of AMR is better than that of signal mode during a wide range of channel conditions. The result will provide a reference strategy for AMR link adaptation of 3G system. 展开更多
关键词 AMR link adaptation radio resource management quality of service 3GPP
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Using multivariate adaptive regression splines to develop relationship between rock quality designation and permeability 被引量:2
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作者 Mohsin Usman Qureshi Zafar Mahmood Ali Murtaza Rasool 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第4期1180-1187,共8页
The assessment of in situ permeability of rock mass is challenging for large-scale projects such as reservoirs created by dams,where water tightness issues are of prime importance.The in situ permeability is strongly ... The assessment of in situ permeability of rock mass is challenging for large-scale projects such as reservoirs created by dams,where water tightness issues are of prime importance.The in situ permeability is strongly related to the frequency and distribution of discontinuities in the rock mass and quantified by rock quality designation(RQD).This paper analyzes the data of hydraulic conductivity and discontinuities sampled at different depths during the borehole investigations in the limestone and sandstone formations for the construction of hydraulic structures in Oman.Cores recovered from boreholes provide RQD data,and in situ Lugeon tests elucidate the permeability.A modern technique of multivariate adaptive regression splines(MARS)assisted in correlating permeability and RQD along with the depth.In situ permeability shows a declining trend with increasing RQD,and the depth of investigation is within 50 m.This type of relationship can be developed based on detailed initial investigations at the site where the hydraulic conductivity of discontinuous rocks is required to be delineated.The relationship can approximate the permeability by only measuring the RQD in later investigations on the same site,thus saving the time and cost of the site investigations.The applicability of the relationship developed in this study to another location requires a lithological similarity of the rock mass that can be verified through preliminary investigation at the site. 展开更多
关键词 In situ permeability LIMESTONE SANDSTONE Lugeon Rock quality designation(RQD) Multivariate adaptive regression splines (MARS)
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Psychosocial adaptation and influencing factors among patients with chemotherapy-induced peripheral neuropathy 被引量:1
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作者 Xiao Zhou Dong-Yang Wang +2 位作者 Cai-Yan Ding Hui Liu Zhi-Qin Sun 《World Journal of Clinical Cases》 SCIE 2022年第15期4843-4855,共13页
BACKGROUND Chemotherapy-induced peripheral neuropathy(CIPN)is a severe and longlasting side effect caused by various anticancer agents that damage sensory,motor and autonomic nerves.It can cause maladaptive behaviors,... BACKGROUND Chemotherapy-induced peripheral neuropathy(CIPN)is a severe and longlasting side effect caused by various anticancer agents that damage sensory,motor and autonomic nerves.It can cause maladaptive behaviors,including disease severity,anxiety,depression,sleep disorders,falls,and social impairment.These disorders have physical,psychological and social effects on patients and can seriously influence their quality of life.AIM To investigate the current situation of psychosocial adaptation to the disease and its influencing factor in patients with CIPN.METHODS A convenience sampling method was used to select 233 patients with CIPN in our hospital from February to August 2021.In addition,a cross-sectional survey was conducted using a sociodemographic questionnaire,the Self-Report Psychosocial Adjustment to Illness Scale,and the European Organisation for the Research and Treatment of Cancer Quality of Life CIPN20(QLQ-CIPN20).Factors influencing psychosocial adaptation in