Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies...Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies on human perception, and major emphasis on the saliently similar aspect of objects to be compared is placed and thus the search result is more agreeable for users. After relevant results are obtained, the cluster-based browsing algorithm is adopted for search result presentation based on social network analysis. By organizing the results in clustered lists, the user can have a general understanding of the whole collection by viewing only a small part of results and locate those of major interest rapidly. Experimental results demonstrate the advantages of the proposed algorithm over the traditional work.展开更多
Among mobile users, ad-hoc social network (ASN) is becoming a popular platform to connect and share their interests anytime anywhere. Many researchers and computer scientists investigated ASN architecture, implementat...Among mobile users, ad-hoc social network (ASN) is becoming a popular platform to connect and share their interests anytime anywhere. Many researchers and computer scientists investigated ASN architecture, implementation, user experience, and different profile matching algorithms to provide better user experience in ad-hoc social network. We emphasize that strength of an ad-hoc social network depends on a good profile-matching algorithm that provides meaningful friend suggestions in proximity. Keeping browsing history is a good way to determine user’s interest, however, interests change with location. This paper presents a novel profile-matching algorithm for automatically building a user profile based on dynamic GPS (Global Positing System) location and browsing history of users. Building user profile based on GPS location of a user provides benefits to ASN users as this profile represents user’s dynamic interests that keep changing with location e.g. office, home, or some other location. Proposed profile-matching algorithm maintains multiple local profiles based on location of mobile device.展开更多
In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of lear...In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of learner. We conduct a comparative study for various ensemble methods (Bagging, Boosting, and Voting) with simple classifiers in perspective of classification. We also evaluate the effectiveness of these classifiers (both ensemble and simple) on five different data sets of varying session length. Presently the results of web server log analyzers are not very much reliable because the input log files are highly inflated by sessions of automated web traverse software’s, known as web robots. Presence of web robots access traffic entries in web server log repositories imposes a great challenge to extract any actionable and usable knowledge about browsing behavior of actual visitors. So web robots sessions need accurate and fast detection from web server log repositories to extract knowledge about genuine visitors and to produce correct results of log analyzers.展开更多
Forest pasturing of free-roaming livestock is a common prac- tice in many parts of the world, but knowledge on how it affects tree regeneration in boreal forests is lacking. We mapped tree density, live- stock site us...Forest pasturing of free-roaming livestock is a common prac- tice in many parts of the world, but knowledge on how it affects tree regeneration in boreal forests is lacking. We mapped tree density, live- stock site use and accumulated damage to young trees of commercial interest （Norway spruce, Picea abies L. Karst.） on 56 clearcuts inside and outside a fenced forest area used for livestock pasturing in Ringsaker, Norway. Inside the fence 56-1.8% of spruce trees were damaged com- pared to 37-3.4% outside. Proportion of damaged spruce trees was posi- tively related to cattle use of the clearcut, but not so for sheep. On the most intensively used clearcuts, four out of five trees were damaged. The density of deciduous trees was five times lower inside compared to out- side of the fence （varying with plant species）. While livestock grazing may reduce resource competition in favour of spruce, the current animal density clearly is impeding forest regeneration in the study area.展开更多
Deer, particularly white-tailed deer (Odocoileus virginianus), damage row crops such as soybean (Glycine max L.) and are a perceived problem in the continental US. Currently, the only widely used technique to control ...Deer, particularly white-tailed deer (Odocoileus virginianus), damage row crops such as soybean (Glycine max L.) and are a perceived problem in the continental US. Currently, the only widely used technique to control deer from crop browsing is establishment of fences, which is expensive, labor intensive, and most of the time ineffective. Studies have shown that sicklepod, Senna obtusifolia (L.), contains anthraquinone derivatives, which in separate studies were shown to be toxic to cattle, rats, rabbits, and horses, and repel herbivores primarily birds. However, information of the deer-repelling property of anthraquinone in sicklepod is lacking. Field tests conducted at our Captive Deer Facility at MississippiStateUniversity(MSU) confirmed the deer-repelling property of anthraquinone extracts from sicklepod. Soybean plants applied with control treatment (water) were browsed by deer, while plants applied with sicklepod anthraquinone extracts were avoided. Using chromatography techniques, we found the levels of anthraquinone derivatives (chrysophanol, emodin) in sicklepod plant parts in the order: root > fruit > stem/leaf. Hydrolysis of water extracts of sicklepod seed produced high emodin concentration, suggesting emodin glycoside as the main form of anthraquinone glycoside in sicklepod seed. Deer-repelling compounds can be extracted in its pure form from sicklepod and applied on soybean to increase its repelling efficacy on deer, and at the same time protect soybean yields.展开更多
Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. Herbivory by North American elk and domestic cattle is a contentious management issue throughout weste...Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. Herbivory by North American elk and domestic cattle is a contentious management issue throughout western North America, often driving management proposals to decrease cattle and elk numbers based on perceived overutilization of forages. Such observations are often site level rather than landscape, and may confuse ecological sustainability with desired conditions. Methods： We used line transects to document vegetation composition, structure, and grazing and browsing utilization for 4 key habitat types： mountain meadows, aspen, thinned conifer, and burned conifer on Lincoln National Forest, New Mexico, USA. We documented relative habitat use of these types by elk, mule deer, and cattle and modeled relative use on residual grass biomass of mountain meadows and browse utilization of forested types. We determined diets and diet quality of elk and cattle to assess degree of competition. Results： Use of grasses in meadows was below management thresholds, and combined elk, cattle, and deer relative habitat use accounted for 〈 14 % of the variance in residual stubble height of Poa protensis, the most abundant grass. Palatable browse was limited in habitat types （〈 107 stems.ha^-1）, use was generally high, and elk presence was correlated with the majority of browsing. Elk and cattle diets did not significantly overlap （Schoener＇s index 0.54-0.57）; elk fed primarily on deciduous shrubs （34 %-55 % of annual diets） and cattle on grass （72 %-77 %）. Digestibility and crude protein levels of cattle diets and body condition of elk indicated high quality diets for cattle and marginal-good quality diets for elk. Conclusions： At observed stocking levels and densities, cattle and elk were not competing for forage based on diet similarity, nor were key habitat types being used beyond sustainable levels. Low browse availability indicates that opportunity exists to increase forage availability展开更多
In eastern North America, white-tailed deer(Odocoileus virginianus) can have profound influences on forest biodiversity and forest successional processes.Moderate to high deer populations in the central Appalachians h...In eastern North America, white-tailed deer(Odocoileus virginianus) can have profound influences on forest biodiversity and forest successional processes.Moderate to high deer populations in the central Appalachians have resulted in lower forest biodiversity.Legacy effects in some areas persist even following deer population reductions or declines. This has prompted managers to consider deer population management goals in light of policies designed to support conservation of biodiversity and forest regeneration while continuing to support ample recreational hunting opportunities. However,despite known relationships between herbivory intensity and biodiversity impact, little information exists on the predictability of herbivory intensity across the varied and spatially diverse habitat conditions of the central Appalachians. We examined the predictability of browsing rates across central Appalachian landscapes at four environmental scales: vegetative community characteristics, physical environment, habitat configuration, and local human and deer population demographics. In an information-theoretic approach, we found that a model fitting the number of stems browsed relative to local vegetation characteristics received most(62%) of the overall support of all tested models assessing herbivory impact. Our data suggest that deer herbivory responded most predictably to differences in vegetation quantity and type. No other spatial factors or demographic factors consistently affected browsing intensity. Because herbivory, vegetation communities, and productivity vary spatially, we suggest that effective broad-scale herbivory impact assessment should include spatially-balanced vegetation monitoring that accounts for regional differences in deer forage preference.Effective monitoring is necessary to avoid biodiversity impacts and deleterious changes in vegetation community composition that are difficult to reverse and/or may not be detected using traditional deer-density based management goals.展开更多
Fire is regarded as management practice for maintaining grasslands and savannas. The vegetation occurring in fire prone areas becomes highly adapted to fire occurrences in savannas and grasslands. However, documentati...Fire is regarded as management practice for maintaining grasslands and savannas. The vegetation occurring in fire prone areas becomes highly adapted to fire occurrences in savannas and grasslands. However, documentation on the influence of burning on vegetation is still limited in an albany thicket biome. The aim of the study was to evaluate the short-term influence of burning on species abundance, biomass production, wood plant density and browsing unit. Six plots (2500 m<sup>2</sup>) were demarcated;in each plot two parallel transects of 120 m<sup>2</sup> with 5 m distance apart were measured. Three plots were burned in spring season, while no burning was done on the other remaining plots. Forty points per plot were obtained using step-point method to determine the relative abundance at burned and unburned plots. Woody plants occurred within a transect were identified, counted and recorded to determine density and browsing unit. Three quadrats (<em>i.e</em>. 