Earliest Arrival Research Articles

Efficient Dynamic Flow Algorithms for Evacuation Planning Problems with Partial Lane Reversal

Contraflow technique has gained a considerable focus in evacuation planning research over the past several years. In this work, we design efficient algorithms to solve the maximum, lex-maximum, earliest arrival, and quickest dynamic flow problems having constant attributes and their generalizations with partial contraflow reconfiguration in the context of evacuation planning. The partial static contraflow problems, that are foundations to the dynamic flows, are also studied. Moreover, the contraflow model with inflow-dependent transit time on arcs is introduced. A strongly polynomial time algorithm to compute approximate solution of the quickest partial contraflow problem on two terminal networks is presented, which is substantiated by numerical computations considering Kathmandu road network as an evacuation network. Our results show that the quickest time to evacuate a flow of value 100,000 units is reduced by more than 42% using the partial contraflow technique, and the difference is more with the increase in the flow value. Moreover, the technique keeps the record of the portions of the road network not used by the evacuees.

Connection Scan Algorithm

We introduce the Connection Scan Algorithm (CSA) to efficiently answer queries to timetable information systems. The input consists, in the simplest setting, of a source position and a desired target position. The output consists of a sequence of vehicles such as trains or buses that a traveler should take to get from the source to the target. We study several problem variations such as the earliest arrival and profile problems. We present algorithm variants that only optimize the arrival time or additionally optimize the number of transfers in the Pareto sense. An advantage of CSA is that it can easily adjust to changes in the timetable, allowing the easy incorporation of known vehicle delays. We additionally introduce the Minimum Expected Arrival Time (MEAT) problem to handle possible, uncertain, future vehicle delays. We present a solution to the MEAT problem that is based on CSA. Finally, we extend CSA using the multilevel overlay paradigm to answer complex queries on nationwide integrated timetables with trains and buses.

The importance of core habitat for a threatened species in changing landscapes

Abstract Habitat loss, fragmentation, and alteration of the landscape matrix are interdependent processes, collectively responsible for most recent species extinctions. Thus, determining the extent to which these landscape processes affect animals is critical for conservation. However, researchers have often assumed that interdependent effects are independently related to animals’ responses, underestimating the importance of one or several landscape processes in driving species declines. We demonstrate how to disentangle the interdependent effects of habitat amount, fragmentation, and edge context on population size by assessing abundance of a rapidly declining grassland songbird species (grasshopper sparrow Ammodramus savannarum) in eastern Kansas (USA). We conducted >7,000 point count surveys at >2,000 sites over two breeding seasons, then modelled the direct, interactive, and indirect effects of landscape factors on abundance within spatial scales (200‐, 400‐, 800‐, and 1,600‐m radii) relevant to our focal species’ dispersal behaviour. Sparrow abundance correlated most strongly with landscape structure within 400‐m radii, increasing nonlinearly with grassland area and decreasing with the proportion of grassland near cropland or woody edges. Sparrows’ negative response to cropland edges was mostly an added, indirect consequence of reduced grassland area, whereas sparrows’ stronger negative response to woody edges was not attributable to variation in grassland area. Fragmentation and edge context mattered most in landscapes comprising c. 50%–80% grassland. Synthesis and applications. In our research, abundance of a threatened grassland songbird was influenced more by core grassland area (a function of total grassland area, fragmentation, and edge context) than total grassland area per se. Moreover, a local extinction threshold of c. 50% grassland indicated that small amounts of habitat were unsuitable for our focal species regardless of habitat configuration or matrix type. Local extinction thresholds in response to habitat area provide clear baseline targets for land managers; above those thresholds, configuration and the matrix can be modified to increase abundance of edge‐sensitive animals. Conflicting evidence in the literature regarding the importance of fragmentation and matrix features could be partially explained by species‐level traits, or methodological issues such as defining landscapes at ecologically arbitrary spatial scales, assessing landscape quality using species richness, and ignoring interactive and indirect effects.

