Search results for: tunneling space
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3674

Search results for: tunneling space

3644 Environmental and Space Travel

Authors: Alimohammad

Abstract:

Man's entry into space is one of the most important results of developments and advances made in information technology. But this human step, like many of his other actions, is not free of danger, as space pollution today has become a major problem for the global community. Paying attention to the issue of preserving the space environment is in the interest of all governments and mankind, and ignoring it can increase the possibility of conflict between countries. What many space powers still do not pay attention to is the freedom to explore and exploit space should be limited by banning pollution of the space environment. Therefore, freedom and prohibition are complementary and should not be considered conflicting concepts. The legal system created by the current space treaties for the effective preservation of the space environment has failed. Customary international law also does not have an effective provision and guarantee of sufficient executions in order to prevent damage to the environment. Considering the responsibility of each generation in the healthy transfer of the environment to the next generation and considering the sustainable development concept, the space environment must also be passed on to future generations in a healthy and undamaged manner. As a result, many environmental policies related to Earth should also be applied to the space environment..

Keywords: law, space, environment, responsibility

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3643 Double Negative Differential Resistance Features in Series AIN/GaN Double-Barrier Resonant Tunneling Diodes Vertically Integrated by Plasma-Assisted Molecular Beam Epitaxy

Authors: Jiajia Yao, Guanlin Wu, Fang Liu, Junshuai Xue, Yue Hao

Abstract:

This study reports on the epitaxial growth of a GaN-based resonant tunneling diode (RTD) structure with stable and repeatable double negative differential resistance (NDR) characteristics at room temperature on a c-plane GaN-on-sapphire template using plasma-assisted molecular beam epitaxy (PA-MBE) technology. In this structure, two independent AlN/GaN RTDs are epitaxially connected in series in the vertical growth direction through a silicon-doped GaN layer. As the collector electrode bias voltage increases, the two RTDs respectively align the ground state energy level in the quantum well with the 2DEG energy level in the emitter accumulation well to achieve quantum resonant tunneling and then reach the negative differential resistance (NDR) region. The two NDR regions exhibit similar peak current densities and peak-to-valley current ratios, which are 230 kA/cm² and 249 kA/cm², 1.33 and 1.38, respectively, for a device with a collector electrode mesa diameter of 1 µm. The consistency of the NDR is much higher than the results of on-chip discrete RTD device interconnection, resulting from the smaller chip area, fewer interconnect parasitic parameters, and less process complexity. The methods and results presented in this paper show the brilliant prospects of GaN RTDs in the development of multi-value logic digital circuits.

Keywords: MBE, AlN/GaN, RTDs, double NDR

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3642 Computation of ΔV Requirements for Space Debris Removal Using Orbital Transfer

Authors: Sadhvi Gupta, Charulatha S.

Abstract:

Since the dawn of the early 1950s humans have launched numerous vehicles in space. Be it from rockets to rovers humans have done tremendous growth in the technology sector. While there is mostly upside for it for humans the only major downside which cannot be ignored now is the amount of junk produced in space due to it i.e. space debris. All this space junk amounts from objects we launch from earth which so remains in orbit until it re-enters the atmosphere. Space debris can be of various sizes mainly the big ones are of the dead satellites floating in space and small ones can consist of various things like paint flecks, screwdrivers, bolts etc. Tracking of small space debris whose size is less than 10 cm is impossible and can have vast implications. As the amount of space debris increases in space the chances of it hitting a functional satellite also increases. And it is extremely costly to repair or recover the satellite once hit by a revolving space debris. So the proposed solution is, Actively removing space debris while keeping space sustainability in mind. For this solution a total of 8 modules will be launched in LEO and in GEO and these models will be placed in their desired orbits through Hohmann transfer and for that calculating ΔV values is crucial. After which the modules will be placed in their designated positions in STK software and thorough analysis is conducted.

Keywords: space debris, Hohmann transfer, STK, delta-V

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3641 Need of National Space Legislation for Space Faring Nations

Authors: Muhammad Naveed, Yang Caixia

Abstract:

The need for national space legislation is pivotal, particularly in light of the fact that in recent years space activities have grown immensely both in volume and diversity. Countries are progressively developing capabilities in space exploration and scientific discoveries, market their capabilities to manufacture satellites, provide launch services from their facilities and are looking to privatize and commercialize their space resources. Today, nations are also seeking to comprehend the technological and financial potential of the private sector and are considering to share their financial burdens with them and to limit their exposures to risks, but they are lagging behind in legal framework in this regard. In the perspective of these emerging developments, it is therefore, felt that national space legislation should be enacted with the goal of building and implementing a vibrant and transparent legal framework at the national level to hasten investments and to ensure growth in this capital intensive - highly yield strategic sector. This study looks at (I) the international legal framework that governs space activities; (II) motivation behind making national space laws; and (III) the need for national space legislation. The paper concludes with some recommendations with regards to the conceivable future direction for national space legislation, in particular space empowered sub-areas for countries.

