Nutrient enrichment experiments with nitrogen (N) and phosphorus (P) were conducted with samples from two stationsin the coastal waters of Qingdao, China, during summer to identify limiting nutrients. In late July...Nutrient enrichment experiments with nitrogen (N) and phosphorus (P) were conducted with samples from two stationsin the coastal waters of Qingdao, China, during summer to identify limiting nutrients. In late July of 2009, low P concentrations andthe maximum photochemical efficiency of photosystem II (Fv/Fm) in the initial samples together with Fv/Fm and chlorophyll a (Chl a)responses to P addition indicated P limitation at the two stations. In early August, low P levels still limited phytoplankton growth atstation A. Fv/Fm and Chl a were the highest in the NP treatments at station B, suggesting an N/P co-limitation. In mid-September,nutrient concentrations and Fv/Fm were elevated and phytoplankton communities were healthy. Greater Fv/Fm and Chl a in the treat-ments with added P than those without the addition suggested potential P limitation at station A. Lack of Fv/Fm and Chl a responsesfollowing nutrient additions indicated N and P repletion at station B. At the end of July 2010, neither N nor P was limited at station B.Additionally, Fv/Fm coupled with 24-h-long nutrient enrichment experiments can be used to detect P limitation and N/P co-limitationto natural populations. This method can be more accurate for assessing co-limitation than the use of criteria of nutrient concentrationsand ratios as indicators, and can provide more rapid results than nutrient addition bioassays using chlorophyll response as an indica-tor, when a population is potentially limited. Compared with the two conventional methods, the results based on F,/F~ can also pro-vide more detailed information about physiological states of the populations.展开更多
Product development process management plays an important role in concurrent engineering (CE). The integration platform is a useful tool for effectively supporting the software development and integration. Based on th...Product development process management plays an important role in concurrent engineering (CE). The integration platform is a useful tool for effectively supporting the software development and integration. Based on the analysis of practical requirements for product development process management for CE, a CORBA-based integration platform of product development process management (IP-PDPM) is designed and developed. The design principles for IP-PDPM are described. The system architecture and functions of the platform are given, the key technologies for the implementation of IP-PDPM are presented, the application integration mechanism and its implementation techniques are also detailed.展开更多
文摘Nutrient enrichment experiments with nitrogen (N) and phosphorus (P) were conducted with samples from two stationsin the coastal waters of Qingdao, China, during summer to identify limiting nutrients. In late July of 2009, low P concentrations andthe maximum photochemical efficiency of photosystem II (Fv/Fm) in the initial samples together with Fv/Fm and chlorophyll a (Chl a)responses to P addition indicated P limitation at the two stations. In early August, low P levels still limited phytoplankton growth atstation A. Fv/Fm and Chl a were the highest in the NP treatments at station B, suggesting an N/P co-limitation. In mid-September,nutrient concentrations and Fv/Fm were elevated and phytoplankton communities were healthy. Greater Fv/Fm and Chl a in the treat-ments with added P than those without the addition suggested potential P limitation at station A. Lack of Fv/Fm and Chl a responsesfollowing nutrient additions indicated N and P repletion at station B. At the end of July 2010, neither N nor P was limited at station B.Additionally, Fv/Fm coupled with 24-h-long nutrient enrichment experiments can be used to detect P limitation and N/P co-limitationto natural populations. This method can be more accurate for assessing co-limitation than the use of criteria of nutrient concentrationsand ratios as indicators, and can provide more rapid results than nutrient addition bioassays using chlorophyll response as an indica-tor, when a population is potentially limited. Compared with the two conventional methods, the results based on F,/F~ can also pro-vide more detailed information about physiological states of the populations.
文摘Product development process management plays an important role in concurrent engineering (CE). The integration platform is a useful tool for effectively supporting the software development and integration. Based on the analysis of practical requirements for product development process management for CE, a CORBA-based integration platform of product development process management (IP-PDPM) is designed and developed. The design principles for IP-PDPM are described. The system architecture and functions of the platform are given, the key technologies for the implementation of IP-PDPM are presented, the application integration mechanism and its implementation techniques are also detailed.