In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated ...In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated that the average numbers of gene copies of Legionella spp. and Mycobacterium spp. were significantly higher than those of Aeromonas spp.(p < 0.05). Legionella spp. and Mycobacterium spp. were 100%(44/44) positively detected while P. aeruginosa and Aeromonas spp. were 79.54%(35/44) and 77.27%(34/44) positively detected. Legionella pneumophila was only detected in 4 samples(4/44), demonstrating its occasional occurrence. No Mycobacterium avium or Naegleria fowleri was detected in any of the samples. The average gene copy numbers of target OPPPs were the highest in summer,suggesting seasonal prevalence of OPPPs. Average gene copy numbers of OPPPs in the taps of low-use-frequency were higher than in taps of high-use-frequency, but the difference was not significant for some OPPPs(p > 0.05). Moderate negative correlations between the chlorine concentration and the gene copy numbers of OPPPs were observed by Spearman analysis(rsranged from -0.311 to -0.710, p < 0.05). However, no significant correlations existed between OPPPs and AOC, BDOC, or turbidity. Moderate positive correlations were observed between the target microorganisms, especially for Acanthamoeba spp., through Spearman analysis(p < 0.05). Based on our studies, it is proposed that disinfectant concentration, season, taps with different-use frequency, OPPP species, and potential microbial correlations should be considered for control of OPPPs in tap water.展开更多
To alleviate the conservativeness of the stability criterion for Takagi-Sugeno （T-S） fuzzy time-delay systems, a new delay-dependent stability criterion was proposed by introducing a new augmented Lyapunov function ...To alleviate the conservativeness of the stability criterion for Takagi-Sugeno （T-S） fuzzy time-delay systems, a new delay-dependent stability criterion was proposed by introducing a new augmented Lyapunov function with an additional triple-integral term, which was firstly u3ed to derive the stability criterion for T-S fuzzy time-delay systems. By the same approach, the robust stability issue for fuzzy time-delay systems with uncertain parameters was also considered. On the other hand, in order to enhance the design flexibility, a new design approach for uncertain fuzzy time-delay systems under imperfect premise matching was also proposed, which allows the fuzzy controller to employ different membership functions from the fuzzy time-delay model. By the numerical examples, the proposed stability conditions are less conservative in the sense of getting larger allowable time-delay and obtaining smaller feedback control gains. For instance, when the allowable time-delay increases from 7.3 s to 12 s for an uncertain T-S fuzzy control system with time-delay, the norm of the feedback gains decreases from （34.299 2, 38.560 3） to （10.073 3, 11.349 0）, respectively. Meanwhile, the effectiveness of the proposed design method was illustrated by the last example with the robustly stable curves of system state under the initial condition of x（0） = [3 -1].展开更多
Process equipment placing in industrial premises leads to essential change of room acoustic characteristics: mean length of sound rays’ free runs, reverberation time and mean absorption factor in a room. The changes ...Process equipment placing in industrial premises leads to essential change of room acoustic characteristics: mean length of sound rays’ free runs, reverberation time and mean absorption factor in a room. The changes influence distribution of the reflected sound energy in premise volume. Failure to take account of the given circumstance results in errors at definition of sound pressure levels and an estimation of efficiency of building-acoustic measures of noise abatement. In the paper the results of computer modeling of acoustic processes in premises with the process equipment are considered and influence of the equipment on a sound absorption indoors is analyzed. The computer simulation is carried out on the basis of the ray tracing method with taking into account rays’ energy distribution in a room. It is shown that such approach allows determining objectively the integral acoustic characteristics of industrial premises, takes into account influencing to them the room parameters, the presence and scattering characteristics of the equipment and makes more accurate the equations putting into engineering practice.展开更多
The issue of the stability and controller design of Takagi-Sugeno（T-S） fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller ...The issue of the stability and controller design of Takagi-Sugeno（T-S） fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller do not share the same membership functions.A new stability criterion which contains the information of membership functions is derived.The new stability criterion is less conservative,and enhances the design flexibility.Two numerical examples are presented to illustrate the conservativeness and effectiveness of the proposed method.展开更多
