bluuebunny/crossref_metadata_2025 huggingface dataset:
The “Gentle Lie”: Women and the GDR Medical System in Film and Literature
Authors: Klocke Sonja E.
Published: May 2017

Abstract | Within the context of medical-historical research, this article compares the depiction of female patients in GDR and post-GDR fictional texts: Lothar Warneke’s Die Beunruhigung (1982), Christa Wolf’s Nachdenken über Christa T. (1968) and Leibhaftig (2002), and Kathrin Schmidt’s Du stirbst nicht (2009). This approach highlights the idiosyncrasies of GDR medicine, which demanded patients’ collaboration in therapeutic measures and hid from them the truth about their conditions. This custom, known as the “gentle lie,” as well as other top-down practices echo the state’s patriarchal attitude towards its citizens, particularly women, evidencing that the GDR claim of gender equality was not practiced in key areas of women’s lives. Furthermore, there is evidence that hierarchical structures denying patients’ agency persist today in eastern Germany. Résumé | Dans une perspective médico-historique, cet article compare la description de patientes dans des récits de fiction de la RDA et de l’ex-RDA: L’Inquiétude (Die Beunruhigung) de Lothar Warneke (1982), Christa T. (Nachdenken über Christa T.) (1968) et Le Corps même(Leibhaftig) de Christa Wolf (2002) ainsi que Tu ne vas pas mourir (Du stirbst nicht) de Kathrin Schmidt (2009). Cette approche met en lumière les idiosyncrasies de la médecine de la RDA, laquelle demandait la collaboration des patients dans les mesures thérapeutiques tout en leur cachant la vérité sur leur condition. Cette pratique—connue sous le nom de « doux mensonge »—ainsi que d’autres pratiques imposées d’en haut reflètent l’attitude patriarcale de l’État envers ses citoyens, et tout particulièrement envers les femmes, preuve que la revendication—faite par la RDA—de l’égalité des sexes n’était pas mise en œuvre dans des secteurs clés de la vie des femmes. En outre, tout porte à croire que les structures hiérarchiques privant les patients d’initiative continuent de se perpétuer aujourd’hui dans l’Est de l’Allemagne.
It Tastes like the East…: The Problem of Taste in the GDR
Authors: Weinreb Alice
Published: May 2017

Abstract | This essay uses the topic of taste, specifically taste for food, as a way of unpacking the history of the GDR and East-West relations during the late Cold War. It explores the question of East German tastes from two angles: West German fantasies about the inadequacies of the GDR’s food system, and East German nutritionists’ unsuccessful struggles to regulate popular tastes. In particular, it focuses on the moment when popular taste was seen as a serious problem by the GDR state—during the rise of the obesity epidemic in the 1970s and 1980s. Résumé | Cet essai utilise le thème du goût, spécifiquement le goût pour la nourriture, comme un moyen de dévoiler l’histoire de la RDA et les relations Est-Ouest pendant la fin de la guerre froide. Il examine la question des goûts de l’Allemagne de l’Est sous deux angles: Les fantaisies des ouest-allemands sur les insuffisances du système alimentaire de la RDA, et les luttes infructueuses des spécialistes de la nutrition est-allemands pour réglementer les goûts populaires. L’essai se concentre en particulière sur le moment où le goût populaire a été considéré comme un problème grave par l’état de la RDA—pendant l’augmentation de l’épidémie d’obésité dans les années 1970 et 1980.
Troubled Faces: The Melancholy Passion of Anna Seghers’s Die Entscheidung
Authors: Robinson Benjamin
Published: May 2017

Abstract | Among the plotlines in Anna Seghers’ 1959 novel of socialist construction, Die Entscheidung, the love story remains the most realistic allegory for understanding passionate motivations for socialism. This reading reveals how Seghers has moved the locus of insight from characters in her early novels who gain ideological consciousness in mortal struggle against repression to characters who discover ideological limits in the face of creaturely involvements. The sacrifice of the Catholic wife of a communist engineer points to the persistence of the body, labour, and birth, with their concomitant emotions of compassion and romance. By directing attention away from doctrinaire elements, my reading explores how the particulars of care encounter the generalities of collectivism. Résumé | Dans le roman d’Anna Seghers de 1959, Die Entscheidung, roman de construction socialiste, l’histoire d’amour reste l’allégorie la plus réaliste pour comprendre certaines motivations passionnées pour le socialisme. Cette intervention montre comment Seghers a déplacé le lieu de connaissance de la lutte forcenée contre la répression (dans ses premiers romans) aux personnages qui se heurtent aux limites idéologiques devant leurs engagements corporels. Le sacrifice de la femme catholique d’un ingénieur communiste pointe vers la persistance du corps, du travail et de l’accouchement, avec leurs sentiments de compassion et de rêve. En écartant l’attention des éléments doctrinaires, cette intervention interroge les façons dont les particularités des soins rencontrent les généralités du collectivisme.
Phenotypic Plasticity and Cell Fate Decisions in Cancer: Insights from Dynamical Systems Theory
Authors: Jia Dongya , Jolly Mohit Kumar , Kulkarni Prakash , Levine Herbert
Published: May 2017

