One-way System Research Articles

Basic Properties of One-Way Action Hydraulic Percussion System with Two Piston Arresters

Basic Properties of One-Way Action Hydraulic Percussion System with Two Piston Arresters

Atmospheric refractivity estimation from AIS signal power using the quantum-behaved particle swarm optimization algorithm

Abstract This paper proposes a new refractivity profile estimation method based on the use of AIS signal power and quantum-behaved particle swarm optimization (QPSO) algorithm to solve the inverse problem. Automatic identification system (AIS) is a maritime navigation safety communication system that operates in the very high frequency mobile band and was developed primarily for collision avoidance. Since AIS is a one-way communication system which does not need to consider the target echo signal, it can estimate the atmospheric refractivity profile more accurately. Estimating atmospheric refractivity profiles from AIS signal power is a complex nonlinear optimization problem, the QPSO algorithm is adopted to search for the optimal solution from various refractivity parameters, and the inversion results are compared with those of the particle swarm optimization algorithm to validate the superiority of the QPSO algorithm. In order to test the anti-noise ability of the QPSO algorithm, the synthetic AIS signal power with different Gaussian noise levels is utilized to invert the surface-based duct. Simulation results indicate that the QPSO algorithm can invert the surface-based duct using AIS signal power accurately, which verify the feasibility of the new atmospheric refractivity estimation method based on the automatic identification system.

One-way thermo-responsive shape memory polymer nanocomposite derived from polycaprolactone and polystyrene-block-polybutadiene-block-polystyrene packed with carbon nanofiber

Shape-memory polymer nanocomposite (SMPNC) blends with thermoresponsive shape memory capability have received increasing interests and have been a grooming research area due to its potential applications. In the present study, the polymer blend comprising of Polycaprolactone (PCL) and Polystyrene-block-Polybutadiene-block-Polystyrene (SBS) is prepared by melting and blending method, followed by the addition of carbon nanofibers (CNF), to provide the blend with excellent shape memory property stimulated by temperature. In this polymeric blend SBS, PCL, and CNF are acted as an elastomer, switch polymer and conductive filler, respectively. The two-phase morphology of components in the blend is confirmed using Scanning Electrode Microscopic (SEM) images, Polarised Optical Microscopic (POM) images, and stress-strain plots. The immiscibility between the microstructures is revealed from the Differential Scanning Calorimetric (DSC) results. Characterization techniques such as X-Ray Diffraction (XRD), Thermo Gravimetric Analysis (TGA) and shape memory test are also conducted. The crystallinity of the synthesized composite is influenced by the PCL content. As the PCL content increases, crystalline nature also increases. From TGA results, the thermal stability of the composites is found to be decreasing from PCL 5 to PCL 100. The tensile and shape memory results show an optimized one-way SMPNC system with good shape recovery and fixing performances.

Dynamic prediction-based relocation policies in one-way station-based carsharing systems with complete journey reservations

In this paper, we study the operations of a one-way station-based carsharing system implementing a complete journey reservation policy. We consider the percentage of served demand as a primary performance measure and analyze the effect of several dynamic staff-based relocation policies. Specifically, we introduce a new proactive relocation policy based on Markov chain dynamics that utilizes reservation information to better predict the future states of the stations. This policy is compared to a state-of-the art staff-based relocation policy and a centralistic relocation model assuming full knowledge of the demand. Numerical results from a real-world implementation and a simulation analysis demonstrate the positive impact of dynamic relocations and highlight the improvement in performance obtained with the proposed proactive relocation policy.

Decrease in water level by rooter technology one-way system on flood-prone land in Sunggal District, North Sumatra, Indonesia

Rooter system technology is a technology used to accommodate and absorb water into the soil through pipes that are designed like tree roots where the pipe is planted into the ground as deep as two meters with a slope of 45 degrees. Rainwater is collected and absorbed into the soil. Rooter technology system only holds rainwater, it does not waste water. System rooter technology is a well or hole on the ground surface which is made to hold rainwater so that it can seep into the soil. This study aims to control flooding in flood-prone areas using one-way rooter technology with an environmentally friendly concept. This research was conducted from 1 January 2018 to 28 February 2018 by observing directly in the field. Observations carried out included analysis of the study site, the water level at the study site, area of land affected by flooding, length of time, the soil absorbed, water level which did not use one-way rooter system technology. The volume of water that entered the soil was calculated using both rooter system technology and land that does not consume system rooter technology. The results of this study indicated that by using rooter technology a one-way water system is faster to enter the ground and can overcome flooding on the land.

