Search results for: space communications
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4096

Search results for: space communications

3796 A Model for Optimizing Inventory Replenishment and Shelf Space Management in Retail Industries

Authors: Nermine A. Harraz, Aliaa Abouali

Abstract:

The retail stores put up for sale multiple items while the spaces in the backroom and display areas constitute a scarce resource. Availability, volume, and location of the product displayed in the showroom influence the customer’s demand. Managing these operations individually will result in sub-optimal overall retail store’s profit; therefore, a non-linear integer programming model (NLIP) is developed to determine the inventory replenishment and shelf space allocation decisions that together maximize the retailer’s profit under shelf space and backroom storage constraints taking into consideration that the demand rate is positively dependent on the amount and location of items displayed in the showroom. The developed model is solved using LINGO® software. The NLIP model is implemented in a real world case study in a large retail outlet providing a large variety of products. The proposed model is validated and shows logical results when using the experimental data collected from the market.

Keywords: retailing management, inventory replenishment, shelf space allocation, showroom, backroom

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3795 Technology and Terror

Authors: Janet D. Fish

Abstract:

This paper will analyze how advanced information technology communications platform’s such as you tube, twitter, Facebook, and websites are being used in marketing cultural diversity on a global scale. The scope of this topic will encompass the use of marketing terror as a tool of educational understanding, accepting, and incorporating other ethnic groups into extremist Islamic cultural practices with an end goal of cultural assimilation. This paper will examine the impacts of various influences, such as globalism and technology on common public values and cultural diversity. Additionally, multiculturalism in public administration settings will be examined across cultures. Communications are a primary focus of review for this paper, the purpose of this review is to see how different technological platforms are currently being used as major tools of influence within the public sector. Technology and terror must become a primary concern for new public administrators in a modern world. While its existence is acknowledged, boundaries of legal recourse are currently few. Public administrators must understand the depth and reach of the future consequences of an unchecked process in the realm of technology and terror on a global scale.

Keywords: inclusionism, exclusionism, technology, terror

Procedia PDF Downloads 356
3794 Finding the Optimal Meeting Point Based on Travel Plans in Road Networks

Authors: Mohammad H. Ahmadi, Vahid Haghighatdoost

Abstract:

Given a set of source locations for a group of friends, and a set of trip plans for each group member as a sequence of Categories-of-Interests (COIs) (e.g., restaurant), and finally a specific COI as a common destination that all group members will gather together, in Meeting Point Based on Trip Plans (MPTPs) queries our goal is to find a Point-of-Interest (POI) from different COIs, such that the aggregate travel distance for the group is minimized. In this work, we considered two cases for aggregate function as Sum and Max. For solving this query, we propose an efficient pruning technique for shrinking the search space. Our approach contains three steps. In the first step, it prunes the search space around the source locations. In the second step, it prunes the search space around the centroid of source locations. Finally, we compute the intersection of all pruned areas as the final refined search space. We prove that the POIs beyond the refined area cannot be part of optimal answer set. The paper also covers an extensive performance study of the proposed technique.

Keywords: meeting point, trip plans, road networks, spatial databases

Procedia PDF Downloads 155
3793 Relay Node Selection Algorithm for Cooperative Communications in Wireless Networks

Authors: Sunmyeng Kim

Abstract:

IEEE 802.11a/b/g standards support multiple transmission rates. Even though the use of multiple transmission rates increase the WLAN capacity, this feature leads to the performance anomaly problem. Cooperative communication was introduced to relieve the performance anomaly problem. Data packets are delivered to the destination much faster through a relay node with high rate than through direct transmission to the destination at low rate. In the legacy cooperative protocols, a source node chooses a relay node only based on the transmission rate. Therefore, they are not so feasible in multi-flow environments since they do not consider the effect of other flows. To alleviate the effect, we propose a new relay node selection algorithm based on the transmission rate and channel contention level. Performance evaluation is conducted using simulation, and shows that the proposed protocol significantly outperforms the previous protocol in terms of throughput and delay.

Keywords: cooperative communications, MAC protocol, relay node, WLAN

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3792 Dual-Polarized Multi-Antenna System for Massive MIMO Cellular Communications

Authors: Naser Ojaroudi Parchin, Haleh Jahanbakhsh Basherlou, Raed A. Abd-Alhameed, Peter S. Excell

Abstract:

In this paper, a multiple-input/multiple-output (MIMO) antenna design with polarization and radiation pattern diversity is presented for future smartphones. The configuration of the design consists of four double-fed circular-ring antenna elements located at different edges of the printed circuit board (PCB) with an FR-4 substrate and overall dimension of 75×150 mm2. The antenna elements are fed by 50-Ohm microstrip-lines and provide polarization and radiation pattern diversity function due to the orthogonal placement of their feed lines. A good impedance bandwidth (S11 ≤ -10 dB) of 3.4-3.8 GHz has been obtained for the smartphone antenna array. However, for S11 ≤ -6 dB, this value is 3.25-3.95 GHz. More than 3 dB realized gain and 80% total efficiency are achieved for the single-element radiator. The presented design not only provides the required radiation coverage but also generates the polarization diversity characteristic.

