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Discovering Network Neighborhoods Using Peer-to-Peer LookupsLehman, Li-wei, Lerman, Steven 01 1900 (has links)
In many distributed applications, end hosts need to know the network locations of other nearby participating hosts in order to enhance overall performance. Potential applications that can benefit from the location information include automatic selection of nearby Web servers, proximity routing in a peer-to-peer system, and loss recovery in reliable multicasting. We focus in this paper on the network neighborhood discovery problem in large-scale distributed systems. In these systems, the number of participating nodes can be very large, and the membership can dynamically change. Our goal is for each node to discover other "nearby" participating nodes in a completely decentralized manner, where each node probes only a small subset of other nodes in the system. This approach will lead to improved overall performance by matching client requests for services with participants in the peer-to-peer service system that are, on average, nearby in the network sense. Recent works in distributed peer-to-peer systems, such as Chord, CAN, Tapestry and Pastry, provide efficient distributed lookup structures. In this paper, we investigate a rendezvous-based scheme for a node to discover other nearby participating nodes using a peer-to-peer lookup system such as Chord. Given a key, the Chord protocol maps the key onto a node. Our idea for network neighborhood discovery is for each host to compute a key that characterizes its network location on the Internet. We call such a key the location key, and the nodes that these location keys are mapped to the Rendezvous Points. To lookup other nearby participating nodes, a node seeking some service queries its corresponding rendezvous point using its location key. We focus on the issue of how to generate the location key in a distributed fashion such that nodes that are close to each other in the actual network will have similar location key values, and therefore be mapped to nearby locations on the Chord ring. In this paper, we examine the performance tradeoffs of such a rendezvous scheme using the Global Network Positioning (GNP) approach to generate the location keys. In GNP, each node measures its network distances to a few landmark nodes to derive its coordinates in a D-dimensional geometric space. We generate a host's Chord location key from its 1-dimensional GNP coordinate, and use coordinates from a higher dimensional space to refine the searching process for the closest node. We evaluate our scheme in the context of the nearest neighbor discovery problem. Using data from the Active Measurement Project of the National Laboratory for Applied Network Research (NLANR), we compare its performance with a random mapping scheme, where location keys are randomly generated. Using our coordinate-based rendezvous scheme, 66% of the nodes found their actual closest network neighbor by pinging only a small number of nodes. / Singapore-MIT Alliance (SMA)
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Lokalizace stanic v síti Internet pomocí umělých souřadnicových systémů / Node localization on the Internet using artificial coordinate systemsŠkvor, Martin January 2010 (has links)
This thesis is focused on methods for nodes localization in Internet using latency prediction in synthetic coordinates systems. Thesis also deal with methods, which latency prediction between nodes is based on other systems. Among such a methods particularly belongs King, which uses DNS (domain name service). Furthermore, thesis deal with relevance of overlay networks in latency prediction and their use for different services. Practical part of this thesis concentrates on method for latency prediction in synthetic coordinate system Global Network positioning. There were made two programs for counting coordinates of landmarks and hosts in this system. Measurements and calculations made in this thesis, are focused to determine accuracy of latency prediction of this method and their evaluation is made at the end of thesis.
