This paper presents the evaluation performance of a hybrid satellite constellation network which provides internet access based Transport Control Protocol (TCP). The evaluated satellite network uses the constellation ...This paper presents the evaluation performance of a hybrid satellite constellation network which provides internet access based Transport Control Protocol (TCP). The evaluated satellite network uses the constellation topology operating on Low Earth Orbit (LEO). The COMMStellationTM satellite system implemented using network simulator 2 (NS-2). In this paper, we modified a congestion window control based on TCP Westwood. The results show that the proposed technique reduces end-to-end (E2E) delay of transmitting packets. Hence the number of retransmission packets reduced.展开更多
Upon entering the military recruits are challenged physically, this is exceptionally difficult for women as their anatomy predisposes them to more impact injuries than men. Female military recruits are placed at a hig...Upon entering the military recruits are challenged physically, this is exceptionally difficult for women as their anatomy predisposes them to more impact injuries than men. Female military recruits are placed at a higher risk for shin splints, a repetition injury known in the medical field as medial tibial stress syndrome (MTSS). This review paper explores studies about MTSS, its prevalence, and expression in military recruits, particularly as its expression differs across gender. This paper will cover how the external environment of boot camp results in a higher prevalence of MTSS than the general population and how increased occurrence of MTSS in females has been attributed to specific physical attributes. This includes smaller tibial cross-sectional dimensions, greater than average hip range of motion, and differences in lower extremity mechanics during running and other repetitive physical activities. The external environment of boot camp coupled with these intrinsic factors highlight the importance of providing running education for women prior to arrival at boot camp and designing training regiments that account for these physiological differences.展开更多
Resilient Packet Ring （RPR）, or the Standard IEEE 802.17, is a new IP-based network technology proposed to replace SONET/SDH in metropolitan area networks. RPR is well-adapted to handle multimedia traffic and is eff...Resilient Packet Ring （RPR）, or the Standard IEEE 802.17, is a new IP-based network technology proposed to replace SONET/SDH in metropolitan area networks. RPR is well-adapted to handle multimedia traffic and is efficient. However, when RPR networks are bridged, inter-ring packets, or packets with the destination on a remote RPR network other than on the source network, are flooded on the source and the destination networks, and also on the path of the intermediate networks between the source and the destination networks. This decreases the available bandwidth for other traffic in those networks and is inefficient. As a result, we propose two solutions based on topology discovery, global topology discovery （GTD） and enhanced topology discovery （ETD）, that prevent the flooding of inter-ring packets. GTD enables the bridges to determine the next-hop bridge for each destination. ETD enables the source node to determine a default ringlet, so that packets reach the next-hop bridge without flooding the source network. The proposed solutions were analyzed and the overhead bandwidth and stabilization time were shown to be bounded. Simulations performed showed that the proposed solutions successfully avoid flooding and achieve optimal efficiency in the intermediate and destination networks, and in the source networks with one bridge.展开更多
investment of this type of business is not complex.Hence,the survival of this type of business is not easily guaranteed because of not only high competitiveness but also unclear information from the user side.Entrepre...investment of this type of business is not complex.Hence,the survival of this type of business is not easily guaranteed because of not only high competitiveness but also unclear information from the user side.Entrepreneurs of coworking spaces need to understand the characteristics and perspectives of users which may differ in various regions and cultures.This research investigated the users of coworking spaces in terms of their characteristics,behaviors,and perspectives.The scope focused on coworking spaces locating on or closed to the mass train transit stations of CBD Bangkok.The research applied quantitative approach through questionnaire surveys with 300 respondents during November,2017.There are many interesting results found from the analysis and somehow differ from past studies.The majority of respondents were younger than 25 years old who were students.However,a quarter of those were“Corporate Employee”.Coffee shop was the top place to work outside own office,seconded by coworking spaces.The behaviors of the majority of the respondents included:80%visited coworking spaces at least one a week and almost half visited 3-4 times a week;they spent at least three hours per visit and about 15%spent longer than six hours.The perspectives of most respondents were used coworking spaces to increase productivity and chose a place based on location.The results call for further analysis and studies.展开更多
This paper aims to examine the existence of calendar anomalies including month-of-year effect, turn-of-month effect, and weekend effect in Thai stock market. The stock return is computed from SET index during 1988 to ...This paper aims to examine the existence of calendar anomalies including month-of-year effect, turn-of-month effect, and weekend effect in Thai stock market. The stock return is computed from SET index during 1988 to 2009 and the SET50 index gathered since it was created in 1995. The unit root test is performed to ensure that the stock return series have no unit root. The multiple regression techniques using dummy variables are employed to test the difference of the return during each calendar anomalies period. If the regression model suffers from conditional heteroskedasticity, the GARCH （1, 1） model will be used instead of normal ordinary least square regression. It was found that the calendar anomalies exist in Thai stock market. The return is abnormally high during December and January, which can be addressed to be the turn-of-year effect. The return during the turn-of-month period, which can be defined as the last trading day and the first four trading days of the following months, is also abnormally high. Finally, the return is also abnormally high on Fridays but abnormally low on Mondays, which is addressed as weekend effect. This may create the opportunity to make above-average profit to investors exploiting these calendar anomalies. Although these calendar anomalies may be difficult to be exploited in practice because of transaction costs and ability to replicate the stock index, the existing evidence of calendar anomalies can help investors as the clue for the timing of investment.展开更多
文摘This paper presents the evaluation performance of a hybrid satellite constellation network which provides internet access based Transport Control Protocol (TCP). The evaluated satellite network uses the constellation topology operating on Low Earth Orbit (LEO). The COMMStellationTM satellite system implemented using network simulator 2 (NS-2). In this paper, we modified a congestion window control based on TCP Westwood. The results show that the proposed technique reduces end-to-end (E2E) delay of transmitting packets. Hence the number of retransmission packets reduced.
