In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t...In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals.展开更多
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ...This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal.展开更多
There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas incre...There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas increases,which will lead to fouling,erosion and plugging of downstream equipment. In this study,the main effects of SO_3 on the safety,stability and efficiency of units were analyzed,and measures to control SO_3 were proposed.展开更多
Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture wh...Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.展开更多
In this paper we mainly consider little Hankel operators with squareintegrable symbols on the weighted Bergman spaces of the unit ball.We obtain that Schatten class of little Hankel operators is equivalent to Schatten...In this paper we mainly consider little Hankel operators with squareintegrable symbols on the weighted Bergman spaces of the unit ball.We obtain that Schatten class of little Hankel operators is equivalent to Schatten class of positive Toeplitz operators under the conditions that SMO(f) ∈ L p/2 (B n,dλ) and 2 ≤ p ∞,which is very important to research the relation between Toeplitz operators and little Hankel operators.展开更多
In this paper, we define β-Hausdorff operator on the unit polydisk and study the boundedness of the operator on Lipschitz space. Firstly, we translate the problem of coefficient into integral of weighted composition ...In this paper, we define β-Hausdorff operator on the unit polydisk and study the boundedness of the operator on Lipschitz space. Firstly, we translate the problem of coefficient into integral of weighted composition operator, then give the sufficient conditions of boundedness, and also obtain an upper bound for the operator norm on Lipschitz space.展开更多
Background: Pain is the common experience among post operative patients admitted to the intensive care unit. Inadequate management can lead to undesired complications which can increase risk for morbidity and mortalit...Background: Pain is the common experience among post operative patients admitted to the intensive care unit. Inadequate management can lead to undesired complications which can increase risk for morbidity and mortality. Objective: The aim of this study was to assess pain management and factors associated with its severity among post surgical patients admitted in intensive care unit at MNH. Method: A prospective study was conducted from October 2017 to February 2018 involving a total of 123 post operative patients aged 18 years and above admitted to the surgical and obstetric intensive care units. Structured questionnaires were used to obtain the required perioperative information. Severity of pain was assessed by using the Numerical Rating Scale (NRS). Data was analyzed using SPSS version 23.0. Frequency, percentages, tables and charts were used to summarize the study findings. Bivariate analysis and multivariate logistic regression were done. P-value of Results: The prevalence of severe post operative pain within 24 and 72 hours was 32.1% and 41.5% respectively. Pre operative use of analgesia (OR: 2.66, CI: 1.15 - 6.12, P value = 0.02), abdominal surgery (OR: 4.12 CI: 1.12 - 15.88, P value = 0.03) and thoracic surgeries (OR;7.42, CI: 1.54 - 35.88, P value = 0.01) was significantly associated with severe pain. Age, sex, ASA class, duration of surgery, and level of education did not show significant association with pain severity. Opioids prescribed postoperatively were pethidine (70.7%), morphine (11.4%) and fentanyl (11.4%). Other analgesics used were paracetamol (60.2%) and diclofenac (22%). Conclusion: The magnitude of post operative pain was high. Pre operative uses of analgesia, abdominal and thoracic surgery were the factors associated with severe pain. Pethidine and paracetamol were the most prescribed drugs, however the prescription pattern used was inadequate to control pain.展开更多
The anomaly detection of the brake operating unit (BOU) in thebrake systems on metro vehicle is critical for the safety and reliability ofthe trains. On the other hand, current periodic inspection and maintenanceare u...The anomaly detection of the brake operating unit (BOU) in thebrake systems on metro vehicle is critical for the safety and reliability ofthe trains. On the other hand, current periodic inspection and maintenanceare unable to detect anomalies in an early stage. Also, building an accurateand stable system for detecting anomalies is extremely difficult. Therefore,we present an efficient model that use an ensemble of recurrent autoencodersto accurately detect the BOU abnormalities of metro trains. This is the firstproposal to employ an ensemble deep learning technique to detect BOUabnormalities in metro train braking systems. One of the anomalous caseson metro vehicles is the case when the air cylinder (AC) pressures are less thanthe brake cylinder (BC) pressures in certain parts where the brake pressuresincrease before coming to a halt. Hence, in this work, we first extract the dataof BC and AC pressures. Then, the extracted data of BC and AC pressuresare divided into multiple subsequences that are used as an input for bothbi-directional long short-term memory (biLSTM) and bi-directional gatedrecurrent unit (biGRU) autoencoders. The biLSTM and biGRU autoencodersare trained using training dataset that only contains normal subsequences. Fordetecting abnormalities from test dataset which consists of abnormal subsequences, the mean absolute errors (MAEs) between original subsequences andreconstructed subsequences from both biLSTM and biGRU autoencoders arecalculated. As an ensemble step, the total error is calculated by averaging twoMAEs from biLSTM and biGRU autoencoders. The subsequence with totalerror greater than a pre-defined threshold value is considered an abnormality.We carried out the experiments using the BOU dataset on metro vehiclesin South Korea. Experimental results demonstrate that the ensemble modelshows better performance than other autoencoder-based models, which showsthe effectiveness of our ensemble model for detecting BOU anomalies onmetro trains.展开更多