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企業集團全球網絡與在地治理模式研究以華碩集團為例 / Corporate group global network and localized business management model: Case study Asus.王樂平 Unknown Date (has links)
過去對於台灣單一廠商朝向大型集中化的企業集團發展及其在地交易治理模式的現象較少涉及,本研究由網絡理論出發,扣連華碩集團作為研究場域,援引Håkanson企業全球擴張模式,企圖論證華碩企業集團化過程中,如何透過獨資或合資之進入模式,佈局全球在地網絡關係,進而運用Powell組織治理模式,探討企業集團在地網絡治理模式。有別於過去文獻單從政治經濟學詮釋企業集團介入不同產業時,強調國家角色的重要性;或者從經濟地理學探討單一產業之廠商全球佈局或跨界生產網絡建構與在地鑲嵌實證研究,期能補充過去文獻之不足。經研究後發現:
一、Håkanson於1979年所提出之企業集團全球擴張模式,無法適用於華碩全球網絡擴張模式。
經本研究分析,Håkanson所提出的企業集團全球擴張模式,無法適用於華碩企業集團的全球網絡擴張模式,就其原因,應與現今之企業集團受全球網絡接軌、資訊技術的進步、市場全球化、專業技術的研發及台灣中小企業的靈活性等因素影響。故本研究依華碩案例,整理出企業集團全球擴張模式的三階段,1.單一廠商及採用海外銷售代理商階段;2.滲透到個國內外市場階段;3.產生跨國產業的公司。
二、Powell的組織交易治理模式,可以解釋華碩企業集團全球網絡下各公司在地網絡治理行為。
Powell強調網絡是一個重要的組織交易治理模式,相關研究亦指出華人企業比較重視「網絡」,透過華碩企業集團案例分析,顯示研發活動受到確保關鍵技術的限制而採用層級型;在製造活動上,受到控制產品品質及降低成本的需求,初期會採用層級型,然後隨着產品多樣化而採用網絡層級型;行銷活動為了獲取最大的銷售利益,在單一技術多角化經營期間採用市場網絡型,隨着產品多樣化而採用市場型。
三、本研究所選擇的四個影響在地組織交易治理模式因素,僅有企業價值活動具解釋性。
透過企業發展階段、各公司設立時間、進入模式及企業價值活動等四個選擇因素的迴歸分析,發現各分、子公司所從事的企業價值活動對在地組織交易治理模式有顯著影響。 / There are few researches on how a Taiwanese single manufacturer developing into a hyper-centralized group and what its localized business and management model is. Hence this paper is employed the network theory to Asus as studied case and applied Håkanson’s Corporate Global Expansion Model for Asus’ group developing process to try to explain how employ solely or joint investment entering model to layout global localized network. Furthermore, employ Powell’s organization management model to explore corporate group’s local management network. This dissertation is different from most papers focus on the role of country when interpreting from political economy view that how corporate group enters various industry. It is also different from economic geography view to explore how one single manufacturer layout globally or across industry to setup and localize completely production. I hope the approach of this paper can fill the gap.
Findings:
1. Håkanson’s Corporate Global Expansion Model submitted in 1979 can not be applied for Asus’ global network expansion model.
The reason why Håkanson’s Corporate Global Expansion Model can not be applied for Asus’ global network expansion model is modern corporate group is highly influenced by global network, information technology, market globalized, and the development of professional skills, and the flexibility for Taiwanese middle and small companies. It can be concluded that there are three stages for the corporate group to expand globally based on case Asus. First is one single producer and oversea sales agent, the next step is penetrating to foreign market, and the third phase is one cross-country manufacturer is born.
2. Powell’s organization management model can explain how Asus’ individual company’s local managing behavior under the global umbrella of Asus Corporate Group.
Powell emphasizes the network is a very important organization business management model. All the relative researches also point out that Chinese enterprises consider “network” more important than the others. Base on the stud of Asus, this paper indicates R & D development is restricted for protecting critical technology so as to employ ranking mode. As in production, by the request of controlling product quality and lowering down cost, at first, the ranking mode is required, then, along with product variety increasing, the network mode is employed. Marketing activity aims to maximize selling profit. Asus employs market network mode for a single technology with diversified managing phase while market mode for product variety situation.
3. Researching four chosen factors of influencing local organization business managing model, enterprise value activity only is explainable.
Based on the regression analysis for four chosen factors as enterprise developing stages, the setup date of each subsidiary or branch office, entering models, and enterprise value activity, the enterprise value activity of each subsidiary or branch office does significant influence on local organization business managing model.
