bluuebunny/crossref_metadata_2025 huggingface dataset:
Competition and Sustainability Development of a Multi-Airport Region: A Case Study of the Guangdong–Hong Kong–Macao Greater Bay Area
Authors: Liao Wang , Cao Xiaoshu , Li Shengchao
Published: May 2019

A new era in the development of multi-airport regions (MARs) has been in China, especially in the construction of global urban areas such as the Guangdong–Hong Kong–Macao Greater Bay Area (GBA). In order to better understand competition and provide significant advice to support sustainable development of Chinese MARs, this paper takes the GBA-MAR as an example, and then explores the competition between airports in this multi-airport region based on route level and its impact on passenger airport choice using three liner models. According to our findings, competition is concentrated on a few air routes in the Northeast–East Coastal region and the Asia-Pacific region, in which all three airports operate. Although the domestic market of the GBA-MAR has been relatively mature, the international air transport market is still left with considerable room, which is also reflected in connections to the world’s cities and tourist destinations. In addition, the research also found that different airport brands created by route type significantly affected passenger airport choice. Overall, the study revealed that whether from a supply or demand aspect, competition between airports in a multi-airport region—not just airline competition in a single airport—is an important topic.
The Ecological Criteria of Circular Growth and the Rebound Risk of Closed Loops
Authors: Horvath Balint , Bahna Miriam , Fogarassy Csaba
Published: May 2019

The implementation practices of the circular economy (CE) put a strong emphasis on preventing material losses in economic processes. The general interpretation of the concept focuses on closing technological and biological cycles by reintegrating end-of-life products into production and consumption systems. Thus, “closed loops” have become a trademark of circular transition. However, this limited perception fails to cover the essence of the CE. Besides closure, the utility of material loops can be prolonged, and a conscious consumer attitude may even prevent the creation of unnecessary material flows. This paper aims at proving that the preference of closed loops would result in deadweight losses in the long run. The conducted analysis ranks EU member states according to the most anticipated material flow indicators. Then, the study presents a new methodology to measure circular efficiency based on the available ecological capacity of the countries. The outcomes show that the poorly performing actors are in fact not far from a sustainable operation. Meanwhile, the countries with the most efficient material flow values present the widest development gap to reach the ideal level of circularity.
Engaging Employees with Good Sustainability: Key Performance Indicators for Dry Ports
Authors: Hui Felix Kin Peng , Aye Lu , Duffield Colin F.
Published: May 2019

Dry ports have the potential to enhance the sustainability of transport systems, yet their introduction requires major changes to the current logistics chain. Further, emphasising sustainability goals and continued employee engagement can be a challenge when developing or implementing organisational change management programs in dry ports. Key considerations include governmental requirements and compliance, investor expectations, as well as employee engagement; these factors may be conflicting. The top-down management approach supported by strong leadership, participative approaches and constant communication assists in achieving successful change management. Sound selection of key performance indicators (KPIs) provides a set of metrics to track and aid the change process. They serve as a unifying link between top managements’ sustainability goals and employees’ engagement. The initial findings of our research confirm that both port and terminal operators have a gap in their understanding of the importance of sustainability goals and environmental goals. This will have a flow-on effect of port and terminal operators not driving the right messages to their staff in their organisational change management programs. Based on a critical literature review, it has been established what might qualify as good sustainability KPIs for dry ports. An example of a dry port at the Port of Somerton has been included. As every dry port has different requirements and constraints, it is important to develop KPIs together with stakeholders.
Usage of Recycled Technical Textiles as Thermal Insulation and an Acoustic Absorber
Authors: Danihelová Anna , Němec Miroslav , Gergeľ Tomáš , Gejdoš Miloš , Gordanová Janka , Sčensný Patrik
Published: May 2019

The sound absorption coefficient is a commonly used parameter to characterize the acoustic properties of materials. The fire performance of construction products has to be evaluated on the basis of their reaction to fire performance. The evaluation of the reaction to fire performance for the flammable construction materials which are in Class E reaction to fire is based on the ignitability test and the thermal test using the radiant heat source. For this study, nine types of STERED® products, which were made from the recycled automotive technical textiles, were chosen in order to evaluate their ability for sound absorption and the reaction to fire. The fire performance was evaluated on the basis of the relative mass loss in the radiant heat source test; the ignitability in accordance with ISO 11925-2, the possible appearance of flame, duration of flame, and the glowing during the single flame source test. The sound absorption of nine products was rated on the basis of the sound absorption coefficient and the noise reduction coefficient. The measurement was performed using the transfer function method in accordance with ISO 10534-2. From the nine tested types of STERED® products, the product Senizol AT XX2 TL 60 had the lowest mass loss at thermal loads up to 700 °C and it fulfilled the conditions for Class E reaction to fire. This product had the highest noise reduction coefficient of 0.81 and a high absorption coefficient for frequencies ranging between 500 Hz and 2000 Hz. The STERED® product Senizol AT XX2 TL 60, as well as Senizol AT 22 TL 50, Senizol AT 40 TL 25, Senizol AT XX4 TL 50 and Senizol AT XX4 TL 10 with a sound absorption coefficient α of between 0.80 to 0.95 and corresponding NRCs from 0.66 to 0.81, these STERED® products can be classified according to ISO 11654 into the sound absorption classes A and B.
An Efficient Burst Detection and Isolation Monitoring System for Water Distribution Networks Using Multivariate Statistical Techniques
Authors: Nam KiJeon , Ifaei Pouya , Heo Sungku , Rhee Gahee , Lee Seungchul , Yoo ChangKyoo
Published: May 2019