Waddington’s epigenetic landscape, a famous metaphor in developmental biology, depicts how a stem cell progresses from an undifferentiated phenotype to a differentiated one. The concept of “landscape” in the context of dynamical system theory represents a high-dimensional cell state space, in which each cell phenotype is considered as an “attractor” that is determined by interactions among multiple variables (molecular players), and is buffered against environmental fluctuations. Further, biological noise is thought to play an important role during these cell-fate decisions and in fact controls transitions between different phenotypes. Here, we discuss these phenotypic transitions in cancer from a dynamical systems perspective and invoke the concept of “cancer attractors” – hidden stable states of the underlying regulatory network that are not occupied by normal cells. Using epithelial-to-mesenchymal transition (EMT), cancer stem-like properties, metabolic reprogramming and the emergence of drug/hormone resistance as examples, we illustrate how phenotypic plasticity in cancer cells enables them to acquire hybrid phenotypes (such as hybrid epithelial/mesenchymal and hybrid metabolic phenotypes) that tend to be more aggressive and notoriously resilient to drug/hormone treatment. Furthermore, we highlight multiple factors that may give rise to phenotypic plasticity in cancer cells, such as (a) multi-stability or oscillatory behaviors governed by underlying regulatory networks involved in cell-fate decisions in cancer cells, and (b) network rewiring due to conformational dynamics of intrinsically disordered proteins (IDPs) that are highly enriched in cancer cells. We conclude by discussing why a therapeutic approach that promotes ‘recanalization’, i.e. the exit from “cancer attractors” and re-entry into “normal attractors”, is more likely to succeed rather than a conventional approach that targets individual molecules/pathways.
A Forward GPS Multipath Simulator Based on the Vegetation Radiative Transfer Equation Model
Authors: Wu Xuerui , Jin Shuanggen
Published: May 2017

GNSS have been widely used in navigation, positioning and timing. Nowadays, the multipath errors previously considered detrimental may be re-utilized for the remote sensing of geophysical parameters (soil moisture, vegetation and snow depth), e.g. GPS- Multipath Reflectometry (GPS-MR). In this paper, a new element describing bistatic scattering properties of vegetation is incorporated into the traditional GPS-MR model. This new element is the first-order radiative transfer equation model. The new forward GPS multipath simulator is able to explicitly link the vegetation parameters with GPS multipath observables (signal-to-noise-ratio (SNR), code pseudorange and carrier phase observables). The trunk layer and its corresponding scattering mechanisms are ignored since GPS-MR is not suitable for high forest monitoring due to the coherence of direct and reflected signals. Based on this new model linking the GPS observables (SNR, phase and pseudorange) with detailed vegetation parameters, the developed simulator can present how the GPS signals (L1 and L2 carrier frequencies, C/A, P(Y) and L2C modulations) are transmitted (scattered and absorbed) through vegetation medium and received by GPS receivers. Simulation results show that wheat will decrease the amplitudes of GPS multipath observables, if we increase the vegetation moisture contents or the scatters sizes (stem or leaf), the amplitudes of GPS multipath observables (SNR, phase and code) decrease. Although the Specular-Ground component dominates the total specular scattering, vegetation covered ground soil moisture has almost no effects on the final multipath signatures. Our simulated results are consistent with published results for environmental parameter detections with GPS-MR.
The Effect of Silver Nanoparticles Size, Produced Using Plant Extract from Arbutus Unedo, on Their Antibacterial Efficacy
Authors: Skandalis Nicholas , Dimopoulou Anastasia , Georgopoulou Anthie , Gallios Nikolaos , Papadopoulos Dimitrios , Tsipas Dimitrios , Theologidis Ioannis , Michailidis Nikolaos , Chatzinikolaidou Maria
Published: May 2017

Silver nanoparticles (AgNPs) have been demonstrated to restrain bacterial growth while maintaining the minimal risk in development of bacterial resistance and human cell toxicity that conventional silver compounds exhibit. Several physical and chemical methods have been reported to synthesize AgNPs. However, these methods are expensive and involve heavy chemical reduction agents. An alternative approach to produce AgNPs in a cost-effective and environmentally friendly way employs a biological pathway using various plant extracts to reduce metal ions. The size control issue and the stability of nanoparticles remain some of the latest challenges in such methods. In this study, we used two different concentrations of fresh leaf extract of the plant Arbutus Unedo (LEA) as a reducing and stabilizing agent to produce two size variations of AgNPs. UV-Vis spectroscopy, Dynamic Light Scattering, Transmission Electron Microscopy and zeta potential were applied for the characterization of AgNPs. Both AgNP variations were evaluated for their antibacterial efficacy against the gram-negative species Escherichia coli and Pseudomonas aeruginosa, as well as the gram-positive species Bacillus subtilis and Staphylococcus epidermidis. Although significant differences have been achieved in the nanoparticles’ size by varying the plant extract concentration during synthesis, the antibacterial effect was almost similar.
The Essential Oils from Pittosporum tobira Flowers Display Antiproliferative Properties and Inducing Apoptosis on Lung Carcinoma Cells
Authors: Sun Yan-Fang , Wink Michael , Wang Zhang-Qi , Lu Hong-Fei , Xia Peng-Guo , Liu Hong-Tao , Wang Shi-Xian , Sun Yang , Liang Zong-Suo
Published: May 2017