0.25 m<sup>2</sup>) per plot were randomly laid within the transect;aboveground plant material within a quadrat were harvested. A total of 18 samples were harvested and oven dried at 60<span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span>C for 48 hours to determine biomass production. The results showed that <em>Themeda triandra</em> (14%) and <em>Panicum maximum</em> (10%) were most abundant grass species at the burned plots. Burned plots had significantly higher biomass production (4804 kg/ha) compared to unburned plots (3641 kg/ha). <em>Vachellia karoo</em> (burned: 65.85% & unburn: 13.70%) and <em>Searsia pallens </em>(burned: 26.83% & unburned: 6.85%) were most dominant wood plant species at both burned and unburned plots. Burned plots had the highest browsing unit (3221 BU/ha) compared to unburned plots (2058 BU/ha). The decrease of woody plants at the burned plots proved that fire has a tremendous potential for managing woody plants. This study provided information on short-term influence of burning, however further展开更多
Video adaptation is a promising technique to bridge the gap between network status, device capabilities, and user preferences in pervasive media applications. However, conventional adaptation frameworks based on eithe...Video adaptation is a promising technique to bridge the gap between network status, device capabilities, and user preferences in pervasive media applications. However, conventional adaptation frameworks based on either transcoding or multiple pre-transcoding are not able to accommodate large numbers of users with diversified applications. This paper introduces an intermediate video description called ＂Inter- media＂, which consists of multiple level video signal components, such as texture, motion, and rate control information, as well as some semantic features, such as structural characteristics and Region Of Interest （ROI） information. It is generated off-line and stored in the video server or media gateway. Intermedia is then used to design a novel video adaptation system. The proposed adaptation system quickly and easily generates the required bit stream from Intermedia with very low complexity to fulfill a series of specific adaptation requirements, e.g., bitrate conversion, temporal/spatial resolution reduction, video summarization, ROI browsing, and some multi-level adaptations involving both signal level and semantic level adaptation. The satisfactory performance of such a system demonstrates the effectiveness and efficiency of the proposed video adaptation framework.展开更多
基金Supported by the Fund for Basic Research of National Non-Profit Research Institutes(No.XK2012-2,ZD2012-7-2)the Fund for Preresearch Project of ISTIC(No.YY201208)
文摘Similarity matching and this paper, a saliency-based information presentation are two matching algorithm is proposed key factors in information retrieval. In for user-oriented search based on the psychological studies on human perception, and major emphasis on the saliently similar aspect of objects to be compared is placed and thus the search result is more agreeable for users. After relevant results are obtained, the cluster-based browsing algorithm is adopted for search result presentation based on social network analysis. By organizing the results in clustered lists, the user can have a general understanding of the whole collection by viewing only a small part of results and locate those of major interest rapidly. Experimental results demonstrate the advantages of the proposed algorithm over the traditional work.
文摘Among mobile users, ad-hoc social network (ASN) is becoming a popular platform to connect and share their interests anytime anywhere. Many researchers and computer scientists investigated ASN architecture, implementation, user experience, and different profile matching algorithms to provide better user experience in ad-hoc social network. We emphasize that strength of an ad-hoc social network depends on a good profile-matching algorithm that provides meaningful friend suggestions in proximity. Keeping browsing history is a good way to determine user’s interest, however, interests change with location. This paper presents a novel profile-matching algorithm for automatically building a user profile based on dynamic GPS (Global Positing System) location and browsing history of users. Building user profile based on GPS location of a user provides benefits to ASN users as this profile represents user’s dynamic interests that keep changing with location e.g. office, home, or some other location. Proposed profile-matching algorithm maintains multiple local profiles based on location of mobile device.
文摘In this paper we investigate the effectiveness of ensemble-based learners for web robot session identification from web server logs. We also perform multi fold robot session labeling to improve the performance of learner. We conduct a comparative study for various ensemble methods (Bagging, Boosting, and Voting) with simple classifiers in perspective of classification. We also evaluate the effectiveness of these classifiers (both ensemble and simple) on five different data sets of varying session length. Presently the results of web server log analyzers are not very much reliable because the input log files are highly inflated by sessions of automated web traverse software’s, known as web robots. Presence of web robots access traffic entries in web server log repositories imposes a great challenge to extract any actionable and usable knowledge about browsing behavior of actual visitors. So web robots sessions need accurate and fast detection from web server log repositories to extract knowledge about genuine visitors and to produce correct results of log analyzers.
