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Numerical Simulations of Pile Supported Protective System Subjected to Ship Impact 被引量:1
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作者 SUN Zhen WANG Junjie 《Transactions of Tianjin University》 EI CAS 2006年第B09期243-247,共5页
The head-on collision process between ship and concrete pile supported protective system is simulated by software LS-DYNA. The influences of pile non-linearity and soil non-linearity on impact force, ship crush depth ... The head-on collision process between ship and concrete pile supported protective system is simulated by software LS-DYNA. The influences of pile non-linearity and soil non-linearity on impact force, ship crush depth and the cap displacement of pile supported protective system are discussed. It's shown that for both severe impact case and non-severe impact case, the non-linearity of pile material influence the impact force history, ship crush depth. The non-linearity of pile material and soil has remarkable influence on the cap displacement especially for severe impact case. These issues should not be ignored in the analysis of pile supported protective system subjected to ship impact. 展开更多
关键词 pile supported protective system numerical simulation ship impact non-linearity soilpile interaction
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Effects of an oasis protective system on aeolian sediment deposition:a case study from Gelintan oasis,southeastern edge of the Tengger Desert,China
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作者 DING Jing XIE Yun-hu +6 位作者 LI Xiao-jia JIANG Hong-tao WANG Ji LIU Xiao-xi WU Xue-qin WANG Yu-hao HAI Chun-xing 《Journal of Mountain Science》 SCIE CSCD 2020年第8期2023-2034,共12页
Desert-oasis ecotones are boundary areas between oases and desert ecosystems.Large efforts to control sediment and stabilize these boundaries depend on understanding sedimentary processes,especially aeolian transport ... Desert-oasis ecotones are boundary areas between oases and desert ecosystems.Large efforts to control sediment and stabilize these boundaries depend on understanding sedimentary processes,especially aeolian transport and deposition.Previous studies on aeolian sediment deposition have focused primarily on a single land surface type or a single engineering approach.Few studies have considered deposition in a multi-layer oasis protective system.A complete oasis protective system consists of an outer bare sand area,a sand barrier zone,a shrub and herbaceous plant zone,and a farmland shelter zone.This study used sedimentary analysis to quantify grain-size characteristics in samples from the four land surfaces under different types of weather conditions in the Gelintan oasis of the Tengger Desert,the fourth largest desert in China.The results showed that aeolian sediment deposition decreased from the outer bare sand area through the oasis protective system and into the interior.The four land surface types showed significant differences in deposition volume(P<0.05).Deposited sediment showed gradual decrease in dominant grain-size from sand to silt,but sediment deposited during dust weather contained a larger coarse-grained fraction.From the outer desert to the inner oasis,transport mechanisms shifted from saltation(sand)to suspension(silt and smaller)in non-dust weather.During dust weather,deposition primarily occurs from near-surface aeolian sand transport with saltation.Sediment sorting decreased from exterior to interior zones of the protective system while skewness and kurtosis showed no significant change(P<0.05).These results can help inform strategies for stabilizing and protecting desert-oasis ecotones in this region and other localities. 展开更多
关键词 Aeolian sediment deposition Desert oasis ecotone Grain size characteristics Oasis protective system Tengger Desert
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Wind and sand control by an oasis protective system: a case from the southeastern edge of the Tengger Desert, China 被引量:2
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作者 XIE Yun-hu DANG Xiao-hong +10 位作者 MENG Zhong-ju JIANG Hong-tao LI Xiao-jia ZHOU Rui-ping ZHOU Dan-dan LIU Xiao-xi DING Jing WU Xue-qin WANG Yu-hao HAI Chun-xing WANG Ji 《Journal of Mountain Science》 SCIE CSCD 2019年第11期2548-2561,共14页