patients with CIPN were analyzed by t-test or one-way analysis of variance,correlation analysis,multiple stepwise regression analysis,and structural equation models.RESULTS The psychosocial adaptation score of patients with CIPN was 52.51±13.18.Multivariate analysis showed that autonomic nerves,tumor stage,motor nerves,education level,availability of caregivers,semi-retirement status,CIPN grade were independent risk factors for patients with CIPN(P<0.05).Structural equation models showed that QLQ-CIPN20 mediated the relationship between CIPN grade,tumor stage,and psychosocial adaptation.CONCLUSION Patients with CIPN have poor psychosocial adaptation and are affected by a variety of physiological,psychological,and social factors.Patients’adaptive responses should be assessed,and targeted interventions implemented. 展开更多
关键词 Chemotherapy-induced peripheral neuropathy CANCER Peripheral neurotoxicity Psychosocial adaptation quality of life
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Two-Phase Rate Adaptation Strategy for Improving Real-Time Video QoE in Mobile Networks 被引量:3
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作者 Ailing Xiao Jie Liu +2 位作者 Yizhe Li Qiwei Song Ning Ge 《China Communications》 SCIE CSCD 2018年第10期12-24,共13页
With the popularity of smart handheld devices, mobile streaming video has multiplied the global network traffic in recent years. A huge concern of users' quality of experience(Qo E) has made rate adaptation method... With the popularity of smart handheld devices, mobile streaming video has multiplied the global network traffic in recent years. A huge concern of users' quality of experience(Qo E) has made rate adaptation methods very attractive. In this paper, we propose a two-phase rate adaptation strategy to improve users' real-time video Qo E. First, to measure and assess video Qo E, we provide a continuous Qo E prediction engine modeled by RNN recurrent neural network. Different from traditional Qo E models which consider the Qo E-aware factors separately or incompletely, our RNN-Qo E model accounts for three descriptive factors(video quality, rebuffering, and rate change) and reflects the impact of cognitive memory and recency. Besides, the video playing is separated into the initial startup phase and the steady playback phase, and we takes different optimization goals for each phase: the former aims at shortening the startup delay while the latter ameliorates the video quality and the rebufferings. Simulation results have shown that RNN-Qo E can follow the subjective Qo E quite well, and the proposed strategy can effectively reduce the occurrence of rebufferings caused by the mismatch between the requested video rates and the fluctuated throughput and attains standout performance on real-time Qo E compared with classical rate adaption methods. 展开更多
关键词 continuous quality of experience (QoE) model recurrent neural network(RNN) real-time video QoE improving dynamic adaptive streaming over HTTP (DASH)
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Research on the effects of family care degree on stigma and psychosocial adaptation among the patients with Parkinson’s disease 被引量:1
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作者 Yue-Yue He An-Chun Yin 《Frontiers of Nursing》 CAS 2021年第1期69-74,共6页
Objective:This study aimed to investigate the status quo of family care degree,stigma and psychosocial adaptation of the patients with Parkinson’s disease(PD),and discuss the effects of family care degree on stigma a... Objective:This study aimed to investigate the status quo of family care degree,stigma and psychosocial adaptation of the patients with Parkinson’s disease(PD),and discuss the effects of family care degree on stigma and psychosocial adaptation among the patients with PD.Methods:This study was conducted between September 2018 and April 2019 on patients with PD who were admitted to a Ter tiary Grade A hospital in Dalian city.A total of 246 PD patients were investigated by convenience