In recent days,the tent manufacturers in ZhenJiang,JiangSu and TianJin have made all-out efforts to produce the relief tents,which are in urgent need of refugees in quake-hit areas,to show their human’s love to refug...In recent days,the tent manufacturers in ZhenJiang,JiangSu and TianJin have made all-out efforts to produce the relief tents,which are in urgent need of refugees in quake-hit areas,to show their human’s love to refugees in quake-hit area by their actual actions.展开更多
Background:The German Military Medical Service contributed to the medical screening of unaccompanied minor refugees(UMRs)coming to Germany in 2014 and 2015.In this study,a broad range of diagnostic procedures was appl...Background:The German Military Medical Service contributed to the medical screening of unaccompanied minor refugees(UMRs)coming to Germany in 2014 and 2015.In this study,a broad range of diagnostic procedures was applied to identify microorganisms with clinical or public health significance.Previously,those tests had only been used to screen soldiers returning from tropical deployments.This instance is the first time the approach has been studied in a humanitarian context.Methods:The offered screenings included blood cell counts,hepatitis B serology and microscopy of the stool to look for protozoa and worm eggs as well as PCR from stool samples targeting pathogenic bacteria,protozoa and helminths.If individuals refused certain assessments,their decision to do so was accepted.A total of 219 apparently healthy male UMRs coming from Afghanistan,Egypt,Somalia,Eritrea,Syria,Ghana,Guinea,Iran,Algeria,Iraq,Benin,Gambia,Libya,Morocco,Pakistan,and Palestine were assessed.All UMRs who were examined at the study department were included in the assessment.Results:We detected decreasing frequencies of pathogens that included diarrhoea-associated bacteria[Campylobacter(C.)jejuni,enteropathogenic Escherichia(E.)coli(EPEC),enterotoxic E.coli(ETEC),enteroaggregative E.coli(EAEC),enteroinvasive E.coli(EIEC)/Shigella spp.),Giardia(G.)duodenalis,helminths(comprising Schistosoma spp.,Hymenolepis(H.)nana,Strongyloides(S.)stercoralis]as well as hepatitis B virus.Pathogenic microorganisms dominated the samples by far.While G.duodenalis was detected in 11.4%of the assessed UMRs,the incidence of newly identified cases in the German population was 4.5 cases per 100,000 inhabitants.Conclusion:We conclude that the applied in-house PCR screening systems,which have proven to be useful for screening military returnees from tropical deployments,can also be used for health assessment of immigrants from the respective sites.Apparently healthy UMRs may be enterically colonized with a broad variety of pathogenic and apathogenic microorganisms.Increased colonization rates,as shown for G.duodenalis,can pose a hygiene problem in centralized homes for asylum seekers.展开更多
In this paper,a discrete predator-prey model with prey refuge is investigated.It is proved that the model undergoes codimension-2 bifurcations associated with 1:2 and 1:3 resonances.The bifurcation diagrams and phase ...In this paper,a discrete predator-prey model with prey refuge is investigated.It is proved that the model undergoes codimension-2 bifurcations associated with 1:2 and 1:3 resonances.The bifurcation diagrams and phase portraits show that the model has some interesting complex dynamical behaviors,such as limit cycle,periodic solutions,chaos and codimension-1 bifurcations.展开更多
A stiffened cylindrical shell is normally used in refuge chambers of a coal mine. Based on the method of application and shape characteristics of a refuge chamber, we simplified its shell as an orthotropic cylinder. T...A stiffened cylindrical shell is normally used in refuge chambers of a coal mine. Based on the method of application and shape characteristics of a refuge chamber, we simplified its shell as an orthotropic cylinder. The basic buckling equation of the stiffened cylindrical shell under uniform axial compression was deduced by using a Donnell function. The factors affecting its buckling capacity were studied by theoretical analysis and numerical calculations. The results reveal that the torsional rigidity of the longitudinal stiffener had little effect on the buckling capacity of the shell and that the critical load of an externally stiffened cylindrical shell is higher than that of an internally stiffened cylindrical shell.展开更多
In order to preferably identify infrared image of refuge chamber, reduce image noises of refuge chamber and retain more image details, we propose the method of combining two-dimensional discrete wavelet transform and ...In order to preferably identify infrared image of refuge chamber, reduce image noises of refuge chamber and retain more image details, we propose the method of combining two-dimensional discrete wavelet transform and bilateral denoising. First, the wavelet transform is adopted to decompose the image of refuge chamber, of which low frequency component remains unchanged. Then, three high-frequency components are treated by bilateral filtering, and the image is reconstructed. The result shows that the combination of bilateral filtering and wavelet transform for image denoising can better retain the details which are included in the image, while providing better visual effect. This is superior to using either bilateral filtering or wavelet transform alone. It is useful for perfecting emergency refuge system of coal mines.展开更多