Seven varieties of Arli: Skopje as a center of convergence and divergence of Romani dialects

Before the 1963 earthquake, Skopje was home to Romani dialects representing three major groups: South Vlax (Džambaz), Balkan II (Kovač or Burgudži), and South Balkan I (Arli). According to local tradition, there were seven Arli dialects spoken in Skopje: Topaanli, Barutči, Madžur, Konopar, Prištevač, Gilanli, and Gavutno. The author’s research confirmed this. The article selects phonological, morphological, and lexical features based on words and features that speakers themselves find emblematic in an attempt to tease out the differences among these dialects. What emerges is a clear divide between Topaanli, the oldest urban dialect, and Gavutno, the most recently arrived village dialect. The other dialects show a range of features between these two, with Barutči, the earliest arrival, closest to Topaanli. The other four show sets of commonalities and differences associated with contact languages, dialect contact, and separate developments. The urban–rural divide emerges as particularly significant, but the picture that emerges is best described in terms of a wave model rather than a branching model.

Shortest, Fastest, and Foremost Broadcast in Dynamic Networks

Highly dynamic networks rarely offer end-to-end connectivity at a given time. Yet, connectivity in these networks can be established over time and space, based on temporal analogues of multi-hop paths (also called journeys). Attempting to optimize the selection of the journeys in these networks naturally leads to the study of three cases: shortest (minimum hop), fastest (minimum duration), and foremost (earliest arrival) journeys. Efficient centralized algorithms exists to compute all cases, when the full knowledge of the network evolution is given. In this paper, we study the distributed counterparts of these problems, i.e. shortest, fastest, and foremost broadcast with termination detection (TDB), with minimal knowledge on the topology. We show that the feasibility of each of these problems requires distinct features on the evolution, through identifying three classes of dynamic graphs wherein the problems become gradually feasible: graphs in which the re-appearance of edges is recurrent (class [Formula: see text]), bounded-recurrent ([Formula: see text]), or periodic ([Formula: see text]), together with specific knowledge that are respectively n (the number of nodes), Δ (a bound on the recurrence time), and p (the period). In these classes it is not required that all pairs of nodes get in contact — only that the overall footprint of the graph is connected over time. Our results, together with the strict inclusion between [Formula: see text], [Formula: see text], and [Formula: see text], implies a feasibility order among the three variants of the problem, i.e. TDB[foremost] requires weaker assumptions on the topology dynamics than TDB[shortest], which itself requires less than TDB[fastest]. Reversely, these differences in feasibility imply that the computational powers of [Formula: see text], [Formula: see text], and [Formula: see text] also form a strict hierarchy.

Distribution, abundance and habitat of Palearctic migrants in Lesotho (Maloti/Drakensberg region)

In total 33 Palearctic migrant species have been recorded in Lesotho so far, but more than half of them are uncommon. The most common species include Ciconia ciconia (1.6 birds/10 km in river valleys and 5.1 birds/10 km outside river valleys), Falco naumanni, Falco amurensis, Actitis hypoleucos (2.1 birds/10 km in large highland rivers and 1.9 birds in Senque River in the lowlands), Phylloscopus trochilus and Muscicapa striata. Data on their densities along water courses and in open grasslands and farmlands in Lesotho are provided. The number of wintering Falco naumanni was estimated at 2,500–2,800 at eight roosts and that of wintering Falco amurensis at 850–900 at eight roosts. The earliest arrival and the latest departure dates are given for most species. In general, the wintering Palearctic bird fauna is poor and the species occur in low densities.