This study explains how infrastructure and beef processing practices in beef retailing premises (BRPs) are useful for beef purchasing decision. In this respect, features and beef retailing practices were assessed agai...This study explains how infrastructure and beef processing practices in beef retailing premises (BRPs) are useful for beef purchasing decision. In this respect, features and beef retailing practices were assessed against the questionability of beef that is retailed in least developing countries (LDCs). This assessment was carried out by testing the null hypothesis that hypothesizes that BRPs in Dar es Salaam and Mbeya cities do not comply with the FAO technical requirements. The retailed beef in many BRPs is compromised with the status of the infrastructural development, the situation that may result in the questionability of the consumed beef. The Likert based information regarding 22 beef quality impacting factors (BQIF) from BRPs in Dar es Salaam and Mbeya, respectively, was analyzed with respect to the gaps identified and beef retailing conceptual model. This study is important as it provides general picture in connection to the status of the assessed BQIF in BRPs for the cities in the least developing countries (LDCs). In this regard, the study has shown that the compliance of BRPs in the LDCs’ cities is too weak to meet the infrastructural technical requirements due to existence of more stringent provisions in the developed specifications. The study finally identified the local infrastructural beef quality determinants in LDCs’ BRPs as the gap to be bridged by other studies.展开更多
The lack of descriptions regarding the order of precedence between the local laws of cities with subordinate districts and the regulations of provincial governments in Legislation Law of the People's Republic of C...The lack of descriptions regarding the order of precedence between the local laws of cities with subordinate districts and the regulations of provincial governments in Legislation Law of the People's Republic of China(Legislation Law) has led to two divergent views. One holds that "the local laws of cities with subordinate districts should take precedence over the regulations of provincial governments," while the other supports the exact opposite. This is a value judgment issue in legislation. To reach a solution, we need to clarify the premises based on the characteristics of the laws in question so that a basic common ground can be established for discussion. The first premise for traditional legislation is that a law should be based on experience as well as logic; the second is that the experience of authority subjects, plus the three aspects of logic should outweigh the experience of social subjects, plus the three aspects of logic. With respect to postmodern legislation, the first premise is that experience should override logic, and the second is that the experience of the authority subject should take precedence over that of social subject, with no requirements for logical consistency. Since Legislation Law fal s into the category of postmodern legislation, according to the premises, the argument that the local laws of cities with subordinate districts should take precedence enjoys wider acceptance, but the view is logically challenged in terms of conceptual consistency, system consistency and principle consistency. More studies must be conducted to facilitate the discussion.展开更多
基金supported by the National Key Research and Development Plan(No.2016YFA0203200)the National Natural Science Foundation of China(No.51538013)the project of Chinese Academy of Sciences(No.QYZDY-SSW-DQC004)
文摘In this study, qPCR was used to quantify opportunistic premise plumbing pathogens(OPPPs) and free-living amoebae in 11 tap water samples collected over four seasons from a city in northern China. Results demonstrated that the average numbers of gene copies of Legionella spp. and Mycobacterium spp. were significantly higher than those of Aeromonas spp.(p < 0.05). Legionella spp. and Mycobacterium spp. were 100%(44/44) positively detected while P. aeruginosa and Aeromonas spp. were 79.54%(35/44) and 77.27%(34/44) positively detected. Legionella pneumophila was only detected in 4 samples(4/44), demonstrating its occasional occurrence. No Mycobacterium avium or Naegleria fowleri was detected in any of the samples. The average gene copy numbers of target OPPPs were the highest in summer,suggesting seasonal prevalence of OPPPs. Average gene copy numbers of OPPPs in the taps of low-use-frequency were higher than in taps of high-use-frequency, but the difference was not significant for some OPPPs(p > 0.05). Moderate negative correlations between the chlorine concentration and the gene copy numbers of OPPPs were observed by Spearman analysis(rsranged from -0.311 to -0.710, p < 0.05). However, no significant correlations existed between OPPPs and AOC, BDOC, or turbidity. Moderate positive correlations were observed between the target microorganisms, especially for Acanthamoeba spp., through Spearman analysis(p < 0.05). Based on our studies, it is proposed that disinfectant concentration, season, taps with different-use frequency, OPPP species, and potential microbial correlations should be considered for control of OPPPs in tap water.