Analysis of One-Way System Implementation with Contra-Flow Bus Lane in Supporting Sustainable Transportation Program

Traffic development in the central business district area along the Brigjend Slamet Riyadi road, Surakarta City, Indonesia, is relatively dense and not in accordance with the development and changes in the environmental situation. This phenomenon creates congestion on several roads and intersections. Transport planning related to traffic management and engineering, and infrastructure needs to be carried out to solve urban transportation problems. Based on the Surakarta City Government’s vision related to sustainable transportation, the one-way system with contra-flow bus lane will be implemented along the Brigjend Slamet Riyadi road. With the existence of this system, it is hoped that public transport Batik Solo Trans as one solution of urban transportation problem can be more integrated, fast, safe, comfortable, reliable and efficient. The purpose of this research is to determine the impact of the implementation of one-way system with contra-flow bus lane to the traffic performance in the study area. The research methodology involves modelling and analysing the traffic performance, parking and potential public transport demand in the study area. The existence of one-way system with contra-flow bus lane has the potential to increase the use of public transportation and improve the performance of public transportation. In general, traffic performance decreases, therefore it is necessary to perform transportation demand management such as management parking.

Financial Development and Economic Growth Nexus: Evidence From Algeria Lien entre développement financier et croissance économique: témoignages de l'Algérie

This research paper represents a brief summary of both the theoretical and theempirical frameworks of the most important researches related to the study of therelationship between financial development and economic growth. A standard study wasconducted to investigated the nature of the relationship and to determine the role of theAlgerian banking system in promoting the economic activity during the period (1990 –2014) relying on a set of tests, including the test of cointegration of variables, and vectorerror-correction model. In addition to Granger’s causality, using only the financialvariables, and then applying the model using macro variables (financial and realvariables) as to identify the most influential factors on economic growth .The study concluded that there is a one-way long-term causal relationship betweenbanking system and economic growth. While the Granger’s causality test indicates a onewaycausal relationship between economic growth and investments.

BENTUK PENATAAN KAWASAN DAN PERMUKIMAN KAMPUNG AUR MEDAN

The Settlement Area in Kampung Aur is a densely populated settlement located on the banks of the Deli River in Medan. Until now there has not been a more appropriate solution to the arrangement of the area and its residents although there are in several cities there have been several types of solutions to the problem of densely populated settlements ranging from forced evictions, the construction of new settlements in the form of flat / flat and village improvement programs. That said, the government began to realize that the problem could not be solved by a one-way system. There must be communication with slum dwellers. This then encourages the authors to make an arrangement of the area and its residents with an approach to the behavior of citizens and the types of settlements at this time. This study aims to produce a design of the area and settlements that can accommodate social and cultural aspects of society through the approach of environmental behavior and types of settlements. To achieve this goal, participatory observation will be carried out in every dominant community in the location. Through this observation it will be seen how the environmental settings and behavior work in Kampung Aur. Data on environmental and behavioral settings will then be processed to produce Kampung Aur design completion criteria. From this study it was found that there are two dominant tribes in Kampung Aur, namely Chinese and Minang.