Detection and isolation of burst locations in water distribution networks (WDN) are challenging problems in urban management because burst events cause considerable economic, social, and environmental losses. In the present study, a novel monitoring and sensor placement approach is proposed for rapid and robust burst detection. Accordingly, a hybrid principal component analysis (PCA) and standardized exponential weighted moving average (EWMA) system is proposed for WDN monitoring and management. In addition, the optimal sensor configuration is obtained using PCA, k-means clustering, and a sensitivity analysis considering the diurnal patterns and the noises of pressure and flowrate data in the WDN. The proposed system is applied to a branched WDN, and the results are compared to those obtained with conventional monitoring systems. The results show that the proposed system detected the burst occurrence regardless of noise size with a detection rate of 93%. Compared to conventional systems, the isolation ratio improved by 10%, indicating that the bursts were isolated more accurately. In addition, the corresponding sensor configuration was 40% less expensive than the conventional systems.
Urban Expansion in Ethiopia from 1987 to 2017: Characteristics, Spatial Patterns, and Driving Forces
Authors: Terfa Berhanu Keno , Chen Nengcheng , Liu Dandan , Zhang Xiang , Niyogi Dev
Published: May 2019

Rapid urban growth in major cities of a country poses challenges for sustainable development. Particularly in Africa, the process of rapid urbanization is little understood and research is mostly limited to single cities. Thus, this study provides a comprehensive comparative analysis of the growth and spatial patterns of urban development in the three major cities of Ethiopia (Addis Ababa, Adama, and Hawassa) from 1987 to 2017. Also, the applicability of diffusion and coalescence theory on the evolution of these cities has been tested. Remote sensing and GIS technologies were combined with spatial metrics and morphological analysis was employed to undertake this study. The result revealed that all the studied cities experienced accelerated growth in the urbanized areas, but the cities with a larger initial urbanized size were associated with lower expansion rates. Differences in extent and direction of expansion in each city were mostly related to physical features, urban master plans, and policies, with an increase in the irregularity and dispersion of urban growth, representing strong evidence of urban sprawl. The spatiotemporal analysis confirmed that the urbanization processes of Addis Ababa and Adama were consistent and Hawassa city diverged from expectations based on diffusion and coalescence theory. In general, large cities with strong economic growth in a country fail to effectively control the scattered nature of urban growth, thus requiring aggressive policy intervention. The approach used in this study permits a deeper exploration of urban development patterns and the identification of priority areas for effective urban planning and management.
Ellipse Coefficient Map-Based Geomagnetic Fingerprint Considering Azimuth Angles
Authors: Seong Ju-Hyeon , Lee Seung-Hyun , Yoon Kyoung-Kuk , Seo Dong-Hoan
Published: May 2019

Geomagnetic fingerprint has been actively studied because of the high signal stability and positioning resolution even when the time has elapsed. However, since the measured three-axis geomagnetism signals at one position are irregular according to the change of the azimuth angle, a large-sized database which is stored magnitudes per angles is required for robust and accurate positioning against the change of the azimuth angle. To solve this problem, this paper proposes a novel approach, an elliptic coefficient map based geomagnetic fingerprint. Unlike the general fingerprint, which stores strength or magnitude of the geomagnetism signals depending on the position, the proposed algorithm minimized the size of databased by storing the Ellipse coefficient map through the ellipse equation derived from the characteristics of 2-D magnetic vectors depending on the position. In addition, the curvature bias of ellipse was reduced by applying the normalized linear least-squares method to 2-D geomagnetic characteristics and the positioning accuracy was improved by applying the weighted geomagnetic signal equalization method.
Discovery of a Potential Human Serum Biomarker for Chronic Seafood Toxin Exposure Using an SPR Biosensor
Authors: Lefebvre Kathi A. , Yakes Betsy Jean , Frame Elizabeth , Kendrick Preston , Shum Sara , Isoherranen Nina , Ferriss Bridget E. , Robertson Alison , Hendrix Alicia , Marcinek David J. , Grattan Lynn
Published: May 2019

Domoic acid (DA)-producing harmful algal blooms (HABs) have been present at unprecedented geographic extent and duration in recent years causing an increase in contamination of seafood by this common environmental neurotoxin. The toxin is responsible for the neurotoxic illness, amnesic shellfish poisoning (ASP), that is characterized by gastro-intestinal distress, seizures, memory loss, and death. Established seafood safety regulatory limits of 20 μg DA/g shellfish have been relatively successful at protecting human seafood consumers from short-term high-level exposures and episodes of acute ASP. Significant concerns, however, remain regarding the potential impact of repetitive low-level or chronic DA exposure for which there are no protections. Here, we report the novel discovery of a DA-specific antibody in the serum of chronically-exposed tribal shellfish harvesters from a region where DA is commonly detected at low levels in razor clams year-round. The toxin was also detected in tribal shellfish consumers’ urine samples confirming systemic DA exposure via consumption of legally-harvested razor clams. The presence of a DA-specific antibody in the serum of human shellfish consumers confirms long-term chronic DA exposure and may be useful as a diagnostic biomarker in a clinical setting. Adverse effects of chronic low-level DA exposure have been previously documented in laboratory animal studies and tribal razor clam consumers, underscoring the potential clinical impact of such a diagnostic biomarker for protecting human health. The discovery of this type of antibody response to chronic DA exposure has broader implications for other environmental neurotoxins of concern.
Latent Tuberculosis Infection among Healthcare Workers in Duhok Province: From Screening to Prophylactic Treatment
Authors: Almufty Hind Bahzad , Abdulrahman Ibtesam Salih , Merza Muayad Aghali
Published: May 2019

