Questing for Quality Estimation A User Study

Post-Editing of Machine Translation (MT) has become a reality in professional translation workflows. In order to optimize the management of projects that use post-editing and avoid underpayments and mistrust from professional translators, effective tools to assess the quality of Machine Translation (MT) systems need to be put in place. One field of study that could address this problem is Machine Translation Quality Estimation (MTQE), which aims to determine the quality of MT without an existing reference. Accurate and reliable MTQE can help project managers and translators alike, as it would allow estimating more precisely the cost of post-editing projects in terms of time and adequate fares by discarding those segments that are not worth post-editing (PE) and have to be translated from scratch. In this paper, we report on the results of an impact study which engages professional translators in PE tasks using MTQE. We measured translators? productivity in different scenarios: translating from scratch, post-editing without using MTQE, and post-editing using MTQE. Our results show that QE information, when accurate, improves post-editing efficiency.E

On the effectiveness of an optimization method for the traffic of TCP-based multiplayer online games

This paper studies the feasibility of using an optimization method, based on multiplexing and header compression, for the traffic of Massively Multiplayer Online Role Playing Games (MMORPGs) using TCP at the Transport Layer. Different scenarios where a number of flows share a common network path are identified. The adaptation of the multiplexing method is explained, and a formula of the savings is devised. The header compression ratio is obtained using real traces of a popular game and a statistical model of its traffic is used to obtain the bandwidth saving as a function of the number of players and the multiplexing period. The obtained savings can be up to 60 % for IPv4 and 70 % for IPv6. A Mean Opinion Score model from the literature is employed to calculate the limits of the multiplexing period that can be used without harming the user experience. The interactions between multiplexed and non-multiplexed flows, sharing a bottleneck with different kinds of background traffic, are studied through simulations. As a result of the tests, some limits for the multiplexing period are recommended: the unfairness between players can be low if the value of the multiplexing period is kept under 10 or 20 ms. TCP background flows using SACK (Selective Acknowledgment) and Reno yield better results, in terms of fairness, than Tahoe and New Reno. When UDP is used for background traffic, high values of the multiplexing period may stress the unfairness between flows if network congestion is severe

AN OBSERVATIONAL STUDY OF TICKS ON THE 30 ACRE LAKE TRAIL AT TURNBULL NATIONAL WILDLIFE REFUGE

Ticks are known carriers of bacterial pathogens that cause diseases in humans and other mammals. Hosts (mice, chipmunks, rabbits, deer, and elk) must be in the tick’s questing range to fulfill the life cycle. The questing range depends on the life stage of the tick, vegetation, and host accessibility. Mammal densities directly affect the number of questing ticks observed in the environment. The 30 Acre Lake Trail site was selected for this study due to the high density of Dermacentor species ticks observed in past studies and the only known site of Rickettsia rickettsii pathogen isolated from ticks on the Turnbull National Wildlife Refuge (TNWR) to date. I hypothesize that there is a risk of infection of Rickettsia at this location, given the large tick density as well as the large density of competent hosts. I trapped small mammals four days per week for six weeks from 30 March 2016 to 18 May 2016. Ticks were collected once per week in all zones off the 30 Acre Lake Trail. Tick DNA was extracted for sequencing to identify Rickettsia bacteria. There were 33 ticks that were positive for Rickettsia spp. bacteria of the 472 that were tested. Less than one percent were positive for Rickettsia rickettsii. A vegetation survey was performed and a percentage of cover was determined for each zone. More ticks were found in areas with more chipmunks and less deer mice and higher percentage of shrub vegetation. The possibility of a Rickettsia infection is present at the 30 Acre Lake Trail

MOOSE HABITAT USE DURING CRITICAL PERIODS IN THE WINTER TICK LIFECYCLE AND AGENT-BASED MODELING OF MOOSE-WINTER TICK RELATIONSHIPS IN NORTHERN NEW HAMPSHIRE

High calf mortality has been documented in North American moose (Alces alces) populations along the southern extent of their range; in New England, this has been attributed to winter tick (Dermacentor albipictus) parasitism. This research was conducted to better understand moose activity during critical periods in the winter tick life cycle, and to assess the potential of simulation models in managing moose against future epizootics. Seasonal habitat use was measured using geospatial analyses of locational data from radio-marked animals at 3 sites in New Hampshire and Maine. An agent-based model, spatially explicit to two subsections of the New Hampshire field site (Success and Jericho), was then constructed to simulate the role of moose density, weather events, winter tick abundance and aggregation, and proportion of available optimal habitat on % mortality and tick infestation level of dead calves. The average size of home and core ranges generally increased from south to north, following the population gradient. Optimal habitat was the only land cover type used above its availability (1.1-2.1X availability in home range, 1.2-3.1X availability in core range), regardless of season or site, indicating that moose were selecting for this cover type during questing and drop-off periods of winter ticks. The proportional overlap of cut habitat in home and core ranges exceeded the absolute proportion in home and core ranges. It is expected that temporal use of optimal habitat exceeds the geospatial estimates because 30-40% of the daily activity of moose is spent foraging. The high proportion of time spent foraging within optimal habitat that is available in disproportionately low proportion (\u3c 20%) across the landscape suggests that high concentrations of winter ticks are available in this cover type. The model was parameterized using empirical data acquired from the literature and results of the current field study. Of 58 combinations of variables, 17 produced epizootic events (calf mortality \u3e 50%), of which 15 occurred in Jericho where the availability of optimal habitat was higher (28%) than the study site average (17%). Averages of the two sites under conditions representative of the current moose density and recent weather conditions yielded similar, albeit lower, calf mortality (53-66%) and infestation level (37,635 ticks/calf) than measured in the field study (~70% calf mortality, 48,600 ticks/calf). Winter tick abundance and aggregation both influenced the occurrence and severity of infestation and mortality at each site. While the model used a conservative approach with regard to several parameters (e.g., moose activity, winter tick abundance, % ticks that desiccate during drought, and moose density), it produced patterns and trends congruent with those calculated during the field study, and demonstrated the future management potential of this method