The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for ...The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for personnel in refuge chamber is limited. Thus, how to effectively use the compressed air and oxygen and try to improve the time of supply has a great significance. Supplying more oxygen will result in waste, while supplying less oxygen will cause its concentration to be lower, and harm life safety. This research uses the theoretical calculation and numerical simulation, finds critical gas supply for refuge chamber, and illuminates the change law of gas concentration with critical gas supply in refuge chamber,which provides theoretical guidance for effective use of compressed air and oxygen in refuge chamber.展开更多
Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal mines.One of the biggest concerns with occupied RAs is the possible severity of the r...Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal mines.One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment.In 30 CFR 7.504,the maximum allowable apparent temperature(AT)for an occupied RA is specified as 35℃(95°F).Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35℃(95°F)AT limit.For these tests,heat input devices are used to input the metabolic heat of actual miners.A wide variety of test methods,sensors,and heat input devices could be used when conducting such tests.Since 2012,the National Institute for Occupational Safety and Health(NIOSH)has conducted over thirty 96-hour heat/humidity tests on four different RAs.This paper discusses the test equipment and procedures used during these investigations.This information is useful for RA manufacturers conducting RA heat/humidity tests,for other researchers investigating RA heat/humidity buildup,and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.展开更多
Background: Research indicates that Posttraumatic stress disorder(PTSD) has an extensive impact on family relationships. Nevertheless, there is a dearth of empirically supported interventions addressing family functio...Background: Research indicates that Posttraumatic stress disorder(PTSD) has an extensive impact on family relationships. Nevertheless, there is a dearth of empirically supported interventions addressing family functioning and PTSD. In the Netherlands, it is considered good clinical practice to offer multi-family therapy(MFT) to veteran and refugee families. MFT for traumatized families aims to address the dysfunctional family patterns that have evolved to address the consequences with trauma.Methods: The aim of this study is to generate a common framework for the practical impact and active ingredients of MFT in families confronted with trauma. The Delphi method was used to study the expert opinion of 11 therapists in Dutch expert trauma institutes.Results: The results indicate that MFT is a promising treatment for families dealing with the consequences of trauma. According to experts, positive outcomes include an increased understanding between family members,particularly visible in the de-escalation of conflicts within the family, and improved parenting. One explanation for the effectiveness of MFT with these target groups is its defining feature of therapy with several families.Conclusions: The findings support the importance of considering family relationships and the family context in interventions for traumatized individuals.展开更多
Influences of prey refuge on the dynamics of a predator-prey model with ratio-dependent functional response are investigated. The local and global stability of positive equilibrium of the system are considered. Theore...Influences of prey refuge on the dynamics of a predator-prey model with ratio-dependent functional response are investigated. The local and global stability of positive equilibrium of the system are considered. Theoretical analysis indicates that constant refuge leads to the system undergo supercritical Hopf bifurcation twice with the birth rate of prey species changing continuously.展开更多