基金partly funded by the Research Council of Norway,project#215647/E40(Intensified harvesting of forests–implications for enterprises related to wild and domestic ungulates)
文摘Forest pasturing of free-roaming livestock is a common prac- tice in many parts of the world, but knowledge on how it affects tree regeneration in boreal forests is lacking. We mapped tree density, live- stock site use and accumulated damage to young trees of commercial interest （Norway spruce, Picea abies L. Karst.） on 56 clearcuts inside and outside a fenced forest area used for livestock pasturing in Ringsaker, Norway. Inside the fence 56-1.8% of spruce trees were damaged com- pared to 37-3.4% outside. Proportion of damaged spruce trees was posi- tively related to cattle use of the clearcut, but not so for sheep. On the most intensively used clearcuts, four out of five trees were damaged. The density of deciduous trees was five times lower inside compared to out- side of the fence （varying with plant species）. While livestock grazing may reduce resource competition in favour of spruce, the current animal density clearly is impeding forest regeneration in the study area.
文摘Deer, particularly white-tailed deer (Odocoileus virginianus), damage row crops such as soybean (Glycine max L.) and are a perceived problem in the continental US. Currently, the only widely used technique to control deer from crop browsing is establishment of fences, which is expensive, labor intensive, and most of the time ineffective. Studies have shown that sicklepod, Senna obtusifolia (L.), contains anthraquinone derivatives, which in separate studies were shown to be toxic to cattle, rats, rabbits, and horses, and repel herbivores primarily birds. However, information of the deer-repelling property of anthraquinone in sicklepod is lacking. Field tests conducted at our Captive Deer Facility at MississippiStateUniversity(MSU) confirmed the deer-repelling property of anthraquinone extracts from sicklepod. Soybean plants applied with control treatment (water) were browsed by deer, while plants applied with sicklepod anthraquinone extracts were avoided. Using chromatography techniques, we found the levels of anthraquinone derivatives (chrysophanol, emodin) in sicklepod plant parts in the order: root > fruit > stem/leaf. Hydrolysis of water extracts of sicklepod seed produced high emodin concentration, suggesting emodin glycoside as the main form of anthraquinone glycoside in sicklepod seed. Deer-repelling compounds can be extracted in its pure form from sicklepod and applied on soybean to increase its repelling efficacy on deer, and at the same time protect soybean yields.
基金the U.S.Forest Service,Rocky Mountain Elk Foundation,New Mexico Department of Game and Fish,and several private entities for funding this projectThe New Mexico State University,Agricultural Experiment Station provided additional financial support
文摘Background： Wildlife and livestock grazing are important products of forest ecosystems, but can be controversial. Herbivory by North American elk and domestic cattle is a contentious management issue throughout western North America, often driving management proposals to decrease cattle and elk numbers based on perceived overutilization of forages. Such observations are often site level rather than landscape, and may confuse ecological sustainability with desired conditions. Methods： We used line transects to document vegetation composition, structure, and grazing and browsing utilization for 4 key habitat types： mountain meadows, aspen, thinned conifer, and burned conifer on Lincoln National Forest, New Mexico, USA. We documented relative habitat use of these types by elk, mule deer, and cattle and modeled relative use on residual grass biomass of mountain meadows and browse utilization of forested types. We determined diets and diet quality of elk and cattle to assess degree of competition. Results： Use of grasses in meadows was below management thresholds, and combined elk, cattle, and deer relative habitat use accounted for 〈 14 % of the variance in residual stubble height of Poa protensis, the most abundant grass. Palatable browse was limited in habitat types （〈 107 stems.ha^-1）, use was generally high, and elk presence was correlated with the majority of browsing. Elk and cattle diets did not significantly overlap （Schoener＇s index 0.54-0.57）; elk fed primarily on deciduous shrubs （34 %-55 % of annual diets） and cattle on grass （72 %-77 %）. Digestibility and crude protein levels of cattle diets and body condition of elk indicated high quality diets for cattle and marginal-good quality diets for elk. Conclusions： At observed stocking levels and densities, cattle and elk were not competing for forage based on diet similarity, nor were key habitat types being used beyond sustainable levels. Low browse availability indicates that opportunity exists to increase forage availability
基金financially supported by the Wildlife and Sport Fish Restoration Program,Project WE99,Contract 2012-13694 to Virginia Tech