Background: Pittosporum tobira (Thunb.) Aiton is an aromatic medicinal plant widely cultivated in the world. However, the essential oils (EOs) from P. tobira flowers for anti-cancer potential is still not systematically studied. The present aim to elucidate the phytochemical composition of the EOs and to explore mechanism of anticancer action. Methods: The EOs were extracted and analyzed by headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS). Volatile components were identified according to Kovats retention index (KI) and NIST database. The anti-neoplasm mechanisms of the EOs was comprehensively investigated in lung carcinoma A549 and H460 cells. Results: A total of 47 secondary metabolites representing 94.18% of the EOs were successfully identified: monoterpenes and sesquiterpenes were the dominant terpenoids. The EOs exhibited antiproliferative activity on A549 and H460 lung carcinoma cells. Hoechst 33324 fluorescent staining indicated the typical characteristics of apoptosis and induced cycle phase arrest. AnnexinV/PI staining revealed that the number of apoptotic cells was increased. Furthermore, the EOs also induced the caspase-mediated mitochondrial apoptosis pathway. Conclusions: Findings suggest that the full-scale chemical composition and first characterization of anticancer activities of the EOs, it could be used for integrative natural anti-cancer agents in health care should be pay more attention.
Spatial Distribution of Population Density and Pressure on Sustainable Cropland Use in Shandong Province in China during the 17th-20th Century
Authors: Ye Yu , Wei Xueqiong , Fang Xiuqi , Li Yikai
Published: May 2017

Cropland area per capita and pressure index on cropland is the important parameters measuring the social vulnerability and sustainability in the perspective of food security in a certain region in China during the historical periods. This study reconstructs the spatial distribution change of cropland area per labor/household and pressure index on cropland during the 17th-20th century by the methods of historical documents, regression analysis, pressure index model and GIS. Then it analyzed the impacting process of climate change and sustainability of cropland use during the different periods. It draws conclusions: (i) the spatial difference of labor/household density was obvious which had the same pattern as cropland distribution during the same periods, which is higher density in three agricultural areas. (ii) Cropland area per capita was relatively higher during the 17th-18th century, which were above 0.4 ha/person in majority counties and distributed homogenously. Till the 19th century and the beginning of 20th century, cropland area per capita in large amount of regions decreased below 0.2 ha/person embodying the increase of social vulnerability and unsustainability at that time. (iii) Pressure index on cropland also showed the similar spatial pattern as cropland area per capita which presented lower threshold than nowadays. During the 17th-18th century there was no pressure on cropland. While, in the 19th century and at the beginning of 20th century, two high value centers of pressure index on cropland appeared in Middle Shandong and the Jiaodong region, pressure on sustainable cropland use increased obviously and a food crisis is probably created. (iv) Higher sustainable extent of cropland use corresponds to cold period, and lower sustainable extent of cropland use corresponds to warm period in Shandong over the past 300 years. The turning point of 1680s from dry to wet attributes to the decrease of sustainable extent of cropland use in Shandong not very distinctively. More and more pressure on sustainability of cropland use finally since the beginning of 20th century would intensify the social conflict and increase the probability of social revolts.
Instantaneous Symmetrical Component Estimator Using Second Order Generalized Integrator under Distorted Voltage Conditions
Authors: Ozsoy Emre , Padmanaban Sanjeevikumar , Siano Pierluigi , Ahmad Fiaz , Akhtar Rasool , Sabanovic Asif , Loia Vincenzo
Published: May 2017

Frequency, amplitude and phase information of the grid voltage are of great importance in constructing a robust controller structure for grid connected inverter systems. This paper presents a simple and robust approach for the instantaneous estimation of positive and negative sequence voltage components under distorted voltage conditions. A second order generalized integrator (SOGI) is used to filter the distorted voltage and to generate orthogonal voltage components for each of the three phases. These filtered and orthogonal components are used for instantaneous calculation of symmetrical components. The implemented method is frequency adaptive; the method is demonstrated and compared to a conventional phase locked loop (PLL) technique with both MATLAB/Simulink simulations and experiments utilizing the dSPACE ds1103 digital controller.
Investigation on Development of Sliding Mode Controller for Constant Power Loads in Microgrids
Authors: Hossain Eklas , Perez Ron , Padmanaban Sanjeevikumar , Siano Pierluigi
Published: May 2017

To implement renewable energy resources, microgrid systems have been adopted and developed into the technology of choice to assure mass electrification in the next decade. Microgrid systems have a number of advantages over the conventional utility grid systems, however, it faces severe instability issues due to continually increasing constant power loads. To improve the stability of the entire system, load side compensation technique is chosen because of its robustness and cost effectiveness. In this particular occasion, a sliding mode controller is developed for microgrid system in the presence of CPL to assure certain control objective of keeping the output voltage constant at 480V. After that, the robustness analysis of the sliding mode controller against parametric uncertainties is presented. The sliding mode controller robustness against parametric uncertainties, frequency variations, and additive white Gaussian noise (AWGN) are illustrated in this paper. Later, the performance of the PID and sliding Mode controller is compared in case of nonlinearity, parameter uncertainties, and noise rejection to justify the selection of Sliding Mode controller over PID controller. All the necessary calculations are reckoned mathematically and results are verified in the virtual platform such as MATLAB/Simulink with the appreciable outcome.
Air Pollution Monitoring in the south-east baltic using the epiphytic lichen hypogymnia physodes
Authors: Koroleva Yulia , Revunkov Vladimir
Published: May 2017