In order to reduce the risk of sealing and improve the structural strength for a coal mine mobile refuge chamber,a new type of one-piece model was designed.Mechanical and mathematical calculation performed an importan...In order to reduce the risk of sealing and improve the structural strength for a coal mine mobile refuge chamber,a new type of one-piece model was designed.Mechanical and mathematical calculation performed an important role.Calculated according to statics and relevant contents,the structure had the same total volume as the traditional segmented structure,but had shorter length,wider width and greater height.Those prevented the structure from stress or deformation failure.Some reinforcing ribs with enough moments of inertia were welded in the external shell.Because of the one-piece structure,this refuge chamber reduced the risk of sealing which was a serious problem of segmented structure.Impact load with 300 ms duration and0.6 MPa over-pressure was settled.Explicit nonlinear dynamic analysis program was used to simulate the response of the refuge chamber.The maximum stress and the maximum displacement were obtained.The refuge chamber including blast airtight doors could meet the rigidity requirement.Weak parts of the chamber were the front and back end shell where bigger displacement values occurred than others.Thus,the calculation indicated that the refuge chamber could meet structural safety requirements.Based on the numerical analysis,suggestions were put forward for further resistance ability improvement.Only large inclined shaft with larger wellhead was suitable for this one-piece coal mine mobile refuge chamber.展开更多
In order to investigate detonation propagation and distribution problems of premixed CH_4 ＋ 2O_2 mixture around a concrete structure such as a refuge chamber,detonation experiments in one small size tube were conduct...In order to investigate detonation propagation and distribution problems of premixed CH_4 ＋ 2O_2 mixture around a concrete structure such as a refuge chamber,detonation experiments in one small size tube were conducted. A simulation method was developed to obtain the flow field load distribution in the coal mine lane and pressure load of each part for the refuge chamber. Firstly,a physical model of a full-size explosiontest lane was established,which included the refuge chamber. With the calculations of the exact initial detonation pressure,the propagation characteristics of CH_4 ＋ 2O_2 premixed mixture detonation in the lane was simulated. Simulation results of various parts from AUTODYN are recorded,and the shock wave arrival time and the pressure peak can be observed from the detonation pressure-time curve over the changing propagation distance. So curve differences in different locations cannot be ignored. Then by detonation experiments in the small size tube,detonation pressure-time curves and velocity were obtained. Finally the simulation waveform of variation curve agreed well with the experimental results,which validated the detonation simulation method. The difference between shockwaves of the two sensors confirmed that detonation wave changed along with distance and time. These results should be taken into serious consideration for the detonation progration and distribution problem in future researches.展开更多
文摘In recent days,the tent manufacturers in ZhenJiang,JiangSu and TianJin have made all-out efforts to produce the relief tents,which are in urgent need of refugees in quake-hit areas,to show their human’s love to refugees in quake-hit area by their actual actions.
文摘Background:The German Military Medical Service contributed to the medical screening of unaccompanied minor refugees(UMRs)coming to Germany in 2014 and 2015.In this study,a broad range of diagnostic procedures was applied to identify microorganisms with clinical or public health significance.Previously,those tests had only been used to screen soldiers returning from tropical deployments.This instance is the first time the approach has been studied in a humanitarian context.Methods:The offered screenings included blood cell counts,hepatitis B serology and microscopy of the stool to look for protozoa and worm eggs as well as PCR from stool samples targeting pathogenic bacteria,protozoa and helminths.If individuals refused certain assessments,their decision to do so was accepted.A total of 219 apparently healthy male UMRs coming from Afghanistan,Egypt,Somalia,Eritrea,Syria,Ghana,Guinea,Iran,Algeria,Iraq,Benin,Gambia,Libya,Morocco,Pakistan,and Palestine were assessed.All UMRs who were examined at the study department were included in the assessment.Results:We detected decreasing frequencies of pathogens that included diarrhoea-associated bacteria[Campylobacter(C.)jejuni,enteropathogenic Escherichia(E.)coli(EPEC),enterotoxic E.coli(ETEC),enteroaggregative E.coli(EAEC),enteroinvasive E.coli(EIEC)/Shigella spp.),Giardia(G.)duodenalis,helminths(comprising Schistosoma spp.,Hymenolepis(H.)nana,Strongyloides(S.)stercoralis]as well as hepatitis B virus.Pathogenic microorganisms dominated the samples by far.While G.duodenalis was detected in 11.4%of the assessed UMRs,the incidence of newly identified cases in the German population was 4.5 cases per 100,000 inhabitants.Conclusion:We conclude that the applied in-house PCR screening systems,which have proven to be useful for screening military returnees from tropical deployments,can also be used for health assessment of immigrants from the respective sites.Apparently healthy UMRs may be enterically colonized with a broad variety of pathogenic and apathogenic microorganisms.Increased colonization rates,as shown for G.duodenalis,can pose a hygiene problem in centralized homes for asylum seekers.