Trends of Elevated PTSD Risk in Firefighters Exposed to the World Trade Center Disaster: 2001–2005

We identified trends in the prevalence of elevated posttraumatic stress disorder (PTSD) risk as determined by the Fire Department of the City of New York (FDNY)-modified PTSD Checklist in World Trade Center (WTC)-exposed firefighters. We also examined trends in relation to WTC exposure, social support, change in recreational activities, and functional health. We analyzed 16,826 questionnaires from 10,074 firefighters in yearly intervals, from September 12, 2001, to September 11, 2005. The prevalence of elevated PTSD risk increased over time, from 9.8% in year 1 to 10.6% in year 4 (p < 0.0001). Earliest arrival at the WTC site (odds ratio [OR] = 6.0; 95% confidence interval [CI] 4.4, 8.3), prolonged work at the site (OR = 2.0; 95% CI 1.8, 2.3), providing supervision without previous supervisory experience (OR = 4.1; 95% CI 2.8, 6.1), and retirement due to a WTC-related disability (OR=1.3; 95% CI 1.1, 1.5) were associated with ever having elevated PTSD risk. Difficulty functioning at home was strongly associated with elevated PTSD risk (ORs ranged from 17.0 [95% CI 14.5, 20.0] in year 1 to 26.7 [95% CI 20.3, 35.2] in year 3), as was difficulty functioning at work (ORs ranged from 12.1 [95% CI 10.2, 14.2] in year 1 to 23.0 [95% CI 14.6, 36.3] in year 2). Elevated PTSD risk was associated with exposure to the WTC site as well as functional impairment, and remained largely unabated during the first four years of the study. Screening for elevated PTSD risk may be useful in identifying those who could benefit from interventions during long-term follow-up, as well as in the immediate aftermath of disasters.

Der Sommer und Herbst 2003 aus phänologischer Sicht | Summer and autumn 2003 from a phenological point of view

The record-breaking heatwave of 2003 also had an impact on the vegetation in Switzerland. To examine its influences seven phenological late spring and summer phases were evaluated together with six phases in the autumn from a selection of stations. 30% of the 122 chosen phenological time series in late spring and summer phases set a new record (earliest arrival). The proportion of very early arrivals is very high and the mean deviation from the norm is between 10 and 20 days. The situation was less extreme in autumn, where 20% of the 103 time series chosen set a new record. The majority of the phenological arrivals were found in the class «normal» but the class«very early» is still well represented. The mean precocity lies between five and twenty days. As far as the leaf shedding of the beech is concerned, there was even a slight delay of around six days. The evaluation serves to show that the heatwave of 2003 strongly influenced the phenological events of summer and spring.

Exploring for Knowledge

Exploration forms a fundamental part of both the prehistory and history of North America. From the earliest arrival of Asians and Europeans in the Americas, unknown territories had to be investigated, mapped, and assimilated into existing conceptions of cosmography, humanity, and religion. Surveying the land and its resources was an imperative for aggressive and avaricious European colonists, and, in the long international struggle for dominance in the Americas, usable geographical information constituted a coveted resource. Witness the many British and French efforts to find a passage to the Pacific and the alarm these efforts aroused in the minds of rival Spanish officials. Native peoples' long familiarity with the terrain gave them a critical advantage over newcomers in these struggles to comprehend and control North America, and acquisition of this native information, or at least some usable approximation thereof, was bound up with the advance of European expansion. In the history of the United States, exploration became assimilated into the mythology and memory of the West: Frederick Jackson Turner's evolving frontier is unimaginable without the explorer in his many forms. Historians of science are equally indebted to explorers, whose ventures into mysterious lands and waters opened new areas for European and American investigation in the eighteenth and nineteenth centuries; from James Cook to John Wesley Powell, the allure of scientific discovery has actuated exploration of North America as fully as have politics and profit. The drama of such expeditions inspired such classic studies of Western discovery and settlement as Bernard De Voto's The Course of Empire (Boston, 1952) and William H. Goetzmann's Exploration and Empire (New York, 1966). As such authors were well aware, western myth and European science resist simple separation, and in the story of American exploration, as of American history more generally, cultural ideas and representations shaped both the conduct of exploration and the understandings it generated. Accommodating a good portion of these numerous facets of American scientific exploration is the challenge faced by Surveying the Record, a collection of essays that features efforts to chart a new history of science and exploration in the American past. The sixteen papers

Weighted combination of size and disparity: a computational model for timing a ball catch.