Keywords: cellular communications, multiple-input/multiple-output systems, mobile-phone antenna, polarization diversity

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3791 Interaction between Space Syntax and Agent-Based Approaches for Vehicle Volume Modelling

Authors: Chuan Yang, Jing Bie, Panagiotis Psimoulis, Zhong Wang

Abstract:

Modelling and understanding vehicle volume distribution over the urban network are essential for urban design and transport planning. The space syntax approach was widely applied as the main conceptual and methodological framework for contemporary vehicle volume models with the help of the statistical method of multiple regression analysis (MRA). However, the MRA model with space syntax variables shows a limitation in vehicle volume predicting in accounting for the crossed effect of the urban configurational characters and socio-economic factors. The aim of this paper is to construct models by interacting with the combined impact of the street network structure and socio-economic factors. In this paper, we present a multilevel linear (ML) and an agent-based (AB) vehicle volume model at an urban scale interacting with space syntax theoretical framework. The ML model allowed random effects of urban configurational characteristics in different urban contexts. And the AB model was developed with the incorporation of transformed space syntax components of the MRA models into the agents’ spatial behaviour. Three models were implemented in the same urban environment. The ML model exhibit superiority over the original MRA model in identifying the relative impacts of the configurational characters and macro-scale socio-economic factors that shape vehicle movement distribution over the city. Compared with the ML model, the suggested AB model represented the ability to estimate vehicle volume in the urban network considering the combined effects of configurational characters and land-use patterns at the street segment level.

Keywords: space syntax, vehicle volume modeling, multilevel model, agent-based model

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3790 The Effectiveness of Tehran Municipality's Transformation of a Metro Station into Pedestrian-Friendly Public Spaces

Authors: Homa Hedayat

Abstract:

Public spaces have been a central concern of urban planners for centuries but have been neglected for a long time. In the modernist planning, the focus has been on the requirements of cars rather than the needs and expectations of pedestrians, and therefore, cities have lost many qualities. Urban public space is a space within the city area which is accessible to all people and is the ground for their activity. People’s public life occurs in urban public spaces in a complex set of forms and functions. These spaces must facilitate diverse behavior, uses, and activities such as shopping, walking, conversation, entertainment, relaxation or even passing the time during festivities and events. One of the public spaces is the surrounding space of public transportation stations. Subway stations, although potentially encompass many different groups of people accommodate few social interactions. Making the surrounding areas of subway stations pedestrian-oriented, potentially increases the socialization capacity. The Sadeghieh Subway Station can be considered as the most important subway station in Tehran, which on the one hand is the rail port of Tehran's western entrance, and on the other is the port for railway journeys inside the city. The main concern of this study is to assess the success or failure of the interventions made by the municipality for changing the surrounding area of the Sadeghieh Subway Station into a pedestrian-oriented space and examine the amount of the area's improvement into a desirable space. The method used in this study is surveying, in which the data were collected using a questionnaire and interview. The study's population is all people who use Sadeghieh Subway, and the sample size for the study was 140 subjects. Using parametric one-sample t-test, we found improvement in factors such as transportation, security, pedestrian infrastructure, vitality and climate comfort. However, there was no improvement in mix use, recreational activity, readability.

Keywords: public space, public transportation stations, pedestrian-oriented space, socialization

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3789 Experimental Architectural Pedagogy: Discipline Space and Its Role in the Modern Teaching Identity

Authors: Matthew Armitt

Abstract:

The revolutionary school of architectural teaching – VKhUTEAMAS (1923-1926) was a new approach for a new society bringing architectural education to the masses and masses to the growing industrial production. The school's pedagogical contribution of the 1920s made it an important school of the modernist movement, engaging pedagogy as a mode of experimentation. The teachers and students saw design education not just as a process of knowledge transfer but as a vehicle for design innovation developing an approach without precedent. This process of teaching and learning served as a vehicle for venturing into the unknown through a discipline of architectural teaching called “Space” developed by the Soviet architect Nikolai Ladovskii (1881-1941). The creation of “Space” was paramount not only for its innovative pedagogy but also as an experimental laboratory for developing new architectural language. This paper discusses whether the historical teaching of “Space” can function in the construction of the modern teaching identity today to promote value, richness, quality, and diversity inherent in architectural design education. The history of “Space” teaching remains unknown within academic circles and separate from the current architectural teaching debate. Using VKhUTEMAS and the teaching of “Space” as a pedagogical lens and drawing upon research carried out in the Russian Federation, America, Canada, Germany, and the UK, this paper discusses how historically different models of teaching and learning can intersect through examining historical based educational research by exploring different design studio initiatives; pedagogical methodologies; teaching and learning theories and problem-based projects. There are strong arguments and desire for pedagogical change and this paper will promote new historical and educational research to widen the current academic debate by exposing new approaches to architectural teaching today.

