Oasis Greenways: A New Model of Urban Park within Street Right-of-Ways in Dorchester, Massachusetts

Parks and greenways can offer many benefits to urban communities in many areas including recreational, public health, and increased land value. However, there are often few opportunities to carve out a narrow, continuous green space in the built-up parts of our cities. One prospect involves using available land in rail or utility corridors; another involves radical road diets to create space along major roads. This paper examines another approach, using the right-of-way (ROW) of local streets to transform pavement into linear parks that we call Oasis Greenways. An Oasis Greenway has ultra-low motor vehicle speeds and volumes, allowing there to be a single, narrow paved area shared by motor traffic, pedestrians, and bicycles. The resulting reduction in road footprint creates space for vegetation bordering the paved area, turning the street into a path through greenway park. This paper describes the development of an Oasis Greenway concept and its application to the Fairmount Corridor in Dorchester, a neighborhood of Boston identified as a “Greenway Desert” (Furth et al, 2013)

Raman scattering reveals strong LO-phonon-hole-plasmon coupling in nominally undoped GaAsBi: optical determination of carrier concentration

We report room-temperature Raman scattering studies of nominally undoped (100) GaAs1−xBix epitaxial layers exhibiting Biinduced (p-type) longitudinal-optical-plasmon coupled (LOPC) modes for 0.018≤x≤0.048. Redshifts in the GaAs-like optical modes due to alloying are evaluated and are paralleled by strong damping of the LOPC. The relative integrated Raman intensities of LO(Γ) and LOPC ALO/ALOPC are characteristic of heavily doped p-GaAs, with a remarkable near total screening of the LO(Γ) phonon (ALO/ALOPC →0) for larger Bi concentrations. A method of spectral analysis is set out which yields estimates of hole concentrations in excess of 5 × 1017 cm−3 and correlates with the Bi molar fraction. These findings are in general agreement with recent electrical transport measurements performed on the alloy, and while the absolute size of the hole concentrations differ, likely origins for the discrepancy are discussed. We conclude that the damped LO-phonon-hole-plasmon coupling phenomena plays a dominant role in Raman scattering from unpassivated nominally undoped GaAsBi

Enhancement of terahertz photoconductive antenna operation by optical nanoantennas

Photoconductive antennas are promising sources of terahertz radiation that is widely used for spectroscopy, characterization, and imaging of biological objects, deep space studies, scanning of surfaces, and detection of potentially hazardous substances. These antennas are compact and allow for generation of both ultrabroadband pulses and tunable continuous wave terahertz signals at room temperatures, with no need for high-power optical sources. However, such antennas have relatively low energy conversion efficiency of femtosecond laser pulses or two close pump wavelengths (photomixers) into the pulsed and continuous terahertz radiation, correspondingly. Recently, an approach to solving this problem that involves known methods of nanophotonics applied to terahertz photoconductive antennas and photomixers has been proposed. This approach comprises the use of optical nanoantennas for enhancing the absorption of pump laser radiation in the antenna gap, reducing the lifetime of photoexcited carriers, and improving the antenna thermal efficiency. This Review is intended to systematize the main results obtained by researchers in this promising field of hybrid optical-to-terahertz photoconductive antennas and photomixers. We summarize the main results on hybrid THz antennas, compare the approaches to their implementation, and offer further perspectives of their development including an application of all-dielectric nanoantennas instead of plasmonic ones

Interim Brigade Combat Team (IBCT) Munitions Distribution Study

This research sought to describe an alternative way for calculating expected back order (EBO) for reparable inventory systems. The high costs associated with reparable items management, together with its importance for system\u27s availability, make the assessment of back orders of great importance in supporting decisions of what-to-buy and where-to-locate those items. Starting at the point that existing models (METRIC, MOD-METRIC, and VARIMETRIC) rely on some assumptions that often cannot be met in real life, the proposed method (called P-METRIC), which is a mix of simulation and mathematical analytical model, relaxes assumptions about Demand, Time to Repair (TTR), and Ordering & Ship Time (OST) distributions looking for potential differences that may cause on the EBO calculation. The study consists of 10 conceptual examples where the parameters of Demand, TTR, and OST vary according to probability distributions recognized by the related literature. It also presents a case study of 20 reparable items of the T-27 Tucano, an advanced-training, light-attack deployed by the Brazilian Air Force. EBO numbers of the existing and proposed models are compared with results gathered from simulation (conceptual examples) and a field research (T-27 Tucano) in order to allow conclusions about the accuracy and suitability of the proposed method

Comprehension of the tax administration.

Due to the recent years’ deficit State Budget of the Republic of Lithuania, a particular attention while forming the Budget income is being focused on the quality of tax administration. In order to define the sets of competent institutions and their functions, the Law on the tax administration adopted by the Parliament of the Republic of Lithuania in 1995, for the first time consolidated the comprehension of the tax administration. Up till now the majority of authors only indicate in the sources of law the comprehension of the tax administration established by the law, but do not analyse it. Some of them (Assoc. prof. B. Sudavičius, Dr. J. Rimas) also give a more detailed definition of this phenomenon. According to them, tax administration is the practice of the tax administrator, the institution directly responsible for collection and control of taxes as well as of other executive and legislative institutions of government and courts. The reason of such interpretation is the diversity of meanings of the term ¥administration” in the public law. This article generalizes the meaning of the term ¥public administration” usage in the Lithuanian administrative law. On the basis of this generalization, relating to the public administration as to the enforcement and execution of law, the comprehension of the tax administration is being analysed.Dėl deficitinio pastarųjų metų Lietuvos valstybės biudžeto daug dėmesio formuojant biudžeto pajamas kreipiama į mokesčių administravimo kokybę. Kompetentingoms institucijoms ir jų funkcijoms apibrėžti 1995 m. priimtas Lietuvos Respublikos mokesčių administravimo įstatymas pirmą kartą įtvirtino mokesčių administravimo sampratą. Iki šiol dauguma autorių mokesčių teisės šaltiniuose pateikia įstatyme nustatytą mokesčių administravimo sampratą, bet jos nenagrinėja. Kai kurie iš jų (B. Sudavičius, J. Rimas), pateikia ir platesnį šio reiškinio apibrėžimą. Jų manymu, mokesčių administravimas – tai ne tik mokesčių administratoriaus ir tiesiogiai už mokesčių surinkimą ir kontrolę atsakingos institucijos, bet ir kitų įstatymų vykdomosios ir įstatymų leidžiamosios valdžios institucijų bei teismų praktinė veikla. Pagrindas tokiam interpretavimui – termino ¥administravimas” daugiareikšmiškumas viešojoje teisėje. Šiame straipsnyje apibendrinama termino ¥viešasis administravimas” vartojimo Lietuvos administracinėje teisėje reikšmė. Šio apibendrinimo pagrindu viešąjį administravimą suprantant kaip įstatymų įgyvendinimą ir vykdymą analizuojama mokesčių administravimo samprata