Wind and sand control are important factors in combating desertification and protecting oases.An oasis protective system can provide these benefits,but quantitative research on protection effects has been lacking to d... Wind and sand control are important factors in combating desertification and protecting oases.An oasis protective system can provide these benefits,but quantitative research on protection effects has been lacking to date.This research describes an oasis protective system in the southeastern border of the Tengger Desert.The system consists of a sand barrier belt,a shrub and herbaceous plant belt,and a farmland shelter belt.The system was compared to a bare dunes area as the control zone.The study investigated windproof effect,sediment transport,and erosion through field observations.Results showed that the roughness of the shrub and herbaceous plant belt,farmland shelter belt,and sand barrier belt were increased compared with bare dunes.The shrub and herbaceous plant belt provided the highest windproof effect values for the same wind velocity measurement height,and the windproof effect values for different protective belts were as follows:shrub and herbaceous plant belt>farmland shelter belt>sand barrier belt.The sand barrier belt provided effective wind and sand control at heights from 0 to 50 cm above the ground.The total sediment transport for each protective belt is as follows:bare dunes>sand barrier belt>shrub and herbaceous plant belt>farmland shelter belt.The sediment transport decreased exponentially as the height increased.In the bare dunes and protective systems,the sediment transport is mainly within 30 cm of the ground surface.The wind erosion intensity for this protective system was as follows:bare dunes>sand barrier belt>shrub and herbaceous plant belt>farmland shelter belt.This research offers quantitative evidence for how oasis protective systems can effectively intercept sand and prevent erosion in oases.The results of this study can be applied in similar regions. 展开更多
关键词 OASIS protective system Windproof effect Sediment transport WIND erosion intensity Tengger DESERT DESERTIFICATION
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Effects of PQQ on Protective System in Cucumber Cotyledons under Low Temperature Stress 被引量:1
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作者 Zhao Yongfang Liu Weiqun +2 位作者 Zhu Yunji Wang Yonghua Wang Guanfang 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第2期235-238,共4页
The authors have studied the effects of Pyrroioguinloine quinone (PQQ) on superoxide dismutase (SOD), Ascorbid acid(AsA) peroxidase (AsAPOD), glutathion (GSH) and electrolytic leakage of cotyledon in cucumber seedling... The authors have studied the effects of Pyrroioguinloine quinone (PQQ) on superoxide dismutase (SOD), Ascorbid acid(AsA) peroxidase (AsAPOD), glutathion (GSH) and electrolytic leakage of cotyledon in cucumber seedling under low temperature stress, meanwhile, 8-hydroquinone (8-HQ) and AsA (activeoxiygen scavengers) have been made use of in comparison with PQQ. The results indicate that the activities of SOD, AsAPOD and content of GSH can be increased by PQQ. The relative conductivity of cotyledon in cucumber seedling is decreased for PQQ possesses the ability of cleaning up free redical of oxygen. We came to the conclusion that PQQ can act as a kind of active oxygen scavenger and adjust the metabolism on free radical of oxygen to balance in plants and enhance resistance finally in plants. 展开更多
关键词 pyrroloquinloine quinone (PQQ) protect system low temperatural stress cucumber seedling active oxygen scavenger
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Hydrophobic protective layer with ultra-long carbon chain for high-performance aqueous zinc ion batteries
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作者 Renming Liu Ze Gao +3 位作者 Linglong Hu Daming Yang Ming Feng Dan Luo 《Chinese Chemical Letters》 2026年第2期545-550,共6页
The formation of Zn dendrites and the occurrence of the hydrogen evolution reaction(HER)at Zn anodes represent two major obstacles that significantly impede the widespread commercialization of aqueous Zn-ion batteries... The formation of Zn dendrites and the occurrence of the hydrogen evolution reaction(HER)at Zn anodes represent two major obstacles that significantly impede the widespread commercialization of aqueous Zn-ion batteries.In this work,we propose sorbitan oleate(Span 80)as a novel amphiphilic electrolyte additive for 2 mol/L ZnSO_(4),demonstrating multifunctional performance.The unique ultra-long hydrophobic carbon chains of Span 80 effectively reduce free water molecules at the Zn anode-electrolyte interface,forming a robust hydrophobic interfacial layer that significantly suppresses HER and corrosion reactions.Simultaneously,carbon chains can enhance the desolvation effect of[Zn(H_(2)O)_(6)]^(2+),leading to improve rate performance.Additionally,the hydrophilic sorbitan groups in Span 80 selectively adsorb onto active sites of the Zn anode,promoting uniform Zn^(2+)deposition and suppressing dendrite growth.The optimized Zn||Zn symmetric cell exhibits outstanding cycling stability,sustaining reversible plating/stripping for 570 h at 50 mA/cm^(2) and the Zn||V_(2)O_(5) full cell retains exceptional stability over 2000 cycles at 1 A/g.Our work presents a promising strategy for suppressing interfacial side reactions by constructing a hydrophobic protective layer through the use of ultra-long carbon chain surfactants.This approach offers new insights into enhancing the performance of aqueous Zn-ion batteries. 展开更多