Epiphytic lichens are well-known indicators of air contamination. The chemical composition of lichens is affected by the concentration of pollutants in the environment. Usually, researchers assess long-term variations in trace elements or other pollutants in the study area or identify the spatial features of air contamination. The aim of this study is to create a database of trace element concentrations in the samples of the epiphytic lichen Hypogymnia physodes growing in the Kaliningrad region. The database can be used as a ‘reference point’ for monitoring studies. Another objective is to identify the spatial patterns of iron, manganese, nickel, cadmium, silver, lead, strontium, rubidium, and calcium in the Kaliningrad region. The samples of wild lichens were collected from pine and birch trees 1.2-1.8 m from the bases of the threes, using a regular grid, in August 2010. One-two-year-old thalli were used in the chemical analysis. The metals Ag, Cd, Cu, Pb, Ni, Fe, Mn, and Zn were determined by AAS (Mn, Fe by flame AAS and the others by ETA-AAS) and the elements Sr, Rb, and Ca by X-ray fluorescence. The concentration of metals in the western coastal area (the Sambian or Kaliningrad Peninsula) is higher than it is in the central and eastern parts of the region. Principal component factor analysis was carried out to detect and characterise different pollution sources and to identify the most polluted areas. The factors of metal emission were described. The authors examined the features of the spatial distribution of trace elements. Prevailing winds are form south-west. Therefore, the highest concentrations of trace elements were found on the Sambian peninsula and on the coasts of the Vistula and Curonian Lagoons. The high concentrations of trace elements in the samples of the lichen H.physodes, which were observed in the coastal part of the region, are associated with human impact and subsequent pollution. The chemical composition of lichens on the Sambian peninsula may have developed under the impact of both local pollution sources – vehicles, thermal energy facilities, and ports – and such factors as transboundary traffic and sea spray.
Gravitation-Based Edge Detection for Hyperspectral Images
Authors: Sun Genyun , Zhang Aizhu , Ren Jinchang , Ma Jingsheng , Wang Peng , Zhang Yuanzhi
Published: May 2017

Edge detection is one of the key issues in the field of computer vision and remote sensing image analysis. Although many different edge-detection methods have been proposed for gray-scale, color, and multispectral images, they still face difficulties when extracting edge features from hyperspectral images (HSIs) that contain a large number of bands with very narrow gap in the spectral domain. Inspired by the clustering characteristic of the gravitation, a novel edge-detection algorithm for HSIs is presented in this paper. In the proposed method, we first construct a joint feature space by combining the spatial and spectral features. Each pixel of HSI is assumed to be a celestial object in the joint feature space, which exerts gravitational force to each of its neighboring pixel. Accordingly, each object travels in the joint feature space until it reaches a stable equilibrium. At the equilibrium, the image is smoothed and the edges are enhanced, where the edge pixels can be easily distinguished by calculating the gravitational potential energy. The proposed edge-detection method is tested on several benchmark HSIs and the obtained results were compared with those of three state-of-the-art approaches. The experimental results confirm the efficacy of the proposed method
Spatial Pattern Dynamics Analysis in Coastal Area Using Spatial Metric in Pekalongan, Indonesia
Authors: Wijaya Ali , Susetyo Cahyono , Diny Azillatin Q. , Nabila Danika H. , Pamungkas Rahel P. , Hadikunnuha Mohammad , Pratomoatmojo Nursakti A.
Published: May 2017

Pekalongan is one of several cities that lies in the northern coast of Java island which is often flooded due to sea level rise. This condition impacted its urban development characteristic and increase in the future. In this research both Geographical Information System based and Spatial Metric approach are used. The spatial pattern is analyzed by using spatial metric based on the exploration of land use change that occurred. In this research, the spatial pattern is focused on aggregation pattern and diversity in coastal area. The result shows that the land use of coastal area are dominated with swamp, then followed by settlement and fishpond. It is also shown that the greatest land use change occurred on paddy field and swamp areas. Based on the spatial metric calculation, the aggregation level of land use decrease periodically and has a small growth level. It is indicated from its metric value aggregation and diversity from two periods: 2003-2009 and 2009-2016. Overall the land use of Pekalongan experienced large dynamics, especially in its coastal area. The spatial pattern trend in those area tend to be more sprawl as defined by the decrease of aggregation pattern and low level of land use growth pattern.
Numerical Analysis of Unsymmetric Flatbak Trailing Edge Airfoil to Reduce Turbomachinery Noise in Power Generation Cycle
Authors: Shin Hyungki , Kim Hogeon , Kim Taehyung , Kim Soo-Hyun , Lee Soogab , Baik Young-Jin , Lee Gilbong
Published: May 2017