sampling method using self-designed general information questionnaire,along with family care index(APGAR),24-item Stigma Scale for Chronic Illness(SSCI),and Psychosocial Adjustment Scale(PAS)for PD.And patients were divided into two groups according to the level of family care degree and compared with stigma and psychosocial adaptation.Results:The total score of family care for patients with PD was 6.97±2.46,family function was good in 132 cases(53.7%),moderate barrier in 92 cases(37.4%),and severe barrier in 22 cases(8.9%).The scores of stigma and psychosocial adaptability and their dimensions in the group with high degree family care were higher than the low degree group.Conclusions:The overall level of family care for PD patients was poor.Improving family care degree can help patients with PD to reduce stigma and improve psychosocial adaptation. 展开更多
关键词 Parkinson’s disease family care STIGMA psychosocial adaptability quality of life
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The Precise Methods for the Measurement of Collimator Hole Angulation and Center of Rotation of SPECT by Adaptive Quality Control Phantom 被引量:1
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作者 Hossein Zamani Zeinali Mehran Ataee +3 位作者 Hamid Ravanbakhsh Ehsan Masumi Goodarzi Samana Ghoreishi Gholamreza Raisali 《World Journal of Nuclear Science and Technology》 2014年第4期208-215,共8页
The Adaptive Quality Control Phantom (AQCP) is a computer-controlled phantom which positions and moves a radioactive source in the Field of View (FOV) of an imaging nuclear medicine device on a definite path to produc... The Adaptive Quality Control Phantom (AQCP) is a computer-controlled phantom which positions and moves a radioactive source in the Field of View (FOV) of an imaging nuclear medicine device on a definite path to produce a spatial distribution of gamma rays to perform QC Tests such as the Collimator Hole Angulation (CHA) and the Center of Rotation (COR) of Single Photon Emission Computer Tomography (SPECT). The collimator hole angulation for six collimators was measured using a point source and a computer-controlled cylindrical positioning system. In this method, the displacement of the image of a point source was examined as the AQCP was moving point source vertically away from the collimator face. The results of the high-accuracy measurement method of CHA show that the measurement accuracy for absolute angulation errors is better than ±0.024°. The Root Mean Square (RMS) of CHA for LEHR, LEHS and LEUHR collimators of SMV dual heads camera and LEGP, MEGP and HEGP of GE Millennium MG were evaluated to be 0.290°, 0.292°, 0.208°, 0.154°, 0.220° and 0.202°, respectively. It is to be added in this connection that the evaluated RMS of CHA for LEHR collimator with the distance variation from the collimator’s surface ±1 mm has been varied ±0.04 degree. A new method for the center of rotation assessment by AQCP is introduced and the results of this proposed method as compared with the routine QC test and their differences are discussed in detail. We defined and measured a new parameter called Dynamic Mechanical Error (DME) for applying the gantry motion correction. 展开更多
关键词 Nuclear Medicine adaptIVE quality Control PHANTOM COLLIMATOR HOLE Angulation Center of Rotation
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Linking Environmental Water Scarcity and Options for Adaptation in the MENA Region
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作者 Bachar Ibrahim Henry Mensah 《Journal of Water Resource and Protection》 2017年第4期378-392,共15页