基金Project(61273095)supported by the National Natural Science Foundation of ChinaProject(135225)supported by the Academy of Finland
文摘To alleviate the conservativeness of the stability criterion for Takagi-Sugeno （T-S） fuzzy time-delay systems, a new delay-dependent stability criterion was proposed by introducing a new augmented Lyapunov function with an additional triple-integral term, which was firstly u3ed to derive the stability criterion for T-S fuzzy time-delay systems. By the same approach, the robust stability issue for fuzzy time-delay systems with uncertain parameters was also considered. On the other hand, in order to enhance the design flexibility, a new design approach for uncertain fuzzy time-delay systems under imperfect premise matching was also proposed, which allows the fuzzy controller to employ different membership functions from the fuzzy time-delay model. By the numerical examples, the proposed stability conditions are less conservative in the sense of getting larger allowable time-delay and obtaining smaller feedback control gains. For instance, when the allowable time-delay increases from 7.3 s to 12 s for an uncertain T-S fuzzy control system with time-delay, the norm of the feedback gains decreases from （34.299 2, 38.560 3） to （10.073 3, 11.349 0）, respectively. Meanwhile, the effectiveness of the proposed design method was illustrated by the last example with the robustly stable curves of system state under the initial condition of x（0） = [3 -1].
文摘Process equipment placing in industrial premises leads to essential change of room acoustic characteristics: mean length of sound rays’ free runs, reverberation time and mean absorption factor in a room. The changes influence distribution of the reflected sound energy in premise volume. Failure to take account of the given circumstance results in errors at definition of sound pressure levels and an estimation of efficiency of building-acoustic measures of noise abatement. In the paper the results of computer modeling of acoustic processes in premises with the process equipment are considered and influence of the equipment on a sound absorption indoors is analyzed. The computer simulation is carried out on the basis of the ray tracing method with taking into account rays’ energy distribution in a room. It is shown that such approach allows determining objectively the integral acoustic characteristics of industrial premises, takes into account influencing to them the room parameters, the presence and scattering characteristics of the equipment and makes more accurate the equations putting into engineering practice.
基金Supported by the National Natural Science Foundation of China(60874084)the Academy of Finland(135225,127299)
文摘The issue of the stability and controller design of Takagi-Sugeno（T-S） fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller do not share the same membership functions.A new stability criterion which contains the information of membership functions is derived.The new stability criterion is less conservative,and enhances the design flexibility.Two numerical examples are presented to illustrate the conservativeness and effectiveness of the proposed method.
文摘This study explains how infrastructure and beef processing practices in beef retailing premises (BRPs) are useful for beef purchasing decision. In this respect, features and beef retailing practices were assessed against the questionability of beef that is retailed in least developing countries (LDCs). This assessment was carried out by testing the null hypothesis that hypothesizes that BRPs in Dar es Salaam and Mbeya cities do not comply with the FAO technical requirements. The retailed beef in many BRPs is compromised with the status of the infrastructural development, the situation that may result in the questionability of the consumed beef. The Likert based information regarding 22 beef quality impacting factors (BQIF) from BRPs in Dar es Salaam and Mbeya, respectively, was analyzed with respect to the gaps identified and beef retailing conceptual model. This study is important as it provides general picture in connection to the status of the assessed BQIF in BRPs for the cities in the least developing countries (LDCs). In this regard, the study has shown that the compliance of BRPs in the LDCs’ cities is too weak to meet the infrastructural technical requirements due to existence of more stringent provisions in the developed specifications. The study finally identified the local infrastructural beef quality determinants in LDCs’ BRPs as the gap to be bridged by other studies.
基金part of the results(presented in stages)of"Research on the Legislative System of Cities with Subordinate Districts"(16XFX004)-a program of National Social Sciences Fund in Western China"Empirical Research on Local Legislation"(16XW16)-a research focus of Sichuan Academy of Social Sciences under a key program launched by the Publicity Department of the CPC Sichuan Provincial Committee
文摘The lack of descriptions regarding the order of precedence between the local laws of cities with subordinate districts and the regulations of provincial governments in Legislation Law of the People's Republic of China(Legislation Law) has led to two divergent views. One holds that "the local laws of cities with subordinate districts should take precedence over the regulations of provincial governments," while the other supports the exact opposite. This is a value judgment issue in legislation. To reach a solution, we need to clarify the premises based on the characteristics of the laws in question so that a basic common ground can be established for discussion. The first premise for traditional legislation is that a law should be based on experience as well as logic; the second is that the experience of authority subjects, plus the three aspects of logic should outweigh the experience of social subjects, plus the three aspects of logic. With respect to postmodern legislation, the first premise is that experience should override logic, and the second is that the experience of the authority subject should take precedence over that of social subject, with no requirements for logical consistency. Since Legislation Law fal s into the category of postmodern legislation, according to the premises, the argument that the local laws of cities with subordinate districts should take precedence enjoys wider acceptance, but the view is logically challenged in terms of conceptual consistency, system consistency and principle consistency. More studies must be conducted to facilitate the discussion.
