Gale’s Economy with Multiple Turnpikes. “Weak” Turnpike Effect

2016 ◽  
Vol 63 (4) ◽  
pp. 355-374
Author(s):  
Emil Panek

In the vast literature on turnpike theory it is generally assumed that the model path – called the turnpike – to which in a long time period all the optimal processes are convergent, is uniquely determined. Its geometric image in the Gale’s model (in its stationary version) is a ray in the space of all states of the economy. We call it von Neumann’s ray. In this paper we evade the assumption of the uniqueness of this turnpike (von Neumann’s ray) and study the behaviour of the stationary Gale’s economy with the compact turnpikes’ bundle. We call it multilane turnpike. We present proofs for several variants of the “weak” multilane turnpike theorem in the stationary Gales’ economy.

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Olli-Pekka Hilmola ◽  
Andres Tolli ◽  
Ain Kiisler

Abstract This study analyses 98 Internet pages of sea ports located in Sweden, Finland and Estonia during years 2017–2019. Aim of the study is to find, how website basic design is completed (colours and languages), how slogans, environmental issues, statistics and hinterland transports are reported. Based on the analysis, it appears as rather common that sea ports follow conservative selection of colours in their websites, where blue and white are clearly most popular. Typically, English and Swedish are as the most common used language, followed by Finnish, Russian and Estonian. In some rare cases, websites are offered in Chinese or German. Larger sea ports do have clear “slogans”, where smaller ones are just having lengthy justification for their existence. Environmental issues are increasing concern among sea ports, and these are mostly mentioned in details within Swedish actors. Providing statistics varies among companies, and in some sea ports these are provided from very long time period, where in others from just previous years or then only from last year (or even at all). It is common for companies to report that they have sustainable hinterland access, railway available.


2009 ◽  
Vol 90 (6) ◽  
pp. 1095-1104 ◽  
Author(s):  
Cathy H. Lucas ◽  
Adam J. Reed

Observations on gonad morphology and the structure of ovaries and testes of the coronate scyphozoans Atolla wyvillei and Periphylla periphylla are described based on samples collected from the Gulf of Mexico and Cape Hatteras (north-western Atlantic). In A. wyvillei, gonads of distinguishable sex were observed in medusae as small as 17 mm bell diameter (BD). Spermatogenesis occurred within follicles (average 366 × 254 μm) that were evenly distributed throughout the gonad. Oocytes in different stages of development were observed in all the females with gonads. Oocytes arise from the gastrodermis and migrate into the mesoglea to develop from early-mid to late vitellogenic oocytes characterized by a large nucleus and granular (organic-rich) cytoplasm. The largest oocytes measured were 543 μm and 263 μm from the Gulf of Mexico and Cape Hatteras respectively. Possible reasons for this difference are discussed. In P. periphylla gonads were also initially observed in medusae 17 mm BD, although not all larger medusae had obvious gonads. Unlike A. wyvillei sperm follicles were arranged in long convoluted rows normally only one follicle thick. The organization of ooytes in female P. periphylla was very similar to A. wyvillei, although the gonads were small and the number of oocytes present in each gonad very low (<22). The largest oocyte measured was 777 μm in a 53 mm BD medusa. Although medusae were collected from one time period only (September) in this study, our findings appear to be in agreement with literature evidence indicating that coronate jellyfish produce few eggs continuously over a long time period. Aspects of gonad development and gametogenesis are discussed with respect to potential differences in site productivity and species identification.


Author(s):  
Hironori Nakagami

Abstract There is currently an outbreak of respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus disease 2019 (COVID-19) is caused by infection with SARS-CoV-2. Individuals with COVID-19 have symptoms that are usually asymptomatic or mild in most initial cases. However, in some cases, moderate and severe symptoms have been observed with pneumonia. Many companies are developing COVID-19 vaccine candidates using different technologies that are classified into four groups (intact target viruses, proteins, viral vectors and nucleic acids). For rapid development, RNA vaccines and adenovirus vector vaccines have been urgently approved, and their injection has already started across the world. These types of vaccine technologies have been developed over more than 20 years using translational research for use against cancer or diseases caused by genetic disorders but the COVID-19 vaccines are the first licensed drugs to prevent infectious diseases using RNA vaccine technology. Although these vaccines are highly effective in preventing COVID-19 for a short period, safety and efficiency evaluations should be continuously monitored over a long time period. As the time of writing, more than 10 projects are now in phase 3 to evaluate the prevention of infection in double-blind studies. Hopefully, several projects may be approved to ensure high-efficiency and safe vaccines.