Keywords: international conventions, national legislation, space faring nations, space law

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3640 The Effects of Ethnicity, Personality and Religiosity on Desire for Personal Space

Authors: Ioanna Skoura

Abstract:

Past research shows that personal space has been investigated since the 1950s. Also, personality traits have been found to have a significant relationship with personal space. However, some of these studies have been criticized for being ethically inappropriate. In an attempt to avoid ethical issues, a new scale measuring desire for personal space has been created. The purpose of the present study is to investigate the impact of ethnicity on desire for personal space. Additionally, extraversion and neuroticism are expected to predict significantly desire for personal space. Furthermore, the study is looking for any impact of religiosity on desire for personal space. In order to test the previous hypotheses, 115 participants from three cultural groups (English, Greeks in Greece and Greeks in the UK) are recruited online. Results indicate that only extraversion and religiosity are significant predictors of desire for personal space. Implications of the findings are discussed and suggestions for future research are made.

Keywords: ethnicity, religiosity, personality, personal space

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3639 Investigation of the Effect of Excavation Step in NATM on Surface Settlement by Finite Element Method

Authors: Seyed Mehrdad Gholami

Abstract:

Nowadays, using rail transport system (Metro) is increased in most cities of The world, so the need for safe and economical way of building tunnels and subway stations is felt more and more. One of the most commonly used methods for constructing underground structures in urban areas is NATM (New Austrian tunneling method). In this method, there are some key parameters such as excavation steps and cross-sectional area that have a significant effect on the surface settlement. Settlement is a very important control factor related to safe excavation. In this paper, Finite Element Method is used by Abaqus. R6 station of Tehran Metro Line 6 is built by NATM and the construction of that is studied and analyzed. Considering the outcomes obtained from numerical modeling and comparison with the results of the instrumentation and monitoring of field, finally, the excavation step of 1 meter and longitudinal distance of 14 meters between side drifts is suggested to achieve safe tunneling with allowable settlement.

Keywords: excavation step, NATM, numerical modeling, settlement.

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3638 Finite Element Analysis of the Drive Shaft and Jacking Frame Interaction in Micro-Tunneling Method: Case Study of Tehran Sewerage

Authors: B. Mohammadi, A. Riazati, P. Soltan Sanjari, S. Azimbeik

Abstract:

The ever-increasing development of civic demands on one hand; and the urban constrains for newly establish of infrastructures, on the other hand, perforce the engineering committees to apply non-conflicting methods in order to optimize the results. One of these optimized procedures to establish the main sewerage networks is the pipe jacking and micro-tunneling method. The raw information and researches are based on the experiments of the slurry micro-tunneling project of the Tehran main sewerage network that it has executed by the KAYSON co. The 4985 meters route of the mentioned project that is located nearby the Azadi square and the most vital arteries of Tehran is faced to 45% physical progress nowadays. The boring machine is made by the Herrenknecht and the diameter of the using concrete-polymer pipes are 1600 and 1800 millimeters. Placing and excavating several shafts on the ground and direct Tunnel boring between the axes of issued shafts is one of the requirements of the micro-tunneling. Considering the stream of the ground located shafts should care the hydraulic circumstances, civic conditions, site geography, traffic cautions and etc. The profile length has to convert to many shortened segment lines so the generated angle between the segments will be based in the manhole centers. Each segment line between two continues drive and receive the shaft, displays the jack location, driving angle and the path straight, thus, the diversity of issued angle causes the variety of jack positioning in the shaft. The jacking frame fixing conditions and it's associated dynamic load direction produces various patterns of Stress and Strain distribution and creating fatigues in the shaft wall and the soil surrounded the shaft. This pattern diversification makes the shaft wall transformed, unbalanced subsidence and alteration in the pipe jacking Stress Contour. This research is based on experiments of the Tehran's west sewerage plan and the numerical analysis the interaction of the soil around the shaft, shaft walls and the Jacking frame direction and finally, the suitable or unsuitable location of the pipe jacking shaft will be determined.