A turbomachinery is essential part in the power generation cycle. But, it is main noise source to annoy workers and users and to make environmental problem. Thus it is important to reduce this noise for operating the power generation cycle. This noise is created by flow instability on rotor blade trailing edge. An airfoil that becomes a section of a rotor blade of a rotating machine is manufactured as a blunt trailing edge (TE) with a round or flatback shape rather than the ideal sharp TE shape for the purposes of producibility and durability. This increases the tonal noise and flow-induced vibration at low frequency owing to vortex shedding behind TE when compared with a sharp TE. In order to overcome this problem, this study investigates the oblique TE shape using numerical simulation. In order to do so, the flow was simulated using large eddy simulation (LES) and the noise was analysed by acoustic analogy coupled with LES result. Once the simulation results were verified using the flatback airfoil measurements of Sandia National Laboratories, numerical prediction was performed for airfoils modified to have oblique trailing edge angles of 60°, 45°, and 30° to analyse the flow and noise characteristics. From the simulation results for an airfoil having an oblique TE, it could be seen that the vortex shedding frequency moves in accordance with the oblique angle and that the vortex shedding noise characteristics change according to this angle when compared to the flatback TE airfoil. Therefore, it is considered that modifying the flatback TE airfoil to have an appropriate oblique angle can reduce noise and change the tonal frequency to a bandwidth that is suitable for mechanical systems.
Densities and Refractive Indices of Potassium Carbonate -Based Deep Eutectic Solvents with Dual Hydrogen Bond Donors at Several Temperatures (293.15 to 343.15 K)
Authors: Ghaedi Hosein , Ayoub Muhammad , Sufian Suriati , Mohd Shariff Azmi , Lal Bhajan
Published: May 2017

Deep eutectic solvents (DESs) are known as tunable solvents. It is possible to prepare ternary deep eutectic solvent (TDES) are used for desired purpose by selecting the suitable molar ratio and components of mixture. Therefore, four DESs and two TDESs were prepared in this work. DESs and TDESs were prepared with potassium carbonate (PC) as a hydrogen bond acceptor (HBA) and three hydrogen bond donors (HBDs) such as glycerol (GL), ethylene glycol (EG) and 2-amino-2methyl-1-3-propanediol (AMPD) known as a hindered amine (HA). Binary DESs were PC-GL with molar ratios 1:10 and 1:16 and PC-EG with the same molar ratios. TDES were prepared by adding AMPD in binary DESs such as PC-GL-AMPD 1:16:1 and PC-EG-AMPD 1:10:1. The experimental density and refractive index of all DESs and TDESs were measured at the temperature of 293.15 to 343.15 K with an interval of 5 K. The effect of temperature, molar ratio and alkyl chain length on the properties was investigated. The molar volumes and isobaric thermal expansion were calculated using experimental density data. The experimental refractive index data was used to derive the specific refraction, molar refraction, free molar volume, electronic polarization, polarizability constant and internal pressure at several temperatures.
Spatial Pattern Dynamics Analysis at Coastal Area Using Spatial Metric in Pekalongan, Indonesia
Authors: Wijaya Ali , Susetyo Cahyono , Diny Azillatin Qisthian , Nabila Danika Hudani , Pamungkas Rahel Putri , Hadikunnuha Mohammad , Pratomoatmojo Nursakti Adhi
Published: May 2017

Pekalongan is one of several cities that lies in the northern coast of Java island which is often flooded due to sea level rise. This condition impacted its urban development characteristic and increase in the future. In this research both Geographical Information System based and Spatial Metric approach are used. The spatial pattern is analyzed by using spatial metric based on the exploration of land use change that occurred. In this research, the spatial pattern is focused on aggregation pattern and diversity in coastal area. The result shows that the land use of coastal area are dominated with swamp, then followed by settlement and fishpond. It is also shown that the greatest land use change occurred on paddy field and swamp areas. Based on the spatial metric calculation, the aggregation level of land use decrease periodically and has a small growth level. It is indicated from its metric value aggregation and diversity from two periods: 2003-2009 and 2009-2016. Overall the land use of Pekalongan experienced large dynamics, especially in its coastal area. The spatial pattern trend in those area tend to be more sprawl as defined by the decrease of aggregation pattern and low level of land use growth pattern.
A Speculative Model of Thermally Forced Quasi-Geostrophic Flow in an Unbounded Ocean
Authors: Crisciani Fulvio , Purini Roberto , Mosetti Renzo
Published: May 2017

Starting with a hypothetical geostrophic zonal current in an unbounded ocean, the investigation points out the response of this simple system to a thermal forcing, applied to the free surface and consistent with the maintenance of the geostrophic balance. The main result is the formation of a meridional component of the current, according to the Sverdrup relation, such that the full velocity vector rotates clockwise for heating and anticlockwise for cooling to adjust eventually in the initial zonal direction for large depths.
Progress and Prospect on Stability of Perovskite Photovoltaics
Authors: Ezike Chinedu Sabastine , Kana G.M. Zebaze , Aina A. O.
Published: May 2017