Contamination of surface and underground water by sea level rise, surface runoff, and land use activities such as industrial and agricultural activities can lead to water scarcity. Water could be available and accessi... Contamination of surface and underground water by sea level rise, surface runoff, and land use activities such as industrial and agricultural activities can lead to water scarcity. Water could be available and accessible but not suitable for human use. In the Middle East and North Africa (MENA) region countries, the agriculture sector depends massively on water for farming activities, which consumes about 80% of the available water resources. In this context, the issue of environmental water scarcity is under highlighted, though the use of this term itself is still lacking in an international context (FAO). Meanwhile, the international goal of universal access to clean freshwater is included in global development targets (SDGs). This study provides some insights and deepens our understanding on environmental water scarcity, particularly MEN-A region countries. This review paper begins with an introduction to water scarcity and continues with a discussion of environmental issues associated with water scarcity in MENA region countries. Finally, we suggest some adaptive measures in two distinct areas such as agriculture sectors and policy makers and conclude that the lack of implementation of this particular term is hindering sustainable development in MENA region countries. 展开更多
关键词 adaptation MENA Climate Change WATER SCARCITY WATER quality Environment
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Battery Voltage Discharge Rate Prediction and Video Content Adaptation in Mobile Devices on 3G Access Networks
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作者 Is-Haka Mkwawa Lingfen Sun 《ZTE Communications》 2013年第1期44-50,共7页
According to Cisco, mobile multimedia services now account for more than half the total amount of Internet traffic. This trend is burdening mobile devices in terms of power consumption, and as a result, more effort is... According to Cisco, mobile multimedia services now account for more than half the total amount of Internet traffic. This trend is burdening mobile devices in terms of power consumption, and as a result, more effort is needed to devise a range of pow- er-saving techniques. While most power-saving techniques are based on sleep scheduling of network interfaces, little has been done to devise multimedia content adaptation techniques. In this paper, we propose a multiple linear regression model that predicts the battery voltage discharge rate for several video send bit rates in a VoIP application. The battery voltage dis- charge rate needs to be accurately estimated in order to esti- mate battery life in critical VoIP contexts, such as emergency communication. In our proposed model, the range of video send bitrates is carefully chosen in order to maintain an acceptable VoIP quality of experience. From extensive profiling, the empir- ical resuhs show that the model effectively saves power and pro- longs real-time VoIP sessions when deployed in power-driven adaptation schemes. 展开更多
关键词 QOE POWER mobile devices quality adaptation discharge rate
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Results of the Measurement of the Collimator Hole Angulation for Different Collimators of SPECT with Adaptive Quality Control Phantom
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作者 Hossein Zamani Zeinali Ehsan Masumi Goodarzi +5 位作者 Hamid Ravanbakhsh Ali Asgher Sardarpour Narjes Abagheri Mahabadi Soghra Moradkhani Fatemeh Dolatshah Davood Rahi 《Modern Instrumentation》 2012年第4期49-53,共5页
The Adaptive Quality Control Phantom (AQCP) is the computer-controlled phantom which positions and moves a radioactive source in the Field of View (FOV) of an imaging nuclear medicine device on a definite path to prod... The Adaptive Quality Control Phantom (AQCP) is the computer-controlled phantom which positions and moves a radioactive source in the Field of View (FOV) of an imaging nuclear medicine device on a definite path to produce any spatial distribution of gamma rays to perform the QC Tests such as the Collimator Hole Angulation (CHA) of Single Photon Emission Computer Tomography (SPECT). The collimator hole angulation for seven collimators were measured with the method by using a point source and