关键词 Aqueous Zn-ion batteries Zn anode ELECTROLYTE Nonionic surfactants Hydrophobic protective layer
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Application and Effectiveness Evaluation of Standardized Protective Care Procedures in Hydrofluoric Acid Operations within Dental Departments
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作者 Fengqun Yong 《Journal of Clinical and Nursing Research》 2026年第1期174-180,共7页
Objective:To evaluate the implementation effectiveness of standardized protective care procedures during hydrofluoric acid procedures in the dental department.Methods:This study was conducted from June 2023 to June 20... Objective:To evaluate the implementation effectiveness of standardized protective care procedures during hydrofluoric acid procedures in the dental department.Methods:This study was conducted from June 2023 to June 2025,selecting 90 patients who underwent hydrofluoric acid-related treatments in the outpatient dental department of this hospital during this period as subjects.Forty-five patients treated between June 2023 and June 2024 received conventional protective care(pre-intervention group),while 45 patients treated between June 2024 and June 2025 underwent the standardized protective care protocol(post-intervention group).Thirteen healthcare personnel participated in both pre-and post-intervention treatment phases.Based on the different nursing models,indicators such as the incidence of adverse events in patients and the exposure rate of healthcare personnel before and after implementation were compared to evaluate the effectiveness of the nursing intervention.Results:The incidence of oral mucosal irritation reactions in patients was lower after implementation,p<0.05.Compared with the pre-implementation period,the incidence of procedure-related adverse events decreased after implementation,p<0.05.There was a significant difference in the occupational exposure rate of healthcare personnel before and after implementation,with a higher rate observed before implementation(p<0.05).Post-implementation,healthcare personnel achieved higher compliance scores for pre-procedure preparation,intra-procedure protection,and post-procedure handling(p<0.05).Patient satisfaction with treatment was lower pre-implementation than post-implementation(p<0.05).Conclusion:Adherence to standardized protective care procedures during hydrofluoric acid operations by dental department staff in outpatient settings standardizes practitioner techniques,effectively prevents oral mucosal irritation in patients,reduces occupational exposure risks for staff,minimizes adverse procedural events,and consequently enhances patient treatment satisfaction.This demonstrates significant practical value. 展开更多
关键词 Standardized protective care procedures Dental department Outpatient clinic Hydrofluoric acid handling
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Protective effect of Guanxinning on antipsychotic-induced cardiac impairment in long-term hospitalized psychiatric patients
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作者 Fu-Gang Luo Hao-Yu Xing +4 位作者 Jun-Jie Wang Wen-Ye Wu Kai-Jie Fang Hai-Dong Song Juan Yan 《World Journal of Psychiatry》 2026年第1期221-232,共12页
BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chin... BACKGROUND Long-term antipsychotic therapy in psychiatric patients carries significant cardiovascular risks,including QT interval prolongation,myocardial injury,and functional impairment.Guanxinning,a traditional Chinese medicine formulation,has demonstrated cardioprotective potential in preclinical studies,but clinical evidence in this population remains limited.AIM To evaluate the cardioprotective effects of Guanxinning against antipsychotic-induced cardiac injury in long-term hospitalized psychiatric patients.METHODS A randomized,double-blind,placebo-controlled trial was conducted with 120 psychiatric inpatients receiving chronic antipsychotic therapy.Participants were allocated to:Intervention group:Conventional antipsychotics+Guanxinning tablets(0.38 g×4 tablets,ter in die);Control group:Conventional antipsychotics+identical placebo;Cardiac assessments at baseline and 12 months included:Electrocardiography(corrected QT interval),echocardiography(left ventricular ejection fraction,left ventricular end-diastolic diameter),serum biomarkers(cardiac troponin I,B-type natriuretic peptide,superoxide dismutase,malondialdehyde,high-sensitivity C-reactive protein).RESULTS Compared to controls,the Guanxinning group showed:Electrophysiological improvement:Corrected QT shortening(438±25 milliseconds vs 465±30 milliseconds,P<0.01).Functional enhancement:Left ventricular ejection fraction increase(58.5%±5.2%vs 