Mycoflora of atmospheric air and dust samples collected from air conditioning systems in 12 of each I.C.U. (intensive care units) and O.R. (operation rooms) were tested using settle and dilution plate methods on f...Mycoflora of atmospheric air and dust samples collected from air conditioning systems in 12 of each I.C.U. (intensive care units) and O.R. (operation rooms) were tested using settle and dilution plate methods on four types of agar media and incubated at 25℃. Forty-five fungal species representing 23 genera were isolated and identified. The most prevalent genera recorded were Cladosporium, Aspergillus, Penicillium and Fusarium. The total colony forming units of airborne fungi recovered in I.C.U. and O.R. ranged between 31.13-49.61 colonies/m3 on the four types of media usedl The fungal total catch of the dust samples collected from the air conditioning system filters in I.C.U. and O.R. were ranged from 65.5-170 colonies/mg dust. Since, the interest to replace synthetic xenobiotics by natural compounds with low environmental persistence and biodegradable to control such airborne fungal contaminants is needed. In this respect, essential oils showed to possess a broad spectrum of antifungal activity. Fungal static ability of six oils was tested on 30 different fungal isolates. Vapors of common thyme oil exhibited the strongest inhibitory effects on the tested isolates, whereas the headspace vapors of blue gum and ginger had no inhibitory effects on the tested fungal isolates. These data revealed that the air conditioning systems may be an important source of contamination in I.C.U. and O.R. of Assiut university hospitals. Thus, patients may be in risk of being exposed to contaminated atmospheric air by opportunistic fungi and the use of essential oils as an alternative option to control hospital wards from fungal contaminants needs further studies.展开更多
On December 25, 2009, after the 72-hour trail operation, Unit 2 of Laxiwa Hydropower Station on the Yellow River, constructed by CPI Yellow River Hydropower Corporation, was formally
Based on tests and theoretical calculation an optimum steam admission mode is proposed which can effectively solve the steam-excited vibration.An operation mode jointly considering the valve point and operation load i...Based on tests and theoretical calculation an optimum steam admission mode is proposed which can effectively solve the steam-excited vibration.An operation mode jointly considering the valve point and operation load is proposed based on the analysis and study of a large number of unit operation optimization methods.According to the steam-excited vibration that occurs during the optimization process when the nozzle governing steam turbine switches from a single valve to multi-valves a steam admission optimization program is proposed.This comprehensive program considering the steam-excited vibration is applied to a 600 MW steam turbine unit to obtain the optimum sliding pressure curve and the optimum operation mode and the steam-excited vibration is solved successfully.展开更多
Operation optimization is an effective method to explore potential economic benefits for existing plants. The m.aximum potential benefit from operationoptimization is determined by the distances between current operat...Operation optimization is an effective method to explore potential economic benefits for existing plants. The m.aximum potential benefit from operationoptimization is determined by the distances between current operating point and process constraints, which is related to the margins of design variables. Because of various ciisturbances in chemical processes, some distances must be reserved for fluctuations of process variables and the optimum operating point is not on some process constraints. Thus the benefit of steady-state optimization can not be fully achied(ed while that of dynamic optimization can be really achieved. In this study, the steady-state optimizationand dynamic optimization are used, and the potential benefit-is divided into achievable benefit for profit and unachievable benefit for control. The fluid catalytic cracking unit (FCCU) is used for case study. With the analysis on how the margins of design variables influence the economic benefit and control performance, the bottlenecks of process design are found and appropriate control structure can be selected.展开更多
