The Norwegian Sea Gyre – A Regulator of Iceland-Scotland Ridge Exchanges

The Norwegian Sea gyre (NSG) is a large body of Arctic intermediate water and deep dense overflow waters, which circulate counterclockwise within the Norwegian Sea. Argo float trajectories presented in this study suggest that the NSG attains its strongest and most focused flow downstream of a confluence of subarctic waters from the Iceland Sea and the Jan Mayen Ridge at steep bathymetry north of the Faroe slope. Based on hydrographic data from a meridional standard section across this flow (1988 to present), the first baroclinic estimate of the NSG circulation strength is provided. We, furthermore, show that the NSG circulation regulates key aspects of both the poleward Atlantic Water (AW) currents and the equatorward near-bottom and mid-depth flows in the Norwegian Sea – the main arteries of the Meridional Overturning Circulation. More specifically, we demonstrate close links between the NSG circulation and (i) the observed Faroe Bank Channel Overflow (FBCO) transport, (ii) variable depth of the main thermocline separating AW from the underlying colder and denser subarctic water masses, and (iii) satellite-derived sea-surface heights (SSHs) in the southern Nordic Seas. In general, a strong NSG and weak FBCO transport are associated with an uplifted thermocline and depressed SSH. Along a narrow band near the Norwegian and Shetland slopes, a strong NSG – oppositely – links to a depressed interface. Daily records of the FBCO transport, and satellite altimetry in a sensitive region north of the Iceland-Faroe Ridge, complement our hydrographic monitoring of the NSG strength. Together these records constitute valuable indicators for aspects of the Norwegian Sea physical oceanography, which likely have an impact on regional climate, ecology and biological productivity.

Lambert W Based Speed Reduction Model in Presence of Pedestrian Movements: Case Studies on Undivided Streets

Pedestrian movements sharing right-of-way with vehicular traffic have adverse impacts on the mobility of the traffic stream. Pedestrian movements both along and across the road often force drivers of approaching vehicles either to stop completely or to slow down and change the existing lane. It ultimately results in a decrease in stream speed. With the aim of determining the influence of pedestrian movements, the present study collected traffic data at a standard section (without pedestrian movements) and both traffic and pedestrian data at a pedestrian section (with considerable pedestrian movements). To determine the speed at the standard section, this paper presents a novel ‘Lambert W function’-based speed prediction model in the context of a two-lane undivided urban road. When stream speeds of the pedestrian section were compared to the stream speeds obtained through the speed prediction model at the same traffic volume condition in absence of pedestrians, a significant reduction was observed. This reduction in stream speed is governed by pedestrian parameters. A new pedestrian parameter ‘lateral position of pedestrian from the edge while walking along the road’ was conceived in this study along with few other parameters to predict Percent Speed Reduction (PSR). Intensities of these pedestrian parameters were observed varying over time which results in a high fluctuation in PSR within a range of 29% to 62%. Finally, this investigation forwards an empirical model of Percent Speed Reduction (PSR) to predict the stream speed in the presence of on-street pedestrian movements on undivided urban roads. The outcome of this paper will help transport planners to estimate the efficiency of pedestrian infrastructure projects before implementation.

Study of optimality of existing 10 kV overhead wire standard section scale

In the article, using the method of economic intervals using the principle of limiting the permissible increase in costs from the optimal ones, the existing scale of standard wire cross-sections of 10 kV lines was investigated and, as a result, it was established that the existing scale does not satisfy the conditions of optimality and a new scale was developed that satisfies the conditions of economy.

Dielectric characteristics of epoxy resin modified with tetraethoxysilane in the millimeter range

In this work, the influence of alkoxysilanes introduced into the epoxy resin was studied. That was done in order to study the possibility of using the obtained binders in composite materials with increased radio transparency in the millimetre microwave radio band. Determination of the modified epoxy resin dielectric characteristics in the millimetre microwave radio transparency was carried out by the waveguide method. The measuring complex consisted of a precision measuring line P1-31, a tunable generator on a Gann diode (30-38 GHz), a ferrite gate, and a section of a standard-section waveguide. Based on measurements of the minimum position displacement of the standing wave coefficient by known propagation constants, the free-space wavelength λ0 for a given operating frequency, and the critical wavelength in the waveguide λcr, the loss angle tangent tg(δ) and the permittivity ε were calculated. Calculations of the permittivity ε, the angle of the dielectric loss tg(δ) and the radio transparency loss-ΔР were performed in the MathСad. Moisture absorption of samples was determined by holding them in a desiccator with a humidity of 98 %. The samples were kept in a tightly closed desiccator for 24 hours at a temperature of 25 oC. In addition, the relative moisture absorption was determined using the increase in mass. It was found that the introduction of tetraethoxysilane in the composition in an amount of 1.5-3.5% leads to a decrease in the tangent of the dielectric loss angle. The optimum is observed in the range of the modifier concentration of 2.5-3.5%. This fact confirms that at these concentrations there is a complete interaction of TEOS alkoxygroups with epoxy resin epoxygroups.