Healthcare workers (HCWs) are at increased risk of infection with Mycobacterium tuberculosis (Mtb) and, hence, of developing tuberculosis (TB) disease. The aims of this study are to identify the prevalence and determinants of latent TB infection (LTBI) among HCWs in Duhok Province. This is a cross-sectional prospective study conducted during April–July 2018 in different health care facilities of Duhok province. HCWs at multiple levels were selected by a non-systematic random sampling method. Information on demographic and associated risk factors of LTBI were collected by using a standardized questionnaire. Thereafter, all HCWs underwent QuantiFERON Gold Plus (QFT-Plus) assay. HCWs with indeterminate QFT-Plus underwent a Tuberculin Skin Test. HCWs with positive results were further evaluated by smear microscopy investigation and chest X-ray examination. Three hundred ninety-five HCWs were enrolled; 49 (12%) tested positive for LTBI. The mean age of the HCWs was 33.4 ± 9.25 with a female predominance (51.1%). According to the univariate analysis, LTBI was significantly higher among HCWs with the following: age groups ≥ 30 years, alcohol intake, ≥ 11 years of employment, high risk stratification workplaces, and medical doctors. In the multivariate analysis, the age group of 30–39 years (OR = 0.288, 95% CI: 0.105–0.794, p value = 0.016) was the only risk factor associated with LTBI. Further medical investigations did not reveal active TB cases among HCWs with LTBI. With regards to prophylactic treatment, 31 (63.3%) LTBI HCWs accepted the treatment, whereas 18 (36.7%) declined the chemoprophylaxis. Of these 31 HCWs on chemoprophylaxis, 12 (38.7%) received isoniazid (INH) for six months, 17 (54.8%) received INH in combination with rifampicin (RMP) for three months, and two (6.5%) received alternative therapy because of anti-TB drug intolerance. In conclusions, although Iraq is a relatively high TB burden country, the prevalence of LTBI among Duhok HCWs is relatively low. It is important to screen HCWs in Duhok for LTBI, particularly medical doctors, young adults, alcoholics, and those whom had a long duration of employment in high-risk workplaces. The acceptance rate of HCWs with LTBI to chemoprophylaxis was low. Therefore, ensuring medical efforts to educate the healthcare staff particularly, non-professionals are a priority to encourage chemoprophylaxis acceptance.
Novel Synthetic DNA Immunogens Targeting Latent Expressed Antigens of Epstein–Barr Virus Elicit Potent Cellular Responses and Inhibit Tumor Growth
Authors: Wojtak Krzysztof , Perales-Puchalt Alfredo , Weiner David B.
Published: May 2019

Infectious diseases are linked to 15%–20% of cancers worldwide. Among them, Epstein–Barr virus (EBV) is an oncogenic herpesvirus that chronically infects over 90% of the adult population, with over 200,000 cases of cancer and 150,000 cancer-related deaths attributed to it yearly. Acute EBV infection can present as infectious mononucleosis, and lead to the future onset of multiple cancers, including Burkitt lymphoma, Hodgkin lymphoma, nasopharyngeal carcinoma, and gastric carcinoma. Many of these cancers express latent viral genes, including Epstein–Barr virus nuclear antigen 1 (EBNA1) and latent membrane proteins 1 and 2 (LMP1 and LMP2). Previous attempts to create potent immunogens against EBV have been reported but generated mixed success. We designed novel Synthetic Consensus (SynCon) DNA vaccines against EBNA1, LMP1 and LMP2 to improve on the immune potency targeting important antigens expressed in latently infected cells. These EBV tumor antigens are hypothesized to be useful targets for potential immunotherapy of EBV-driven cancers. We optimized the genetic sequences for these three antigens, studied them for expression, and examined their immune profiles in vivo. We observed that these immunogens generated unique profiles based on which antigen was delivered as the vaccine target. EBNA1vax and LMP2Avax generated the most robust T cell immunity. Interestingly, LMP1vax was a very weak immunogen, generating very low levels of CD8 T cell immunity both as a standalone vaccine and as part of a trivalent vaccine cocktail. LMP2Avax was able to drive immunity that impacted EBV-antigen-positive tumor growth. These studies suggest that engineered EBV latent protein vaccines deserve additional study as potential agents for immunotherapy of EBV-driven cancers.
Progress in Water Footprint Assessment: Towards Collective Action in Water Governance
Authors: Hoekstra Arjen Y. , Chapagain Ashok K. , van Oel Pieter R.
Published: May 2019