Solar energy has the potential to solve world energy problem as it is pollution- free. It could be enhanced using perovskite material as an absorber in perovskite solar cells. The history and what this material is made up of are emphasized. Different methods of fabrication, improving the power conversion efficiency (PCE) and factors influencing degradation of perovskite-based solar are stated. Because of the fact that this material based solar cells are not yet developed, its stability was reviewed to bring different technology employed in tackling the stability aiming for a better understanding of the material and the devices and facilitates the commercialization of perovskite solar cell.
Beam elements as approximate models of vibrating mechanical subsystems of freight wagons
Authors: Buchacz Andrzej
Published: May 2017

The complex mechanical system which is a subsystem of mechatronic system composed with many continuous mechanical elements having the same length and variable cross section, loaded by the harmonic force is analyzed. The main subject of deliberation was to determine the flexibility of the mechanical subsystem with constant cross section using algorithms of exact and approximate methods. Next, the comparison of methods and the correction of the approximate method has been made. The model of subsystem of complex transverse vibrating mechanical system of freight wagon was considered and after deliberation the approximate method has been chosen. The presented research of subsystems establishes the foundation to complex systems analysis with cascade structure. By analyzing the diagrams of characteristics of confirmed system it has been determined that in case of approximate method the resonance frequencies cover with those which have been determined with the exact method. However, the values of the characteristic in other areas are different. Therefore, there is the mistake within the approximate method, which while of studying the single system does not have any influence because in resonance areas the characteristic values of the system approach to the infinity. However, the difference between values of flexibility within two methods has the great influence on the result of complex systems. That is why it was necessary to correct the results of the approximate method.
A ship’s magnetic field camouflage method based on multi-objective genetic algorithm
Authors: Tian Dong , Liu Sheng-dao , Li Zhi-xin
Published: May 2017

In order to protect the ship’ s magnetic field information from detection, a method is proposed to camouflage both the amplitude and curve of ship’s magnetic field based on multi-objective genetic algorithm. The example shows that the method can camouflage the ship’s magnetic amplitude and curve feature effectively, the multi-objective genetic algorithm can avoid the subjective of weight distribution in the unified objective method and the alternative Pareto disaggregation can be found, which is more adaptable for application requirement.
Numerical modelling of scour around circular cylinder caused by jet flow and bed shear stress
Authors: Kim Hyoseob , Lee Seungho , Lee Jungik , Lim Hak Soo , Ryoo Hee-Suk
Published: May 2017

A new scour numerical model composed of two modules is proposed here. The two modules are detailed Reynolds-average Navier-Stokes flow module and sediment transport and resultant scour module. The flow module uses horizontally regular grid at the bed but partial grid concept in the vertical direction. The sediment module operates entrainment, and deposition of suspended sediment. The entrainment of sediment is computed by a new empirical equation; the major independent variables of which are the jet flow velocity and the bed shear stress. The model is applied to a laboratory scour experiment around a circular cylinder at Kookmin University, and shows satisfactory agreement with measurements.
Investigation of vibrations during deepholes machining
Authors: Kondratenko Leonid , Mironova Lyubov , Terekhov Viktor
Published: May 2017

The article describes the method for studying the dynamics of the cutting tool in the processing of deep holes. Instead of the classic second-order differential equation, two first-order equations introduced. These equations relate the angular acceleration and angular velocity with the shear stress.
Seismic response analysis on shear lag effect of continuous curved box girder with three spans
Authors: Lu Hailin , Cai Heng , Yang Hongyin , Xue Kaiyi
Published: May 2017

Shear lag effect of continuous curved box girder with three spans under seismic excitation is studied in this paper. Firstly, spatial shell finite element model is founded by ANSYS, and EL-centro seismic wave is chosen as seismic excitation. Secondly, the shear lag effect at different cross sections are investigated with dynamic time-history analysis, the results show that under seismic excitation there is prominent shear lag effect in continuous curved box girder, the maximum shear lag coefficient is 3.02, shear lag effect is severe, shear lag effect at mid-span cross sections are prominent than support cross sections, and inside peak shear lag coefficients are generally greater than outside. Finally, the numeric results are compared with the experimental results from a vibration table testing, which shows great consistencies.
Waterproof ultrasonic motor
Authors: Toyama S. , Nishizawa U.
Published: May 2017

The authors have been making a multi degree of freedom piezoelectric actuator that has Translational and Rotational motions in one joint (TR motor). Because the motor has the advantages such as simple structure and excellent controllability, it has high potentials for wide use in non-industrial applications. The authors will apply it to outdoor use, especially, use in water. The authors have applied insulating process to the piezoelectric element for waterproof and designed an optimal shape of it for driving in water to show driving TR motor in water successfully.
Physiological effect of graphene oxide on tobacco BY-2 suspension cells and its immigration
Authors: Chen Nannan , Feng Peng , Liao Xianyan , Li Ping , Liu Zhanmin , Huang Junyi
Published: May 2017