53.8%±4.8%,P<0.05),left ventricular end-diastolic diameter reduction(49.8±3.5 mm vs 52.6±3.8 mm,P<0.05),Biochemical modulation:Reduced myocardial injury markers(cardiac troponin I:0.009 ng/mL vs 0.014 ng/mL;B-type natriuretic peptide:52 pg/mL vs 78 pg/mL,P<0.001),improved oxidative stress(superoxide dismutase:↑13.3 U/mL;malondialdehyde:↓0.9 nmol/mL,P<0.001),attenuated inflammation(high-sensitivity C-reactive protein:2.0 mg/L vs 3.2 mg/L,P<0.001).CONCLUSION Guanxinning significantly mitigates antipsychotic-induced cardiac injury in psychiatric patients,demonstrating:Normalization of electrophysiological parameters,Preservation of systolic/diastolic function,suppression of oxidative stress and inflammation.These findings support its clinical application as an adjunctive cardioprotective therapy,potentially through inhibition of myocardial apoptosis and antioxidant upregulation. 展开更多
关键词 GUANXINNING Antipsychotic drugs Cardiac function SCHIZOPHRENIA Cardiac protection
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Hypervelocity impact response and protection for the track steels of rocket sled system via light-gas gun experiments
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作者 Siwei Zhao Yi Zeng +5 位作者 Xuewen Zhou Weixing Zhao Botao Xie Jianbin Jing Yan Chen Yilun Liu 《Defence Technology(防务技术)》 2026年第2期282-293,共12页
Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud... Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms. 展开更多
关键词 Hypervelocity rocket sled Gouge of the track steels Two-stage light-gas gun Microstructural characterization Coating protection
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Effect of TYLCV Infection on Leaf Anatomical Structure and Protective Enzyme System of Tomato 被引量:7
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作者 张永平 张辉 +1 位作者 朱龙英 朱为民 《Agricultural Science & Technology》 CAS 2009年第4期150-153,共4页
[Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and h... [Objective] The aim was to study the effect of tomato yellow leaf curl virus (TYLCV) infection on leaf anatomical structure and protective enzyme system of tomato. [Method] The anatomical structure of infected and healthy leaves of tomato were observed and compared by using paraffin section method. The activity changes of SOD, POD and CAT in the infected leaves of tomato were determined. [ Result] The results revealed that there were some differences in anatomical structure between healthy and infected leaves. Some cells of infected leaves were damaged so that the leaves curled and became yellow, which affected the normal function of organs. Compared with control, enzyme activities in the tomato plants infected by TYLCV were enhanced at the early periods and higher than that in control, then started to decline at the middle and late periods but lower than that in control.[ Conclusion] After infection by TYLCV, the leaf anatomical structure of tomato was changed greatly and the protective enzyme system was damaged severely, and affected the normal physJological metabolic functions of tissues and organs in tomato in further. 展开更多
关键词 TYLCV INFECTION Anatomical structure protective enzyme system
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Effects of two kinds of transgenic poplar on protective enzymes system in the midgut of larvae of American white moth 被引量:11
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作者 丁双阳 孟秀芹 李学锋 《Journal of Forestry Research》 SCIE CAS CSCD 2001年第2期119-122,147,共4页
The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-i... The leaves of Bt (Bacillus thuringiensis) transgenic poplar (Populus nigra L.) and CpTI (Cowpea trypsin inhibitor) transgenic poplar ((P. tomentosa×P. bolleana)×P. Tomentosa) were taken to feed the 4th-5th-instar larvae of American white moth (Hyphantria cunea (Drury)) for determination of the activities of the protective enzyme system inside larvae’s body. The physiological and biochemical effects of the transgenic poplars on the larvae were studied. The results showed that the two kinds of transgenic poplars had similar effects on the protective enzyme system in the midgut of larvae. The activities of superoxide dismutase, catalase, and peroxidase in midgut of the larvae increased gradually, reached the highest value at a certain time, and then decreased suddenly. For the larvae that were fed with the leaves of Bt transgenic poplar, the peak value of superoxide dismutase and catalase presented at the time of 24-h feeding, while the peak of peroxidase took place at the time of 12-h feeding. The activities of these protective enzymes for the larvae that were fed with leaves of CpTI transgenic poplar peaked 12 h later than that of those fed with leaves of Bt transgenic poplar. The comparison of activities of the protective enzymes was also carried out between the larvae with different levels of intoxication. It was found that the activities of protective enzyme of the seriously intoxicant larvae were higher than that of the lightly intoxicant larvae. This difference was more obvious in the group treated with CpTI transgenic poplar. 展开更多