Keywords: underground structure, micro-tunneling, fatigue analysis, dynamic-soil–structure interaction, underground water, finite element analysis

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3637 An Alternative Rectangular Tunnels to Conventional Twin Circular Bored Tunnels in Weak Ground Conditions

Authors: Alex Atanaw Alebachew

Abstract:

The outcomes of a numerical research study conducted using the PLAXIS software to analyze surface settlements and moments generated in tunnel linings. The investigation focuses on both circular and rectangular twin tunnels. The study suggests that rectangular tunnels, although considered unconventional in modern tunneling practices, may be a viable option for shallow-depth tunneling in weak ground. The recommendation for engineers in the tunneling industry is to consider the use of rectangular tunnel boring machines (TBMs) based on the findings of this analysis. The research emphasizes the importance of evaluating various tunneling methods to optimize performance and address specific challenges in different ground conditions. These findings provide valuable insights into the behavior of rectangular tunnels compared to circular tunnels, emphasizing factors such as burial depth, relative positioning, tunnel size, and critical distance that influence surface settlements and bending moments. This research explores the feasibility of utilizing rectangular Tunnel Boring Machines (TBMs) as an alternative to conventional circular TBMs. The research findings indicate that rectangular tunnels exhibit slightly lower settlement than circular tunnels at shallow depths, especially in a narrower range directly above the twin tunnels. This difference could be attributed to maintaining a consistent tunnel-lining thickness across all depths. In deeper tunnel scenarios, circular tunnels experience less settlement compared to rectangular tunnels. Additionally, parallel rectangular tunnels settle more gradually than piggyback configurations, while piggyback tunnels show increased moments in the tunnel built second at the same level. Both settlement and moment coefficients increase with the diameter of twin tunnels, irrespective of their shape. The critical distance for both circular and rectangular tunnels is around 2.5 times the tunnel diameter, and distances closer than this result in a notable increase in moments. Rectangular tunnels spaced closer than 5 times the diameter led to higher settlement, and circular tunnels spaced closer than 2.5 to 3 times the diameter experience increased settlement as well.

Keywords: alternative, rectangular, tunnel, twin bored circular, weak ground

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3636 Analysis on the Development and Evolution of China’s Territorial Spatial Planning

Authors: He YuanYan

Abstract:

In recent years, China has implemented the reform of land and space planning. As an important public policy, land and space planning plays a vital role in the construction and development of cities. Land and space planning throughout the country is in full swing, but there are still many disputes from all walks of life. The content, scope, and specific implementation process of land and space planning are also ambiguous, leading to the integration of multiple regulation problems such as unclear authority, unclear responsibilities, and poor planning results during the implementation of land and space planning. Therefore, it is necessary to sort out the development and evolution of domestic and foreign land space planning, clarify the problems and cruxes from the current situation of China's land space planning, and sort out the obstacles and countermeasures to the implementation of this policy, so as to deepen the understanding of the connotation of land space planning. It is of great practical significance for all planners to correctly understand and clarify the specific contents and methods of land space planning and to smoothly promote the implementation of land space planning at all levels.

Keywords: territorial spatial planning, public policy, land space, overall planning

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3635 Research on Spatial Morphology and Protection of Traditional Rural Settlements Based on Space Syntax: Taking Xiazhuang Village and Shijia Village in Huzhou as Example

Authors: Shenpu Liu

Abstract:

Space syntax, a paradigm of the urban research, which manifests people’s intuitive and abstract perception of a material space with a solid mathematical way, explores how space represents its social characteristics. Taking Xiazhuang village and Shijia Village in Huzhou as an example and focusing on inward structure and street space, this article recognizes the connotative significance of the settlement with the aid of space syntax theory and quantitative analysis method from the perspective of spatial configuration to present relevant suggestions for its future planning and provides references for traditional rural settlement protection.

Keywords: Shijia village, space configuration, space syntax, traditional rural settlement, Xiazhuang village

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3634 Application of Micro-Tunneling Technique to Rectify Tilted Structures Constructed on Cohesive Soil

Authors: Yasser R. Tawfic, Mohamed A. Eid

Abstract:

Foundation differential settlement and supported structure tilting is an occasionally occurred engineering problem. This may be caused by overloading, changes in ground soil properties or unsupported nearby excavations. Engineering thinking points directly toward the logic solution for such problem by uplifting the settled side. This can be achieved with deep foundation elements such as micro-piles and macro-piles™, jacked piers and helical piers, jet grouted soil-crete columns, compaction grout columns, cement grouting or with chemical grouting, or traditional pit underpinning with concrete and mortar. Although, some of these techniques offer economic, fast and low noise solutions, many of them are quite the contrary. For tilted structures, with limited inclination, it may be much easier to cause a balancing settlement on the less-settlement side which shall be done carefully in a proper rate. This principal has been applied in Leaning Tower of Pisa stabilization with soil extraction from the ground surface. In this research, the authors attempt to introduce a new solution with a different point of view. So, micro-tunneling technique is presented in here as an intended ground deformation cause. In general, micro-tunneling is expected to induce limited ground deformations. Thus, the researchers propose to apply the technique to form small size ground unsupported holes to produce the target deformations. This shall be done in four phases: •Application of one or more micro-tunnels, regarding the existing differential settlement value, under the raised side of the tilted structure. •For each individual tunnel, the lining shall be pulled out from both sides (from jacking and receiving shafts) in slow rate. •If required, according to calculations and site records, an additional surface load can be applied on the raised foundation side. •Finally, a strengthening soil grouting shall be applied for stabilization after adjustment. A finite element based numerical model is presented to simulate the proposed construction phases for different tunneling positions and tunnels group. For each case, the surface settlements are calculated and induced plasticity points are checked. These results show the impact of the suggested procedure on the tilted structure and its feasibility. Comparing results also show the importance of the position selection and tunnels group gradual effect. Thus, a new engineering solution is presented to one of the structural and geotechnical engineering challenges.

Keywords: differential settlement, micro-tunneling, soil-structure interaction, tilted structures

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3633 Topological Quantum Diffeomorphisms in Field Theory and the Spectrum of the Space-Time

Authors: Francisco Bulnes

Abstract:

Through the Fukaya conjecture and the wrapped Floer cohomology, the correspondences between paths in a loop space and states of a wrapping space of states in a Hamiltonian space (the ramification of field in this case is the connection to the operator that goes from TM to T*M) are demonstrated where these last states are corresponding to bosonic extensions of a spectrum of the space-time or direct image of the functor Spec, on space-time. This establishes a distinguished diffeomorphism defined by the mapping from the corresponding loops space to wrapping category of the Floer cohomology complex which furthermore relates in certain proportion D-branes (certain D-modules) with strings. This also gives to place to certain conjecture that establishes equivalences between moduli spaces that can be consigned in a moduli identity taking as space-time the Hitchin moduli space on G, whose dual can be expressed by a factor of a bosonic moduli spaces.

Keywords: Floer cohomology, Fukaya conjecture, Lagrangian submanifolds, quantum topological diffeomorphism

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3632 Space Debris: An Environmental Hazard

Authors: Anwesha Pathak

Abstract:

Space law refers to all legal provisions that may regulate or apply to space travel, as well as to space-related activity. Although there is undoubtedly a core corpus of “space law,” rather than designating a conceptually distinct single kind of law, the phrase can be seen as a label applied to a bucket that includes a variety of different laws and regulations. Similar to ‘family law' or ‘environmental law' "space law" refers to a variety of laws that are identified by the subject matter they address rather than by the logical extension of a single legal concept. The word "space law" refers to the Law of Space, which can cover anything from the specifics of an insurance agreement for a specific space launch to the most general guidelines that direct state behaviour in space. Space debris, often referred to as space junk, space pollution, space waste, space trash, or space garbage, is a term used to describe abandoned human-made objects in space, primarily in Earth orbit. These include disused spacecraft, discarded launch vehicle stages, mission-related detritus, and fragmentation material from the destruction of disused rocket bodies and spacecraft, which is particularly prevalent in Earth orbit. Other types of space debris, besides abandoned human-made objects in orbit, include pieces left over from collisions, erosion, and disintegration, or even paint specks, solidified liquids ejected from spacecraft, and unburned components from solid rocket engines. The initial action of launching or using a spacecraft in near-Earth orbit imposes an external cost on others that is typically not taken into account or fully accounted for in the cost by the launcher or payload owner.

Keywords: space, outer space treaty, geostationary orbit, satellites, spacecrafts

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3631 A Study of Algebraic Structure Involving Banach Space through Q-Analogue

Authors: Abdul Hakim Khan

Abstract:

The aim of the present paper is to study the Banach Space and Combinatorial Algebraic Structure of R. It is further aimed to study algebraic structure of set of all q-extension of classical formula and function for 0 < q < 1.