2017 ◽  
Vol 12 (1) ◽  
Author(s):  
Ulrik B. Pedersen ◽  
Dimitrios-Alexios Karagiannis-Voules ◽  
Nicholas Midzi ◽  
Tkafira Mduluza ◽  
Samson Mukaratirwa ◽  
...  

Temperature, precipitation and humidity are known to be important factors for the development of schistosome parasites as well as their intermediate snail hosts. Climate therefore plays an important role in determining the geographical distribution of schistosomiasis and it is expected that climate change will alter distribution and transmission patterns. Reliable predictions of distribution changes and likely transmission scenarios are key to efficient schistosomiasis intervention-planning. However, it is often difficult to assess the direction and magnitude of the impact on schistosomiasis induced by climate change, as well as the temporal transferability and predictive accuracy of the models, as prevalence data is often only available from one point in time. We evaluated potential climate-induced changes on the geographical distribution of schistosomiasis in Zimbabwe using prevalence data from two points in time, 29 years apart; to our knowledge, this is the first study investigating this over such a long time period. We applied historical weather data and matched prevalence data of two schistosome species (<em>Schistosoma haematobium</em> and <em>S. mansoni</em>). For each time period studied, a Bayesian geostatistical model was fitted to a range of climatic, environmental and other potential risk factors to identify significant predictors that could help us to obtain spatially explicit schistosomiasis risk estimates for Zimbabwe. The observed general downward trend in schistosomiasis prevalence for Zimbabwe from 1981 and the period preceding a survey and control campaign in 2010 parallels a shift towards a drier and warmer climate. However, a statistically significant relationship between climate change and the change in prevalence could not be established.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Matthew Joseph ◽  
Aaron Roth ◽  
Jonathan Ullman ◽  
Bo Waggoner

There are now several large scale deployments of differential privacy used to collect statistical information about users. However, these deployments periodically recollect the data and recompute the statistics using algorithms designed for a single use. As a result, these systems do not provide meaningful privacy guarantees over long time scales. Moreover, existing techniques to mitigate this effect do not apply in the “local model” of differential privacy that these systems use. In this paper, we introduce a new technique for local differential privacy that makes it possible to maintain up-to-date statistics over time, with privacy guarantees that degrade only in the number of changes in the underlying distribution rather than the number of collection periods. We use our technique for tracking a changing statistic in the setting where users are partitioned into an unknown collection of groups, and at every time period each user draws a single bit from a common (but changing) group-specific distribution. We also provide an application to frequency and heavy-hitter estimation.


2009 ◽  
Vol 47 (2-3) ◽  
Author(s):  
R. Tatevossian

To evaluate the completeness of modern knowledge on historical seismicity it is necessary to know the general geopolitical and socio-cultural background in the country. It determines the possibility to record the evidence of an earthquake and conserve the record in original form for a long time-period. The potential duration of historical earthquake study in Russia is assessed based on these considerations. Certain stages of earthquake study in Russia have been detected. Specific problems of seismicity studies of low active areas are discussed as an example of Russian platform. The value of each (even moderate magnitude) event becomes crucial for seismic hazard assessment in such territories. A correct identification of event nature (tectonic earthquake or exogenous phenomena - landslides, karsts, etc.) is practically impossible without using primary sources with detailed descriptions. Occurrence of modern earthquakes can be used to assess the accuracy of historical seismicity knowledge.


2021 ◽  
Author(s):  
Johan Westerman ◽  
Dirk Witteveen ◽  
Erik Bihagen ◽  
Roujman Shahbazian

There is a wide-spread idea that contemporary careers continue to become ever more complex. Pioneering research of full-career complexity has shown that work lives have indeed become more complex, yet at modest increasing pace. This paper examines whether career complexity continues to increase using Swedish registry data across an exceptionally long time period, including younger cohorts than in previous research: up to those born in 1983. The full early- and midcareers of selected birth cohorts cover several macroeconomic booms and downturns, a long period of upskilling of the Swedish labor force, as well as the convergence of working hours of women and men. The following conclusions are drawn using state-of-the-art methods of measuring career complexity. For early-careers, an increasing complexity trend is evident between the 1950s and 1960s birth cohorts, yet complexity fluctuates around a stable trend for the 1970s birth cohorts and onward. For mid-careers, which are considerably more stable on average, complexity has decreased among women born between the 1930s and the early-1950s. However, the opposite trend holds true for men, resulting in gender convergence of complexity. We observe a standstill of the mid-career complexity trend across both genders, followed by a modest decline for the last observed cohorts. Subsequent analyses point to educational expansion as an important driver of the initial increase of early-career complexity. Taken together, our analysis affirms an initial shift to more career complexity in the 20th century, yet we find no unidirectional trend toward more career complexity over the last decades.