How do we time hand closure to catch a ball? Binocular disparity and optical looming provide two sources of information about an object's motion in depth, but the relative effectiveness of the two cues depends on ball size. Based on results from a virtual reality ball-catching task, we derive a simple model that uses both cues. The model is sensitive to the relative effectiveness of size and disparity and implicitly switches its response to the cue that specifies the earliest arrival and away from a cue that is lost or below threshold. We demonstrate the model's robustness by predicting the response of participants to some very unusual ball trajectories in a virtual reality task.

The Georgia Dutch: from the Rhine and Danube to the Savannah, 1733-1783

This is the first comprehensive history of the German-speaking settlers who emigrated to the Georgia colony from Germany, Alsace, Switzerland, Austria, and adjacent regions. Known collectively as the Georgia Dutch, they were the colony's most enterprising early settlers, and they played a vital role in gaining Britain's toehold in a territory also coveted by Spain and France.The main body of the book is a chronological account of the Georgia Dutch from their earliest arrival in 1733 to their dispersal and absorption into what was, by 1783, an Anglo-American populace. Underscoring the harsh daily life of the common settler, George Fenwick Jones also highlights noteworthy individuals and events. He traces recurrent themes, including tensions between the realities of the settlers' lives and the aspirations and motivations of the colony's trustees and supporters; the web of relations between German- and English-speaking whites, African Americans, and Native Americans; and early signs of the genesis of a distinctly new and American sensibility.Three summary chapters conclude Georgia Dutch. Merging new material with information from previous chapters, Jones offers the most complete depiction to date of Georgia Dutch culture and society. Included are discussions of religion; health and medicine; education; welfare and charity; industry, agriculture, trade, and commerce; Native-American affairs; slavery; domestic life and customs; the arts; and military and legal concerns.Based on twenty-five years of research with primary documents in Europe and the United States, The Georgia Dutch is a welcome reappraisal of an ethnic group whose role in colonial history has, over time, been unfairly minimized.

The Beseda: The Czech National Dance in Cedar Rapids, Iowa

The nineteenth century brought a tidal wave of immigrants from many European countries to the United States. The immigrants tended to cluster in various areas across the country. One group came from what is now known as Czechoslovakia and settled in an area of eastern Iowa. Today, Cedar Rapids has the largest Czech community in the state. The population of the town and its metropolitan area is 125,000 and the Czech population is estimated at 30%, counting third and fourth generation Czechs.From their earliest arrival in the community around 1852 the Czechs congregated in an area that became known as “Little Bohemia,” where they formed their own community life. They continued their traditional hobbies of lace-making, egg-painting, theater, music, gymnastics, and dancing.

Fast hisslers in substorms

‘Fast hisslers,’ or very brief bursts of auroral hiss dispersed in the whistler mode, have been found to occur in substorms at Byrd station, Antarctica. Broad band VLF data recorded on tape during breakup phases of substorms were monitored aurally. In two of 19 substorm breakup phases observed at Byrd station, fast hisslers were heard. The data were subsequently spectrum analyzed to permit measurement of whistler mode dispersion, from which the altitudes of their origin were estimated. Some of the fast hisslers exhibited a ‘nose’ or nonextremal frequency of earliest arrival. This feature permitted an estimate of altitude of origin that is nearly independent of the field line electron density distribution model. Altitudes of origin of 1800–30,000 km are deduced. Some fast hisslers have been observed at phases other than the breakup phase. Fast Fourier transform spectra show that fast hisslers are indistinguishable from dispersed short pulses of band-limited white noise. Incoherent Cerenkov radiation from precipitating auroral electrons is of insufficient intensity to account for this phenomenon.