Production planning models generated by common modeling systems do not involve constraints for process operations, and a solution optimized by these models is called a quasi-optimal plan. The quasi-optimal plan cannot...Production planning models generated by common modeling systems do not involve constraints for process operations, and a solution optimized by these models is called a quasi-optimal plan. The quasi-optimal plan cannot be executed in practice some time for no corresponding operating conditions. In order to determine a practi- cally feasible optimal plan and corresponding operating conditions of fluidized catalytic cracking unit (FCCU), a novel close-loop integrated strategy, including determination of a quasi-optimal plan, search of operating conditions of FCCU and revision of the production planning model, was proposed in this article. In the strategy, a generalized genetic algorithm (GA) coupled with a sequential process simulator of FCCU was applied to search operating conditions implementing the quasi-optimal plan of FCCU and output the optimal individual in the GA search as a final genetic individual. When no corresponding operating conditions were found, the final genetic individual based correction (FGIC) method was presented to revise the production planning model, and then a new quasi-optimal production plan was determined. The above steps were repeated until a practically feasible optimal plan and corresponding operating conditions of FCCU were obtained. The close-loop integrated strategy was validated by two cases, and it was indicated that the strategy was efficient in determining a practically executed optimal plan and corresponding operating conditions of FCCU.展开更多
Although the taxonomy of oligotrich ciliates has been widely investigated,yet the species diversity remains poorly known.We newly designed a pair of oligotrich-specific LSU rDNA primers covering the 600-bp D1/D2 regio...Although the taxonomy of oligotrich ciliates has been widely investigated,yet the species diversity remains poorly known.We newly designed a pair of oligotrich-specific LSU rDNA primers covering the 600-bp D1/D2 region,and it was effective for detecting oligotrich species.Using the primers,we constructed the cloning libraries to investigate the species diversity of oligotrichs in the northern coastal waters of the South China Sea.In total,165 oligotrich sequences were obtained from five widely separated sampling sites.Sixty operational taxonomic units(OTUs)were obtained at 99%similarity threshold,and low-abundance OTUs with no more than two sequences contributed most of these(about 78%).Our findings are consistent with previous morphological studies,Strombidium was found the most abundant and widely distributed genus in this area.In addition,the BLAST search in the NCBI database resulted in 95%OTUs matching with named oligotrich species in similarity below 99%.Therefore,oligotrich morphospecies diversity has been underestimated as low-abundance species,and the LSU rDNA oligotrich sequence database needs to be better promoted.展开更多
基金supported by the Natural Science Foundation of Hunan Province of China(2022JJ30369)the Education Department Important Foundation of Hunan Province in China(23A0095)。
文摘In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals.
基金Supported by the National Natural Science Foundation of China (10771064)the Natural Science Foundation of Zhejiang province (Y6090036+1 种基金Y7080197,Y606197)the Foundation of Department of Education of Zhejiang Province (20070482)
文摘This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal.
基金Supported by National High Technology Research and Development Program of China(863 Program)(2013AA065401)
文摘There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas increases,which will lead to fouling,erosion and plugging of downstream equipment. In this study,the main effects of SO_3 on the safety,stability and efficiency of units were analyzed,and measures to control SO_3 were proposed.
文摘Coal preparation is an integral part of the coal commodity supply chain. This stage of post-mining, pre-utilization beneficiation uses low-cost separation technologies to remove unwanted mineral matter and moisture which hinder the value of the coal product. Coal preparation plants typically employ several parallel circuits of cleaning and dewatering operations, with each circuit designed to optimally treat a specific size range of coal. Recent innovations in coal preparation have increased the efficiency and capac- ity of individual unit operations while reinforcing the standard parallel cleaning approach. This article, which describes the historical influences and state-of-the-art design for the various coal preparation unit operations, is organized to distinguish between coarse/intermediate coal cleaning and fine/ultrafine coal cleaning. Size reduction, screening, classification, cleaning, dewatering, waste disposal unit operations are particularly highlighted, with a special focus on the LI.S. design philosophy. Notable differences between the U.S. and international operations are described as appropriate.
文摘In this paper we mainly consider little Hankel operators with squareintegrable symbols on the weighted Bergman spaces of the unit ball.We obtain that Schatten class of little Hankel operators is equivalent to Schatten class of positive Toeplitz operators under the conditions that SMO(f) ∈ L p/2 (B n,dλ) and 2 ≤ p ∞,which is very important to research the relation between Toeplitz operators and little Hankel operators.
文摘In this paper, we define β-Hausdorff operator on the unit polydisk and study the boundedness of the operator on Lipschitz space. Firstly, we translate the problem of coefficient into integral of weighted composition operator, then give the sufficient conditions of boundedness, and also obtain an upper bound for the operator norm on Lipschitz space.
