Architectural Point Of View Research Articles

ENERGY CONSERVATION AS A SUSTAINABLE STRATEGY FOR SMART HOME BUILDINGS IN AMMAN, JORDAN WITH IMPROVING INDOOR BUILT ENVIRONMENT FEATURES AND KEY PERFORMANCE

As an ingenious efficient environment, smart buildings can be considered as essential constituents for energy conservation. That is, in today's energy demands upsurges and energy sources degradation, the idea of the smart home building has a major implication on improving the living environment along with cutting down on energy consumptions. Therefore, this study investigates the energy conservation theme in Amman, Jordan in terms of opportunities and challenges vs. renewable energy technology. This study was based on interviews with the expert (academics, professionals architects, and electrical engineers, in addition to employees in Electrical companies) aiming to identify the problematic gap in designing theoretical analysis of a smart automated building based on collaboration work between Electrical and Architectural Engineering. From an Electrical Engineering point of view, automated control building systems can provide efficient means of comfort, sustainable habitat environment, and energy conservation as a building advantage. Such a scheme can be accomplished through automated control software (LabView), sensors, network infrastructure, logic design, and mechanical actuators. Meanwhile, from an architecture point of view, passive design strategies can reduce energy consumption along with public awareness for building users. This was implemented through simulation for base case building showing the integration between architectural and electrical systems through using a hybrid system. As a result, this new building automation design will help reducing energy consumption by controlling light fixtures, air-condition, water pumps, and many more appliances. The design guidelines, once formulated and enacted, will guarantee energy conservation qualitatively which will serve as a proposed guideline for enhancing buildings' regulation and codes.Keywords: Energy Conservation, Sustainable Strategy, Smart Building, Indoor Built Environment.JEL Classifications: Q2, Q3, Q4DOI: https://doi.org/10.32479/ijeep.11717

A Methodology for Generating Systems Architectural Glimpse Statements Using the 5W1H Maxim

Attempts to facilitate and streamline systems architecting have resulted in a great number of reusable principles, practices, mechanisms, frameworks, and tools. Such a practice is the use of architectural viewpoints and views. However, as systems change, these practices should also evolve. The increasing scale and complexity of systems resulting from an ever-growing pool of human needs and breakthroughs may lead, in some cases, to an increased gap between the abstraction activities attempting to capture the whole of a system, and the instantiation activities that produce concrete and detailed descriptions of a system’s architecture. To address this issue, this article introduces a new notion, that of architectural glimpse statements, fundamental questions acting as the building blocks for architectural views and products. This notion can help architects ask the right questions in the right manner to create fundamental statements, the elaboration on which can lead directly to concrete architectural products. Working on top of standardized and common approaches, the article introduces a language for the creation of architectural glimpse statements using the 5W1H maxim. Based on this language, a tool and guidelines are also provided to facilitate the usage of glimpses. Finally, the overall methodology is demonstrated in two case studies.

Analysis of Security Issues and Countermeasures for the Industrial Internet of Things

Industrial Internet of Things (IIoT) can be seen as an extension of the Internet of Things (IoT) services and applications to industry with the inclusion of Industry 4.0 that provides automation, reliability, and control in production and manufacturing. IIoT has tremendous potential to accelerate industry automation in many areas, including transportation, manufacturing, automobile, marketing, to name a few places. When the benefits of IIoT are visible, the development of large-scale IIoT systems faces various security challenges resulting in many large-scale cyber-attacks, including fraudulent transactions or damage to critical infrastructure. Moreover, a large number of connected devices over the Internet and resource limitations of the devices (e.g., battery, memory, and processing capability) further pose challenges to the system. The IIoT inherits the insecurities of the traditional communication and networking technologies; however, the IIoT requires further effort to customize the available security solutions with more focus on critical industrial control systems. Several proposals discuss the issue of security, privacy, and trust in IIoT systems, but comprehensive literature considering the several aspects (e.g., users, devices, applications, cascading services, or the emergence of resources) of an IIoT system is missing in the present state of the art IIoT research. In other words, the need for considering a vision for securing an IIoT system with broader security analysis and its potential countermeasures is missing in recent times. To address this issue, in this paper, we provide a comparative analysis of the available security issues present in an IIoT system. We identify a list of security issues comprising logical, technological, and architectural points of view and consider the different IIoT security requirements. We also discuss the available IIoT architectures to examine these security concerns in a systematic way. We show how the functioning of different layers of an IIoT architecture is affected by various security issues and report a list of potential countermeasures against them. This study also presents a list of future research directions towards the development of a large-scale, secure, and trustworthy IIoT system. The study helps understand the various security issues by indicating various threats and attacks present in an IIoT system.