Enhanced threat of tick-borne infections within cities? Assessing public health risks due to ticks in urban green spaces in Helsinki, Finland

Most tick-related studies in Europe have been conducted in nonurban areas, but ticks and tick-borne pathogens also occur in urban green spaces. From a public health perspective, risks regarding tick-borne infections should be studied in these urban areas, where contacts between infected ticks and humans may be more frequent than elsewhere, due to high human activity. We examined the risk of encountering an infected tick in urban green spaces in Helsinki, Finland. We collected ticks at nine sites throughout Helsinki, recorded the prevalence of several pathogens and identified areas with a high potential for contacts between infected ticks and humans. Moreover, we explored the relationship between the density ofBorrelia burgdorferisensu lato-infected ticks and locally diagnosed cases of borreliosis and compared the potential for human-tick encounters in Helsinki to those in nonurban areas in south-western Finland. During 34.8 km of cloth dragging, 2,417Ixodes ricinuswere caught (402 adults, 1,399 nymphs and 616 larvae). From analysed nymphs, we found 11 distinct tick-borne pathogens, with 31.5% of nymphs carrying at least one pathogen. Tick activity was highest in August and September, leading to the density of nymphs infected withB. burgdorferis.l., and concurrently infection risk, to also be highest during this time. Nymph densities varied between the sampling sites, with obvious implications to spatial variation in infection risk. While ticks and tick-borne pathogens were found in both Helsinki and nonurban areas in south-western Finland, the estimates of human activity were generally higher in urban green spaces, leading to a higher potential for human-tick contacts therein. The presence of ticks and tick-borne pathogens and high local human activity in urban green spaces suggest that they form potential foci regarding the acquisition of tick-borne infections. Risk areas within cities should be identified and knowledge regarding urban ticks increased.peerReviewe

Analyzing the effect of tcp and server population on massively multiplayer games

Many Massively Multiplayer Online Role-Playing Games (MMORPGs) use TCP flows for communication between the server and the game clients. The utilization of TCP, which was not initially designed for (soft) real-time services, has many implications for the competing traffic flows. In this paper we present a series of studies which explore the competition between MMORPG and other traffic flows. For that aim, we first extend a source-based traffic model, based on player’s activities during the day, to also incorporate the impact of the number of players sharing a server (server population) on network traffic. Based on real traffic traces, we statistically model the influence of the variation of the server’s player population on the network traffic, depending on the action categories (i.e., types of in-game player behaviour). Using the developed traffic model we prove that while server population only modifies specific action categories, this effect is significant enough to be observed on the overall traffic. We find that TCP Vegas is a good option for competing flows in order not to throttle the MMORPG flows and that TCP SACK is more respectful with game flows than other TCP variants, namely, Tahoe, Reno, and New Reno. Other tests show that MMORPG flows do not significantly reduce their sending window size when competing against UDP flows. Additionally, we study the effect of RTT unfairness between MMORPG flows, showing that it is less important than in the case of network-limited TCP flows

Do changes in regulation affect employment duration in temporary work agencies?

"Over the past three decades Germany has repeatedly deregulated the law on temporary agency work by stepwise increasing the maximum period for hiring-out employees and allowing temporary work agencies to conclude fixed-term contracts. These reforms should have had an effect on the employment duration within temporary work agencies. Based on an informative administrative data set we use hazard rate models to examine whether the employment duration has changed in response to these reforms. We find that the repeated prolongation of the maximum period for hiring-out employees significantly increased the average employment duration while the authorization of fixed-term contracts reduced employment tenure." (Author's abstract, IAB-Doku) ((en))Leiharbeit, Regulierung, Deregulierung, Arbeitnehmerüberlassungsgesetz - Reform, Leiharbeitnehmer, Beschäftigungsdauer, labour turnover, Zeitarbeit, befristeter Arbeitsvertrag, Lohnunterschied, Lohnhöhe, Tariflohn, IAB-Beschäftigtenstichprobe