More and more attentions are paid to the potential effect of graphene oxide (GO) in environment and human beings. In order to evaluate the effect of GO on plant, tobacco BY-2 suspension cells were employed as material, and the physiological effect of GO on tobacco BY-2 suspension cells and its immigration were investigated. The results showed that low concentrations of GO (25 and 50 μg/mL) promoted cells growth (increased by 11.22 % in 50 μg/mL GO), while higher concentrations of GO (100 and 200 μg/mL) induced inhibition in cell growth (decreased by 9.68 % in 200 μg/mL GO). GO caused an increment in activity levels of SOD, POD and CAT, but the activity levels decreased with the extension of culture time in higher concentration. The results showed that GO could make cell nuclei fragment and loose in a higher concentration. These results imply that there is an adverse effect of GO on plant cells, and suggest that nano pollution should be paid attention to.
Combination rules for steel buildings under seismic loading: MDOF vs SDOF systems
Authors: Reyes-Salazar Alfredo , Llanes Tizoc Mario , Bojorquez Eden , Bojorquez Juan , Valenzuela-Beltran Federico , Gaxiola-Camacho Jose
Published: May 2017

Some factors influencing the accuracy of the 30 % and SRSS rules commonly used to combine the effects of individual seismic components, are studied. For MDOF systems and earthquake loading the rules underestimate the axial load, but reasonably overestimate the shears. The rules are not always inaccurate in the estimation of the response for correlated components and totally uncorrelated (principal) components are not always related to an accurate estimation. The rules are not always associated to an inaccurate estimation for large values of the correlation of the individual effects (ρ), and small values of ρ are not always associated to principal components and to an accurate estimation. Only for uncorrelated harmonic excitations and elastic behavior of SDOF systems, the individual effects are not correlated, and the rules properly estimate the combined response. It seems like that the rules were developed by using SDOF systems. Thus, the accuracy of the rules varies with the response parameter, the location of the structural element, the model of the structural system and the level of deformation. All these factors should be considered while estimating the combined response according to the rules.
Maximum inter-story drift demands of steel frames in terms of the intensity measure INp
Authors: Bojórquez Edén , Baca Victor , Bojórquez Juan , Reyes-Salazar Alfredo , Chávez Robespierre , Hernández María
Published: May 2017

In the present work, a new equation to predict the maximum inter-story drift demands of mid-rise steel framed buildings is proposed in terms of a new ground motion intensity measures based on the spectral shape. For this aim, the maxim\um inter-story drift of steel frames with 4, 6, 8 and 10 stories subjected to several narrow-band ground motions is estimated as a function of the spectral acceleration at first mode of vibration SaT1, which is commonly used in earthquake engineering and seismology, and with a new parameter related to the structural response known as INp. It is observed that the spectral-shape-based intensity measure INp is the parameter best related with the structural response of the selected steel frames under narrow-band motions. For this reason, an equation to compute the maximum inter-story drift demand of mid-rise steel frames as a function of INp is proposed. The equation is useful for the rapid seismic assessment.
Lateral distribution calculation of multi-I beam composite curved bridge with slip effect
Authors: Qin Xuxi , Wu Chunli , Liu Hanbing , Xiang Chengxiu
Published: May 2017

This paper presents a modified rigid cross beam method to study the lateral distribution of multi-I beam composite curved bridge with slip effect. First, the effective stiffness expression of single composite curved beam with slip effect were established and calculated by the FEM. Secondly, the lateral load distribution of multi-I beam composite curved bridge is obtained by substituting the effective stiffness of the main composite curved beam into the rigid cross beam method. Finally, The FEM numerical examples show that this method can accurately describe the load distribution characteristics of multi-I beam composite curved bridge with slip effect.
Nanometric displacement measurement based on interference fringes deflection
Authors: González-Rivera Hely , Sandoval-Romero G. E.
Published: May 2017

A hybrid method to obtain nanometric displacements based on interference fringes movement by optical beam deflection is proposed. A proof-of-principle experiment is described as a new method for real-time detection and measurement of small vibrations, experimental results shows an increase in the resolution compared with a simply optical beam deflection read out. Also, there is minimum detectable displacement in an assumed noise environment.
Low-intensity acoustic waves detection using an interferometer
Authors: Álvarez-Ramírez F. J. , Sandoval Romero G. E.
Published: May 2017

We present a device built in fiber optic capable of detecting acoustic signals in water, using a buzzer as the vibration source, this buzzer operates at a frequency range from 3 kHz to 30 kHz. This device operates under the principle of a Sagnac interferometer, where the acoustic waves emitted by the buzzer are detected as a phase modulation in the monitored signal. The measured phase is due to strain experienced by the fiber optic which is caused by the vibrations emitted by the buzzer. The device can detect signals up to 7 cm away from the acoustic source.
Analysis and optimization of mutual influence of single channel tunnel construction blasting
Authors: Zhang Junfeng , Li Ming , Yang Xiaolin
Published: May 2017

In the current urban rail transit project in the vigorous development of the community, due to the needs of the site environment or line selection, it has been a common phenomenon in the actual construction of the tunnel encountered in the parallel operation and tunnel overlap situation, the new tunnel or tunnel group on the existing tunnel or other structure of the interaction problem has become very prominent! Based on the blasting excavation of the single-channel caverns in the first phase of the Chongqing Rail Transit Line 10 project, this paper makes a detailed investigation of the actual engineering, and uses ANSYS/LS-DYNA to simulate to comparative analysis and optimization the tunnel lining.
Analysis of hydrodynamic noise characteristics of rudder-wing
Authors: Qu Duo , Zhang Zhenhai , Lou Jingjun
Published: May 2017