ASTRONOMICAL OBSERVATORIES: CONSOLIDATION OF THE MODERN OBSERVATORY BETWEEN THE XVIIITH AND THE XXTH CENTURIES

In this work we present from an architectural point of view how the Modern Observatory spreads from Europe to the rest of the World, and how, throughout this process, certain characteristics are developed and consolidated that make it increasingly paving the way for development of astronomical activity.

EVALUATION OF PV POWERED SWITCHABLE GLAZING TECHNOLOGIES IN TERMS OF THEIR SUITABILITY FOR OFFICE WINDOWS IN MODERATE CLIMATES

ABSTRACT In the search for façade solutions that meet requirements for energy efficiency and office space use comfort, it seems promising to apply a combination of photovoltaic (PV) technology with switchable glazing. It is believed that the merging of these two technologies might benefit the cooperation between regulated solar protection and energy efficiency. This article provides a design outlook on the use of PV-EC, PV-SPD, and PV-LCD technologies in terms of their utility for office buildings in moderate climates. This study concerns thermal, optical-visual, energetic, and technical issues, and a comparative method was applied. Based on current scientific research, the results of the analysis were juxtaposed with the requirements of the office working environment: natural lighting, thermal protection, glare protection, privacy control, energy efficiency, and technical reliability. The juxtaposition of these aspects revealed the advantages and disadvantages of a given solution from an architectural point of view. PV-EC technology in a side-by-side system was found to be the most appropriate solution and the results may be applied to make preliminary design decisions.

إعادة تهيئة الأسطح القائمة کقيمة بيئية و اقتصادية مضافة دراسة حالة: عمارات العبور- مدينة القاهرة Retrofitting existing conventional roofs as an environmental and economic added value Case study: El Obour Buildings – Cairo City

Cairo faces many problems such as overpopulation and environmental pollution due to the lack of green spaces in it, with the lack of empty spaces suitable for cultivation. In view of the large spread of the existing residential buildings in central Cairo, a study was conducted on the feasibility of greening the existing roofs of residential buildings with one unity to retrofit the roofs of these buildings and make use of them from an environmental, economic and architectural point of view. El Obour residential buildings were chosen as an example of a populated group of buildings under the one association of the Union of Owners in order to ease the application of roof greening to them. In case of working on existing buildings, the type used in roof greening must be studied in terms of loads and the appropriate installation method for these roofs.

The Modern Value of an Ancient Tomb from an Architectural Viewpoint : Focusing on the Ancient Tombs in Bukjeong-dong, Yangsan

본 연구는 고분을 통해 고대 양산지역의 도시, 사회, 문화를 건축적 관점에서 바라본 시·공간을 사회학적 건축사상으로 논의하는데 목적이 있다. 연구방법은 고대의 건축과 도시를 유추하기 위해 5-6세기경에 존재해 왔던 북정동 고분군을 시간적 해체를 통해 건축적 사고로 의미화한 브리꼴라주의 사고 즉, ‘건축적 브리꼴라주’로 재구성하여, 문명으로 길들여진 사고방식이 아닌 통섭과 유추의 사고를 건축학에 이입해 고대 사회를 시·공간적으로 바라보고자 하였다. 북정동 고분군을 시·공간적으로 해체하고 건축적 브리꼴라주로 재구성한 논의로 결론에 이르는 방향은 다음과 같다. 첫째, 북정동 고분군과 같은 권역에 있고 고분과 극적인 조화를 이끌 수 있으며 삼국시대부터 조선시대까지 역사·전통적 가치가 있는 신기동 산성은 속히 복원해 고분과 대조되는 상관적 시간의 인식을 시작으로 도시공간의 여러 시간적 가치를 부여해야 할 것이다. 둘째, 부부총의 코오벨식 구조와 고대 건축의 공포양식이 켄틸레버 구조로 공통점이 있다는 유추는 동일한 구조 원리가 공존했으므로 전통건축에도 추측 가능한 사회·문화적 표현 가치를 찾을 수 있어야 할 것이다. 셋째, 성황산부터 양산천에 이르는 영역은 고대의 산성과 고분이 도시의 원경관(原景觀)을 형성하는 원점이 되므로 도시공간문화에 긍정적으로 작용할 삼국·고려·조선·근대·현대의 시간적 흐름을 이루는 요인들을 찾아서 복원·개발해야 할 것이다.

