More than ever before, environmental preservation has been a critical issue for the survival of the world’s habitat. An attempt to explore global trends in environmental monitoring using numerous ways based on differ...More than ever before, environmental preservation has been a critical issue for the survival of the world’s habitat. An attempt to explore global trends in environmental monitoring using numerous ways based on different techniques is an exercise in the right direction. This is expedient, given the recent overwhelming growing rate of environmental pollution of advertisement graphical bills worldwide. Posting of advertisement graphical bills constitutes one of the biggest threats to man and his environment as it now appears and as we live in an age of growing sensitivity to environmental cleanliness. Pollution of the Nigerian cities through advertisement bills assumes the general term of outdoor advertising ranging from hand-printed signs, posters, painted bulletins and spectaculars. However this paper discusses the trends of posting graphic advertisement bills in Nigerian cities. Its impact on aesthetics, as well as the pollution problems associated with the urban development. The study areas are Abuja, Akure, Ibadan and Lagos. In order to ensure that each unit of the population is represented, random sampling technique was used to get the necessary information from the samples. The findings emphasize the importance of strict control and market regulations in posting of advertisement bill in built environment and eradication of pollution of the environment.展开更多
Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer...Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.展开更多
In hot arid countries with severe weather, the summer air conditioning systems consume much electrical power at peak period. Shifting the loads peak to off-peak period with thermal storage is recommended. Model A of r...In hot arid countries with severe weather, the summer air conditioning systems consume much electrical power at peak period. Shifting the loads peak to off-peak period with thermal storage is recommended. Model A of residential buildings and Model B of schools and hospitals were used to estimate the daily cooling load profile in Makkah, Saudi Arabia at latitude of 21.42°N and longitude of 39.83°E. Model A was constructed from common materials, but Model B as Model A with 5 - 8 cm thermal insulation and double layers glass windows. The average data of Makkah weather through 2010, 2011 and 2012 were used to calculate the cooling load profile and performance of air conditioning systems. The maximum cooling load was calculated at 15:00 o’clock for a main floor building to a 40-floor of residential building and to 5 floors of schools. A district cooling plant of 180,000 Refrigeration Ton was suggested to serve the Gabal Al Sharashf area in the central zone of Makkah. A thermal storage system to store the excess cooling capacity was used. Air cooled condensers were used in the analysis of chiller refrigeration cycle. The operating cost was mainly a function of electrical energy consumption. Fixed electricity tariff was 0.04 $/kWh for electromechanical counter, and 0.027, 0.04, 0.069 $/kWh for shifting loads peak for the smart digital counter. The results showed that the daily savings in consumed power are 8.27% in spring, 6.86% in summer, 8.81% in autumn, and 14.55% in winter. Also, the daily savings in electricity bills are 12.26% in spring, 16.66% in summer, 12.84% in autumn, and 14.55% in winter. The obtained maximum saving in consumed power is 14.5% and the daily saving in electricity bills is 43% in summer when the loads peak is completely shifted to off-peak period.展开更多
Currency is one of indispensable mechanism for the commercial economy development. As the complexity of the British New England commercial economy growing, the urgent need for a stable value currency as a means of pay...Currency is one of indispensable mechanism for the commercial economy development. As the complexity of the British New England commercial economy growing, the urgent need for a stable value currency as a means of payment of daily trading. But the currency was always a problem restricting the development of commercial economy of New England, which was not only related to the economic management function of colonial government itself, but also a political game between colonies and her mother country government.展开更多
Recently,electric vehicles(EVs)have been widely used under the call of green travel and environmental protection,and diverse requirements for charging are also increasing gradually.In order to ensure the authenticity ...Recently,electric vehicles(EVs)have been widely used under the call of green travel and environmental protection,and diverse requirements for charging are also increasing gradually.In order to ensure the authenticity and privacy of charging information interaction,blockchain technology is proposed and applied in charging station billing systems.However,there are some issues in blockchain itself,including lower computing efficiency of the nodes and higher energy consumption in the consensus process.To handle the above issues,in this paper,combining blockchain and mobile edge computing(MEC),we develop a reliable billing data transmission scheme to improve the computing capacity of nodes and reduce the energy consumption of the consensus process.By jointly optimizing the primary and replica nodes offloading decisions,block size and block interval,the transaction throughput of the blockchain system is maximized,as well as the latency and energy consumption of the system are minimized.Moreover,we formulate the joint optimization problem as a Markov decision process(MDP).To tackle the dynamic and continuity of the system state,the reinforcement learning(RL)is introduced to solve the MDP problem.Finally,simulation results demonstrate that the performance improvement of the proposed scheme through comparison with other existing schemes.展开更多