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Stadsplanering för en åldrande befolkning : En fallstudie av Ulleråkersprojektet i Uppsala / Planning for an ageing population : A case study of Ulleråker, UppsalaElfström, Elin January 2017 (has links)
Äldreperspektivet i stadsplaneringen är ett nästintill outforskat område i Sverige. Samtidigt står vi i Sverige, precis som i många andra länder, inför stora demografiska utmaningar kopplade till den snabbt åldrande befolkningen. Där stadsplanering med ett äldreperspektiv identifierats som en i raden av insatser som krävs för att möta de utmaningar som en åldrande befolkning för med sig. I den här studien har äldrevänlig stadsplanering undersökts utifrån en fallstudie av stadsutvecklingsprojektet Ulleråker i Uppsala kommun. En kommun som sommaren 2016 gick med i Världshälsoorganisationens (WHO:s) globala nätverk för åldersvänliga städer och samhällen, och därmed precis påbörjat sin resa mot att bli en mer äldrevänlig stad. Då äldreperspektivet är ett nytt fenomen i svensk stadsplanering, saknas kunskapen om vad kommunen bör göra för att tillgodose ett sådant perspektiv, vilket utgjort utgångspunkten för denna studie. Studiens syfte har på så sätt varit att bidra med ökade kunskaper om innebörden av äldrevänlig planering, och hur Uppsala kommun skulle kunna utveckla sitt arbete för att på ett bättre sätt tillgodose ett äldreperspektiv. Materialet som legat till grund för fallstudien baseras på dokumentstudier av styrdokument och planhandlingar, samt intervjuer med aktörer som är involverade i stadsplaneringen utifrån ett äldreperspektiv i Uppsala. I studien identifieras en rad faktorer som inom forskningsvärlden framhävts som betydelsefulla vid planeringen av en äldrevänlig stad. Och resultatet från fallstudien tyder på att kommunen, trots att de inte uttalat arbetar med ett äldreperspektiv i stadsplaneringen idag, indirekt tillgodoser vissa delar av äldreperspektivet i sin planering. Samtidigt identifieras i studien en rad förbättringsområden. Bland annat att synen på äldreperspektivet bör tydliggöras och breddas, samt att kommunen bör anta en gemensam målsättning för äldreperspektivet. Likaså föreslås att hanteringen av äldreperspektivet bör ses över, för att förtydliga vilka delar av den kommunala organisationen som ska vara ansvarig för att uppfylla vilka delar av äldreperspektivet. Fallstudien pekar även på att frågan om äldres boende bör lyftas tidigare i planeringsprocessen än vad som görs idag. Slutresultatet från studien, indikerar att ökad kunskap om äldreperspektivet bidrar till att öka medvetenheten om vilka vi planerar för och hur äldre påverkas av olika beslut gällande stadsmiljön, vilket kan ses som en förutsättning för ett medvetet och hållbart samhällsbyggande. / The elderly perspective is currently missing in urban planning in Sweden. At the same time, Sweden and many other countries are facing demographic challenges in terms of an ageing population. However, the integration of an elderly perspective into the planning process of cities can be considered as one of a number of efforts to meet these challenges. In this study, an elderly-friendly planning approach has been investigated through a case study of the urban development project Ulleråker in Uppsala, Sweden. In 2016, Uppsala municipality became a member of the WHO global network for age-friendly cities and communities. Hence, the municipality of Uppsala has just begun its journey towards becoming an elderly-friendly city. Since the elderly perspective is a comparatively new phenomenon in the planning agenda in Sweden, the municipality lacks the knowledge needed to cater for such a perspective. With this as a starting point, the purpose of this study is to advance knowledge of elderly-friendly planning, as well as identify ways in which Uppsala municipality could improve their planning procedures to better meet the needs of the elderly in the urban environment. The case study is based on document reviews of regulatory and planning documents linked to the development project of Ulleråker. In addition, five in-depth interviews have been carried out with actors involved in the planning process from an elderly perspective in Uppsala. The study identifies a number of factors of importance in creating an elderly-friendly urban environment. On the one hand, the result of the case study indicates that the municipality does not explicitly consider an elderly perspective in the municipal planning process. On the other hand, the same case study reveals that an elderly perspective is considered indirectly to some extent. Furthermore, the study highlights a number of areas of improvement in order to strengthen the elderly perspective in Uppsala. For instance, it is suggested that the municipality should broaden its view of the needs of older people in urban environments. In addition, the municipality’s handling of the issue should be reviewed to determine the extent to which different parts of the municipal organisation should be responsible for ensuring different factors in creating an elderly-friendly urban environment. Moreover, the case study also suggests that the dwelling issue of elderly people should be considered at an earlier stage in the planning process compared to what is done today. The conclusion indicates that increased knowledge about the elderly perspective in urban planning may raise the awareness of who we plan for, and how older people are affected by different decisions concerning the urban environment. Which can be understood as a precondition for sustainable development.