RECORDING AND COMPARING HISTORIC GARDEN ARCHITECTURE. VALUE OF SLAM-BASED RECORDING FOR RESEARCH ON CULTURAL LANDSCAPES IN CONNECTION WITH HERITAGE CONSERVATION

Abstract. The 3D-SLAM-based recording of historic gardens and architecture with the scope of geometric and quantitative analysis of typologies of garden architecture in the context of a designated cultural landscape will be presented. This will be illustrated by case studies of three baroque gardens of buildings belonging to the Cistercian order.The ‘Centre for Heritage Conservation studies and Technologies’ (KDWT) at the University of Bamberg is cooperating with the Cisterscapes project to deliver metric surveys, architectural comparison of the historic gardens as typical feature of the agricultural granges. The survey and research were conducted in autumn 2020 and 2021 in two granges in Franconia (Bavaria, Germany) as well as on the monastery of Ebrach.For the recording, SLAM technology, was the preference and a GeoSLAM ZEB Horizon was used. It is a solution using the data sequence acquired during motion for estimating the relative poses in real time. The case studies served not only to generate an accurate output to be explored in the Cistercian Cultural Heritage Project, but also as test of the instrumentation to ascertain best practices of the instrument. 3D digital documentation will contribute to the holistic understanding of garden plus architecture ensembles. 3D data analysis will be approached from an art-historical and architectural viewpoint, conclusions shall be drawn from interdisciplinary cooperation. This comparative research will serve to find similarities or differences and establish prototypical elements of these typical elements of Cistercian Cultural Landscape. The 3D records can also be used as basis for future monitoring and development of a new garden care concept taking heritage conservation into account. Heritage, in its many forms, is not only a representation of the past, but a connection or reconnection with a past that is active and alive in the present. It shapes and reshapes people’s sense of place, sense of belonging and cultural identities at the local and national level.

Web Application for Statistical Tracking and Predicting the Evolution of Active Cases with the Novel Coronavirus (SARS-CoV-2)

Since February 2020, when the first case of infection with SARS COV-2 virus appeared in Romania, the evolution of COVID-19 pandemic continues to have an ascending allure, reaching in September 2020 a second wave of infections as expected. In order to understand the evolution and spread of this disease over time and space, more and more research is focused on obtaining mathematical models that are able to predict the evolution of active cases based on different scenarios and taking into account the numerous inputs that influence the spread of this infection. This paper presents a web responsive application that allows the end user to analyze the evolution of the pandemic in Romania, graphically, and that incorporates, unlike other COVID-19 statistical applications, a prediction of active cases evolution. The prediction is based on a neural network mathematical model, described from the architectural point of view.

Hardware Implementation of Differential Oscillatory Neural Networks Using VO 2-Based Oscillators and Memristor-Bridge Circuits.

Oscillatory Neural Networks (ONNs) are currently arousing interest in the research community for their potential to implement very fast, ultra-low-power computing tasks by exploiting specific emerging technologies. From the architectural point of view, ONNs are based on the synchronization of oscillatory neurons in cognitive processing, as occurs in the human brain. As emerging technologies, VO2 and memristive devices show promising potential for the efficient implementation of ONNs. Abundant literature is now becoming available pertaining to the study and building of ONNs based on VO2 devices and resistive coupling, such as memristors. One drawback of direct resistive coupling is that physical resistances cannot be negative, but from the architectural and computational perspective this would be a powerful advantage when interconnecting weights in ONNs. Here we solve the problem by proposing a hardware implementation technique based on differential oscillatory neurons for ONNs (DONNs) with VO2-based oscillators and memristor-bridge circuits. Each differential oscillatory neuron is made of a pair of VO2 oscillators operating in anti-phase. This way, the neurons provide a pair of differential output signals in opposite phase. The memristor-bridge circuit is used as an adjustable coupling function that is compatible with differential structures and capable of providing both positive and negative weights. By combining differential oscillatory neurons and memristor-bridge circuits, we propose the hardware implementation of a fully connected differential ONN (DONN) and use it as an associative memory. The standard Hebbian rule is used for training, and the weights are then mapped to the memristor-bridge circuit through a proposed mapping rule. The paper also introduces some functional and hardware specifications to evaluate the design. Evaluation is performed by circuit-level electrical simulations and shows that the retrieval accuracy of the proposed design is comparable to that of classic Hopfield Neural Networks.