文摘Background: Pain is the common experience among post operative patients admitted to the intensive care unit. Inadequate management can lead to undesired complications which can increase risk for morbidity and mortality. Objective: The aim of this study was to assess pain management and factors associated with its severity among post surgical patients admitted in intensive care unit at MNH. Method: A prospective study was conducted from October 2017 to February 2018 involving a total of 123 post operative patients aged 18 years and above admitted to the surgical and obstetric intensive care units. Structured questionnaires were used to obtain the required perioperative information. Severity of pain was assessed by using the Numerical Rating Scale (NRS). Data was analyzed using SPSS version 23.0. Frequency, percentages, tables and charts were used to summarize the study findings. Bivariate analysis and multivariate logistic regression were done. P-value of Results: The prevalence of severe post operative pain within 24 and 72 hours was 32.1% and 41.5% respectively. Pre operative use of analgesia (OR: 2.66, CI: 1.15 - 6.12, P value = 0.02), abdominal surgery (OR: 4.12 CI: 1.12 - 15.88, P value = 0.03) and thoracic surgeries (OR;7.42, CI: 1.54 - 35.88, P value = 0.01) was significantly associated with severe pain. Age, sex, ASA class, duration of surgery, and level of education did not show significant association with pain severity. Opioids prescribed postoperatively were pethidine (70.7%), morphine (11.4%) and fentanyl (11.4%). Other analgesics used were paracetamol (60.2%) and diclofenac (22%). Conclusion: The magnitude of post operative pain was high. Pre operative uses of analgesia, abdominal and thoracic surgery were the factors associated with severe pain. Pethidine and paracetamol were the most prescribed drugs, however the prescription pattern used was inadequate to control pain.
基金This research is supported by the Korea Agency for Infrastructure Technology Advancement(KAIA)grant funded by the Ministry of Land,Infrastructure and Transport(Grant21QPWO-B152223-03).
文摘The anomaly detection of the brake operating unit (BOU) in thebrake systems on metro vehicle is critical for the safety and reliability ofthe trains. On the other hand, current periodic inspection and maintenanceare unable to detect anomalies in an early stage. Also, building an accurateand stable system for detecting anomalies is extremely difficult. Therefore,we present an efficient model that use an ensemble of recurrent autoencodersto accurately detect the BOU abnormalities of metro trains. This is the firstproposal to employ an ensemble deep learning technique to detect BOUabnormalities in metro train braking systems. One of the anomalous caseson metro vehicles is the case when the air cylinder (AC) pressures are less thanthe brake cylinder (BC) pressures in certain parts where the brake pressuresincrease before coming to a halt. Hence, in this work, we first extract the dataof BC and AC pressures. Then, the extracted data of BC and AC pressuresare divided into multiple subsequences that are used as an input for bothbi-directional long short-term memory (biLSTM) and bi-directional gatedrecurrent unit (biGRU) autoencoders. The biLSTM and biGRU autoencodersare trained using training dataset that only contains normal subsequences. Fordetecting abnormalities from test dataset which consists of abnormal subsequences, the mean absolute errors (MAEs) between original subsequences andreconstructed subsequences from both biLSTM and biGRU autoencoders arecalculated. As an ensemble step, the total error is calculated by averaging twoMAEs from biLSTM and biGRU autoencoders. The subsequence with totalerror greater than a pre-defined threshold value is considered an abnormality.We carried out the experiments using the BOU dataset on metro vehiclesin South Korea. Experimental results demonstrate that the ensemble modelshows better performance than other autoencoder-based models, which showsthe effectiveness of our ensemble model for detecting BOU anomalies onmetro trains.
文摘Mycoflora of atmospheric air and dust samples collected from air conditioning systems in 12 of each I.C.U. (intensive care units) and O.R. (operation rooms) were tested using settle and dilution plate methods on four types of agar media and incubated at 25℃. Forty-five fungal species representing 23 genera were isolated and identified. The most prevalent genera recorded were Cladosporium, Aspergillus, Penicillium and Fusarium. The total colony forming units of airborne fungi recovered in I.C.U. and O.R. ranged between 31.13-49.61 colonies/m3 on the four types of media usedl The fungal total catch of the dust samples collected from the air conditioning system filters in I.C.U. and O.R. were ranged from 65.5-170 colonies/mg dust. Since, the interest to replace synthetic xenobiotics by natural compounds with low environmental persistence and biodegradable to control such airborne fungal contaminants is needed. In this respect, essential oils showed to possess a broad spectrum of antifungal activity. Fungal static ability of six oils was tested on 30 different fungal isolates. Vapors of common thyme oil exhibited the strongest inhibitory effects on the tested isolates, whereas the headspace vapors of blue gum and ginger had no inhibitory effects on the tested fungal isolates. These data revealed that the air conditioning systems may be an important source of contamination in I.C.U. and O.R. of Assiut university hospitals. Thus, patients may be in risk of being exposed to contaminated atmospheric air by opportunistic fungi and the use of essential oils as an alternative option to control hospital wards from fungal contaminants needs further studies.