文摘In eastern North America, white-tailed deer(Odocoileus virginianus) can have profound influences on forest biodiversity and forest successional processes.Moderate to high deer populations in the central Appalachians have resulted in lower forest biodiversity.Legacy effects in some areas persist even following deer population reductions or declines. This has prompted managers to consider deer population management goals in light of policies designed to support conservation of biodiversity and forest regeneration while continuing to support ample recreational hunting opportunities. However,despite known relationships between herbivory intensity and biodiversity impact, little information exists on the predictability of herbivory intensity across the varied and spatially diverse habitat conditions of the central Appalachians. We examined the predictability of browsing rates across central Appalachian landscapes at four environmental scales: vegetative community characteristics, physical environment, habitat configuration, and local human and deer population demographics. In an information-theoretic approach, we found that a model fitting the number of stems browsed relative to local vegetation characteristics received most(62%) of the overall support of all tested models assessing herbivory impact. Our data suggest that deer herbivory responded most predictably to differences in vegetation quantity and type. No other spatial factors or demographic factors consistently affected browsing intensity. Because herbivory, vegetation communities, and productivity vary spatially, we suggest that effective broad-scale herbivory impact assessment should include spatially-balanced vegetation monitoring that accounts for regional differences in deer forage preference.Effective monitoring is necessary to avoid biodiversity impacts and deleterious changes in vegetation community composition that are difficult to reverse and/or may not be detected using traditional deer-density based management goals.
文摘Fire is regarded as management practice for maintaining grasslands and savannas. The vegetation occurring in fire prone areas becomes highly adapted to fire occurrences in savannas and grasslands. However, documentation on the influence of burning on vegetation is still limited in an albany thicket biome. The aim of the study was to evaluate the short-term influence of burning on species abundance, biomass production, wood plant density and browsing unit. Six plots (2500 m<sup>2</sup>) were demarcated;in each plot two parallel transects of 120 m<sup>2</sup> with 5 m distance apart were measured. Three plots were burned in spring season, while no burning was done on the other remaining plots. Forty points per plot were obtained using step-point method to determine the relative abundance at burned and unburned plots. Woody plants occurred within a transect were identified, counted and recorded to determine density and browsing unit. Three quadrats (<em>i.e</em>. 0.25 m<sup>2</sup>) per plot were randomly laid within the transect;aboveground plant material within a quadrat were harvested. A total of 18 samples were harvested and oven dried at 60<span style="white-space:nowrap;"><span style="white-space:nowrap;">˚</span></span>C for 48 hours to determine biomass production. The results showed that <em>Themeda triandra</em> (14%) and <em>Panicum maximum</em> (10%) were most abundant grass species at the burned plots. Burned plots had significantly higher biomass production (4804 kg/ha) compared to unburned plots (3641 kg/ha). <em>Vachellia karoo</em> (burned: 65.85% & unburn: 13.70%) and <em>Searsia pallens </em>(burned: 26.83% & unburned: 6.85%) were most dominant wood plant species at both burned and unburned plots. Burned plots had the highest browsing unit (3221 BU/ha) compared to unburned plots (2058 BU/ha). The decrease of woody plants at the burned plots proved that fire has a tremendous potential for managing woody plants. This study provided information on short-term influence of burning, however further
基金Supported by the National Natural Science Foundation of China(No.60736043)
文摘Video adaptation is a promising technique to bridge the gap between network status, device capabilities, and user preferences in pervasive media applications. However, conventional adaptation frameworks based on either transcoding or multiple pre-transcoding are not able to accommodate large numbers of users with diversified applications. This paper introduces an intermediate video description called ＂Inter- media＂, which consists of multiple level video signal components, such as texture, motion, and rate control information, as well as some semantic features, such as structural characteristics and Region Of Interest （ROI） information. It is generated off-line and stored in the video server or media gateway. Intermedia is then used to design a novel video adaptation system. The proposed adaptation system quickly and easily generates the required bit stream from Intermedia with very low complexity to fulfill a series of specific adaptation requirements, e.g., bitrate conversion, temporal/spatial resolution reduction, video summarization, ROI browsing, and some multi-level adaptations involving both signal level and semantic level adaptation. The satisfactory performance of such a system demonstrates the effectiveness and efficiency of the proposed video adaptation framework.