We introduce ten studies in the field of water footprint assessment (WFA) that are representative of the type of papers currently being published in this broad interdisciplinary field. WFA is the study of freshwater use, scarcity, and pollution in relation to consumption, production, and trade patterns. The reliable availability of sufficient and clean water is critical in sustaining the supply of food, energy, and various manufactured goods. Collective and coordinated action at different levels and along all stages of commodity supply chains is necessary to bring about more sustainable, efficient, and equitable water use. In order to position the papers of this volume, we introduce a spectrum for collective action that can give insight in the various ways different actors can contribute to the reduction of the water footprint of human activities. The papers cover different niches in this large spectrum, focusing on different scales of governance and different stages in the supply chain of products. As for future research, we conclude that more research is needed on how actions at different spatial levels and how the different players along supply chains can create the best synergies to make the water footprint of our production and consumption patterns more sustainable.
Exploring Explicit Delay Time for Volume Compensation in Feedforward Control of Canal Systems
Authors: Liao Wenjun , Guan Guanghua , Tian Xin
Published: May 2019

In the open channel control algorithm, good feed-forward controllers will reduce the transition time of the canal and improve performance. Feedforward control algorithms based on active storage compensation are greatly affected by delay time. However, there is no literature comparing the three most commonly used algorithms, namely volume step compensation, dynamic wave principle and water balance models, under the operation mode of constant water level downstream. In order to compare the existing three algorithms, and to avoid storage calculation by calculating the constant non-uniform water surface line or identification of relevant parameters, combined with the open channel constant gradient flow theory with the storage compensation algorithm, a delay time explicit algorithm is proposed in this study. Tested on the first canal pool of the American Society of Civil Engineers (ASCE) Test Canal 2, the performance of the delay time explicit algorithm is assessed and compared to that of the three conventional algorithms. In the current water intake plan, i.e., in the second hour, the intake begins to take 1.2 m3/s, and the upstream flow of the canal pool changes from 6 m3/s to 7.2 m3/s, among the three existing algorithms, the volume step compensation algorithm has better performance in terms of time to achieve stability, i.e., 1.25 h. The actual adjusted storage accounts for 99.6% of the target adjusted storage, which can basically meet the requirement of compensated storage of the canal pool. The delay time explicit algorithm only needs 1.47 h to stabilize the regulation system. The fluctuation of water level and discharge in the regulation process is small. The actual adjusted storage accounts for 99.6% of the target adjusted storage, which can basically meet the requirement of compensated storage for the canal pool. The delay time calculated by explicit algorithm can provide references for the determination of delay time in feedforward control.
Clogging of Infiltration Basin and Its Impact on Suspended Particles Transport in Unconfined Sand Aquifer: Insights from a Laboratory Study
Authors: Zou Zhike , Shu Longcang , Min Xing , Chifuniro Mabedi Esther
Published: May 2019

A laboratory study was undertaken to investigate the physical clogging of a sand medium by injecting suspended particles (SP), with diameters ranging from 0.03 to 63.41 μm, into an infiltration basin, which was installed in a sand tank under the condition of constant head. The hydraulic conductivity (K) of the saturated porous medium was found to have decreased by 27% because of re-arrangement over the seven days of self-filtration. A clogging layer was observed on the infiltration basin bottom, probably due to straining over the stormwater infiltration stage. Particle-size analyses also indicate that retention of bigger SP led to faster straining of smaller SP, despite the small fraction of bigger SP. The clogging layer weakened the hydraulic connection between the water level in the basin and the water table of the unconfined aquifer until nearly no water could infiltrate into the aquifer. The deposition of finer SP that entered into the aquifer are governed by the hydrodynamic forces. These finer SP caused non-uniform permeability reduction of the porous medium, with an estimated 35% of permeability reduction occurring beneath the infiltration basin. However, the reduction appears to be reversible, as the fine SP deposited on the pore surfaces of the porous medium can be released or detached by the continuous horizontal hydraulic gradient. Extended tailing of the outlet breakthrough curve (BTC) also strongly supported the detachment of SP. This study focused on the effects of particles’ polydispersity and hydrodynamic forces on the hydraulic characteristics of the porous medium.
Impact Assessment of Future Climate Change on Streamflows Upstream of Khanpur Dam, Pakistan using Soil and Water Assessment Tool
Authors: Nauman Saima , Zulkafli Zed , Bin Ghazali Abdul Halim , Yusuf Badronnisa
Published: May 2019