Development of Road Network Traffic Model in Bandung City

The city of Bandung is a city with a higher number of movements; thus, it allows congestion on certain road segments. Constructing and widening new roads do not become the only solutions, but also by improving the traffic management on these roads. With the study area in some segments of Wastu Kencana Street, Cihampelas, Pajajaran, Pasir Kaliki, Kebon Kawung, and Cicendo, some of which have frequent congestion. Several alternatives have been assessed to implement traffic management policies. The solution alternatives are do nothing and do something. Do nothing alternative means the existing road conditions at the time of the study. Do something alternative consists of three traffic management scenarios: Alternative 1, changing traffic direction but not changing the existing one-way system; Alternative 2, applying a combination of one-way systems with two-way systems; and alternative 3, applying a condition of traffic management using two-way system in all roads. Whereas to evaluate network performance, the cost parameters of the trip, the average Volume Capacity Ratio (V/C), and the average speed are employed. The best policy alternative is Alternative 1 where the V/C value is 0.72, average speed of 27.57 km/hour, and cost of travel of IDR 9,370.87 million/hour.

Structural Effect of Using Steel Fiber Reinforcement on the Punching Shear of Self-Compacting Fiber Reinforced Concrete (SCFRC) Ribbed Slabs

—Ribbed slab is an ideal structure for architects and contractors. It has an attractive soffit appearance and also giving economical value when it is come in weight and material saving. Placing and finishing of concrete slab normally influence about 30% - 35% of overall cost of flooring system. Ribbed slab or also known as one-way joist slab system consist of regularly spaced concrete joist or ribs spanning in one direction, a reinforced concrete slab cast integrally with the ribs and beam span between the columns, perpendicular to the ribs. However the complexity of the structure itself has become an issue due to honeycomb and poor workmanship. To overcome this problem, the use of Self-Compacting Steel Fiber Reinforcement Concrete (SCFRC) could improve the workmanship quality and to minimize the occurrence of honeycomb in concrete. Steel fiber in concrete improved the resistance of reinforced structural members cracking, deflection and other serviceability condition. Thus, this alternative approach will be the main focus in this study.Punching shear strength in reinforced concrete slabs subjected to concentrated loads has received a lot of emphasis due to its importance in the structural system, this failure may take place due to in conservative design of slab overloading and deterioration of strength in concrete and reinforcement. The continuous improvement of the technology of SCFRC and the better knowledge on the mechanical behavior of this SCFRC ribbed slab are contributing to a larger field application of SCFRC. Determination of punching shear strength has received considerable attention by the engineering profession in recent years.

Added value of very high resolution climate simulations over South Korea using WRF modeling system

This study investigates the added value of very high resolution in long-term climate simulations over South Korea using the Weather Research and Forecasting (WRF) model. A one-way double-nested modeling system consisting of a mother domain (20-km resolution) and nested domain (5-km resolution) is customized for simulating the distinct climatological patterns in Korea, where the region-specific climate is largely influenced by the area’s complex geographical features. The ERA-Interim reanalysis data are used for the initial and boundary conditions, and the simulation spans the period from December 1, 1985 to December 31, 2005 (20-year analysis period with 1-month spin-up). Simulations from both the mother and the nested domain show reasonable performance in capturing the general characteristics of summer temperature and precipitation in terms of temporally and spatially averaged quantities. However, the added value from the nested domain with its higher resolution is apparently found in the reproduction of the intensity and frequency of extreme events and in the physical realism related to the partitioning of convective and large-scale precipitation. The nested domain not only better resolves the sharp gradients of temperature variation over short distances but also substantially reduces the systematic cold bias seen in temperature extremes produced by the mother domain. Furthermore, the nested domain is better able to simulate the upper tail of precipitation distributions and thus of extreme events. The higher resolution also improves the simulation of partitioning between convective and large-scale precipitation, leading to a plausible relationship between extreme precipitation and temperature and showing good agreement with in situ observation. Given the different behaviors of convective and large-scale precipitation in response to temperature changes, their realistic partitioning in the model has important potential for enhancing the reliability of precipitation projection under global warming.