The flow field and sound field of trapezoidal rudder-wing under different rudder angles are numerically predicted by CFD LES theory, Lighthill acoustic analogy theory and vibro-acoustic theory. And characteristics of hydrodynamic noise including flow noise and vibroacoustics under hydrodynamic excitations are analyzed. Results show that: at the same speed, the hydrodynamic noise raises with the increase of rudder angle; sound pressure level spectrum band of flow noise is wide and there is no obvious dominant frequency while there is a very obvious peak value of vibroacoustics under hydrodynamic excitations corresponding to the first order modal frequency in the band of 520-530 Hz; sound intensity at the front of leading edge and after trailing edge is higher than that at both sides of rudder-wing; the vibration of trailing edge is large, so it is the concentrated area of noise source.
Optimization for heat and sound insulation of honeycomb sandwich panel in thermal environments
Authors: Yuan Jinlong , Chen Haibo , Zhong Qiang , Li Kongjuan
Published: May 2017

An optimization based on sequential quadratic programming (SQP) algorithm to increase the thermal insulation and sound transmission loss of honeycomb panel in thermal environments is presented. First, heat transfer analysis is performed to reveal the steady-state thermal performance of hexagonal aluminum honeycomb sandwich panel, by using the semi-empirical Swann and Pittman formula. Next, the influences of temperature on acoustic performance of honeycomb panel based on statistical energy analysis method (SEA) is performed. Results show that increasing the thickness of the honeycomb core can improve the acoustic performance and heat insulation behavior.
Numerical simulation of high-speed water-entry for hemispherical-nosed projectile
Authors: Sun Yu-Song , Zhou Sui-Hua , Zhang Xiao-Bing
Published: May 2017

Aiming at the lack research of high-speed water-entry for large projectile, this paper studied the high-speed water-entry for hemispherical-nosed projectile in the method of fluid-solid coupling. Good agreements were obtained compared with the theoretical results. The modalities of water were calculated such as cavity, uplift and pressure. The velocity and deceleration curves of water-entry were gained. Numerical research shows that there is heavy shock pressure on the projectile and pressure waves in water by a projectile impacting into water at high speed, the pressure at the apex and the vicinity is much higher than the rest of area. The projectile’s peak acceleration is in linear correlation with the square of impact velocity. The simulation affords bases for impact-resistant design of the airdropped projectile, and of certain value to investigation of other correlative bodies’ high-speed water-entry.
Vibration based diagnosis of wheel defects of metro train sets using one period analysis on the wayside
Authors: Kılınç Onur , Vágner Jakub
Published: May 2017

This research examines two different methods; Wavelet Packet Energy (WPE) and Time-domain Features (TDF) which are effective in faulty signal feature extraction of metro wheels in wayside level using vibration sensors. Signals of each wheelset passing of a trainset with both healthy and faulty wheels are recorded by the vibration sensors which are mounted on both left and right rails and a novel one-period sampling is performed at 51.2 kHz sample rate. Retrieved signal samples are used in the construction of a database which is consistent of healthy and faulty cases. Since the database has insufficient number of faulty samples, the database is balanced by a method so called Adaptive Synthetic Sampling (ADASYN) so that each class has the same number of observations. Two state-of art classifiers; Support Vector Machines (SVM) and Fisher Linear Discriminant Analysis (FLDA) are employed by utilizing 16-fold cross validation to solve the two-class problem. Referring to the results, SVM-I-TDF outperforms by classifying all samples with a success rate of 100 % and other methods have also promising results. Proposed methods may be used in the condition monitoring of metro wheelsets effectively by means of not only performance but also cost-efficiency.
Study on the weight coefficient influence of surface water on the stability of open-pit dump. Comparative analysis of 6 degree seismic simulation
Authors: Xing Zhen-guo , Du Wenfeng
Published: May 2017

Taking Baorixile open-pit coal mine as an example, the regional hydrogeological conditions and the mining area hydrogeological conditions are briefly introduced. Analyzing the factors influencing the stability of open pit dump, discussing the classification and proportion of influencing factors, the numerical simulation of the influence of surface water and seismic vibrations on the stability of open-pit dump is carried out. Results show: Surface water is an important factor affecting the stability of open-pit dump, extremely sensitive to the safety factor, the influence of slope instability is similar to that of intensity 6 earthquake. The weight coefficient of surface water to slope stability is in the range of 0.4 to 0.9.
Influence of gear grip quality on noise levels of gearbox
Authors: Tomeh Elias , Oudrnický Tomáš
Published: May 2017

The test of traces prints, or sometimes called as “tests for colour” lie in examining the area where the teeth touch the gearing at a specific load. The mutual prints, which are reached under given corrections of the gearing, are simulated by a practical test. It is the simplest way of practically evaluating the correct grip of cogwheels. This process is used for analysing the problematic gear. Based on the results of this test, it is possible to establish the area of interest for new corrections of gearing which can help to reduce the noise level, improve the grip conditions or durability on the given gearing.