The study aims to evaluate the long-term changes in meteorological parameters and to quantify their impacts on water resources of the Haro River watershed located on the upstream side of Khanpur Dam in Pakistan. The climate data was obtained from the NASA Earth Exchange Global Daily Downscaled Projection (NEX-GDDP) for MIROC-ESM model under two Representative Concentration Pathway (RCP) scenarios. The model data was bias corrected and the performance of the bias correction was assessed statistically. Soil and Water Assessment Tool was used for the hydrological simulation of watershed followed by model calibration using Sequential Uncertainty Fitting version-2. The study is useful for devising strategies for future management of Khanpur Dam. The study indicated that in the future, at Murree station (P-1), the maximum temperature, minimum temperature and precipitation were anticipated to increase from 3.1 °C (RCP 4.5) to 4.0 °C (RCP 8.5), 3.2 °C (RCP 4.5) to 4.3 °C (RCP 8.5) and 8.6% to 13.5% respectively, in comparison to the baseline period. Similarly, at Islamabad station (P-2), the maximum temperature, minimum temperature and precipitation were projected to increase from 3.3 °C (RCP 4.5) to 4.1 °C (RCP 8.5), 3.3 °C (RCP 4.5) to 4.2 °C (RCP 8.5) and 14.0% to 21.2% respectively compared to baseline period. The streamflows at Haro River basin were expected to rise from 8.7 m3/s to 9.3 m3/s.
Achieving Urban Stormwater Mitigation Goals on Different Land Parcels with a Capacity Trading Approach
Authors: Xu Qing , Jia Zhonghua , Tang Shuangcheng , Luo Wan , Xu Chengxuan
Published: May 2019

Building Green Infrastructures (GIs) to reduce stormwater runoff has been recognized as an effective approach to mitigate the negative impact of urban sprawl. Due to the significant differences in urban land use, some Land Parcels (LPs) may have difficulty in building enough GIs to meet stormwater mitigation goals. In this paper, we proposed a Capacity Trading (CT) approach that allows some LPs to trade their extra runoff retention capacities with LPs that have building difficulties, so that they can jointly reach the overall mitigation goal together. The rationale behind CT is that, to avoid potential penalties, it may be more economical for some LPs to ‘buy’ credit rather than to ‘build’ GIs. A case study was used to demonstrate CT operations for two trading scales: (1) CT within neighboring LPs (i.e., CT-1), and (2) CT within 20 m-radius LPs (i.e., CT-2). A GI implementation baseline intensity was set up firstly by treating the whole study area as one entity to reach a specified stormwater runoff control target; individual LPs were then examined for their GI building capacities, which may be deficit or surplus against the target. Results showed that the number and area of deficit LPs were reduced significantly through either CT scales; the number of deficit LPs was reduced from 139 to 97 with CT-1 and 78 with CT-2, and the deficit area was reduced from 649 ha to 558 with CT-1 and 478 ha with CT-2, respectively. The proposed method assumes LPs as the basic planning unit and encourages some stakeholders to maximize their GI building potential to compensate for those with disadvantages. The economic incentives for conducting CT among different LPs in urban area can help achieve stormwater mitigation goals more economically and flexibly. Some coordination among LPs in GI implementation is necessary, which presents both opportunities and challenges for city management.
Features of digital control of flywheel engine, jsc corporation vniiem for high-dynamic spacecraft
Authors: Babishin Vladimir D. , Dementyev Dmitriy Yu. , Mikhailov Mikhail A. , Nekrasov Vladimir V. , Sobolev Dmitriy Yu. , Sosedko Kseniya A.
Published: May 2019

The development of radiation-resistant microcontroller technology opened new possibilities for controlling the flywheel engine and, consequently, the whole spacecraft. The lack of import-independent flywheel engine having the advanced capabilities as compared with domestic and foreign analogs made it necessary to develop a new generation of flywheel engines with digital microcontroller-based control at JSC Corporation VNIIEM. Such a flywheel engine is being developed as a fast-acting actuator of the orientation and stabilization system of a high-dynamic spacecraft (the maximum control moment of the new flywheel engine is 1 N·m).
Such features of creating digital microcontroller-based control of a new flywheel engine as organizing the flywheel engine rotor rate feedback, consideration of the basic control modes of the flywheel engine and options for reaching the required rotor rate of the flywheel engine, as well as self-diagnostics not only controlling but automatically updating the diagnosed parameters of the flywheel engine are given in this article.
Key words: flywheel engine, digital control, microcontroller-based control, JSC Corporation VNIIEM.
Techniques for iterative static analysis of a quad-orifice electrohydraulic steering actuator of rocket stages
Authors: Belonogov Oleg B.
Published: May 2019

The paper contains results of development and study of iterative techniques for static anal-ysis of quad-orifice electrohydraulic steering engine, namely, techniques for calculating its static characteristics (force and velocity characteristics) taking into account parameters of local hydraulic resistance parameters, making it possible to do analysis at various values of power supply voltage and temperature. The proposed techniques are based on solving systems of non-linear algebraic and transcendental equations of math models of the steering actuator describing its static operational modes. Taken as a basis for development of techniques for static analysis of the steering actuator are methods of integrated simulation of physical properties of working fluids of steering actuators and hydraulic drives, iterative methods for calculating parameters of working fluids flow in connecting lines, channels, flow-through elements and valves, results of studies of operating processes for steering actuator constituent elements, as well as a modification of the Seidel method for solving a system of non-linear algebraic and transcendental equations. The paper provides the results of testing the developed static analysis iterative techniques of such a steering actuator.
Key words: static analysis, electrohydraulic steering actuator, non-linear algebraic and transcendent equations
Analysis and calculation of the process of low-pressure reverse osmosis during recycling of hygienic water
Authors: Bobe Leonid S. , Salnikov Nikolay A.
Published: May 2019