Some notes on the swans, and on the main factors that caused their extensive death at Odaito Bay, Nemuro, Hokkaido

There are two species of swans in Japan. One of them is the Whooper Swan, Cygnus cygnus and the other is the Eastern Bewick's Swan, Cygnus columbianus jankowskii. Both of them come from the northern and north-eastern parts of Siberia to Japan and spend some six months in this country as winter bird. The earliest arrival in Japan is late in October and the last departure is the 28th of April, according to the past observation records.The main wintering areas of swans are Lake Toro (Kushiro), Lake Furen and Odaito Bay (Nemuro), Lake Tofutsu (Abashiri), Lake Utonai (Tomakomai), etc., in Hokkaido. In Honshu they pass the winter at Ohminato Bay and Kominato Bay (Aomori Prefecture), Lake Hyo (Niigata Prefecture), etc. A small number of swans (1-8 individuals) occasionally visit Arasaki, Kyushu.It seems that Odaito Bay is the most important wintering area in Japan, since about ten thousand Whooper swans stay there for six months (Fig. 1). There is no other comparative wintering area in our country.Odaito Bay is located on the eastern part of Hokkaido, between Shiretoko Peninsula and Hanasaki Peninsula (Fig. 2). The area of Odaito is estimated at about 51, 840, 000 square meters. Many kinds of seaweeds are found in this region, providing suitable food for the swans. In addition, during the winter many speciesof ducks stay in this area.As far as I know, Eastern Bewick's swans are rarely found in Hokkaido, while there are comparatively many of them in Honshu.About 200 Whooper swans died because of the cold wave at Odaito Bay in February, 1967. A period of successive low temperatures continued for two weeks (Fig. 3) The temperature began to go down on the 8th of February. We had never before heard that a great number of swans died from cold and starvation.I visited Odaito Bay two times, just before and immediately after the accident, and found that there had occurred a remarkable reduction in the number of subadult swans.On the 12th of February, 1967, 106 sub-adults (11per cent) and 893 adults (89per cent) out of the total number of 999 swans were observed. On the 26th of February, 1967 only 15 sub-adults (2per cent) and 873 adults (98per cent) out of the total number of 888 swans were found. Incidentally, about 16per cent (329 out of 2, 047) for sub-adults and 84per cent (1, 718 out of 2, 047) for adults were observed at Odaito Bay on the 12th of February, 1966 (from the colour films taken at random).The percentages of the adults and sub-adults were estimated from the colour films which were taken at random at Odaito Bay.In order to determine the cause of death in adult and sub-adult swans autop-sies were taken. There was found no food in any crop of the dead swans. Although no green seaweeds were seen in the gizzards of two sub-adults (Fig. 4), some grits were found. On the other hand, in the gizzard of one adult was found a trace of green seaweeds.We could not find externally any symptoms of disease on the various internal organs.It has been found that when the swans were healthy excreted solid fecal pellets (Fig. 5-A), but when they were weak they excreted diarrheic pellets (Fig. 5-B).It is desirable to stir the surface of the water mechanically or to make ripples by bubbling with an air compressor in order to prevent freezing of the sea water on cold nights so that the swans may have access to the seaweeds.

The production of cosmic radiation by a solar flare on August 31, 1956

It is shown that the neutron counting rates observed by three widely separated recorders increased by approximately two percent about half an hour after the observation of an intense solar flare at 1226 U.T. on August 31, 1956. The event, as observed at all three stations, exhibited the abrupt onset, and gradual recovery typical of solar flare effects. The time delay between the first visual sighting of the flare, and the earliest arrival of cosmic radiation at the earth was about 20 min. It is shown that the quantity of cosmic radiation which arrived at the earth was two to three orders of magnitude less than the quantities which arrived during earlier flare effects. Consideration of the temporal dependence of the small flare effect suggests that only a small quantity of cosmic radiation was produced in the solar flare.