Keywords: integral functions, q-extensions, q numbers of metric space, algebraic structure of r and banach space

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3630 The Identity of the Cairene Public Space: Manifestations of Social and Architectural Heritage in the City Square of Medieval Cairo

Authors: Muhammad Emad Feteha

Abstract:

Cairo has been famous for the unique identity of its medieval architecture, which was formed by multiple dynasties that ruled Egypt. However, only a few researches were done on the identity of its public space. This paper links both the architectural and the socio-political aspects of the Cairene public space and studies how they affected each other. The subject of the study is Maydan Salah al-Din, the main city square of medieval Cairo, which reveals a quite useful information, not only about the architectural identity of the Cairene public space but also about the socio-political patterns that operated within. The analytical framework is based on Lefebvre’s theory, the ‘production of space’, in which he applied 'the Hegelian dialectic' in order to understand how the social practice forms the space, and how, in turn, the space forms the social practice. This framework offers a comprehensive understanding of the identity of the Cairene public space, which does not separate architecture from the social practice.

Keywords: architectural identity, Cairene public space, Islamic architectural history, production of space

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3629 Digital Transformation as the Subject of the Knowledge Model of the Discursive Space

Authors: Rafal Maciag

Abstract:

Due to the development of the current civilization, one must create suitable models of its pervasive massive phenomena. Such a phenomenon is the digital transformation, which has a substantial number of disciplined, methodical interpretations forming the diversified reflection. This reflection could be understood pragmatically as the current temporal, a local differential state of knowledge. The model of the discursive space is proposed as a model for the analysis and description of this knowledge. Discursive space is understood as an autonomous multidimensional space where separate discourses traverse specific trajectories of what can be presented in multidimensional parallel coordinate system. Discursive space built on the world of facts preserves the complex character of that world. Digital transformation as a discursive space has a relativistic character that means that at the same time, it is created by the dynamic discourses and these discourses are molded by the shape of this space.

Keywords: complexity, digital transformation, discourse, discursive space, knowledge

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3628 The Control System Architecture of Space Environment Simulator

Authors: Zhan Haiyang, Gu Miao

Abstract:

This article mainly introduces the control system architecture of space environment simulator, simultaneously also briefly introduce the automation control technology of industrial process and the measurement technology of vacuum and cold black environment. According to the volume of chamber, the space environment simulator is divided into three types of small, medium and large. According to the classification and application of space environment simulator, the control system is divided into the control system of small, medium, large space environment simulator and the centralized control system of multiple space environment simulators.

Keywords: space environment simulator, control system, architecture, automation control technology

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3627 The Necessity to Standardize Procedures of Providing Engineering Geological Data for Designing Road and Railway Tunneling Projects

Authors: Atefeh Saljooghi Khoshkar, Jafar Hassanpour

Abstract:

One of the main problems of the design stage relating to many tunneling projects is the lack of an appropriate standard for the provision of engineering geological data in a predefined format. In particular, this is more reflected in highway and railroad tunnel projects in which there is a number of tunnels and different professional teams involved. In this regard, comprehensive software needs to be designed using the accepted methods in order to help engineering geologists to prepare standard reports, which contain sufficient input data for the design stage. Regarding this necessity, applied software has been designed using macro capabilities and Visual Basic programming language (VBA) through Microsoft Excel. In this software, all of the engineering geological input data, which are required for designing different parts of tunnels, such as discontinuities properties, rock mass strength parameters, rock mass classification systems, boreability classification, the penetration rate, and so forth, can be calculated and reported in a standard format.

Keywords: engineering geology, rock mass classification, rock mechanic, tunnel

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3626 A Proposal for U-City (Smart City) Service Method Using Real-Time Digital Map

Authors: SangWon Han, MuWook Pyeon, Sujung Moon, DaeKyo Seo

Abstract:

Recently, technologies based on three-dimensional (3D) space information are being developed and quality of life is improving as a result. Research on real-time digital map (RDM) is being conducted now to provide 3D space information. RDM is a service that creates and supplies 3D space information in real time based on location/shape detection. Research subjects on RDM include the construction of 3D space information with matching image data, complementing the weaknesses of image acquisition using multi-source data, and data collection methods using big data. Using RDM will be effective for space analysis using 3D space information in a U-City and for other space information utilization technologies.