基金Supported by the National Natural Science Foundation of China(Grant No.12271421)The Shaanxi Province Innovation Talent Promotion Plan Project(Grant No.2023KJXX-056).
文摘In this paper,a discrete predator-prey model with prey refuge is investigated.It is proved that the model undergoes codimension-2 bifurcations associated with 1:2 and 1:3 resonances.The bifurcation diagrams and phase portraits show that the model has some interesting complex dynamical behaviors,such as limit cycle,periodic solutions,chaos and codimension-1 bifurcations.
基金Financial support from the National Hi-tech Research and Development Program of China is much appreciated
文摘A stiffened cylindrical shell is normally used in refuge chambers of a coal mine. Based on the method of application and shape characteristics of a refuge chamber, we simplified its shell as an orthotropic cylinder. The basic buckling equation of the stiffened cylindrical shell under uniform axial compression was deduced by using a Donnell function. The factors affecting its buckling capacity were studied by theoretical analysis and numerical calculations. The results reveal that the torsional rigidity of the longitudinal stiffener had little effect on the buckling capacity of the shell and that the critical load of an externally stiffened cylindrical shell is higher than that of an internally stiffened cylindrical shell.
基金the Scientific Research Project of Zhejiang Education Department of China (No. Y20108569)the Soft Science Project of Ningbo of China (No. 2011A1058)the Soft Science of Zhejiang Association for Science and Technology of China (No. KX12E-10)
文摘In order to preferably identify infrared image of refuge chamber, reduce image noises of refuge chamber and retain more image details, we propose the method of combining two-dimensional discrete wavelet transform and bilateral denoising. First, the wavelet transform is adopted to decompose the image of refuge chamber, of which low frequency component remains unchanged. Then, three high-frequency components are treated by bilateral filtering, and the image is reconstructed. The result shows that the combination of bilateral filtering and wavelet transform for image denoising can better retain the details which are included in the image, while providing better visual effect. This is superior to using either bilateral filtering or wavelet transform alone. It is useful for perfecting emergency refuge system of coal mines.
基金supported by the National Natural Science Foundation of China(Grant Nos.51504251,51404263)the National Natural Science Foundation of Jiangsu of China(Nos.BK20140187,BK20130203)+4 种基金the Fundamental Research Funds for the Central Universities(2015QNB01)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Central Universities Special Funds for Fundamental Research Funds of the China University of Mining and Technology(No.2014ZDPY04)the Innovation Team of CUMT(2014QN001)the Natural Science Foundation of Jiangsu Province(No.BK2012571)
文摘The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for personnel in refuge chamber is limited. Thus, how to effectively use the compressed air and oxygen and try to improve the time of supply has a great significance. Supplying more oxygen will result in waste, while supplying less oxygen will cause its concentration to be lower, and harm life safety. This research uses the theoretical calculation and numerical simulation, finds critical gas supply for refuge chamber, and illuminates the change law of gas concentration with critical gas supply in refuge chamber,which provides theoretical guidance for effective use of compressed air and oxygen in refuge chamber.
文摘Since 2009,the Mine Safety and Health Administration(MSHA)has required mines to install refuge alternatives(RAs)in underground coal mines.One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment.In 30 CFR 7.504,the maximum allowable apparent temperature(AT)for an occupied RA is specified as 35℃(95°F).Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35℃(95°F)AT limit.For these tests,heat input devices are used to input the metabolic heat of actual miners.A wide variety of test methods,sensors,and heat input devices could be used when conducting such tests.Since 2012,the National Institute for Occupational Safety and Health(NIOSH)has conducted over thirty 96-hour heat/humidity tests on four different RAs.This paper discusses the test equipment and procedures used during these investigations.This information is useful for RA manufacturers conducting RA heat/humidity tests,for other researchers investigating RA heat/humidity buildup,and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.