Keywords: VKhUTEMAS, discipline space, modernist pedagogy, teaching identity

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3788 Correlation of Residential Community Layout and Neighborhood Relationship: A Morphological Analysis of Tainan Using Space Syntax

Authors: Ping-Hung Chen, Han-Liang Lin

Abstract:

Taiwan has formed diverse settlement patterns in different time and space backgrounds. Various socio-network links are created between individuals, families, communities, and societies, and different living cultures are also derived. But rapid urbanization and social structural change have caused the creation of densely-packed assembly housing complexes and made neighborhood community upward developed. This, among others, seemed to have affected neighborhood relationship and also created social problems. To understand the complex relations and socio-spatial structure of the community, it is important to use mixed methods. This research employs the theory of space syntax to analyze the layout and structural indicators of the selected communities in Tainan city. On the other hand, this research does the survey about residents' interactions and the sense of community by questionnaire of the selected communities. Then the mean values of the syntax measures from each community were correlated with the results of the questionnaire using a Pearson correlation to examine how elements in physical design affect the sense of community and neighborhood relationship. In Taiwan, most urban morphology research methods are qualitative study. This paper tries to use space syntax to find out the correlation between the community layout and the neighborhood relationship. The result of this study could be used in future studies or improve the quality of residential communities in Taiwan.

Keywords: community layout, neighborhood relationship, space syntax, mixed-method

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3787 Portuguese City Reconstructed from Public Space: The Example of the Requalification of Cacém Central Area

Authors: Rodrigo Coelho

Abstract:

As several authors have pointed out (such as Jordi Borja, or Oriol Bohigas), the necessity to “make center” presents itself not only as a imperative response to deal with the processes of dissolution of peripheral urbanization, as it should be assumed, from the point of view its symbolic and functional meaning, as a key concept to think and act on the enlarged city. The notion of re-centralization (successfully applied in urban periphery recompositions, such as in Barcelona or Lyon), understood from the redefinition of mobility, the strengthening of core functions, and from the creation or consolidation of urban fabrics (always articulated with policies of creation and redevelopment of public spaces), seems to become one of the key strategies over the challenge of making the city on the “city periphery”. The question we want to address in this paper concerns, essentially, the importance of public space in the (re) construction of the contemporary "shapeless city” sectors (which, in general, we associate to urban peripheries). We will seek demonstrate, from the analysis of a Portuguese case study–The Cacém Central Area requalification, integrated in Polis Program (National Program for Urban Rehabilitation and Environmental Improvement of Cities, released in 1999 by the Portuguese government), the conditions under which the public space project can act, subsequently, in the urban areas of recent formation, where, in many situations, the public space did not have a structuring role in its urbanization, seeing its presence reduced to a residual character. More specifically, we intend to demonstrate with this example the methodological and urban design aspects that led to the regeneration of a disqualified and degraded urban area, by intervening consistently and profoundly in public space (with well defined objectives and criteria, and framed in a more comprehensive strategy, attentive to the various scales of urban design).

Keywords: public space, urban design, urban regeneration, urban and regional studies

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3786 Analysis of Spatial Form and Gene of Historical and Cultural Settlements in Mountainous Areas: Illustrated by the Example of Anju Ancient Town

Authors: Sun Gang

Abstract:

A variety of functional spaces are distributed on the vast mountain waterfront. Their functional positioning presents a spontaneous form of settlement space, and the construction features show a passive impact on the natural environment. As the precious heritage of inheriting human civilization and promoting historical culture, the traditional settlement space in mountainous areas is also the local expression of landscape pattern pattern gene. Under the impact of rapid urban construction and the stimulation of the transformation of social consumption demand, the original texture, scale and ecology of the traditional mountain settlement space, especially the historical and cultural settlement space, have been affected, and the decline of characteristics hinders the development. This paper selects Anju Ancient Town, the fourth largest ancient city in China, which is located in the city of mountains and waters as the research object, and combines spatial analysis and other methods to study the characteristics and causes of its spatial morphology, analyze the internal logic in its formation and development process, build a genetic analysis map, explore the possibility of settlement inheritance and development, and provide reference for the construction, protection and inheritance of traditional mountain settlements.