The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators...The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators）. Existing law regulation is not enough precise regarding definition of methods for metering energy transits （energy interchanged between neighboring TSOs）. This paper analyses disadvantages of method for line losses metering with electric meters and suggests introduction of the measured value corrections.展开更多
Aiming at the shortcomings of the existing electric energy metering method,combining with the harmonic responsibility analysis model based on the reference impedance method and the idea of apparent power decomposition...Aiming at the shortcomings of the existing electric energy metering method,combining with the harmonic responsibility analysis model based on the reference impedance method and the idea of apparent power decomposition in IEEE Std 1459-2010 standard,two new metering indicators—billing active power and billing power factor are defined.A new electric energy metering method is proposed and its specific implementation steps are given.The simulation model is built in Matlab/Simulink,and three different examples are set up.Using the simulation data,the various metering indicators need to be examined by the existing electric energy metering method and the new electric energy metering method are calculated.The calculation results show that the new electric energy metering method not only overcomes the shortcomings of the existing electric energy metering method,but also is very easy to be popularized and applied.展开更多
Web of Things(WoT)resources are not only numerous,but also have a wide range of applications and deployments.The centralized WoT resource sharing mechanism lacks flexibility and scalability,and hence cannot satisfy re...Web of Things(WoT)resources are not only numerous,but also have a wide range of applications and deployments.The centralized WoT resource sharing mechanism lacks flexibility and scalability,and hence cannot satisfy requirement of distributed resource sharing in large-scale environment.In response to this problem,a trusted and secure mechanism for WoT resources sharing based on context and blockchain(CWoT-Share)was proposed.Firstly,the mechanism can respond quickly to the changes of the application environment by dynamically determining resource access control rules according to the context.Then,the flexible resource charging strategies,which reduced the fees paid by the users who shared more resources and increased the fees paid by users who frequently used resources maliciously,were used to fulfill efficient sharing of WoT resources.Meanwhile,the charging strategies also achieve load balancing by dynamic selection of WoT resources.Finally,the open source blockchain platform Ethereum was used for the simulation and the simulation results show that CWoT-Share can flexibly adapt to the application environment and dynamically adjust strategies of resource access control and resource charging.展开更多
In order to adopt Billings Method for fertility regulation during the period of breast feeding, cervical mucus was observed and monitored in 61 breast feeding mothers.Urine estrogen and /or pregnanediol ...In order to adopt Billings Method for fertility regulation during the period of breast feeding, cervical mucus was observed and monitored in 61 breast feeding mothers.Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. Observations on cervical mucus during 244 months were collected. The type of dry or no mucus was observed in 75.27% fully breast feeding mothers. Constant unchanging mucus was observed in 69.39% partially breast feeding mothers. Developmental changing mucus was observed in 79.25% of mothers bottle feeding their infants. According to the record on cervical mucus within 6 months postpartum, 97.14% of the cervical mucus was consistent with normal menstrual cycles. Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. The level of estrogen in urine averaged 0.08 μmol/24 h in fully breast feeding mothers and 0.14 μmol/24 h in partially breast feeding mothers.The peak level averaged 0.21 μmol/24 h in bottle feeding mothers.The pregnanediol level was determined to confirm ovulation in bottle feeding mothers. The average levels of cut off and the period of ovulation in 6 bottle feeding mother were 7 μmol/24 h and 9 μmol/24 h respectively.Measurement of urine estrogen and pregnanediol level all matched with cervical mucus appearances. Conclusion: Billings Method is a simple, scientific method for contraception without side effects during breast feeding period.展开更多
A two dimension unsteady heat transfer model is established for rectangular billet casting. Solidification process of liquid steel in secondary cooling zone was analyzed using direct difference method. The influence o...A two dimension unsteady heat transfer model is established for rectangular billet casting. Solidification process of liquid steel in secondary cooling zone was analyzed using direct difference method. The influence of operation parameters including casting speed and temperature of liquid steel was investigated. Experimental results have been used for increasing the casting speed.展开更多