computer-controlled cylindrical positioning. In this method the displacement of the image of a point source examined as the AQCP move point source vertically away from the collimator face. The results of the high-accuracy measurement method of CHA show that the measurement accuracy for absolute angulation errors is better than ±0.024°. The Root Mean Square (RMS) of CHA for LEHR, LEHS, LEUHR, MEGP-250, MEGP-300, MEGP-360 and HEPH collimators of SMV dual heads camera were measured to be 0.290°, 0.292°, 0.208°, 0.194°, 0.181°, 0.177°, 0.150°, respectively. The Root Mean Square (RMS) of CHA for LEGP, MEGP and HEGP collimators of GE Millennium MG were measured to be 0.154°, 0.220° and 0.202° respectively. It is to be added in this connection that the measured RMS of CHA for LEHR collimator with the distance variation from the collimator’s surface +/– 1 mm has been varied +/– 0.04 degree. 展开更多
关键词 Nuclear Medicine adaptIVE quality Control PHANTOM COLLIMATOR HOLE Angulation
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Evaluation of the Translation,Cross-cultural Adaptation and Properties of Measurement of the FACT-BMT Questionnaire
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作者 Thalissa Maniaes Ana Paula Carraro Indiara Soares Oliveira 《Journal of Pharmacy and Pharmacology》 2019年第1期1-14,共14页
Various questionnaires have been described which evaluate the quality of life in patients undergoing cancer treatment,but most were originally developed in English and have not been adequately validated for other lang... Various questionnaires have been described which evaluate the quality of life in patients undergoing cancer treatment,but most were originally developed in English and have not been adequately validated for other languages.To evaluate the process of translation and cross-cultural adaptation and the measurement properties of the Functional Assessment of Cancer Therapy-Bone Marrow Transplantation(FACT-BMT)questionnaire,a systematic review was conducted with two independent evaluators.The search for articles was carried out in four databases:MEDLINE,EMBASE,CINAHL and SCIELO,using the terms“questionnaire”,“quality of life”,“oncology”,and“valid”and their descriptors according to MeSH and DeCs.The searches yielded 6,877 studies,of which only three performed the stages of translation,cross-cultural adaptation,and evaluation of the measurement properties of the FACT-BMT questionnaire.The instruments in Arabic,Chinese,Korean and Portuguese showed and presented good methodological quality,but none of the four studies followed all the validation criteria for the questionnaire.The adapted versions of the FACT-BMT have methodological weaknesses in their process of translation and cross-cultural adaptation and evaluation of measurement properties,therefore the questionnaires possibly being used inadequately in other languages. 展开更多
关键词 FACT-BMT QUESTIONNAIRE quality of LIFE TRANSLATION CROSS-CULTURAL adaptation and measurement properties
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Dynamic multimedia stream adaptation and rate control for heterogeneous networks
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作者 SZWABE Andrzej SCHORR Andreas +1 位作者 HAUCK Franz J. KASSLER Andreas J. 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第z1期63-69,共7页
Dynamic adaptation of multimedia content is seen as an important feature of next generation networks and pervasive systems enabling terminals and applications to adapt to changes in e.g. context, access network, and a... Dynamic adaptation of multimedia content is seen as an important feature of next generation networks and pervasive systems enabling terminals and applications to adapt to changes in e.g. context, access network, and available Quality-of-Service(QoS) due to mobility of users, devices or sessions. We present the architecture of a multimedia stream adaptation service which enables communication between terminals having heterogeneous hardware and software capabilities and served