Study on New Bolted T-Stub Connection with Inserted Plates under Axial and Cyclic Loads

The bolted T-stub connection joining beam with column is being widely applied. To enhance the energy dissipation capacity of conventional T-stub connections, two rectangular plates are proposed to be inserted between the T-stub and column, so that the T-stub flange can yield both under tensile and compressive loads. This study put forward a mechanical model of a new T-stub connection with inserted plates and investigated important factors that could affect its mechanical behavior through experimental tests. Thirty specimens were designed with different configurations that differed according to the existence or absence of inserted plates, the fabrication method and the width of inserted plates. These configurations were tested under axial and cyclic loading conditions, and results showed that the proposal aiming to improve the energy dissipation capacity was feasible. The mechanical model presented coincided with the test observation and data. The advent of two inserted plates elevated the load bearing capacity, stiffness and ductility of connections under compression, whereas in tension the properties were not substantially enhanced. The welded T-stub connections outperformed those cut from standard section steel. The energy dissipated by connections with inserted plates was about 150% of that by traditional connections without inserted plates. Only within a reasonable range can the increment of plate width promote the energy dissipation capacity of T-stub connections. The optimum width of plates in terms of energy consumption accounted for around 31% of the overall width of connections.

Extreme transport velocities of Antarctic Bottom Water flow through the deep Vema Channel

In April 2017 and in October 2018, a Russian expedition on the R/V “Akademik Sergey Vavilov” in the South-West Atlantic carried out measurements of temperature, salinity, and velocity over a standard section across the deep Vema Channel at 31(градус) 12(минут) S. Extremely high and extremely low velocities and transports of Atlantic Bottom Water (AABW) in the entire history of our observations over this section were found. In 2017, the maximum speed over the section reached 55 cm/s, and in 2018, it did not exceed 30 cm/s. In 2018, a core of high velocities in the bottom layers of the channel characteristic of the AABW flow was not found.

Study on the Optimum Flushing Volume of the Sewer System in South Tangerang City

<strong>Aims: </strong>This planning aims to obtain the optimum flush volume on the design of sewerage in South Tangerang City. <strong>Methodology and results:</strong> Factors affecting this flushing are the length of pipelines, the service area, and topographic conditions. The sewer drain that needs flushing is Line 1–WWTP since the minimum velocity is not eligible due to its relatively low average topographic slope. The flushing is required particularly for the Section 1–2. Hence, two alternatives were devised by dividing the Population Equivalent (PE) in Section 1–2 into three segments. Those alternatives were differentiated by the PE—20%, 5%, and 75% for Alternative 1; whereas 10%, 15%, and 75% for Alternative 2. Alternative 1 requires flushing on Section 1–1.1 since it has a d_min of 7 cm and v_min of 0.2585 m/s, yielding a flush volume of 3.94 m³ (0.0193 m³/s). Section 1.1–1.2 still needs flushing because this channel has a v_min of 0.4281 m/s and a qualified d_min of 15 cm, generating a flush volume of 7.89 m³ (0.2113 m³/s). Flushing is not necessary for Section 1.2–2 due to its sufficient d_min of 63 cm and v_min of 0.88 m/s. Alternative 2 requires flushing on Section 1–1.1 since it has a d_min of 7 cm and a v_min of 0.2585 m/s, resulting in a flush volume of 2.63 m³ (0.0193 m³/s). Section 1.1–1.2 still requires flushing on account of its v_min of 0.3877 m/s and the yielded flush volume of 18.4 m³ (0.2625 m³/s), though its d_min of 13 cm complies with the standard. Section 1.2–2 does not need flushing as it already has a d_min of 63 cm and a v_min of 0.88 m/s. The total flush volumes for Alternative 1 and Alternative 2 are 11.83 m³ and 21.04 m³, respectively. <strong>Conclusion, significance, and impact of the study: </strong>The total flush volume for Alternative 1 is 11.83 m³, while Alternative 2 is 21.04 m³. Thus, the optimum design having the least flush volume is Alternative 1.

Distribution of nadph-diaphorase positive structures of olfactory bulb of rats in ontogenesis

Aim: to identify peculiarities of distribution of NADPH-diaphorase (NADPH-d) positive structures in olfactory bulbs of rats of different age. Materials and Methods. The study was conducted on 22 white male rats. The object of research was olfactory bulbs of newborn rats – 1-3 days, suckling period – 7, 14, 21 days, infantile – 30 days, juvenile – 60, and mature – 180 days. The study was conducted on cryostat serial sections of olfactory bulbs (20 µm). Nitroxidergic structures were identified by histochemical labelling of NADPH-d (by Hope method). In a standard section, the area of NADPH-diaphorase-positive cells (100 in each case), surface area of glomeruli, the number of positive neurons surrounding a glomerulus, were measured. Results. In result of study it was found that in the olfactory bulb of rats of the studied age only groups of superficial and deep short-axon neurons and periglomerular neurons showed positivity to NADPH-d. The end product of reaction was distributed in somas and extensions of a part of cells with the density of distribution depending on the layer of the olfactory bulb and on the age of animals. Besides, positivity to the enzyme was also found in the central parts of glomeruli with distribution of diaphorase depending not on age, but rather on localization of glomeruli. Conclusion. Age-related transformations of positive subpopulation of neurons of olfactory bulb indicate active participation of NO in the processes of postnatal differentiation, growth and development of olfactory bulb.