关键词 Transgenic poplar American white moth protective enzyme system
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Topological considerations for reinforced concrete modular protection systems against near-field overpressure generated by close-in detonations
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作者 Sangyoung Han Kukjoo Kim +4 位作者 Hyeon-Jin Kim Jang-Woon Baek Hyun-Do Yun Gyu-Yong Kim Sangwoo Park 《Defence Technology(防务技术)》 2025年第11期112-125,共14页
With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has b... With the increasing demand for secure infrastructure such as hydrogen refueling stations,chemical plants,and energy storage systems,the need for protective structures capable of withstanding close-in detonations has become more critical.Existing design guidelines for protective walls(e.g.,UFC 3-340-02)primarily address mid-and far-field explosions,providing limited insights into near-field effects.Considering the effect of slight slopes(<40°)on reducing maximum reflected overpressure is deemed negligible.This study investigated the effectiveness of a reinforced concrete(RC)modular protection system(MPS)incorpo rating a diagonally tapered wall in attenuating re flected overpressures from closein detonations.Full-scale field experiments using a 51.3 kg TNT charge,representing the explosion energy of a typical hydrogen vessel rupture,demonstrated that a wall with a 7°slope significantly outperformed a vertical wall of equivalent concrete volume in terms of blast resistance.Observed structural responses included cracking,horizontal shear failure,and overturning.Complementary simulations using a validated computational fluid dynamics(CFD)model showed that the tapered wall reduced peak overpressure by 30%-40%compared to an equivalent vertical wall.This result highlights the potential of minor geometric modifications to enhance blast resilience.The tapered design effectively redirects incident blast waves,reducing localized damage while also conserving material,thus preserving modular benefits such as ease of transport and reusability.These findings suggest that diagonally tapered RC-based MPSs can offer a practical and resilient solution for industrial and military applications subject to near-field or sequential blast threats. 展开更多
关键词 Modular protective system protective wall Close-in detonation Near-field overpressure Full-scale explosion test
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The personal protective equipment(PPE)based on individual combat:A systematic review and trend analysis 被引量:4
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作者 Qian-ran Hu Xing-yu Shen +2 位作者 Xin-ming Qian Guang-yan Huang Meng-qi Yuan 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期195-221,共27页
With the development of ordnance technology,the survival and safety of individual combatants in hightech warfare are under serious threat,and the Personal Protective Equipment(PPE),as an important guarantee to reduce ... With the development of ordnance technology,the survival and safety of individual combatants in hightech warfare are under serious threat,and the Personal Protective Equipment(PPE),as an important guarantee to reduce casualties and maintain military combat effectiveness,is widely developed.This paper systematically reviewed various PPE based on individual combat through literature research and comprehensive discussion,and introduced in detail the latest application progress of PPE in terms of material and technology from three aspects:individual integrated protection system,traditional protection equipment,and intelligent protection equipment,respectively,and discussed in depth the functional improvement and optimization status brought by advanced technology for PPE,focusing on the achievements of individual equipment technology application.Finally,the problems and technical bottlenecks in the development of PPE were analyzed and summarized,and the development trend of PPE were pointed out.The results of the review will provide a forward-looking reference for the current development of individual PPE,and are important guidance for the design and technological innovation of advanced equipment based on the future technological battlefield. 展开更多
关键词 Personal protective equipment(PPE) Individual combat Material and structure Equipment application Intelligent devices Wearable technology
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Protection Distance of Surge Protective Devices in Low Voltage Distribution Systems 被引量:1
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作者 张栋 傅正财 +1 位作者 赵刚 孙伟 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第4期477-481,共5页