by heterogeneous networks. The service runs on special content adaptation nodes which can be placed at any location within the network. The flexible structure of our architecture allows using a variety of different adaptation engines. A generic transcoding engine is used to change the codec of streams. An MPEG-21 Digital Item Adaptation (DIA) based transformation engine allows adjusting the data rate of scalable media streams. An intelligent decision-taking engine implements adaptive flow control which takes into account current network QoS parameters and congestion information. Measurements demonstrate the quality gains achieved through adaptive congestion control mechanisms under conditions typical for a heterogeneous network. 展开更多
关键词 STREAM adaptation quality-OF-SERVICE (QoS) HETEROGENEOUS networks Rate control MPEG-21 DIA
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我国城市幼儿园空间布局适配性的现状、成因与优化建议 被引量:2
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作者 蔡迎旗 崔财艳 +1 位作者 资明贵 张春艳 《学前教育研究》 北大核心 2024年第1期24-37,共14页
供需适配的幼儿园空间布局是促进学前教育资源均衡配置的关键举措,能有效推动学前教育高质量发展。本研究以我国中部地区某省会城市主城区759所幼儿园为例,运用地理信息分析工具中的核密度估计、最近邻指数等方法,分别从“有园上”“入... 供需适配的幼儿园空间布局是促进学前教育资源均衡配置的关键举措,能有效推动学前教育高质量发展。本研究以我国中部地区某省会城市主城区759所幼儿园为例,运用地理信息分析工具中的核密度估计、最近邻指数等方法,分别从“有园上”“入园近”“上好园”“园幼共生”四个维度对幼儿园空间布局是否存在错配的核心议题进行深入剖析。研究发现:该市部分幼儿园空间分布存在欠适配现象,且形成了空间与结构错配的问题,其主要原因是资源投入层面的财政失衡、需求提出层面的逐优心理和城市规划层面的建设滞后。本文建议通过构建数字化管理平台、优化供需对接机制、加强配套园治理、加大治薄扶弱补缺的力度等措施,推动幼儿园空间布局从错配到适配的转换,从而促进区域学前教育公共服务一体化和高质量发展。 展开更多
关键词 幼儿园 空间布局 供需适配 高质量发展 优化建议
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互联网+专科护士区域联动护理在基层老年永久性肠造口早期病人中的应用 被引量:2
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作者 魏苏艳 陈海燕 《护理研究》 北大核心 2024年第3期517-521,共5页
目的:探讨互联网+专科护士区域联动护理在基层老年永久性肠造口早期病人中的应用。方法:选取2019年1月1日—2021年12月31日就诊于某医院胃肠外科行永久性肠造口的70例基层老年病人为研究对象,根据就诊时间将其分为对照组和干预组,对照... 目的:探讨互联网+专科护士区域联动护理在基层老年永久性肠造口早期病人中的应用。方法:选取2019年1月1日—2021年12月31日就诊于某医院胃肠外科行永久性肠造口的70例基层老年病人为研究对象,根据就诊时间将其分为对照组和干预组,对照组给予常规护理,干预组在常规护理的基础上给予互联网+专科护士区域联动护理。采用中文版造口病人社会心理适应量表(OAI-20)和中文版造口病人生活质量量表(Stoma-QOL)分别于病人出院前1 d、出院后1个月、3个月、6个月后评估两组病人社会心理适应和病人生活质量,并比较两组6个月内造口及造口周围皮肤并发症的发生率。结果:70例病人均完成各阶段护理及评估,经重复测量方差分析显示,两组病人在社会心理适应方面和生活质量评估方面存在时间效应、组间效应及交互效应,干预组OAI-20总分、Stoma-QOL总分均高于对照组,差异有统计学意义(P<0.05);6个月内干预组并发症发生率低于对照组(P<0.05)。结论:互联网+专科护士区域联动护理能够提高基层地区老年永久性肠造口病人早期社会及心理适应能力,提高病人生活质量,降低造口并发症发生率,有利于在有限的医疗资源下给予病人同质化的护理。 展开更多
关键词 肠造口 互联网+ 专科护士 区域联动 老年人 适应 生活质量 护理
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严寒地区混合垂直通风猪舍环境质量评价 被引量:1
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作者 王朝元 马晓春 +3 位作者 党昊昱 方志伟 梁超 王钰 《农业工程学报》 EI CAS CSCD 北大核心 2024年第11期204-211,共8页
为探究垂直通风系统(屋顶与粪坑混合排风)在寒区猪舍中的适应性,该研究在秋冬季节对内蒙古某规模化猪舍的热湿与空气质量环境进行了实时连续监测,并根据测试结果对猪舍环境质量进行评价。结果表明:1)测试期间,舍内平均温度、相对湿度以... 为探究垂直通风系统(屋顶与粪坑混合排风)在寒区猪舍中的适应性,该研究在秋冬季节对内蒙古某规模化猪舍的热湿与空气质量环境进行了实时连续监测,并根据测试结果对猪舍环境质量进行评价。结果表明:1)测试期间,舍内平均温度、相对湿度以及氨气(NH_(3))、二氧化碳(CO_(2))、总悬浮颗粒物(total suspended particulate, TSP)浓度分别为22.7℃、59.6%、6.5 mg/m^(3)、2 200 mg/m^(3)、2 915μg/m^(3),舍内通风量为0.34~0.39 m^(3)/(h·kg),各环境指标基本满足生产环境阈值要求;保育期间舍内有效环境温度范围为27.1~30.7℃,存在轻度热应激情况,占总监测时间的12.9%;2)舍内温度、相对湿度与NH_(3)、CO_(2)、TSP浓度空间分布不均匀系数分别为0.01、0.15、0.45、0.03、0.15,各环境参数空间分布均较为均匀;3)试验单元(U1、U3)猪的平均日增质量、料重比与死淘率分别842和818 g/d、2.68和2.79、1.68%和1.31%,生产性能良好。综上,不设吊顶的侧墙进风,屋顶与粪坑混合排风的垂直通风系统,总体上能够满足严寒地区猪舍秋冬季热湿环境与空气质量调节需求,保证良好的生产性能。 展开更多
关键词 通风 温度 相对湿度 猪舍 适应性 热湿环境 空气质量
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全景视频基于块的视口自适应传输方案综述
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作者 李俊杰 望育梅 +1 位作者 李志军 刘雨 《计算机应用》 CSCD 北大核心 2024年第2期536-547,共12页
全景视频由于独特的沉浸式、交互式体验受到广泛关注。全景视频传输所需的高带宽、低时延给现有网络传输系统带来了挑战。基于tile(块)的视口自适应传输可以有效缓解全景视频所带来的传输压力,成为当前的主流方案和研究热点。通过分析基... 全景视频由于独特的沉浸式、交互式体验受到广泛关注。全景视频传输所需的高带宽、低时延给现有网络传输系统带来了挑战。基于tile(块)的视口自适应传输可以有效缓解全景视频所带来的传输压力,成为当前的主流方案和研究热点。通过分析基于tile的视口自适应传输方案的研究现状和发展趋势,对该传输方案的两个重要模块,即视口预测与码率分配进行论述,从不同视角归纳总结相关领域的方法。首先,基于全景视频传输框架对相关技术进行阐明;其次,从主、客观两个维度分别介绍评估传输系统性能的用户体验质量的指标;再后,分别从视口预测、码率分配两方面进行归纳,系统梳理经典的研究方法;最后,基于当前研究现状讨论全景视频传输的未来发展趋势。 展开更多
关键词 全景视频 视口自适应传输 视口预测 码率分配 用户体验质量
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