文摘Upon entering the military recruits are challenged physically, this is exceptionally difficult for women as their anatomy predisposes them to more impact injuries than men. Female military recruits are placed at a higher risk for shin splints, a repetition injury known in the medical field as medial tibial stress syndrome (MTSS). This review paper explores studies about MTSS, its prevalence, and expression in military recruits, particularly as its expression differs across gender. This paper will cover how the external environment of boot camp results in a higher prevalence of MTSS than the general population and how increased occurrence of MTSS in females has been attributed to specific physical attributes. This includes smaller tibial cross-sectional dimensions, greater than average hip range of motion, and differences in lower extremity mechanics during running and other repetitive physical activities. The external environment of boot camp coupled with these intrinsic factors highlight the importance of providing running education for women prior to arrival at boot camp and designing training regiments that account for these physiological differences.
文摘Resilient Packet Ring （RPR）, or the Standard IEEE 802.17, is a new IP-based network technology proposed to replace SONET/SDH in metropolitan area networks. RPR is well-adapted to handle multimedia traffic and is efficient. However, when RPR networks are bridged, inter-ring packets, or packets with the destination on a remote RPR network other than on the source network, are flooded on the source and the destination networks, and also on the path of the intermediate networks between the source and the destination networks. This decreases the available bandwidth for other traffic in those networks and is inefficient. As a result, we propose two solutions based on topology discovery, global topology discovery （GTD） and enhanced topology discovery （ETD）, that prevent the flooding of inter-ring packets. GTD enables the bridges to determine the next-hop bridge for each destination. ETD enables the source node to determine a default ringlet, so that packets reach the next-hop bridge without flooding the source network. The proposed solutions were analyzed and the overhead bandwidth and stabilization time were shown to be bounded. Simulations performed showed that the proposed solutions successfully avoid flooding and achieve optimal efficiency in the intermediate and destination networks, and in the source networks with one bridge.
文摘investment of this type of business is not complex.Hence,the survival of this type of business is not easily guaranteed because of not only high competitiveness but also unclear information from the user side.Entrepreneurs of coworking spaces need to understand the characteristics and perspectives of users which may differ in various regions and cultures.This research investigated the users of coworking spaces in terms of their characteristics,behaviors,and perspectives.The scope focused on coworking spaces locating on or closed to the mass train transit stations of CBD Bangkok.The research applied quantitative approach through questionnaire surveys with 300 respondents during November,2017.There are many interesting results found from the analysis and somehow differ from past studies.The majority of respondents were younger than 25 years old who were students.However,a quarter of those were“Corporate Employee”.Coffee shop was the top place to work outside own office,seconded by coworking spaces.The behaviors of the majority of the respondents included:80%visited coworking spaces at least one a week and almost half visited 3-4 times a week;they spent at least three hours per visit and about 15%spent longer than six hours.The perspectives of most respondents were used coworking spaces to increase productivity and chose a place based on location.The results call for further analysis and studies.
文摘This paper aims to examine the existence of calendar anomalies including month-of-year effect, turn-of-month effect, and weekend effect in Thai stock market. The stock return is computed from SET index during 1988 to 2009 and the SET50 index gathered since it was created in 1995. The unit root test is performed to ensure that the stock return series have no unit root. The multiple regression techniques using dummy variables are employed to test the difference of the return during each calendar anomalies period. If the regression model suffers from conditional heteroskedasticity, the GARCH （1, 1） model will be used instead of normal ordinary least square regression. It was found that the calendar anomalies exist in Thai stock market. The return is abnormally high during December and January, which can be addressed to be the turn-of-year effect. The return during the turn-of-month period, which can be defined as the last trading day and the first four trading days of the following months, is also abnormally high. Finally, the return is also abnormally high on Fridays but abnormally low on Mondays, which is addressed as weekend effect. This may create the opportunity to make above-average profit to investors exploiting these calendar anomalies. Although these calendar anomalies may be difficult to be exploited in practice because of transaction costs and ability to replicate the stock index, the existing evidence of calendar anomalies can help investors as the clue for the timing of investment.