Research on Mechanical Behaviour of High-rise Diagonal Grid Tube Structure and Case study

In order to obtain the mechanical characteristics of high-rise diagonal grid tube structure under horizontal and/or vertical loads, three types of structure model, which were diagonal grid tube structure, diagonal grid–frame tube and framed tube structure, were established by the finite element software Etabs. The laws of internal force distribution, interstory displacement, base shear and shear hysteresis effect, were analysed deeply. The results from three-model showed that compared with the framed tube structure, the diagonal grid tube structure had the larger stiffness and the shorter period. Under the horizontal seismic load, the total shear force of the diagonal grid tube structure improved 20% by that of the conventional framed tube structure, with the interlayer shear force and the interlayer displacement angle distribution keeping basically the same. The inclining column to the diagonal grid structure could enhance the lateral stiffness in its plane effectively, but hardly improve the lateral stiffness out of its plane. Then, the performance under the vertical load was also discussed. Under the action of the vertical load, the shear hysteresis effect appeared, especially for the flange inclined column. Subsequently, the feasibility of the diagonal grid tube in the engineering projects was evaluated. The finite element software ABAQUS was used to analyse the dynamic elastoplastic time history performance of a one-way oblique grid system high-rise building under rare earthquakes. The results showed that the maximum interlayer displacement of the structure was less than the limit of Chinese codes and standards, and the structure could achieve the goal of anti-seismic fortification without collapse under strong earthquakes. There was a conclusion that the diagonal grid tube could be applied as a part of the overall structure for high-rise or super-tall buildings in the zones with seismic design intensity of 7 degree.

Modelling of reactor pressure vessel subjected to pressurized thermal shock using 3D-XFEM

We describe the model developed for integrity assessment of a reactor pressure vessel (RPV) subjected to pressurized thermal shock (PTS). The assessment is based on a multi-step simulation scheme, which includes the thermo-hydraulic, thermo-mechanical and fracture mechanics analyses. The thermo-mechanical model uses the three-dimensional finite element method (FEM) to calculate the stress fields of the reactor pressure vessel (RPV) subjected to the thermal load and pressure during large break loss of coolant accident (LBLOCA). In this contribution, the multistep simulation scheme is extended to the analysis of two-phase steam-water flow occurring in the LBLOCA situation and the fracture analysis of postulated cracks under this accident event. It is demonstrated that the principle of the combined one-way coupled system code, CFD and structural mechanics codes can be used for the fracture analysis in case of a transient accident, which involves two-phase flow. The prediction of the temperature field is achieved by using two-phase computational fluid dynamics (CFD) simulation. To perform the stress analysis, an appropriate finite element discretization of the RPV wall is used, which considered the cladding and the ferritic low allow steel. The calculation of the stress intensity factor (SIF) in mode I for hypothetical cracks located in critical positions of the RPV is based on the linear elastic fracture mechanics (LEFM).The fracture mechanics model is based on the node-based submodeling technique in combination with XFEM in Abaqus. This is used to refine the mesh required by the fracture analysis in the region of interest, especially those regions under the cooling plume formed during the LBLOCA. The submodel may contain three types of cracks: axial, circumferential and inclined. The performed integrity assessment compares the stress intensity factor calculated in the deepest point of a surface crack with the material’s fracture toughness. Two approaches to extract the stress intensity factor were applied in the present paper, namely, the classical FEM and eXtended FEM or XFEM. The classical FEM and XFEM solutions are compared. Both techniques give similar results. However, XFEM is more convenient as it is mesh independent.

Fleet sizing for one-way electric carsharing services considering dynamic vehicle relocation and nonlinear charging profile

This study aims to determine the electric vehicle fleet size for one-way carsharing services by maximizing the profit of carsharing operators while taking into account the vehicle relocation operations and nonlinear electric vehicle charging profile. We formulate a set partitioning model for the considered problem. A tailored branch-and-price (B&P) approach is proposed to find the exact optimal solution of the model. In particular, an effective multi-label correcting method is developed to solve the pricing problem (i.e., generate columns) within the B&P approach. A novel non-dominated charging strategy is put up to avoid the exponential growth of labels caused by the allowance of partial charging with a nonlinear charging profile. In addition to the B&P approach, two heuristic methods are put forward for solving the large-scale problems or reinforcing the B&P approach. Numerical experiments with randomly generated instances and a case study based on a one-way carsharing operator in Singapore are conducted to further assess the efficiency and applicability of the proposed solution methods. The effects of several key parameters, i.e., the fixed cost of EV, relocation cost, electricity cost, service charge, EV driving range, the charging efficiency, and the number of rentals on the performance of a one-way electric carsharing system are also examined.