Keywords: RDM, multi-source data, big data, U-City

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3625 Tailoring Quantum Oscillations of Excitonic Schrodinger’s Cats as Qubits

Authors: Amit Bhunia, Mohit Kumar Singh, Maryam Al Huwayz, Mohamed Henini, Shouvik Datta

Abstract:

We report [https://arxiv.org/abs/2107.13518] experimental detection and control of Schrodinger’s Cat like macroscopically large, quantum coherent state of a two-component Bose-Einstein condensate of spatially indirect electron-hole pairs or excitons using a resonant tunneling diode of III-V Semiconductors. This provides access to millions of excitons as qubits to allow efficient, fault-tolerant quantum computation. In this work, we measure phase-coherent periodic oscillations in photo-generated capacitance as a function of an applied voltage bias and light intensity over a macroscopically large area. Periodic presence and absence of splitting of excitonic peaks in the optical spectra measured by photocapacitance point towards tunneling induced variations in capacitive coupling between the quantum well and quantum dots. Observation of negative ‘quantum capacitance’ due to a screening of charge carriers by the quantum well indicates Coulomb correlations of interacting excitons in the plane of the sample. We also establish that coherent resonant tunneling in this well-dot heterostructure restricts the available momentum space of the charge carriers within this quantum well. Consequently, the electric polarization vector of the associated indirect excitons collective orients along the direction of applied bias and these excitons undergo Bose-Einstein condensation below ~100 K. Generation of interference beats in photocapacitance oscillation even with incoherent white light further confirm the presence of stable, long-range spatial correlation among these indirect excitons. We finally demonstrate collective Rabi oscillations of these macroscopically large, ‘multipartite’, two-level, coupled and uncoupled quantum states of excitonic condensate as qubits. Therefore, our study not only brings the physics and technology of Bose-Einstein condensation within the reaches of semiconductor chips but also opens up experimental investigations of the fundamentals of quantum physics using similar techniques. Operational temperatures of such two-component excitonic BEC can be raised further with a more densely packed, ordered array of QDs and/or using materials having larger excitonic binding energies. However, fabrications of single crystals of 0D-2D heterostructures using 2D materials (e.g. transition metal di-chalcogenides, oxides, perovskites etc.) having higher excitonic binding energies are still an open challenge for semiconductor optoelectronics. As of now, these 0D-2D heterostructures can already be scaled up for mass production of miniaturized, portable quantum optoelectronic devices using the existing III-V and/or Nitride based semiconductor fabrication technologies.

Keywords: exciton, Bose-Einstein condensation, quantum computation, heterostructures, semiconductor Physics, quantum fluids, Schrodinger's Cat

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3624 Friendly Public Spaces in Iran

Authors: Bibi Somayeh Aliakbari, Niknaz Kachooei, Fatemeh Amiri Najafabadi

Abstract:

According to the results of contemporary urbanism, social living moved into buildings and the quality of urban space has been declining. But still, there are life in open public space and it is one of reason attendance and activities of people in open public spaces.The purpose of this research is finding reason creation friendly public space in urban spaces and also use these in new urban spaces.The research methodology consisted of a qualitative model based on observation and graphical analysis. In this paper case study is public space historical, moderns in urban scales and local scales in Iran.This paper shows that Existence of friendly public space in cities cause is attendance and activities of people in open public spaces that it is reason the revitalization of public open spaces in cities.

Keywords: public space, public open space, friendly public space, Iran

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3623 Active Space Debris Removal by Extreme Ultraviolet Radiation

Authors: A. Anandha Selvan, B. Malarvizhi

Abstract:

In recent year the problem of space debris have become very serious. The mass of the artificial objects in orbit increased quite steadily at the rate of about 145 metric tons annually, leading to a total tally of approximately 7000 metric tons. Now most of space debris object orbiting in LEO region about 97%. The catastrophic collision can be mostly occurred in LEO region, where this collision generate the new debris. Thus, we propose a concept for cleaning the space debris in the region of thermosphere by passing the Extreme Ultraviolet (EUV) radiation to in front of space debris object from the re-orbiter. So in our concept the Extreme Ultraviolet (EUV) radiation will create the thermosphere expansion by reacting with atmospheric gas particles. So the drag is produced in front of the space debris object by thermosphere expansion. This drag force is high enough to slow down the space debris object’s relative velocity. Therefore the space debris object gradually reducing the altitude and finally enter into the earth’s atmosphere. After the first target is removed, the re-orbiter can be goes into next target. This method remove the space debris object without catching debris object. Thus it can be applied to a wide range of debris object without regard to their shapes or rotation. This paper discusses the operation of re-orbiter for removing the space debris in thermosphere region.