IP billing is not only a basic functionality to operate IP sen＇ices, but also it is fundamental to offer customers with a stable and QoS-enabled network environment. As IP-based network has been widely agreed to be t...IP billing is not only a basic functionality to operate IP sen＇ices, but also it is fundamental to offer customers with a stable and QoS-enabled network environment. As IP-based network has been widely agreed to be the core network of NGN, and existing IP billing system is too simple to fulfill the emerging requirements, the next generation IP billing has become an interesting topic in recent years. Policy-based management brings flexibility and scalability to systems by describing management logic and functions through policies, and thus reduces the complexity of the management of large-scale systems. Working on existing efforts, this paper proposed an improved IETF policy framework based upon which a policy-based billing management architecture for the next generation IP-based network was presented. Then a prototype with some basic functionalities was developed. The results of the experiment validated the expected improvements specified in this paper.展开更多
Objective The effectiveness and acceptability of Billings Ovulation Method (BOM) during breastfeeding were studied. At the same time, the monitoring indexes of fertility return were studied.Methods It was a clinical c...Objective The effectiveness and acceptability of Billings Ovulation Method (BOM) during breastfeeding were studied. At the same time, the monitoring indexes of fertility return were studied.Methods It was a clinical comparative study of BOM and IUD containing copper (200mm 2). The annual rate of pregnancy, discontinuation rate and continuation rate in the two groups was determined. The serum prolactin and estradiol in 90 breastfeeding mothers and urine estrogen and pregnanediol in different feeding mothers were measured.Results There were 219 subjects in the BOM group and 200 in the IUD group. The pregnancy rate in this two groups was 1. 43% and 1. 54% respectively. The rates of discontinuation and continuation in the IUD group were:8. 87% and 91. 35% as well as in the BOM group were 8. 53% and 90. 17% respectively. Neither result was statistically significant (P>0. 05). The experimtal research showed that menses return was well estimated by 0. 35 ratio of serum prolactin vs. estrodiol. Sensitivity and specificity was 94. 61% and 84. 61% respectively. It also indicated that (1) the levels of urine hormone were closely related to the patterns of cervical mucus and (2) the incidence of ovulating before the second return of menses in partially breastfeeding mothers was much lower than that of bottle-feeding mothers (47. 05% vs. 94. 20%). Conclusion BOM is a simple, reliable and well accepted contraceptive method of during breastfeeding. If it can be combined with the measurement of serum prolactin/ estradiol, the date of menses return will be determined more easily. Encouraging mothers to breast-feed will be beneficial to the health of both babies and mothers and delay the fertility return of mothers.展开更多
文摘More than ever before, environmental preservation has been a critical issue for the survival of the world’s habitat. An attempt to explore global trends in environmental monitoring using numerous ways based on different techniques is an exercise in the right direction. This is expedient, given the recent overwhelming growing rate of environmental pollution of advertisement graphical bills worldwide. Posting of advertisement graphical bills constitutes one of the biggest threats to man and his environment as it now appears and as we live in an age of growing sensitivity to environmental cleanliness. Pollution of the Nigerian cities through advertisement bills assumes the general term of outdoor advertising ranging from hand-printed signs, posters, painted bulletins and spectaculars. However this paper discusses the trends of posting graphic advertisement bills in Nigerian cities. Its impact on aesthetics, as well as the pollution problems associated with the urban development. The study areas are Abuja, Akure, Ibadan and Lagos. In order to ensure that each unit of the population is represented, random sampling technique was used to get the necessary information from the samples. The findings emphasize the importance of strict control and market regulations in posting of advertisement bill in built environment and eradication of pollution of the environment.
基金the National Natural Science Founda-tion of China (No. 70471022)the NSFC / Hong KongResearch Grant Council (No. 70418013)
文摘Customer requirements analysis is the key step for product variety design of mass customiza-tion(MC). Quality function deployment (QFD) is a widely used management technique for understanding the voice of the customer (VOC), however, QFD depends heavily on human subject judgment during extracting customer requirements and determination of the importance weights of customer requirements. QFD pro-cess and related problems are so complicated that it is not easily used. In this paper, based on a general data structure of product family, generic bill of material (GBOM), association rules analysis was introduced to construct the classification mechanism between customer requirements and product architecture. The new method can map customer requirements to the items of product family architecture respectively, accomplish the mapping process from customer domain to physical domain directly, and decrease mutual process between customer and designer, improve the product design quality, and thus furthest satisfy customer needs. Finally, an example of customer requirements mapping of the elevator cabin was used to illustrate the proposed method.