Jaringan Komunikasi Anak Jalanan Berkaitan dengan Diterapkannya Sistem Satu Arah di Kota Bogor

Abstract This research is a qualitative descriptive study that aims to determine the communication network of street children in connection with the implementation of a one-way system in the city of Bogor. It also finds out whether street children are one of the inhibiting factors in implementing a one-way system in the city of Bogor. The communication network described in this study is the structure of the wheeled communication network, the chain communication structure, the communication structure of the Y communication network, the circle network structure, and the communication network structure of all channels. Data sources used in this study are key informants, informants, events and activities, and literature related to group communication and communication networks. The sampling technique in this study was purposive sampling which was considered to know accurate information in response to the research problem formulation. Data collection techniques using in-depth interviews and observation techniques, while data analysis techniques used using interactive analysis models include: collection, data reduction, data interpretation, and drawing conclusions after verification. Based on the results of the study, communication networks are used by groups of children in the street that became the informant in this study. The first informants were from Tugu Kujang with chain communication network structure. The informants with wheel communication network structure are from Taman Topi, Lodaya, and Bantar Kemang. Street children are not directly inhibiting factors for the implementation of a one-way system in the city of Bogor, yet impeding aesthetics and the order of the city. The government conducts periodic training and provides a Work Training Center on a regular basis and provides Job Training Centers to reduce the growth rate of street children in Bogor city. Keywords: anak travel bogor, bogor city, communication network one-way system

Patients' and Doctors' Perceptions of a Mobile Phone-Based Consultation Service for Maternal, Neonatal, and Infant Health Care in Bangladesh: A Mixed-Methods Study.

BackgroundA mobile-based consultation service, or telehealth, can be used for remote consultations with health care professionals for screening, self-care management, and referral. In rural Bangladesh, where there is high demand for scarce male and even scarcer female doctors, remote consultations may help women seeking maternal and child health care. Aponjon is a mHealth service in Bangladesh that provides weekly voice or text messages to pregnant women, new mothers, and family members on various aspects of maternal, neonatal, and infant health. Subscribers can also access a dedicated 24*7 call center to discuss maternal, neonatal, and infant health or emergencies with medically trained doctors. The service provides advice, primary diagnoses, prescriptions, and referrals to subscriber callers.ObjectiveWe investigated the Aponjon service to understand access, acceptability, usability, benefits, and challenges of a mobile phone-based consultation service.MethodsWe conducted call log data analysis for September to November 2015 to understand how many unique subscribers accessed the service, who accessed the service, the geographical distribution of callers, and the purpose of the calls. We also conducted a qualitative exploratory substudy of eight married women and eight married men who were subscribers to and accessed the service during this time to understand their experiences. We interviewed 11 doctors from the same service who provided phone consultations to subscribers.ResultsApproximately 3894 unique subscribers accessed the service for single or multiple consultations during the study period; 68.36% (2662/3894) of subscribers were from rural households, and 53.00% (2064/3894) of calls were made by pregnant women or new mothers. Approximately 96.08% (5081/5288) calls were nonurgent, 2.69% (142/5288) semiurgent, and 1.23% (65/5288) urgent. Almost 64.7% (134/207) semiurgent or urgent calls came between 8 PM and 8 AM. Callers found the consultation service trustworthy, cost-effective, and convenient. The doctors dispelled misconceptions and promoted good health care practices, regular health check-ups, and responsible use of medicine. They helped families understand the severity of sicknesses and advised them to seek care at health facilities for semiurgent or urgent conditions. The service lacked a pro-poor policy to support talk times of subscribers from poor households and a proper referral system to help patients find the right care at the right facilities.ConclusionsAlthough a regular messaging service is constrained by a one-way communication system, this service using the same platform, gave subscribers access to an abbreviated “consultation” with medical doctors. The consultations provided subscribers with valued medical advice and support, although they were limited in their population reach and their integration into the wider medical system. Further research is required to understand the impact of advice and referral, cost-effectiveness, and willingness to pay for mHealth consultation services, but this research suggests that these services should be supported or even expanded.