Keywords: active space debris removal, space debris, LEO, extreme ultraviolet, re-orbiter, thermosphere

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3622 India and Space Insurance Policy: An Analytical Insight

Authors: Shreyas Jayasimha, Suneel Anand Sundharesan, Rohan Tigadi

Abstract:

In the recent past, the United States of America and Russia were the only two dominant players in the field of space exploration and had a virtual monopoly in the field of space and technology. However, this has changed over the past few years. Many other nation states such as India, China, and the UK have made significant progress in this field. Amongst these nations, the growth and development of the Indian space program have been nothing short of a miracle. Starting recently, India has successfully launched a series of satellites including its much acclaimed Mangalyaan mission, which placed a satellite in Mars’ orbit. The fact that India was able to attain this feat in its attempt demonstrates the enormous growth potential and promise that the Indian space program holds for the coming years. However, unlike other space-faring nations, India does not have a comprehensive and consolidated space insurance policy. In this regard, it is pertinent to note that, the costs and risks involved in a administering a space program are enormous. Therefore, in the absence of a comprehensive space insurance policy, any losses from an unsuccessful will have to be borne by the state exchequer. Thus, in order to ensure that Indian space program continues on its upward trajectory, the Indian establishment should seriously consider formulating a comprehensive insurance policy. This paper intends to analyze the international best practices followed by other space-faring nations in relation to space insurance policy. Thereafter, the authors seek to examine the current regime in India relating to space insurance policy. Finally, the authors will conclude by providing a series of recommendations regarding the essential elements that should be part of any Indian space insurance policy regime.

Keywords: India, space insurance policy, space law, Indian space research organization

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3621 On Boundary Values of Hardy Space Banach Space-Valued Functions

Authors: Irina Peterburgsky

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Let T be a unit circumference of a complex plane, E be a Banach space, E* and E** be its conjugate and second conjugate, respectively. In general, a Hardy space Hp(E), p ≥1, where functions act from the open unit disk to E, could contain a function for which even weak nontangential (angular) boundary value in the space E** does not exist at any point of the unit circumference T (C. Grossetete.) The situation is "better" when certain restrictions to the Banach space of values are applied (more or less resembling a classical case of scalar-valued functions depending on constrains, as shown by R. Ryan.) This paper shows that, nevertheless, in the case of a Banach space of a general type, the following positive statement is true: Proposition. For any function f(z) from Hp(E), p ≥ 1, there exists a function F(eiθ) on the unit circumference T to E** whose Poisson (in the Pettis sense) is integral regains the function f(z) on the open unit disk. Some characteristics of the function F(eiθ) are demonstrated.

Keywords: hardy spaces, Banach space-valued function, boundary values, Pettis integral

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3620 Legal and Contractual Framework for Private Experiments in Space

Authors: Linda Ana-Maria Ungureanu

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As space exploration opens to new actors, we are faced with the interesting question of regulating more complex structures that enable private experiments. From intellectual property implications to private and public law, there is a multitude of factors and legal structures that need to be taken into consideration when opening space, and these structures need to be harmonized with the International Space Treaties governing space exploration. In this sense, this article presents an overview of the legal and contractual framework applicable to private experiments conducted in space and/or in relation to off-world environments. Additionally, the article analyses the manner in which national space agencies regulate agreements concluded with private actors and research institutions. Finally, the article sets a series of de lege ferenda proposals for the regulation of general research and development rules and intellectual property matters that are connected to experiments and research conducted in space and/or concerning off-world environments.

Keywords: private space, intellectual property, contracts, ESA guidelines, EU legislation, Intellectual property law, international IP treaties

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3619 The Position of Space weather in Africa-Education and Outreach

Authors: Babagana Abubakar, Alhaji Kuya

Abstract:

Although the field of Space weather science is a young field among the space sciences, but yet history has it that activities related to this science began since the year 1859 when the great solar storm happened which resulted in the disruptions of telegraphs operations around the World at that particular time subsequently making it possible for the scientist Richard Carrington to be able to connect the Solar flare observed a day earlier before the great storm and the great deflection of the Earth’s Magnetic field (geometric storm) simultaneous with the telegraph disruption. However years later as at today with the advent of and the coming into existence of the Explorer 1, the Luna 1 and the establishments of the United States International Space Weather Program, International Geophysical Year (IGY) as well as the International Center for Space Weather Sciences and Education (ICSWSE) have made us understand the Space weather better and enable us well define the field of Space weather science. Despite the successes recorded in the development of Space sciences as a whole over the last century and the coming onboard of specialized bodies/programs on space weather like the International Space Weather Program and the ICSWSE, the majority of Africans including institutions, research organizations and even some governments are still ignorant about the existence of theSpace weather science,because apart from some very few countries like South Africa, Nigeria and Egypt among some few others the majority of the African nations and their academic institutions have no knowledge or idea about the existence of this field of Space science (Space weather).