文摘In hot arid countries with severe weather, the summer air conditioning systems consume much electrical power at peak period. Shifting the loads peak to off-peak period with thermal storage is recommended. Model A of residential buildings and Model B of schools and hospitals were used to estimate the daily cooling load profile in Makkah, Saudi Arabia at latitude of 21.42°N and longitude of 39.83°E. Model A was constructed from common materials, but Model B as Model A with 5 - 8 cm thermal insulation and double layers glass windows. The average data of Makkah weather through 2010, 2011 and 2012 were used to calculate the cooling load profile and performance of air conditioning systems. The maximum cooling load was calculated at 15:00 o’clock for a main floor building to a 40-floor of residential building and to 5 floors of schools. A district cooling plant of 180,000 Refrigeration Ton was suggested to serve the Gabal Al Sharashf area in the central zone of Makkah. A thermal storage system to store the excess cooling capacity was used. Air cooled condensers were used in the analysis of chiller refrigeration cycle. The operating cost was mainly a function of electrical energy consumption. Fixed electricity tariff was 0.04 $/kWh for electromechanical counter, and 0.027, 0.04, 0.069 $/kWh for shifting loads peak for the smart digital counter. The results showed that the daily savings in consumed power are 8.27% in spring, 6.86% in summer, 8.81% in autumn, and 14.55% in winter. Also, the daily savings in electricity bills are 12.26% in spring, 16.66% in summer, 12.84% in autumn, and 14.55% in winter. The obtained maximum saving in consumed power is 14.5% and the daily saving in electricity bills is 43% in summer when the loads peak is completely shifted to off-peak period.
文摘Currency is one of indispensable mechanism for the commercial economy development. As the complexity of the British New England commercial economy growing, the urgent need for a stable value currency as a means of payment of daily trading. But the currency was always a problem restricting the development of commercial economy of New England, which was not only related to the economic management function of colonial government itself, but also a political game between colonies and her mother country government.
基金in part by the National Natural Science Foundation of China under Grant 61901011in part by the Foundation of Beijing Municipal Commission of Education under Grant KM202110005021 and KM202010005017.
文摘Recently,electric vehicles(EVs)have been widely used under the call of green travel and environmental protection,and diverse requirements for charging are also increasing gradually.In order to ensure the authenticity and privacy of charging information interaction,blockchain technology is proposed and applied in charging station billing systems.However,there are some issues in blockchain itself,including lower computing efficiency of the nodes and higher energy consumption in the consensus process.To handle the above issues,in this paper,combining blockchain and mobile edge computing(MEC),we develop a reliable billing data transmission scheme to improve the computing capacity of nodes and reduce the energy consumption of the consensus process.By jointly optimizing the primary and replica nodes offloading decisions,block size and block interval,the transaction throughput of the blockchain system is maximized,as well as the latency and energy consumption of the system are minimized.Moreover,we formulate the joint optimization problem as a Markov decision process(MDP).To tackle the dynamic and continuity of the system state,the reinforcement learning(RL)is introduced to solve the MDP problem.Finally,simulation results demonstrate that the performance improvement of the proposed scheme through comparison with other existing schemes.
文摘The quality of methods for determining energy transits on the tie lines （lines that connect two neighboring power system） can have significant impact on business activity of the TSOs （transmission system operators）. Existing law regulation is not enough precise regarding definition of methods for metering energy transits （energy interchanged between neighboring TSOs）. This paper analyses disadvantages of method for line losses metering with electric meters and suggests introduction of the measured value corrections.
基金National Natural Science Foundation of China(No.51367010)Science and Technology Program of Gansu Province(No.17JR5RA083)+1 种基金Program for Excellent Team of Scientific Research of Lanzhou Jiaotong University(No.201701)Scientific Research Program of Colleges and Universities of Gansu Province(No.2016B-032)。
文摘Aiming at the shortcomings of the existing electric energy metering method,combining with the harmonic responsibility analysis model based on the reference impedance method and the idea of apparent power decomposition in IEEE Std 1459-2010 standard,two new metering indicators—billing active power and billing power factor are defined.A new electric energy metering method is proposed and its specific implementation steps are given.The simulation model is built in Matlab/Simulink,and three different examples are set up.Using the simulation data,the various metering indicators need to be examined by the existing electric energy metering method and the new electric energy metering method are calculated.The calculation results show that the new electric energy metering method not only overcomes the shortcomings of the existing electric energy metering method,but also is very easy to be popularized and applied.
基金This study is funded by“The National Natural Science Foundation of China(No.61972211,No.61771258)”.