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Разработка стратегии развития экспорта товаров для регионов России в современной мировой экономике (на примере Свердловской области) : магистерская диссертация / Working out of a strategy for the development of exports of goods for the regions of Russia in the modern world economy (on the example of the Sverdlovsk region)Ананьина, А. А., Ananina, A. A. January 2017 (has links)
The paper reviewed the existing methodological approaches to the assessment of the export business of industrial regions of Russia. On their basis, we proposed the author's methodology for researching the working-out and development of the region's commodity export strategy, which consists in a comparative analysis of the potential of the industrial regions of Russia in the system of indicators, on exports of different countries and the Sverdlovsk region, on the commodity structure of regional exports; in the context analysis of the concepts and strategies of foreign economic activity of the regions; in determining the orientation of foreign economic relations of the Sverdlovsk region; in determining the level of internationalization of the largest exporters of Sverdlovsk region and their integration into the World Economic System; in the calculation of deferred dividends. The result of this methodology is the development of analysis findings and direction to increase the attractiveness of territories and increase exports, the national share in the global value chains, incl. mechanisms, methods, ways, etc. Next, we conducted an approbation of the proposed author's methodology, based on it, developed a new strategy for the development of exports of goods in the Sverdlovsk region and showed that the existing export development strategy for Sverdlovsk region's products implies an increase in exports in the standard way, that is, through the search for new markets, increase production of intermediate goods, the creation of a single commodity by different enterprises and the maintenance of relations with already existing trading and strategic partners. The new model of the strategy is based on combining of the maximum efforts of enterprises to create a large finished product and the output with this product in a new economic space, as well as an increase in the output of goods with high added value. In addition, it is proposed to conclude not only a classical contract of sale, but also a profit sharing agreement. In other words, our strategy is based on the geo-economic approach, which implies the creation of long internationalized investment-reproduction cycles.
The new approach should not just increase exports, create new finished goods, but also increase the competitiveness and investment attractiveness of the region. / В работе были рассмотрены существующие методические подходы к оценке экспортной деятельности индустриальных регионов России. На их основании мы предложили авторскую методику исследования развития и разработки стратегии товарного экспорта регионов, которая заключается в сравнительном анализе потенциала индустриальных регионов России по системе показателей, по экспорту разных стран и СО, по товарной структуре экспорта регионов; в контен-анализе концепций и стратегий внешнеэкономической деятельности регионов; в определении ориентированности внешнеэкономических связей Свердловской области; в определении уровня интернационализации курпнейших экспортеров СО и их интеграции в МЭС; в расчете отложенных дивидендов. Итогом такой методики является разработка выводов анализа и направления для повышения привлекательности территорий и увеличение объемов экспорта, национальной доли в ГЦДС, в т.ч. механизмы, методы, способы и т.д. Далее мы провели апробацию предложенной авторской методики, на ее основании разработали новую стратегию развития экспорта товаров Свердловской области и показали , что существующая стратегия развития экспорта товаров Свердловской области подразумевает увеличение объемов экспорта стандартным путем, то есть через поиск новых рынков сбыта, увеличение производства промежуточных товаров, создание единичного товара разными предприятиями и поддержание отношений с уже существующими торговыми и стратегическими партнерами. Новая же модель стратегии основана на объединении максимальных усилий предприятий для создания крупного готового продукта и выход с этим продуктом в новое экономическое пространство, а также увеличение выпуска товара с высокой добавленной стоимостью. Кроме того, предлагается заключать не только классический договор купли-продажи, но и договор участия в прибылях. Другими словами наша стратегия основана на геоэкономическом подходе, который подразумевает создание длинных интернационализированных инвестиционно-воспроизводственных циклов.
Новый подход должен не просто увеличить объемы экспорта, создать новыt готовые товары, но также повысить конкурентоспособность и инвестиционную привлекательность региона.
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Optimalizace predikce pozice v síti / Optimization of network position predictionPospíšil, Petr January 2008 (has links)
This work is about position prediction in network, it is focused to find Landmark closest to the Host in the network (with lowest distance vector). The algorithm is based on GNP system. In terms of GNP system simulation was selected method for mathematical part of position prediction. The method was Simplex Downhill. The designed algorithm was implemented in Java. In the first step chose Host continent by meassuring the distance vector. In next step is selected nearest part in the continent. In conclusion estimate Host its position and then closest Landmark. Results from this work is important for designing TTP protocol. The verdict is that the GNP can be used for TTP, but Landmarks must be located in uniform density.
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