Keywords: mountain traditional settlement, historical and cultural settlement space, spatial form, spatial gene

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3785 Analysis of the Physical Behavior of Library Users in Reading Rooms through GIS: A Case Study of the Central Library of Tehran University

Authors: Roya Pournaghi

Abstract:

Measuring the extent of daily use of the libraries study space is of utmost significance in order to develop, re-organize and maintain the efficiency of the study space. The current study aimed to employ GIS in analyzing the study halls space of the document center and central library of Tehran University and determine the extent of use of the study chairs and desks by the students-intended users. This combination of survey methods - descriptive design system. In order to collect the required data and a description of the method, To implement and entering data into ArcGIS software. It also analyzes the data and displays the results on the library floor map design method were used. And spatial database design and plan has been done at the Central Library of Tehran University through the amount of space used by members of the Library and Information halls plans. Results showed that Biruni's hall is allocated the highest occupancy rate to tables and chairs compared to other halls. In the Hall of Science and Technology, with an average occupancy rate of 0.39 in the tables represents the lowest users and Rashid al-Dins hall, and Science and Technology’s hall with an average occupancy rate (0.40) represents the lowest users of seats. In this study, the comparison of the space is occupied at different period as a study’s hall in the morning, evenings, afternoons, and several months was performed through GIS. This system analyzed the space relationship effectively and efficiently. The output of this study can be used by administrators and librarians to determine the exact amount of using the Equipment of study halls and librarians can use the output map to design more efficient space at the library.

Keywords: geospatial information system, spatial analysis, reading room, academic libraries, library’s user, central library of Tehran university

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3784 Inferring Cognitive Skill in Concept Space

Authors: Rania A. Aboalela, Javed I. Khan

Abstract:

This research presents a learning assessment theory of Cognitive Skill in Concept Space (CS2) to measure the assessed knowledge in terms of cognitive skill levels of the concepts. The cognitive skill levels refer to levels such as if a student has acquired the state at the level of understanding, or applying, or analyzing, etc. The theory is comprised of three constructions: Graph paradigm of a semantic/ ontological scheme, the concept states of the theory and the assessment analytics which is the process to estimate the sets of concept state at a certain skill level. Concept state means if a student has already learned, or is ready to learn, or is not ready to learn a certain skill level. The experiment is conducted to prove the validation of the theory CS2.

Keywords: cognitive skill levels, concept states, concept space, knowledge assessment theory

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3783 Fabrication of Nanoengineered Radiation Shielding Multifunctional Polymeric Sandwich Composites

Authors: Nasim Abuali Galehdari, Venkat Mani, Ajit D. Kelkar

Abstract:

Space Radiation has become one of the major factors in successful long duration space exploration. Exposure to space radiation not only can affect the health of astronauts but also can disrupt or damage materials and electronics. Hazards to materials include degradation of properties, such as, modulus, strength, or glass transition temperature. Electronics may experience single event effects, gate rupture, burnout of field effect transistors and noise. Presently aluminum is the major component in most of the space structures due to its lightweight and good structural properties. However, aluminum is ineffective at blocking space radiation. Therefore, most of the past research involved studying at polymers which contain large amounts of hydrogen. Again, these materials are not structural materials and would require large amounts of material to achieve the structural properties needed. One of the materials to alleviate this problem is polymeric composite materials, which has good structural properties and use polymers that contained large amounts of hydrogen. This paper presents steps involved in fabrication of multi-functional hybrid sandwich panels that can provide beneficial radiation shielding as well as structural strength. Multifunctional hybrid sandwich panels were manufactured using vacuum assisted resin transfer molding process and were subjected to radiation treatment. Study indicates that various nanoparticles including Boron Nano powder, Boron Carbide and Gadolinium nanoparticles can be successfully used to block the space radiation without sacrificing the structural integrity.

Keywords: multi-functional, polymer composites, radiation shielding, sandwich composites

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3782 Millimeter Wave Antenna for 5G Mobile Communications Systems

Authors: Hind Mestouri

Abstract:

The study and simulation of a millimeter wave antenna for 5G mobile communication systems is the topic of this paper. We present at the beginning the general aspects of the 5G technology. We recall the objectives of the 5G standard, its architecture, and the parameters that characterize it. The proposed antenna model is designed using the CST Microwave Studio simulation software. Numerous methods are used at all steps of the design procedures, such as theoretical calculation of parameters, declaration of parameter values, and evaluation of the antenna through the obtained results. Initially, we were interested in the design of an antenna array at the 10 GHz frequency. Afterward, we also simulated and presented an antenna array at 2.5 GHz. For each antenna designed, a parametric study was conducted to understand and highlight the role and effects of the various parameters in order to optimize them and achieve a final efficient structure. The obtained results using CST Microwave Studio showed that the characteristics of the designed antennas (bandwidth, gain, radiation pattern) satisfy the specifications of 5G mobile communications.

Keywords: 5G, antenna array, millimeter wave, 10 GHz, CST Microwave Studio

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3781 Formal Ontology of Quality Space. Location, Subordination and Determination

Authors: Claudio Calosi, Damiano Costa, Paolo Natali

Abstract:

Determination is the relation that holds between certain kinds of properties, determinables – such as “being colored”, and others, determinates – such as “being red”. Subordination is the relation that holds between genus properties – such as “being an animal”, and others, species properties – such as “being human”'. It is widely held that Determination and Subordination share important similarities, yet also crucial differences. But what grounds such similarities and differences? This question is hardly ever addressed. The present paper provides the first step towards filling this gap in the literature. It argues that a locational theory of instantiation, roughly the view that to have a property is to occupy a location in quality space, holds the key for such an answer. More precisely, it argues that both principles of Determination and Subordination are just examples of more general principles of location. Consider Determination. The principle that everything that has a determinate has a determinable boils down to the claim that everything that has a precise location in quality space is in quality space – an eminently reasonable principle. The principle that nothing can have two determinates (at the same level of determination) boils down to the principle that nothing can be “multilocated” in quality space. In effect, the following provides a “translation table” between principles of location and determination: LOCATION DETERMINATION Functionality At Most One Determination Focus At Most One Determination & Requisite Determination* Exactness Requisite Determination* Super-Exactness Requisite Determination Exactitude Requisite Determination Converse-Exactness Determinable Inehritance This grounds the similarity between Determination and Subordination. What about the differences? The paper argues that the differences boil down to the mereological structure of the regions that are occupied in quality space, in particular whether they are simple or complex. The key technical detail is that Determination and Subordination induce a “set-theoretic rooted tree” structure over the domain of properties. Interestingly, the analysis also provides a possible justification for the Aristotelian claim that being is not a genus property – an argument that the paper develops in some detail.

Keywords: determinables/determinates, genus/species, location, Aristotle on being is not a genus

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3780 Clustering Color Space, Time Interest Points for Moving Objects

Authors: Insaf Bellamine, Hamid Tairi

Abstract:

Detecting moving objects in sequences is an essential step for video analysis. This paper mainly contributes to the Color Space-Time Interest Points (CSTIP) extraction and detection. We propose a new method for detection of moving objects. Two main steps compose the proposed method. First, we suggest to apply the algorithm of the detection of Color Space-Time Interest Points (CSTIP) on both components of the Color Structure-Texture Image Decomposition which is based on a Partial Differential Equation (PDE): a color geometric structure component and a color texture component. A descriptor is associated to each of these points. In a second stage, we address the problem of grouping the points (CSTIP) into clusters. Experiments and comparison to other motion detection methods on challenging sequences show the performance of the proposed method and its utility for video analysis. Experimental results are obtained from very different types of videos, namely sport videos and animation movies.

Keywords: Color Space-Time Interest Points (CSTIP), Color Structure-Texture Image Decomposition, Motion Detection, clustering

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3779 Establishing the Legality of Terraforming under the Outer Space Treaty

Authors: Bholenath

Abstract:

Ever since Elon Musk revealed his plan to terraform Mars on national television in 2015, the debate regarding the legality of such an activity under the current Outer Space Treaty regime is gaining momentum. Terraforming means to alter or transform the atmosphere of another planet to have the characteristics of landscapes on Earth. Musk’s plan is to alter the entire environment of Mars so as to make it habitable for humans. He has long been an advocate of colonizing Mars, and in order to make humans an interplanetary species; he wants to detonate thermonuclear devices over the poles of Mars. For a common man, it seems to be a fascinating endeavor, but for space lawyers, it poses new and fascinating legal questions. Some of the questions which arise are whether the use of nuclear weapons on celestial bodies is permitted under the Outer Space Treaty? Whether such an alteration of the celestial environment would fall within the scope of the term 'harmful contamination' under Article IX of the treaty? Whether such an activity which would put an entire planet under the control of a private company can be permitted under the treaty? Whether such terraforming of Mars would amount to its appropriation? Whether such an activity would be in the 'benefit and interests of all countries'? This paper will be attempt to examine and elucidate upon these legal questions. Space is one such domain where the law should precede man. The paper follows the approach that the de lege lata is not capable of prohibiting the terraforming of Mars. Outer Space Treaty provides the freedoms of space and prescribes certain restrictions on those freedoms as well. The author shall examine the provisions such as Article I, II, IV, and IX of the Outer Space Treaty in order to establish the legality of terraforming activity. The author shall establish how such activity is peaceful use of the celestial body, is in the benefit and interests of all countries, and does neither qualify as national appropriation of the celestial body nor as its harmful contamination. The author shall divide the paper into three chapters. The first chapter would be about the general introduction of the problem, the analysis of Elon Musk’s plan to terraform Mars, and the need to study terraforming from the lens of the Outer Space Treaty. In the second chapter, the author shall attempt to establish the legality of the terraforming activity under the provisions of the Outer Space Treaty. In this vein, the author shall put forth the counter interpretations and the arguments which may be formulated against the lawfulness of terraforming. The author shall show as to why the counter interpretations establishing the unlawfulness of terraforming should not be accepted, and in doing so, the author shall provide the interpretations that should prevail and ultimately establishes the legality of terraforming activity under the treaty. In the third chapter, the author shall draw relevant conclusions and give suggestions.

Keywords: appropriation, harmful contamination, peaceful, terraforming

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3778 Energy Calculation for Excited Lithium Atom in Position Space

Authors: Khalil H. Al-Bayati, Khalid Omar Al-Baiti

Abstract:

The energy expectation value for Li-like ions systems (Li, Be+ and Be2+) hasbeen calculated and examined within the ground state (1s2sα)^2 S and the excited state (1s3sα)^2 S in position space. The partitioning technique of Hartree-Fock (H-F) has been used for existing wavefnctions.