Analysis and calculation have been conducted of the process of low-pressure reverse osmosis in the membrane apparatus of the system for recycling hygiene water for the space station. The paper describes the physics of the reverse osmosis treatment and determines the motive force of the process, which is the difference of effective pressures (operating pressure minus osmotic pressure) in the solution near the surface of the membrane and in the purified water. It is demonstrated that the membrane scrubbing action is accompanied by diffusion outflow of the cleaning agent components away from the membrane. The mass transfer coefficient and the difference of concentrations (and, accordingly, the difference of osmotic pressures) in the boundary layer of the pressure channel can be determined using an extended analogy between mass transfer and heat transfer. A procedure has been proposed and proven in an experiment for calculating the throughput of a reverse osmosis apparatus purifying the hygiene water obtained through the use of a cleaning agent used in sanitation and housekeeping procedures on Earth.
Key words: life support system, hygiene water, water processing, low-pressure reverse osmosis, space station.
Choice of energy accumulator parameters for a new peripheral docking mechanism
Authors: Yaskevich Andrey V. , Chernyshev Ivan Ye.
Published: May 2019

Spacecraft docking is a controlled on-orbit mechanical assembly process realized using active and passive docking units. The docking mechanism of the active unit provides capture conditions, attenuation of active spacecraft approach energy, alignment and retraction of the docking units before their hard connection. A kinematical scheme of a new peripheral docking mechanism is considered in this paper. Instead of energy damping, it is based on energy accumulation using springs with controlled recoil blocking. The blocking is activated before docking and keeps the docking mechanism in its initial position. On the first contact signal, the blocking is switched off releasing the energy of compressed springs for quick forward moving of the docking ring and improving capture. The blocking is activated again after capture and approach energy is accumulated by the springs without returning to the mechanical system. Avoiding contacts of docking mechanism links between each other and with the docking unit body is important for peripheral mechanisms due to their design. A procedure for choosing parameters of an energy accumulator that allows attenuating a max permissible energy without link contacts and without exceeding the max permissible value of the axial interface load is considered here.
Key words: spacecraft, docking, docking mechanism.
A study into the feasibility of using the oxygen-hydrocarbon engine 11D58M as a basis for development of a high-performance multifunctional gas-generatorless rocket engine with oxygen cooling
Authors: Sokolov Boris A. , Tupitsyn Nikolay N.
Published: May 2019

The paper presents results of engineering studies and research and development efforts at RSC Energia to analyze and prove the feasibility of using the mass-produced oxygen-hydrocarbon engine 11D58M with 8.5 ton-force thrust as a basis for development of a high-performance multifunctional rocket engine with oxygen cooling and 5 ton-force thrust, which is optimal for upper stages (US), embodying a system that does not include a gas generator.
The multi-functionality of the engine implies including in it additional units supporting some functions that are important for US, such as feeding propellant from US tanks to the engine after flying in zero gravity, autonomous control of the engine automatic equipment to support its firing, shutdown, adjustments during burn and emergency protection in case of off-nominal operation, as well as generating torques for controlling the US attitude and stabilizing it during coasting, etc.
Replacing conventional engine chamber cooling that uses high-boiling hydrocarbon fuel with the innovative oxygen cooling makes it possible to get rid of the internal film cooling circuits and eliminate their attendant losses of fuel, while the use of the oxygen gasified in the cooling circuit of the chamber to drive the turbo pump assembly permits to design an engine that does not have a gas generator.
Key words: Multifunctional rocket engine, oxygen cooling, gas-generatorless design, upper stage.
INFLUENCIA DE SOFTWARE EDUCATIVO EN LA CONSOLIDACIÓN DEL SISTEMA DE NUMERACIÓN POSICIONAL
Authors: Acosta Minoli César A. , Hoyos Salcedo Efraín A. , Restrepo Álape Leonardo D.
Published: May 2019

Este trabajo presenta una propuesta de enseñanza apoyada en material didáctico manipulativo y computarizado para la consolidación del sistema de numeración posicional en base diez a partir de la lógica de los sistemas posicionales. Se estableció experimental y cualitativamente los efectos del uso de la propuesta en la consolidación conceptual del sistema de numeración posicional. Es de resaltar el diseño y desarrollo de un software educativo por parte de los investigadores, considerando una serie de elementos didácticos y teóricos para facilitar en principio, la consolidación de los sistemas de numeración posicional. El estudio permitió evidenciar que una metodología de enseñanza enriquecida con materiales manipulativos y computarizados se presenta como una importante herramienta didáctica en la enseñanza y en la consolidación de los sistemas posicionales de numeración.
DETECCIÓN DE POSES DE LAS MANOS USANDO DESCRIPTORES LBP
Authors: Torres Arboleda Cristhian , Iregui Guerrero Marcela
Published: May 2019