基金supported in part by a grant from de Bond van Nederlands Militaire Oorlogs-en dienstslachtoffers(BNMO)
文摘Background: Research indicates that Posttraumatic stress disorder(PTSD) has an extensive impact on family relationships. Nevertheless, there is a dearth of empirically supported interventions addressing family functioning and PTSD. In the Netherlands, it is considered good clinical practice to offer multi-family therapy(MFT) to veteran and refugee families. MFT for traumatized families aims to address the dysfunctional family patterns that have evolved to address the consequences with trauma.Methods: The aim of this study is to generate a common framework for the practical impact and active ingredients of MFT in families confronted with trauma. The Delphi method was used to study the expert opinion of 11 therapists in Dutch expert trauma institutes.Results: The results indicate that MFT is a promising treatment for families dealing with the consequences of trauma. According to experts, positive outcomes include an increased understanding between family members,particularly visible in the de-escalation of conflicts within the family, and improved parenting. One explanation for the effectiveness of MFT with these target groups is its defining feature of therapy with several families.Conclusions: The findings support the importance of considering family relationships and the family context in interventions for traumatized individuals.
基金Supported by the NNSF of China(11126284)Supported by the NSF of Department of Education of Henan Province(12A110012)Supported by the Young Scientific Research Foundation of Henan Normal University(1001)
文摘Influences of prey refuge on the dynamics of a predator-prey model with ratio-dependent functional response are investigated. The local and global stability of positive equilibrium of the system are considered. Theoretical analysis indicates that constant refuge leads to the system undergo supercritical Hopf bifurcation twice with the birth rate of prey species changing continuously.
基金Supported by the Major State Basic Research Development Program of China(973Project)(2011CB706900)
文摘In order to reduce the risk of sealing and improve the structural strength for a coal mine mobile refuge chamber,a new type of one-piece model was designed.Mechanical and mathematical calculation performed an important role.Calculated according to statics and relevant contents,the structure had the same total volume as the traditional segmented structure,but had shorter length,wider width and greater height.Those prevented the structure from stress or deformation failure.Some reinforcing ribs with enough moments of inertia were welded in the external shell.Because of the one-piece structure,this refuge chamber reduced the risk of sealing which was a serious problem of segmented structure.Impact load with 300 ms duration and0.6 MPa over-pressure was settled.Explicit nonlinear dynamic analysis program was used to simulate the response of the refuge chamber.The maximum stress and the maximum displacement were obtained.The refuge chamber including blast airtight doors could meet the rigidity requirement.Weak parts of the chamber were the front and back end shell where bigger displacement values occurred than others.Thus,the calculation indicated that the refuge chamber could meet structural safety requirements.Based on the numerical analysis,suggestions were put forward for further resistance ability improvement.Only large inclined shaft with larger wellhead was suitable for this one-piece coal mine mobile refuge chamber.
基金Supported by the National Science Foundation of China(E041003)the Fundamental Research Funds for the Central Universities(FRF-TP-15-105 A1)the Postdoctoral Science Foundation of China(2015M580049)
文摘In order to investigate detonation propagation and distribution problems of premixed CH_4 ＋ 2O_2 mixture around a concrete structure such as a refuge chamber,detonation experiments in one small size tube were conducted. A simulation method was developed to obtain the flow field load distribution in the coal mine lane and pressure load of each part for the refuge chamber. Firstly,a physical model of a full-size explosiontest lane was established,which included the refuge chamber. With the calculations of the exact initial detonation pressure,the propagation characteristics of CH_4 ＋ 2O_2 premixed mixture detonation in the lane was simulated. Simulation results of various parts from AUTODYN are recorded,and the shock wave arrival time and the pressure peak can be observed from the detonation pressure-time curve over the changing propagation distance. So curve differences in different locations cannot be ignored. Then by detonation experiments in the small size tube,detonation pressure-time curves and velocity were obtained. Finally the simulation waveform of variation curve agreed well with the experimental results,which validated the detonation simulation method. The difference between shockwaves of the two sensors confirmed that detonation wave changed along with distance and time. These results should be taken into serious consideration for the detonation progration and distribution problem in future researches.