Implementation of an Adaptive Case Management System Supporting the Incident Management Process in ABAP-Based SAP Systems

Adaptive Case Management (ACM) can be a viable option for supporting knowledge-intensive processes like the incident management process (IM) in IT service management. To this end, a concept for an Adaptive Case Management system (ACMS) able to support the incident management process according to ITIL was described by Meyer, Wittmann, et al. (2021). To prove the concept’s feasibility, a prototype based on SAP HANA and the SAP Solution Manager, which uses ticket text similarity determination to recommend existing tickets to incident processors and tracks incident processor activities in SAP ABAP-based systems through SAP UI Logging is implemented in the following. The prototype is then shown to five industry-pundits in scope of a case study to evaluate the built artifact. Furthermore, an evaluatory analysis from a descriptive and an architectural point of view is done. The evaluations’ results show, that while not constituting a complete, high-fidelity solution, the prototype displays great promise in increasing efficiency and effectiveness in the IM process.

Design of an Educational Virtual Assistant Software

Despite the great creators’ efforts of e-learning educational materials, it is not possible to define the content of these materials specifically for all students. Based on this, it is necessary to provide in e-learning education the possibility of a more detailed interpretation of specific parts of the educational material that may be unclear to specific students. Based on this fact, we decided to take the first step in the form of software design, which will represent a virtual assistant in teaching computer science. The role of this assistant will be the ability to answer technical questions related to the presented curriculum. From an architectural point of view, it will be a set of micro-services, each of which will serve a specific task. The prerequisite is the use of decision trees to determine a specific micro-service, which will be implemented in the form of a neural network. Main aim of this paper is to provide detail description of global software architecture for such a virtual assistant

ENHANCING THE INVESTMENT ATTRACTIVENESS AND EFFECTIVENESS OF THE SPECIAL ECONOMIC ZONE

<p>Currently, the development of the country's economy is characterized by the trend of globalization, which is constantly developing, modernizing, acquiring new forms and features, which ultimately radically changed the way of the world economy. The task was set to analyze and propose options for improving the investment attractiveness and efficiency of the functioning of the special economic zone of the industrial and production type "Center" in the Voronezh Region. The analysis of the existing territory was carried out, as a result of which the weaknesses and opportunities for modernization and development of the zone as a whole were identified.</p><p>The article presents proposals for increasing and reorganizing the territory, develops a development plan, and suggests ways to attract customers and investments from an architectural and construction point of view. The levels of interaction between humans and the architectural and landscape environment are studied, and the key points of development are identified. The results obtained make it possible to apply and evaluate according to these criteria with the specified characteristics, using the design code development methodology to increase the efficiency of the territory's functioning.</p>

Digital Ecosystems for Developing Digital Twins of the Earth: The Destination Earth Case

This manuscript discusses the key characteristics of the Digital Ecosystems (DEs) model, which, we argue, is particularly appropriate for connecting and orchestrating the many heterogeneous and autonomous online systems, infrastructures, and platforms that constitute the bedrock of a digitally transformed society. Big Data and AI systems have enabled the implementation of the Digital Twin paradigm (introduced first in the manufacturing sector) in all the sectors of society. DEs promise to be a flexible and operative framework that allow the development of local, national, and international Digital Twins. In particular, the “Digital Twins of the Earth” may generate the actionable intelligence that is necessary to address global change challenges, facilitate the European Green transition, and contribute to realizing the UN Sustainable Development Goals (SDG) agenda. The case of the Destination Earth initiative and system is discussed in the manuscript as an example to address the broader DE concepts. In respect to the more traditional data and information infrastructural philosophy, DE solutions present important advantages as to flexibility and viability. However, designing and implementing an effective collaborative DE is far more difficult than a traditional digital system. DEs require the definition and the governance of a metasystemic level, which is not necessary for a traditional information system. The manuscript discusses the principles, patterns, and architectural viewpoints characterizing a thriving DE supporting the generation and operation of “Digital Twins of the Earth”. The conclusions present a set of conditions, best practices, and base capabilities for building a knowledge framework, which makes use of the Digital Twin paradigm and the DE approach to support decision makers with the SDG agenda implementation.