文摘Web of Things(WoT)resources are not only numerous,but also have a wide range of applications and deployments.The centralized WoT resource sharing mechanism lacks flexibility and scalability,and hence cannot satisfy requirement of distributed resource sharing in large-scale environment.In response to this problem,a trusted and secure mechanism for WoT resources sharing based on context and blockchain(CWoT-Share)was proposed.Firstly,the mechanism can respond quickly to the changes of the application environment by dynamically determining resource access control rules according to the context.Then,the flexible resource charging strategies,which reduced the fees paid by the users who shared more resources and increased the fees paid by users who frequently used resources maliciously,were used to fulfill efficient sharing of WoT resources.Meanwhile,the charging strategies also achieve load balancing by dynamic selection of WoT resources.Finally,the open source blockchain platform Ethereum was used for the simulation and the simulation results show that CWoT-Share can flexibly adapt to the application environment and dynamically adjust strategies of resource access control and resource charging.
文摘In order to adopt Billings Method for fertility regulation during the period of breast feeding, cervical mucus was observed and monitored in 61 breast feeding mothers.Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. Observations on cervical mucus during 244 months were collected. The type of dry or no mucus was observed in 75.27% fully breast feeding mothers. Constant unchanging mucus was observed in 69.39% partially breast feeding mothers. Developmental changing mucus was observed in 79.25% of mothers bottle feeding their infants. According to the record on cervical mucus within 6 months postpartum, 97.14% of the cervical mucus was consistent with normal menstrual cycles. Urine estrogen and /or pregnanediol were/was measured in 15 breast feeding mothers. The level of estrogen in urine averaged 0.08 μmol/24 h in fully breast feeding mothers and 0.14 μmol/24 h in partially breast feeding mothers.The peak level averaged 0.21 μmol/24 h in bottle feeding mothers.The pregnanediol level was determined to confirm ovulation in bottle feeding mothers. The average levels of cut off and the period of ovulation in 6 bottle feeding mother were 7 μmol/24 h and 9 μmol/24 h respectively.Measurement of urine estrogen and pregnanediol level all matched with cervical mucus appearances. Conclusion: Billings Method is a simple, scientific method for contraception without side effects during breast feeding period.
文摘A two dimension unsteady heat transfer model is established for rectangular billet casting. Solidification process of liquid steel in secondary cooling zone was analyzed using direct difference method. The influence of operation parameters including casting speed and temperature of liquid steel was investigated. Experimental results have been used for increasing the casting speed.
基金Supported by the High Technology Reseearch and Development Plogranune of China （No. 2002AA121062） and the National Natural Science Foundation of China （ No. 90204002 ）.
文摘IP billing is not only a basic functionality to operate IP sen＇ices, but also it is fundamental to offer customers with a stable and QoS-enabled network environment. As IP-based network has been widely agreed to be the core network of NGN, and existing IP billing system is too simple to fulfill the emerging requirements, the next generation IP billing has become an interesting topic in recent years. Policy-based management brings flexibility and scalability to systems by describing management logic and functions through policies, and thus reduces the complexity of the management of large-scale systems. Working on existing efforts, this paper proposed an improved IETF policy framework based upon which a policy-based billing management architecture for the next generation IP-based network was presented. Then a prototype with some basic functionalities was developed. The results of the experiment validated the expected improvements specified in this paper.
基金The project was funded by Shanghai Municipal Science & Technology Commission
文摘Objective The effectiveness and acceptability of Billings Ovulation Method (BOM) during breastfeeding were studied. At the same time, the monitoring indexes of fertility return were studied.Methods It was a clinical comparative study of BOM and IUD containing copper (200mm 2). The annual rate of pregnancy, discontinuation rate and continuation rate in the two groups was determined. The serum prolactin and estradiol in 90 breastfeeding mothers and urine estrogen and pregnanediol in different feeding mothers were measured.Results There were 219 subjects in the BOM group and 200 in the IUD group. The pregnancy rate in this two groups was 1. 43% and 1. 54% respectively. The rates of discontinuation and continuation in the IUD group were:8. 87% and 91. 35% as well as in the BOM group were 8. 53% and 90. 17% respectively. Neither result was statistically significant (P>0. 05). The experimtal research showed that menses return was well estimated by 0. 35 ratio of serum prolactin vs. estrodiol. Sensitivity and specificity was 94. 61% and 84. 61% respectively. It also indicated that (1) the levels of urine hormone were closely related to the patterns of cervical mucus and (2) the incidence of ovulating before the second return of menses in partially breastfeeding mothers was much lower than that of bottle-feeding mothers (47. 05% vs. 94. 20%). Conclusion BOM is a simple, reliable and well accepted contraceptive method of during breastfeeding. If it can be combined with the measurement of serum prolactin/ estradiol, the date of menses return will be determined more easily. Encouraging mothers to breast-feed will be beneficial to the health of both babies and mothers and delay the fertility return of mothers.