El reconocimiento de gestos se ha presentado como una alternativa para la implementación de sistemas de interacción eficaces. Particularmente las aplicaciones basadas en visión artificial poseen ventajas en portabilidad frente a otras alternativas. Sin embargo, los algoritmos suelen requerir entrenamiento computacional intensivo, siendo difíciles de implementar en dispositivos móviles. En este artículo se realiza un estudio preliminar para la detección de poses de la mano usando un algoritmo basado en Patrones Binarios locales, más conocido por su sigla en inglés LBP (Local Binary Patterns). Para lo anterior, se presenta un modelo heurístico de división de la mano en regiones ponderadas diferencialmente, que permite la clasificación directa de los gestos usando una medida de similitud. Los pesos y la distribución de regiones se evaluaron de acuerdo a su precisión en la clasificación de cada pose de la mano. Estas pruebas se realizaron en un conjunto de imágenes, capturadas en condiciones controladas, correspondientes a cinco poses diferentes. El algoritmo propuesto con el esquema de regiones ponderadas muestra una buena capacidad de discriminación y presenta una alternativa válida para futuras aplicaciones.
DETECCIÓN DE CAMBIOS NO SUPERVISADA DE IMÁGENES SAR PARA EL SEGUIMIENTO DEL COMPORTAMIENTO Y ANÁLISIS DE INUNDACIONES EN COLOMBIA
Authors: Avendaño P Jonathan , Padilla Jorge I. , Vera Jhon E. , Parra Jaime A.
Published: May 2019

Este trabajo propone un método no supervisado de detección cambios para el estudio del comportamiento de las inundaciones en Colombia usando imágenes SAR (Synthetic Aperture Radar). El enfoque de detección de cambios propuesto es un método pre-Clasificación, en el cual se clasifican primero las imágenes y luego por medio de operadores de relación se encuentra los cambios. En primera instancia se filtraron las imágenes SAR con el filtro Frost-Mejorado con el objetivo de eliminar el efecto del ruido Speckle. Para la segmentación no supervisada de imágenes SAR se utilizaron los enfoques de Fuzzy-Clustering (FCM)  y k-means,  los resultados  de ambos enfoques fueron fusionados con el fin de mejorar la precisión en la segmentación usando el método  de fusión de imágenes PCA (Principal Component Analysis). Para la detección de cambios se implementaron los operadores de relación Mean-Ratio y Log-Ratio, los resultados de ambos operadores de relación también fueron fusionados usando PCA con el fin de mejorar la precisión en esta fase del método propuesto. Para la experimentación se usaron en primera instancia imágenes sintéticas creadas a partir de zonas homogéneas de imágenes SAR de Colombia. Con estas imágenes fue posible evaluar el desempeño del método propuesto. Los resultados mostraron una precisión total alrededor del 99 %, lo que concluye que el método propuesto es altamente eficiente sobre el conjunto de datos usado. Luego se experimentó sobre dos imágenes SAR reales, una antes y otra después de una inundación, las cuales fueron proporcionadas por el IDEAM y cubren el área del Magdalena bajo en el municipio del Plato-Magdalena. El método propuesto encontró que en estas imágenes aproximadamente 77.46 hectáreas del municipio del Plato- Magdalena fueron inundadas por el río Magdalena.
LA GESTIÓN EN LOS PLANES INTEGRALES SISO EN EL SECTOR DE LA CONSTRUCCIÓN
Authors: Duque Arango John Jairo
Published: May 2019

El documento hace referencia al grado gestión de los planes SISO por parte de la empresas del sector de la construcción, trabajo de investigación que permite determinar la aplicabilidad de los diversos programas que conforman el plan integral. La metodología utilizada como herramienta un software en java que de manera porcentual evalúa el grado de ejecución de cada una de los programas y sugiere los correctivos del caso. Los resultados obtenidos determinan el diagnóstico actual del sector y permiten el diseño de una guía de control que contiene una serie de actividades acordes al proceso constructivo. Las conclusiones abordan los aspectos de importancia del trabajo y propone una serie de recomendaciones a tener en cuenta en futuros proyectos para evitar situaciones y/o eventos de emergencia en la prevención de lesiones y accidentes del trabajo.
VIRUS Y ENFERMEDADES CRÓNICAS
Authors: Castaño Osorio Jhon Carlos
Published: May 2019

Los virus como agentes infecciosos cada día se implican en la fisiopatogenesis de un sin número de enfermedades crónicas, de diversos espectros clínicos que van desde las enfermedades mentales, la obesidad, el síndrome de fatiga crónica, la diabetes mellitus y la enfermedad cardiovascular. En este artículo de revisión se hizo un esfuerzo por recopilar la información actualizada de los diferentes agentes virales implicados en la génesis de las enfermedades crónicas antes mencionadas, así como de los posibles mecanismos fisiopatológicos implicados en el desarrollo de estas enfermedades después de la infección viral tanto en animales como en humanos.
DEPTH MAP ESTIMATION IN LIGHT FIELDS USING AN STEREO-LIKE TAXONOMY
Authors: Calderon Francisco C. , Parra Carlos A. , Niño Cesar L.
Published: May 2019

The light field or LF is a function that describes the amount of light traveling in every direction (angular) through every point (spatial) in a scene, this LF can be captured in several ways, using arrays of cameras, or more recently using a single camera with an special lens, that allows the capture of angular and spatial information of light rays of a scene (LF). This recent camera implementation gives a different approach to find the dept of a scene using only a single camera. In order to estimate the depth, we describe a taxonomy, similar to the one used in stereo Depth-map algorithms. That consist in the creation of a cost tensor to represent the matching cost between different disparities, then, using a support weight window, aggregate the cost tensor, finally, using a winner-takes-all optimization algorithm, search for the best disparities. This paper explains in detail the several changes made to an stereo-like taxonomy, to be applied in a light field, and evaluate this algorithm using a recent database that for the first time, provides several ground-truth light fields, with a respective ground-truth depth map.
SISTEMA ANTI COLISIONES PARA NAVEGACIÓN EN INTERIORES DE UN QUACOPTER USANDO UN CONTROLADOR DIFUSO Y SENSORES DE RANGO
Authors: Fonnegra Tarazona Rubén Darío , Ríos Lopera Felipe , Góez Sánchez Germán David
Published: May 2019