Protection distance of surge protective devices (SPDs) is an important problem in designing a good location scheme of SPDs in low voltage distribution systems for protecting electrical equipments against over- voltage... Protection distance of surge protective devices (SPDs) is an important problem in designing a good location scheme of SPDs in low voltage distribution systems for protecting electrical equipments against over- voltage caused by lightning stroke. The simplified lumped-parameter circuit model and the circuit method were used to study the protection distance problem of SPDs. The analytical solutions of the load voltage and general equations of the protection distance of SPDs under different load conditions were given. Simulation results of examples proved the validity of the proposed analytical method. 展开更多
关键词 over-voltage protection surge protective devices (SPDs) effective protection distance lumped-parameter circuit
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A Protective Mechanism for the Access Control System in the Virtual Domain 被引量:1
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作者 Jinan Shen Deqing Zou +3 位作者 Hai Jin Kai Yang Bin Yuan Weiming Li 《China Communications》 SCIE CSCD 2016年第11期129-142,共14页
In traditional framework,mandatory access control(MAC) system and malicious software are run in kernel mode. Malicious software can stop MAC systems to be started and make it do invalid. This problem cannot be solved ... In traditional framework,mandatory access control(MAC) system and malicious software are run in kernel mode. Malicious software can stop MAC systems to be started and make it do invalid. This problem cannot be solved under the traditional framework if the operating system(OS) is comprised since malwares are running in ring 0 level. In this paper,we propose a novel way to use hypervisors to protect kernel integrity and the access control system in commodity operating systems. We separate the access control system into three parts: policy management(PM),security server(SS) and policy enforcement(PE). Policy management and the security server reside in the security domain to protect them against malware and the isolation feather of the hypervisor can protect them from attacks. We add an access vector cache(AVC) between SS and PE in the vip OS,in order to speed up communication between the vip OS and the security domain. The policy enforcement module is retained in the vip OS for performance. The security of AVC and PE can be ensured by using a memory protection mechanism. The goal of protecting the OS kernel is to ensure the security of the execution path. We implementthe system by a modified Xen hypervisor. The result shows that we can secure the security of the access control system in the vip OS with no overhead compared with modules in the latter. Our system offers a centralized security policy for virtual domains in virtual machine environments.Keywords: hypervisor; virtualization; memo- 展开更多
关键词 HYPERVISOR VIRTUALIZATION memory protection vip OS access control system
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Mapping Psychosocial Risk and Protective Factors in Suicidal Older Persons—A Systematic Review 被引量:1
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作者 Anne Lise Holm Elisabeth Severinsson 《Open Journal of Nursing》 2015年第3期260-275,共16页
Social disconnectedness in combination with depression, somatic disease, stigma, social exclusion and functional impairment has been described as a major risk factor for suicide in old age. However, protective factors... Social disconnectedness in combination with depression, somatic disease, stigma, social exclusion and functional impairment has been described as a major risk factor for suicide in old age. However, protective factors have not been focused on in the same way. The aim was to identify psychosocial risk and protective factors in suicidal older persons. A systematic review was performed in Academic Search Premier (34), Ovid Medline (0), PsycInfo (0), PubMed (66), CINAHL (3) and ProQuest (1078) for the period May - September, 2014. Results: Twelve studies were included in the final analysis. Psychosocial risk factors were categorized under four themes: Being a burden to others increases depression and hopelessness, the struggle due to poor social integration, the strain of physical illness and old age and Negative aspects of religious activity. A total of four protective factors emerged: a sense of belonging, maintaining social dignity, satisfaction with relationships and feeling useful and positive aspects of religious activity. In conclusion, the context of a suicidal older person in a home healthcare service may create a “vulnerable psychosocial state” in which she/he is confronted by stressful psychosocial life events including physical illness and social network changes. The fact that protective factors are solely related to social factors needs to be taken into account in future prevention studies. 展开更多