Mutation of the Seaside Architecture in Algeria and its Impact on Coastal Landspace. A Case Study: Ain El Turc, Algeria

The sea strongly contributes to the identity of coastline areas. Moreover, it has been demonstrated that the coastline is a geographical entity which calls for specific organization. From an architectural point of view, design elements have been associated with the assets (or constraints) of the site. Thus, the view is associated with the bow window, protection against the climate with canopies and protruding roofs, and quality of the soil and bedrock. Integration into the site is also highly desirable, both in form (ship) and in construction materials. The urbanization of coastal areas in Algeria is a colonial fact. In pre-colonial times, little importance was given to these areas, whereas later they became a priority: port sites, the speed of communications with Europe, rich agricultural plains, a mild climate and welcoming beaches. The developments and seaside constructions carried out during this period were part of the logic of attractiveness to welcome more European settlers and promote the sedentarization and growth of those already living in Algeria. After independence, political and economic choices did not unfortunately take into account the geographical and climatic specificity of Algeria’s coastal zones. Thus, population growth and rural depopulation have led to a sharp increase in the demand for real estate, which has resulted in unbridled urbanization, regardless of the seaside vocation of these territories. In this article, based on the case of the seaside resort of Ain El Turc, which has colonial architectural production of an exceptional quality that takes into account the specificities of the coastline and the presence of the sea, the aim is to assess and verify if this architecture was perpetuated after independence. To this end, we have highlighted, through bibliographic research, the characteristics of seaside architecture from the 19th and 20th centuries and those of the contemporary time. An analysis of all the dwellings located in the Saint Rock district in the municipality of Ain El Turc consisted in identifying these characteristics and establishing a classification of these constructions.

Techniques to Improve B2B Data Governance Using FAIR Principles

Sharing data along the economic supply/demand chain represents a catalyst to improve the performance of a digitized business sector. In this context, designing automatic mechanisms for structured data exchange, that should also ensure the proper development of B2B processes in a regulated environment, becomes a necessity. Even though the data format used for sharing can be modeled using the open methodology, we propose the use of FAIR principles to additionally offer business entities a way to define commonly agreed upon supply, access and ownership procedures. As an approach to manage the FAIR modelled metadata, we propose a series of methodologies to follow. They were integrated in a data marketplace platform, which we developed to ensure they are properly applied. For its design, we modelled a decentralized architecture based on our own blockchain mechanisms. In our proposal, each business entity can host and structure its metadata in catalog, dataset and distribution assets. In order to offer businesses full control over the data supplied through our system, we designed and implemented a sharing mechanism based on access policies defined by the business entity directly in our data marketplace platform. In the proposed approach, metadata-based assets sharing can be done between two or multiple businesses, which will be able to manually access the data in the management interface and programmatically through an authorized data point. Business specific transactions proposed to modify the semantic model are validated using our own blockchain based technologies. As a result, security and integrity of the FAIR data in the collaboration process is ensured. From an architectural point of view, the lack of a central authority to manage the vehiculated data ensures businesses have full control of the terms and conditions under which their data is used.

Typology of courtyards in apartment block development based on planning openness and permeability

In the Russian Federation, the problem of creating a comfortable urban environment is of a national nature. The authors suggest paying attention to the courtyard in apartment block development as this area is one of the most important elements of the urban environment – a buffer space between the apartment and the city. As an important criterion for a comfortable environment is its safety, therefore, it is necessary to understand which courtyards form a sense of security in people, and which do not. The formation of a sense of security of residents is influenced by many different factors. Courtyards, having a different planning arrangement, create different conditions for the comfort of living inhabitants and the degree of use by other people. The authors propose the development of a typology of courtyard spaces based on a sense of comfort and security. As basic characteristics they propose to use: planning openness of the yard, which characterizes the degree of built perimeter of the yard, as well as the permeability of the territory, indicating the accessibility of this area for other residents and their activity. This typology will be the basis for further determining how each type affects the formation of a sense of security among residents and what measures from an architectural point of view can be applied to ensure the formation of this feeling.