Keywords: energy expectation value, atomic systems, ground and excited states, Hartree-Fock approximation

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3777 Thermochemical Study of the Degradation of the Panels of Wings in a Space Shuttle by Utilization of HSC Chemistry Software and Its Database

Authors: Ahmed Ait Hou

Abstract:

The wing leading edge and nose cone of the space shuttle are fabricated from a reinforced carbon/carbon material. This material attains its durability from a diffusion coating of silicon carbide (SiC) and a glass sealant. During re-entry into the atmosphere, this material is subject to an oxidizing high-temperature environment. The use of thermochemical calculations resulting at the HSC CHEMISTRY software and its database allows us to interpret the phenomena of oxidation and chloridation observed on the wing leading edge and nose cone of the space shuttle during its mission in space. First study is the monitoring of the oxidation reaction of SiC. It has been demonstrated that thermal oxidation of the SiC gives the two compounds SiO₂(s) and CO(g). In the extreme conditions of very low oxygen partial pressures and high temperatures, there is a reaction between SiC and SiO₂, leading to SiO(g) and CO(g). We had represented the phase stability diagram of Si-C-O system calculated by the use of the HSC Chemistry at 1300°C. The principal characteristic of this diagram of predominance is the line of SiC + SiO₂ coexistence. Second study is the monitoring of the chloridation reaction of SiC. The other problem encountered in addition to oxidation is the phenomenon of chloridation due to the presence of NaCl. Indeed, after many missions, the leading edge wing surfaces have exhibited small pinholes. We have used the HSC Chemistry database to analyze these various reactions. Our calculations concorde with the phenomena we announced in research work resulting in NASA LEWIS Research center.

Keywords: thermochchemicals calculations, HSC software, oxidation and chloridation, wings in space

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3776 Use the Null Space to Create Starting Point for Stochastic Programming

Authors: Ghussoun Al-Jeiroudi

Abstract:

Stochastic programming is one of the powerful technique which is used to solve real-life problems. Hence, the data of real-life problems is subject to significant uncertainty. Uncertainty is well studied and modeled by stochastic programming. Each day, problems become bigger and bigger and the need for a tool, which does deal with large scale problems, increase. Interior point method is a perfect tool to solve such problems. Interior point method is widely employed to solve the programs, which arise from stochastic programming. It is an iterative technique, so it is required a starting point. Well design starting point plays an important role in improving the convergence speed. In this paper, we propose a starting point for interior point method for multistage stochastic programming. Usually, the optimal solution of stage k+1 is used as starting point for the stage k. This point has the advantage of being close to the solution of the current program. However, it has a disadvantage; it is not in the feasible region of the current program. So, we suggest to take this point and modifying it. That is by adding to it a vector in the null space of the matrix of the unchanged constraints because the solution will change only in the null space of this matrix.

Keywords: interior point methods, stochastic programming, null space, starting points

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3775 High-Frequency Modulation of Light-Emitting Diodes for New Ultraviolet Communications

Authors: Meng-Chyi Wu, Bonn Lin, Jyun-Hao Liao, Chein-Ju Chen, Yu-Cheng Jhuang, Mau-Phon Houng, Fang-Hsing Wang, Min-Chu Liu, Cheng-Fu Yang, Cheng-Shong Hong

Abstract:

Since the use of wireless communications has become critical nowadays, the available RF spectrum has become limited. Ultraviolet (UV) communication system can alleviate the spectrum constraint making UV communication system a potential alternative to future communication demands. Also, UV links can provide faster communication rate and can be used in combination with existing RF communication links, providing new communications diversity with higher user capacity. The UV region of electromagnetic spectrum has been of interest to detector, imaging and communication technologies because the stratospheric ozone layer effectively absorbs some solar UV radiation from reaching the earth surface. The wavebands where most of UV radiation is absorbed by the ozone are commonly known as the solar blind region. By operating in UV-C band (200-280 nm) the communication system can minimize the transmission power consumption since it will have less radiation noise. UV communication uses the UV ray as the medium. Electric signal is carried on this band after being modulated and then be transmitted within the atmosphere as channel. Though the background noise of UV-C communication is very low owing to the solar-blind feature, it leads to a large propagation loss. The 370 nm UV provides a much lower propagation loss than that the UV-C does and the recent device technology for UV source on this band is more mature. The fabricated 370 nm AlGaN light-emitting diodes (LEDs) with an aperture size of 45 m exhibit a modulation bandwidth of 165 MHz at 30 mA and a high power of 7 W/cm2 at 230 A/cm2. In order to solve the problem of low power in single UV LED, a UV LED array is presented in.