关键词 OLDER protective FACTORS PSYCHOSOCIAL RISK FACTORS SUICIDE
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Numerical Estimation of the Thermal Response of Thermal Protective Clothing-Air Gap-Human Skin Micro-system 被引量:1
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作者 田明伟 王祯 +5 位作者 刘康炜 胡馨之 朱士凤 曲丽君 陈韶娟 周泉 《Journal of Donghua University(English Edition)》 EI CAS 2016年第4期569-573,共5页
Thermal protective clothing has been recognized as the primary shielding against emergency fire hazard and inflammable gas leakage. Therefore,the thermal response of human covered with thermal protective clothing unde... Thermal protective clothing has been recognized as the primary shielding against emergency fire hazard and inflammable gas leakage. Therefore,the thermal response of human covered with thermal protective clothing under high temperature is the key work to investigate the thermal insulation of thermal protective clothing. A coupling model composed of thermal protective clothing,air gap and human skin is established and the temperature of the micro-system is numerically solved via the finite element method( FEM).Especially,the heat transfer of air gap located between clothing and human skin considering conduction and radiation is established while the human skin layers involve the effect of blood perfusion. Then the effect of thermophysical properties( thermal conductivity and volumetric capacity) of fabric and thickness of fabric and air on the thermal response of the micro-system is elucidated and compared.The results indicate that the volumetric heat capacity of fabric is the key parameter to affect the thermal shielding performance of thermal protective clothing,and the thicker fabric thickness and air gap thickness can improve the thermal protective properties of the micro-system. 展开更多
关键词 clothing fabric protective volumetric shielding perfusion insulation conduction elucidated Skin
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An efficient fusion protein system for expression of Bacillus anthracis protective antigen as immunogenic and diagnostic antigen
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作者 Vahid Bagheri Hossein Motamedi Masoud Reza Seifiabad Shapouri 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2010年第10期765-768,共4页
Objective:To produce high quantities of recombinant protective antigen(rPA) for human vaccine and diagnosis.Methods:The PA gene was amplified by PCR with pXO1 plasmid as template. The PCR product was cloned into pMAL-... Objective:To produce high quantities of recombinant protective antigen(rPA) for human vaccine and diagnosis.Methods:The PA gene was amplified by PCR with pXO1 plasmid as template. The PCR product was cloned into pMAL-c2X vector using the BamH1 and SalI restriction enzymes.The recombinant plasmid was transformed into Escherichia coli DH5 a strain and then screened for transformation.The expression of protective antigen was analyzed by SDS-PAGE and Western blotting after isopropyl β-D-thiogalactopyranoside(IPTG) induction.Results: The full-length PA gene(2.2 kb) was cloned into pMAL vector system.The recombinant vector was confirmed by restriction enzyme and PCR analysis.The expression of cytoplasmic maltose-binding protein-protective(MBP-P) antigen fusion protein was detected by SDS-PAGE and Western blotting,and obtained a 125 kDa protein band,which was similar to expected size of fusion protein.Conclusions:This expression system can be used in the high production of rPA. After purification and immunization studies,the purified rPA may be used in the development of the human recombinant anthrax vaccine and also in diagnosis of anthrax disease. 展开更多
关键词 BACILLUS ANTHRACIS Fusion protein protective ANTIGEN VACCINE
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Introduction to Enhanced Protective Film Systems
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作者 LIU Chunlin DAVID Palermo +2 位作者 LI Guoqiang SUN Jianyun CHEN Suwen 《Transactions of Tianjin University》 EI CAS 2008年第B10期491-494,共4页
An explosive blast mitigation alternative has increased the safety of structures by using " catcher" systems. These systems " catch" or repel the failure of the window or in-fill wall pro-tecting l... An explosive blast mitigation alternative has increased the safety of structures by using " catcher" systems. These systems " catch" or repel the failure of the window or in-fill wall pro-tecting life and property from ballistic shards or fragments. They can be designed to be stand-alone in new construction and structural retrofits or used to augment structural hardening tech-niques. Cables, fabrics, and thin gauge sheet steel are examples of catcher systems used in the past. A new and evolving category of catcher systems are based on polymeric materials that can be used for both wall and window upgrades. These products are a proven blast mitigation concept and K&C Protective Technologies Pte Ltd (KCPT) together with Sherwin-Williams(SW) use KCPT′s blast engineering capacity and SW′s material engineering principles to create engineered systems for even greater in-use performance. 展开更多