Tectonics of Sukuh Temple as construction structure environmental response (earthquake friendly)

The large number of temples and various forms in Indonesia is a cultural and architectural heritage that is one of the identities of the archipelago. From an architectural point of view, the temple has special tectonic complexities, one of which is the Sukuh Temple. Sukuh Temple is a building with the ability of a perfect structural and construction system and has architectural metaphysical values. The building of Sukuh Temple has existed since the 15th century. This building was built to fulfill the function of worship rituals, therefore this building is sacred. This building is located in an earthquake prone area, namely on the island of Java. The resilience of Sukuh Temple over the years proves that Sukuh Temple can adapt to the environment, from this evidence the tectonics of Sukuh Temple are interesting to study. The research objective was to determine how the ancestors used tectonic science and technology to adapt to nature and the existing environment. This research uses descriptive method with a qualitative approach. data and information collection is done through field observations, in-depth interviews, and related documents. This study found that local wisdom is the main factor that makes Sukuh Temple responsive to the environment.

Geometrical Analysis of Oval Domes through Architectural and Mathematical Methods. The Case of the Dome of the Camarín of the Virgin of El Puig (Valencia, Spain)

ABSTRACT The study of oval geometry domes encompasses a broad and interesting field of research that can be approached from multiple points of view. This paper shows the multidisciplinary approach developed for the analysis of the geometry of this type of domes from the architectural and mathematical points of view. This research paper focuses on the geometric study of the dome of the Camarín of the Virgin, of the Monastery of El Puig de Santa Maria (Valencia, Spain), an emblematic building of Valencian history and architecture. It begins with a survey by means of a multi-image photogrammetry and other surveying methods obtaining a point cloud that has served as a base for the geometric analysis. The approach to this analysis is through graphic and mathematical gradients, which allows to determine the graphic layouts and equations that best define the shape of the dome as well as drawing up a geometric construction hypothesis, which is consistent with the data. The conclusion obtained is that the dome is generated by an elliptical plan and five-centered oval arches in the vertical sections and the methodological process developed can applied to other cases.

Tri-optimization of building shape and envelope properties using Taguchi and constraint limit method

PurposeThe purpose of this paper is to present a tri-optimization approach to optimize design solutions regarding the building shape and envelope properties considering their implications on thermal comfort, visual comfort and building energy consumption (EN). The optimization approach has been applied to obtain the optimal design solutions in five typical cities across all climatic regions of China.Design/methodology/approachThe method comprises a tri-optimization process with nine main steps to optimize the three objectives (thermal comfort, visual comfort and building EN). The design variables considered are four types of building shape (pyramid, rectangular, cylindrical and dome shape) and different envelope properties (insulation thickness [INS] of external walls/roof, window type [WT] and window-to-envelop surface area ratio [WESR]). The optimization is performed by using the Taguchi and constraint limit method.FindingsThe results show that the optimal design solutions for all climatic regions favor cylindrical shape and triple-layer low-E glazing window. The highest insulation level of 150 mm is preferred in three climatic regions, and the INS of 90 mm is preferred in the other two climate regions. In total, 10% WESR is preferred in all climatic regions, except the mild region. When the constraint limit of lighting intensity requirement by Leadership in Energy and Environmental Design (LEED) is applied, the rectangular shape building is the optimal solution for those with 10% WESR.Research limitations/implicationsThe method proposed in the paper is innovative in that it optimizes three different objectives simultaneously in building design with better accuracy and calculation speed.Practical implicationsBuilding designers can easily follow the proposed design guide in their practice which effectively bridges the gap between theory and practice. The optimal design solutions can provide a more comfortable living environment and yet less EN, which can help achieve the sustainability requirement of green buildings.Social implicationsThe solutions presented in the paper can serve as a useful guide for practical building designers which creates economic and commercial impact. In addition, the theory and practical examples of the study can be used by building regulators to improve the energy-efficient building design standard in China.Originality/valueThe research is the first attempt that adopts tri-optimization approach to generate the optimal solutions for building shape and envelope design. The tri-optimization approach can be used by building designers to generate satisfactory design solutions from the architectural viewpoint and meanwhile to find combinations of the building shape and envelope properties that lead to design solutions with optimal building performance.