Keywords: ultraviolet (UV) communication, light-emitting diodes (LEDs), modulation bandwidth, LED array, 370 nm

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3774 Design of Data Management Software System Supporting Rendezvous and Docking with Various Spaceships

Authors: Zhan Panpan, Lu Lan, Sun Yong, He Xiongwen, Yan Dong, Gu Ming

Abstract:

The function of the two spacecraft docking network, the communication and control of a docking target with various spacecrafts is realized in the space lab data management system. In order to solve the problem of the complex data communication mode between the space lab and various spaceships, and the problem of software reuse caused by non-standard protocol, a data management software system supporting rendezvous and docking with various spaceships has been designed. The software system is based on CCSDS Spcecraft Onboard Interface Service(SOIS). It consists of Software Driver Layer, Middleware Layer and Appliaction Layer. The Software Driver Layer hides the various device interfaces using the uniform device driver framework. The Middleware Layer is divided into three lays, including transfer layer, application support layer and system business layer. The communication of space lab plaform bus and the docking bus is realized in transfer layer. Application support layer provides the inter tasks communitaion and the function of unified time management for the software system. The data management software functions are realized in system business layer, which contains telemetry management service, telecontrol management service, flight status management service, rendezvous and docking management service and so on. The Appliaction Layer accomplishes the space lab data management system defined tasks using the standard interface supplied by the Middleware Layer. On the basis of layered architecture, rendezvous and docking tasks and the rendezvous and docking management service are independent in the software system. The rendezvous and docking tasks will be activated and executed according to the different spaceships. In this way, the communication management functions in the independent flight mode, the combination mode of the manned spaceship and the combination mode of the cargo spaceship are achieved separately. The software architecture designed standard appliction interface for the services in each layer. Different requirements of the space lab can be supported by the use of standard services per layer, and the scalability and flexibility of the data management software can be effectively improved. It can also dynamically expand the number and adapt to the protocol of visiting spaceships. The software system has been applied in the data management subsystem of the space lab, and has been verified in the flight of the space lab. The research results of this paper can provide the basis for the design of the data manage system in the future space station.

Keywords: space lab, rendezvous and docking, data management, software system

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3773 Defending Indigenous Working Urban Spaces Trough Visual Activism in Quito

Authors: Katherine Anson

Abstract:

This paper takes a closer look at the use of day-to-day informal working practices in Latin American spatial, cultural activism against gentrification. Through a discursive analysis of the Ecuadorian communally made film documentary San Roque: A House for All (2015), and the study of the political conflict around the gentrification of the place, the essay illustrates how the purposeful showcase of indigenous uses of space claims ownership over the city’s downtown area. This argument concludes that by making visible everyday indigenous ways of production in relation to space, the video contests the neoliberalist aim to proletarianize the urban poor, and therefore, to transform them into a landless group. This approach demonstrates that through representations of their own cultural working practices grassroots organizations consciously deconstruct/contest the capitalist urbanization of space.

Keywords: cultural activism, gentrification, indigenous working traditions, neoliberalism, urban displacement, everyday forms of resistance

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3772 Authentication Based on Hand Movement by Low Dimensional Space Representation

Authors: Reut Lanyado, David Mendlovic

Abstract:

Most biological methods for authentication require special equipment and, some of them are easy to fake. We proposed a method for authentication based on hand movement while typing a sentence with a regular camera. This technique uses the full video of the hand, which is harder to fake. In the first phase, we tracked the hand joints in each frame. Next, we represented a single frame for each individual using our Pose Agnostic Rotation and Movement (PARM) dimensional space. Then, we indicated a full video of hand movement in a fixed low dimensional space using this method: Fixed Dimension Video by Interpolation Statistics (FDVIS). Finally, we identified each individual in the FDVIS representation using unsupervised clustering and supervised methods. Accuracy exceeds 96% for 80 individuals by using supervised KNN.

Keywords: authentication, feature extraction, hand recognition, security, signal processing

Procedia PDF Downloads 87
3771 Cultural Transformation in Interior Design in Commercial Space in India

Authors: Siddhi Pedamkar, Reenu Singh

Abstract:

This report is based on how a culture transforms from one era to another era in commercial space. This transformation is observed in commercial as well as residential spaces. The spaces have specific color concepts, surface detailing furniture, and function-specific layouts. But the cultural impact is very rarely seen in commercial spaces, mostly because the interior is divine by function to a large extent. Information was collected from books and research papers. A quantitative survey was conducted to understand people's perceptions about the impact of culture on design entities and how culture dictates the different types of space and their character. The survey also highlights the impact of types of interior lighting, colour schemes, and furniture types on the interior environment. The questionnaire survey helped in framing design parameters for contemporary interior design. The design parameters are used to propose design options for new-age furniture that can be used in co-working spaces. For the new and contemporary working spaces, new age design furniture, interior elements such as visual partition, semi-visual partition, lighting, and layout can be transformed by cultural changes in the working style of people and organization.