Author(s):  
Emilia CONSTANTINESCU ◽  
Dorina BONEA ◽  
M. STEFAN ◽  
Luminita SANDU ◽  
M. GIORGOTA

Of the analysis of the soil and clime conditions that are characteristic for the ash deposits as well as from the observations on the behavior of an enriched array of species, on these terrains there was observed the possibility of obtaining good results with the peanuts crop on the terrains covered by powerplant ash. There was chosen the Arachis hypogaea L. due to its capacity to capitalize the ash covered terrains, as well as by protecting by its vegetal mass a long time period of the vegetation period, decreasing the ash drift and the reduction of the environment pollution that is near the ash deposits. In supporting this species there was considered the thermic favorable regime of the zone, the high sunshine, the light texture, high water permeability of the deposited material, the plant density to the surface unit and the covering degree of the terrain by vegetal mass, that are favorable features in controlling the ash drift and environment pollution.


2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Yinlan Shen ◽  
Haibin Zhou ◽  
Shuo Xue ◽  
Jinchuan Zhang

Wood truss joist floors are increasingly used to replace traditional solid timber joist floors in low-rise timber houses. An understanding of the vibration performance of wood truss joist floors is critical for the design and serviceability of the floors. It is difficult to model wood truss joist floors accurately because of the complicated boundary conditions and numerous sophisticated flexible connections. This paper discusses three simplified modeling methods for the wood truss joist floor system. The modeling results were validated by a series of static deflection tests and vibration modes and frequencies tests of a full-size floor. And predictive analysis of human-induced vibration of the floor was also conducted. The vibration characteristics of the wood truss joist floor were investigated. The examination of the applicability of these modeling methods was provided. The results indicate that the point loading deflection more easily affects the deflection of the adjacent joist. However, the deflection influence on other joists that are three spaces away is minimal. Walking on the wood truss joist floor produces steep vibration acceleration fluctuations at the floor center for a relatively long time period. The sheathing-to-joist connections and the metal plate connections of the joists have significant influences on the vibration response of the wood truss joist floor. The modeling method, which considers the flexible metal plate connections and flexible sheathing-to-joist connections, performs best for predicting the vibration performance of the floor.


2020 ◽  
Vol 8 (2) ◽  
pp. 383
Author(s):  
Mukhaila Iryani ◽  
Yusnita Yusnita ◽  
Dwi Hapsoro ◽  
Kukuh Setiawan ◽  
Agus Karyanto

Hybrid moth orchid (genus Phalaenopsis) is one of the most popular ornamentals in Indonesia. It has beautiful and long-lasting flowers, but cultivating this orchid is still become a challenging issues due to the need of specific condition to grow and long time period to re-blooming. Plant growth regulators (PGR) (i.e. Benzyladenine (BA)) has been widely documented as a flower-inducing substance in several orchids. However, the optimal concentration and its mechanism in inducing flower-stalk bud and re-blooming is still unclear. This research aimed to study the effects of BA application in the form of lanolin paste on hybrid Phalaenopsis flower-stalk buds. We conducted this study using completely randomized design with four replications at the greenhouse laboratory Faculty of Agriculture University of Lampung on August to December 2018. We divided the orchid into 5 group of BA concentration (0, 1000, 1500, 3000, or 6000 ppm). The sheath of the fourth or fifth buds of the flowers were carefully opened, then it smeared with BA. The percentage of bud break into flower spike or keiki, length of shoots or spike and number of open flowers were recorded until 10 weeks of observation. The results showed that, neither of the buds under the control treatment (without BA), 1000 ppm nor 1500 ppm BA broke and grew into keiki or spike. On the other hand, application of BA at 3000 ppm or 6000 ppm successfully induced 100% flower spikes on the buds treated. No keiki was formed in all buds treated. In addition, treatment of the buds with 6000 ppm BA produced longer flower spikes as well as more open flowers. We conclude that the application of BA (minimal 3000 ppm) successfully induced flower spike of  hybrid Phalaenopsis.


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