Este proyecto presenta los resultados de la introducción de un control de velocidad mediante la utilización de sensores de ultrasonido y acelerómetro para la detección de objetos, asociados a un controlador difuso para prevenir colisiones en espacios cerrados. Con la implementación de este modelo anti colisión, la navegación de robots aéreos en interiores se hace más segura.
CONTROL DE CALIDAD ÓPTICO DE GEM FOILS
Authors: Rodríguez César A. , Gutiérrez Rafael M. , Jaramillo Andrés E.
Published: May 2019

El Multiplicador de Electrones de detectores Gaseosos (GEM) es una de las tecnologías útiles y potentes de detectores gaseosos de ionización usados en física de altas energías, física médica y otras aplicaciones. Uno de los elementos básicos de un GEM es la placa con micro perforaciones. Las características de tales perforaciones son fundamentales para un desempeño óptimo del GEM. En este trabajo se comparan diferentes métodos computacionales (implementados en lenguaje de programación Java) con el fin de determinar la calidad de las placas-GEM a partir de imágenes de alta resolución de dichas placas. El método computacional propuesto proporciona una solución alternativa automática y de alta precisión con respecto a las técnicas manuales lentas e imprecisas que se emplean actualmente, las cuales representan una limitación para el desarrollo y aplicación de esta tecnología de detectores.
L’église Saint-Liphard et la tour Manassès de Garlande à Meung-sur-Loire
Authors: Mesqui Jean
Published: May 2019

La petite ville épiscopale de Meung-sur-Loire possède un ensemble monumental remarquable, constitué par la collégiale Saint-Liphard, le clocher et la tour maîtresse résidentielle de l’évêque qui forment son massif occidental. Une nouvelle approche associant la recherche documentaire, l’exploitation des données archéologiques acquises ces dernières années, enfin un relevé précis de l’architecture du monument, permet de réévaluer les fonctions et les datations des différentes parties du monument, et de mettre en évidence la fonction particulière jouée par le clocher contenant une chapelle privée à côté de la résidence épiscopale, elle-même accolée à l’église. C’est aussi l’occasion de souligner la place très importante de ce monument dans les différentes étapes de l’installation du premier art gothique de l’Orléanais ; on découvre ainsi le rôle majeur joué par la famille de Garlande, à trois générations consécutives marquées par le chancelier royal et archidiacre Étienne, suivi par les deux évêques d’Orléans Manassès et Hugues, dans le développement et l’implantation du gothique au sein de cette région attachée aux traditions romanes.
Philibert Delorme à l’hôtel d’Angoulême ? Réflexions sur une attribution
Authors: Guillaume Jean
Published: May 2019

Philibert Delorme and the Hôtel d’Angoulême ? Reflections on an attribution

Documents found recently by Guy-Michel Leproux led him to believe that construction of the Hôtel d’Angoulême, thought to have been built by Diane de France in 1584, began in 1560 and that Philibert Delorme was the architect. That attribution is justified, but the hotel built in 1560 is definitely not the present hotel which is situated on the northern half of the (very large) parcel of land. Philibert’s hotel was erected on the southern half of the plot, with one of its walls bordering the rue de la Porcherie. Diane lived there, and then aroung 1605-1610 she decided for unknown reasons to build the present hotel, which embraced the northern extremity of the previous one. The architectural forms, which recall nothing of the Delorme’s refined art, fit perfectly with that date. The rather mediocre architect (badly) imitated the colossal order of the western part of the Grande galerie.
La mobilité du travailleur détaché, aspects de droit du travail
Authors: Garnier Sophie
Published: May 2019

Le détachement de travailleurs est une hypothèse de mobilité des personnes qui met en œuvre de manière singulière les règles de droit international privé. Les travailleurs détachés par leur employeur sur le territoire d’un autre État membre doivent se voir appliquer un «noyau dur » de dispositions impératives du lieu de détachement. La thématique, d’une grande actualité, implique que des arbitrages soient effectués afin de déterminer la législation du travail applicable, entre respect du principe de la libre prestation de services et protection des travailleurs.
Determining the optimal age of breeding gilts and its impact on lifetime performance, Literature review
Authors: Joab Malanda
Published: May 2019

Lifetime sow performance is a critical indicator for producers managing a commercial sow herd. It is comprised of sow longevity, lifetime piglets born alive, lifetime number of pigs weaned and lifetime non-productive sow days. Increased lifetime performance and longevity in sows reduces costs of replacement gilts and improves herd performance and profitability (Sasaki et al., 2008, 2011). One of the most critical factors driving the performance of sow herds is gilt management. Decisions regarding gilts have profound effects on sows’ lifetime performance. Age at first breeding of a gilt is a management decision that has been shown to affect performance and retention of the gilt in a herd.

The main aim of this review is to establish factors affecting age of first breeding of gilts and its impact on lifetime performance.