Keywords: commercial space, culture, environment, furniture, interior

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3770 Research on Design Methods for Riverside Spaces of Deep-cut Rivers in Mountainous Cities: A Case Study of Qingshuixi River in Chongqing City

Authors: Luojie Tang

Abstract:

Riverside space is an important public space and ecological corridor in urban areas, but mountainous urban rivers are often overlooked due to their deep valleys and poor accessibility. This article takes the Qing Shui Xi River in Chongqing as an example, and through long-term field inspections, measurements, interviews, and online surveys, summarizes the problems of poor accessibility, limited space for renovation, lack of waterfront facilities, excessive artificial intervention, low average runoff, severe river water pollution, and difficulty in integrated watershed management in riverside space. Based on the current situation and drawing on relevant experiences, this article summarizes the design methods for riverside space in deep valley rivers in mountainous urban areas. Regarding spatial design techniques, the article emphasizes the importance of integrating waterfront spaces into the urban public space system and vertical linkages. Furthermore, the article suggests different design methods and improvement strategies for the already developed areas and new development areas. Specifically, the article proposes a planning and design strategy of "protection" and "empowerment" for new development areas and an updating and transformation strategy of "improvement" and "revitalization" for already developed areas. In terms of ecological restoration methods, the article suggests three focus points: increasing the runoff of urban rivers, raising the landscape water level during dry seasons, and restoring vegetation and wetlands in the riverbank buffer zone while protecting the overall pattern of the watershed. Additionally, the article presents specific design details of the Qingshuixi River to illustrate the proposed design and restoration techniques.

Keywords: deep-cut river, design method, mountainous city, Qingshuixi river in Chongqing, waterfront space design

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3769 Information Retrieval for Kafficho Language

Authors: Mareye Zeleke Mekonen

Abstract:

The Kafficho language has distinct issues in information retrieval because of its restricted resources and dearth of standardized methods. In this endeavor, with the cooperation and support of linguists and native speakers, we investigate the creation of information retrieval systems specifically designed for the Kafficho language. The Kafficho information retrieval system allows Kafficho speakers to access information easily in an efficient and effective way. Our objective is to conduct an information retrieval experiment using 220 Kafficho text files, including fifteen sample questions. Tokenization, normalization, stop word removal, stemming, and other data pre-processing chores, together with additional tasks like term weighting, were prerequisites for the vector space model to represent each page and a particular query. The three well-known measurement metrics we used for our word were Precision, Recall, and and F-measure, with values of 87%, 28%, and 35%, respectively. This demonstrates how well the Kaffiho information retrieval system performed well while utilizing the vector space paradigm.

Keywords: Kafficho, information retrieval, stemming, vector space

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3768 Exploring Non-Native English Language Teachers' Understandings and Attitudes towards the Integration of Intercultural Competence

Authors: Simin Sasani

Abstract:

This study will explore a group of English language teachers’ understanding of intercultural competence to find out if they are aware of the concept and how important it is for them. It will investigate how much they are concerned about the challenges that the learners might face in their intercultural communications and to what extent they can help the learners to overcome the barriers to increase students’ insight into cultural differences. In addition, it will explore how a group of non-native English language teachers define culture in relation to their English language teaching practices. More specifically, the research tries to take the how and why of inclusion of intercultural competence into consideration and how non-native teachers think they can improve their learners’ knowledge and skills in this domain. The study will be conducted in the UK and the participants are eight non-native English language teachers who are currently teaching general English language courses for foreigners. A pilot study have been conducted for this research which its results show three non-native English teachers are aware of the notion although they have not had any formal education about intercultural competence. Their challenges and limitation were also highlighted through interviews and observations.

Keywords: English, English language teachers, intercultural communications, intercultural competence, non-natives

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3767 Migration, Agency and Subjectivity in Helon Habila's Travellers

Authors: Bankole Wright

Abstract:

The late 20th to the early 21st century has been predominantly characterized by the movement of individuals from one country to another country or countries. The chief reasons for migration have always been premised on socio-cultural, socio-political and socio-economic factors, with influences of migration finding expression through various ways. Indeed, migration experiences have formed points of subjectivity which functions as agencies that propel migrants to strongly quest for migrating from their home space to other socio-cultural space that performs the role of escape for them. This paper interrogates the discourse of migration, agency and subjectivity in Helon Habila’s Travellers. The essay explores the interconnectedness between migration which is the physical [as deployed in this paper] movement from one location to another, agency as seen in the ability to act based on various ideological frameworks within which the action is taken, and subjectivity which identifies with the predominant factors that influence human actions; and how these connections are responsible for defining the diaspora individual. The discourse of what makes migrants desire to move from their various spaces is as critical as the experiences they face in their various host land. Hence, this paper demonstrates, through the analysis of an African diasporic novel, that the quest for migration is mostly determined by certain agencies in the diaspora home space, which characters have been subjects of and desire to escape. Traveller is a novel which chronicles the various experiences of migrants who journey from their various home space to another land as a result of different agencies that precipitated their migration. This paper engages these agencies as impediments to human survival.

Keywords: migration, agency, subjectivity, Helon Habila, diaspora, home, space

Procedia PDF Downloads 243