Mixing hot and cold with sound

An acoustically forced fluid system is known to generate a time-averaged mean, or streaming, flow that evolves on a slow time scale compared to the acoustic-wave period. Classical acoustic streaming in a homogeneous fluid is typically associated with a one-way coupled system wherein the oscillatory acoustic fields inform the streaming mean flow, without any appreciable feedback. In contrast, Michel & Chini (J. Fluid Mech., vol. 858, 2019, pp. 536–564) investigate acoustic streaming in a stratified fluid and demonstrate that the streaming is sufficiently strong to induce significant rearrangements of the background temperature and density fields, resulting in a strong coupling between the acoustic waves and mean flow. This new class of streaming, referred to as baroclinic acoustic streaming, is shown to result in altered streaming patterns with enhanced heat transport that makes possible a range of new applications.

Microfabricaton of microfluidic check valves using comb-shaped moving plug for suppression of backflow in microchannel.

This study reports on an efficient microscale one-way valve system that combines the physical properties of photopolymerized microstructures and viscoelastic microchannels to rectify flows with low Reynolds numbers. The comb-shaped moving plug in the microchannel prevented backflow in the closed state to ensure that the microchannel remained completely blocked in the closed state, but allowed forward flow in the open state. This microfluidic check valve was microfabricated using the combination of the soft lithography and the releasing methods with the use of a double photoresist layer to create microchannels and free-moving comb-shaped microstructures, respectively. As a result, the microfluidic check valves elicited average high-pressure differences as much as 10.75kPa between the backward and forward flows at low Reynolds numbers of the order of 0.253, thus demonstrating efficient rectification of microfluids. This study supports the use of rectification systems for the development of biomedical devices, such as drug delivery, micropumps, and lab-on-a-chip, by allowing unidirectional flow.

On outage minimization in RF energy harvesting relay assisted bidirectional communication

This paper explores an end-to-end outage probability experienced in a bidirectional relay assisted communication where the relay is assumed to be equipped with an RF energy harvesting circuit. First, the closed-form expression for the outage of the system is derived. This is followed by the formulation of an unconstrained optimization problem to achieve minimum outage probability with respect to the relay placement and consequent time allocation for energy harvesting. The system model is further extended in an underlay cognitive radio framework to study the impact of a primary user outage constraint on the end-to-end outage performance of the two-way communications. The accuracy of analytical results is validated through simulation results. The impact of various system parameters like relay position, time allocation factor, target rate of transmission on the outage probability is also observed. In addition, it is also shown that spectral efficiency of the communication system using hybrid power-time switching relaying protocol is much superior to similar one-way and two-way relay assisted communication system with power splitting relaying protocol.

Foundation and performance evaluation of real-time GNSS high-precision one-way timing system

Global navigation satellite system (GNSS) can realize global time synchronization with tens of nanoseconds precision. For more precise time synchronization applications, two-way satellite time and frequency transfer is commonly used despite its high cost and requiring a geostationary satellite. Considering the high cost, people started to use the GNSS signals to realize high accuracy time transfer, named common-view or all-in-view, which can achieve several nanoseconds according to the analyses and verifications of previous studies. However, time transfer cannot realize real-time timing in a large area as a common GNSS one-way timing receiver does. In such a timing system, a highly stable reference and a matched high-precision timing receiver system are necessary. To solve this problem, we have established a one-way timing system based on a ground-based augmentation system. The system estimates real-time high-precision satellite clocks using the ground-based augmentation network as the time reference. Moreover, the time reference is transferred to the terminal through real-time precise point positioning (PPP). Finally, the timing receiver synchronizes its local clock to the reference by real-time clock adjustment, resulting in high-precision timing. We present the details of this system, including the time reference, the PPP algorithm, and the timing receiver technologies. Finally, we give the precision and stability evaluation of the whole system, especially for one pulse per second (1 PPS) outputs of the terminal. The results show that the stability of the 1 PPS output is better than 1 ns in a day.