Keywords: Africa, space, weather, education, science

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3618 Structural Analysis on the Composition of Video Game Virtual Spaces

Authors: Qin Luofeng, Shen Siqi

Abstract:

For the 58 years since the first video game came into being, the video game industry is getting through an explosive evolution from then on. Video games exert great influence on society and become a reflection of public life to some extent. Video game virtual spaces are where activities are taking place like real spaces. And that’s the reason why some architects pay attention to video games. However, compared to the researches on the appearance of games, we observe a lack of theoretical comprehensive on the construction of video game virtual spaces. The research method of this paper is to collect literature and conduct theoretical research about the virtual space in video games firstly. And then analogizing the opinions on the space phenomena from the theory of literature and films. Finally, this paper proposes a three-layer framework for the construction of video game virtual spaces: “algorithmic space-narrative space players space”, which correspond to the exterior, expressive, affective parts of the game space. Also, we illustrate each sub-space according to numerous instances of published video games. Hoping this writing could promote the interactive development of video games and architecture.

Keywords: video game, virtual space, narrativity, social space, emotional connection

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3617 Classification of Traffic Complex Acoustic Space

Authors: Bin Wang, Jian Kang

Abstract:

After years of development, the study of soundscape has been refined to the types of urban space and building. Traffic complex takes traffic function as the core, with obvious design features of architectural space combination and traffic streamline. The acoustic environment is strongly characterized by function, space, material, user and other factors. Traffic complex integrates various functions of business, accommodation, entertainment and so on. It has various forms, complex and varied experiences, and its acoustic environment is turned rich and interesting with distribution and coordination of various functions, division and unification of the mass, separation and organization of different space and the cross and the integration of multiple traffic flow. In this study, it made field recordings of each space of various traffic complex, and extracted and analyzed different acoustic elements, including changes in sound pressure, frequency distribution, steady sound source, sound source information and other aspects, to make cluster analysis of each independent traffic complex buildings. It divided complicated traffic complex building space into several typical sound space from acoustic environment perspective, mainly including stable sound space, high-pressure sound space, rhythm sound space and upheaval sound space. This classification can further deepen the study of subjective evaluation and control of the acoustic environment of traffic complex.

Keywords: soundscape, traffic complex, cluster analysis, classification

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3616 Identification of Configuration Space Singularities with Local Real Algebraic Geometry

Authors: Marc Diesse, Hochschule Heilbronn

Abstract:

We address the question of identifying the configuration space singularities of linkages, i.e., points where the configuration space is not locally a submanifold of Euclidean space. Because the configuration space cannot be smoothly parameterized at such points, these singularity types have a significantly negative impact on the kinematics of the linkage. It is known that Jacobian methods do not provide sufficient conditions for the existence of CS-singularities. Herein, we present several additional algebraic criteria that provide the sufficient conditions. Further, we use those criteria to analyze certain classes of planar linkages. These examples will also show how the presented criteria can be checked using algorithmic methods.

Keywords: linkages, configuration space-singularities, real algebraic geometry, analytic geometry

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3615 Characterization of Self-Assembly Behavior of 1-Dodecylamine Molecules on Au (111) Surface

Authors: Wan-Tzu Yen, Yu-Chen Luo, I-Ping Liu, Po-Hsuan Yeh, Sheng-Hsun Fu, Yuh-Lang Lee

Abstract:

Self-assembled characteristics and adsorption performance of 1-dodecylamine molecules on gold (Au) (111) surfaces were characterized via cyclic voltammetry (CV), surface-enhanced infrared absorption spectroscopy (SEIRAS) and scanning tunneling microscopy (STM). The present study focused on the formation of 1-dodecylamine (DDA) on a gold surface with respect to the ex-situ arrangement of an adlayer on the Au(111) surface, and phase transition at potential dynamics carried out by EC-STM. This study reveals that alkyl amine molecules were formed an adsorption pattern with highly regular “lie down shape” on Au(111) surface, even in an extreme acid system (pH = 1). Acidic electrolyte (HClO₄) could protonate the surface of alkyl amine of a monolayer of the gold surface when potential shifts to negative. The quite stability of 1-dodecylamine on the gold surface maintained the monolayer across the potential window (0.1-0.8V). This transform model was confirmed by EC-STM. In addition, amine-modified Au(111) electrode adlayer used to examine how to affect an electron transfer across an interface using [Fe(CN)₆]³⁻/[Fe(CN)₆]⁴⁻ redox pair containing 0.1 M HClO₄ solution.

Keywords: cyclic voltammetry, dodecylamine, gold (Au)(111), scanning tunneling microscopy, self-assembled monolayer, surface-enhanced infrared absorption spectroscopy

Procedia PDF Downloads 161