关键词 explosion blast mitigation catcher system protective film systems
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Influences of 500 kV Transmission Lines on Wetland Ecosystem and Its Protective Countermeasures--A Case Study of the Lake Wetland Natural Reserve along the Yangtze River in Anqing City
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作者 Xia Shangguang Zhao Yuan 《Meteorological and Environmental Research》 CAS 2016年第4期17-22,共6页
The impact of 500 kV transmission lines of Anqing power plant across the lake wetland reserve along the Yangtze River on the safety of the ecosystem was taken as the researched object.The power frequency electric fiel... The impact of 500 kV transmission lines of Anqing power plant across the lake wetland reserve along the Yangtze River on the safety of the ecosystem was taken as the researched object.The power frequency electric field intensity(PFEFI),power frequency magnetic field intensity(PFMFI),radio interference,construction noise,vegetation destruction and the influence on water quality were investigated and monitored,and the influences of PFEFI,PFMFI,radio interference and construction noise on wild animals,especially the habitats and migration of birds were mainly researched.The direct and indirect influences on the surrounding environment as well as plants and animals in sensitive areas were analyzed and predicted.The results firstly showed there existed a 182 400m^3 stereo-space(PFEFI>4kV/m)which made flying birds unsafe under the lowest height 11 mof the lines,which fills the gap in the research of this field.Finally,some operational protection countermeasures were put forward at the current technical level to achieve the win-win goal of economic development and natural protection. 展开更多
关键词 Ultra-high-voltage transmission line Electromagnetic pollution LAKE WETLAND ECOsystem safety protective measures China
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The Mental Protection System for Protective Behaviors: The Social Brain and the Mental Immune System
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作者 Dingyu Chung 《Journal of Behavioral and Brain Science》 2018年第1期31-55,共25页
The physical protection system of the body consists of the protective organs for vulnerable body parts-functions and the protective countermeasures against invaders (pathogens), but to survive, the body also requires ... The physical protection system of the body consists of the protective organs for vulnerable body parts-functions and the protective countermeasures against invaders (pathogens), but to survive, the body also requires the protective social groups for vulnerable social members-functions and the protective instinctive mental countermeasures against adversities such as hardship, danger, and unfamiliarity-uncertainty. As a result, this paper proposes that the mental protection system of the body consists of the social brain to set up the protective social groups for vulnerable social members-functions and the mental immune system to produce the protective mental countermeasures against adversities. This paper proposes that from the social brain, the protective social groups include alliance group for vulnerable individuals, kinship-friendship group for vulnerable children, interdependent specialists group for vulnerable pregnant females, territorial group for social boundary, connective group for social connection, and competitive group for social competition. From the mental immune system, the mental protective countermeasures include comforter against hardship, hyperactivity against danger, phobia against unfamiliarity-uncertainty, and rationality against unfamiliarity-uncertainty. The overactive mental immune system causes mental allergies and auto immune diseases as personality-mental disorders against ubiquitous harmful and harmless perceived adversities, correlating to physical allergies and auto immune diseases against ubiquitous harmful and harmless detected invaders. The mental protection system also produces personality traits, social moralities, social organizations, social systems, religions, and cultures as described in this paper. The mental protective system is the source of protective behaviors. 展开更多
关键词 MENTAL Protection system SOCIAL Brain MENTAL Immune system Big Five PERSONALITY TRAITS SOCIAL system TRAITS PERSONALITY Disorders Psychotherapy Religions Western Culture Eastern Culture protective BEHAVIORS
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