文摘On December 25, 2009, after the 72-hour trail operation, Unit 2 of Laxiwa Hydropower Station on the Yellow River, constructed by CPI Yellow River Hydropower Corporation, was formally
基金The National Natural Science Foundation of China(No.51176031)
文摘Based on tests and theoretical calculation an optimum steam admission mode is proposed which can effectively solve the steam-excited vibration.An operation mode jointly considering the valve point and operation load is proposed based on the analysis and study of a large number of unit operation optimization methods.According to the steam-excited vibration that occurs during the optimization process when the nozzle governing steam turbine switches from a single valve to multi-valves a steam admission optimization program is proposed.This comprehensive program considering the steam-excited vibration is applied to a 600 MW steam turbine unit to obtain the optimum sliding pressure curve and the optimum operation mode and the steam-excited vibration is solved successfully.
基金Supported by the National Natural Science Foundation of China(21006127)the National Basic Research Program of China(2012CB720500)the Science Foundation of China University of Petroleum(KYJJ2012-05-28)
文摘Operation optimization is an effective method to explore potential economic benefits for existing plants. The m.aximum potential benefit from operationoptimization is determined by the distances between current operating point and process constraints, which is related to the margins of design variables. Because of various ciisturbances in chemical processes, some distances must be reserved for fluctuations of process variables and the optimum operating point is not on some process constraints. Thus the benefit of steady-state optimization can not be fully achied(ed while that of dynamic optimization can be really achieved. In this study, the steady-state optimizationand dynamic optimization are used, and the potential benefit-is divided into achievable benefit for profit and unachievable benefit for control. The fluid catalytic cracking unit (FCCU) is used for case study. With the analysis on how the margins of design variables influence the economic benefit and control performance, the bottlenecks of process design are found and appropriate control structure can be selected.
文摘Production planning models generated by common modeling systems do not involve constraints for process operations, and a solution optimized by these models is called a quasi-optimal plan. The quasi-optimal plan cannot be executed in practice some time for no corresponding operating conditions. In order to determine a practi- cally feasible optimal plan and corresponding operating conditions of fluidized catalytic cracking unit (FCCU), a novel close-loop integrated strategy, including determination of a quasi-optimal plan, search of operating conditions of FCCU and revision of the production planning model, was proposed in this article. In the strategy, a generalized genetic algorithm (GA) coupled with a sequential process simulator of FCCU was applied to search operating conditions implementing the quasi-optimal plan of FCCU and output the optimal individual in the GA search as a final genetic individual. When no corresponding operating conditions were found, the final genetic individual based correction (FGIC) method was presented to revise the production planning model, and then a new quasi-optimal production plan was determined. The above steps were repeated until a practically feasible optimal plan and corresponding operating conditions of FCCU were obtained. The close-loop integrated strategy was validated by two cases, and it was indicated that the strategy was efficient in determining a practically executed optimal plan and corresponding operating conditions of FCCU.
基金Supported by the National Natural Science Foundation of China(Nos.31772440,31430077,41576124,31761133001)the Pearl River Science and Technology Nova Program of Guangzhou(No.201610010162) to YZ+1 种基金Guangdong MEPP Fund(No.GDOE(2019)A23)the Special Support Program of Guangdong Province to YZ
文摘Although the taxonomy of oligotrich ciliates has been widely investigated,yet the species diversity remains poorly known.We newly designed a pair of oligotrich-specific LSU rDNA primers covering the 600-bp D1/D2 region,and it was effective for detecting oligotrich species.Using the primers,we constructed the cloning libraries to investigate the species diversity of oligotrichs in the northern coastal waters of the South China Sea.In total,165 oligotrich sequences were obtained from five widely separated sampling sites.Sixty operational taxonomic units(OTUs)were obtained at 99%similarity threshold,and low-abundance OTUs with no more than two sequences contributed most of these(about 78%).Our findings are consistent with previous morphological studies,Strombidium was found the most abundant and widely distributed genus in this area.In addition,the BLAST search in the NCBI database resulted in 95%OTUs matching with named oligotrich species in similarity below 99%.Therefore,oligotrich morphospecies diversity has been underestimated as low-abundance species,and the LSU rDNA oligotrich sequence database needs to be better promoted.