139,393 research outputs found
Low diameter graph decompositions by approximate distance computation
No full textIn many models for large-scale computation, decomposition of the problem is key to efficient algorithms. For distance-related graph problems, it is often crucial that such a decomposition results in clusters of small diameter, while the probability that an edge is cut by the decomposition scales linearly with the length of the edge. There is a large body of literature on low diameter graph decomposition with small edge cutting probabilities, with all existing techniques heavily building on single source shortest paths (SSSP) computations. Unfortunately, in many theoretical models for large-scale computations, the SSSP task constitutes a complexity bottleneck. Therefore, it is desirable to replace exact SSSP computations with approximate ones. However this imposes a fundamental challenge since the existing constructions of low diameter graph decomposition with small edge cutting probabilities inherently rely on the subtractive form of the triangle inequality, which fails to hold under distance approximation. The current paper overcomes this obstacle by developing a technique termed blurry ball growing. By combining this technique with a clever algorithmic idea of Miller et al. (SPAA 2013), we obtain a construction of low diameter decompositions with small edge cutting probabilities which replaces exact SSSP computations by (a small number of) approximate ones. The utility of our approach is showcased by deriving efficient algorithms that work in the CONGEST, PRAM, and semi-streaming models of computation. As an application, we obtain metric tree embedding algorithms in the vein of Bartal (FOCS 1996) whose computational complexities in these models are optimal up to polylogarithmic factors. Our embeddings have the additional useful property that the tree can be mapped back to the original graph such that each edge is “used” only logaritmically many times, which is of interest for capacitated problems and simulating CONGEST algorithms on the tree into which the graph is embedded
Konaklama İşletmelerinde Deneyimsel Pazarlama ve Duygusal Emek
No full textKitabımızda, günümüz konaklama işletmeleri yönetimi ve pazarlamasının doğasında olan tüketci memnuniyeti ve işletme başarı için önemine inandığımız deneyimsel pazarlama ve duygusal emek konularına odaklanılmıştır. Kitaptan pazarlamanın değişen anlayışı ve deneyimsel pazarlama yaklaşımı, müşteri odaklılık konuları ile duygu ve duygusal emek kavramı, duygusal emek boyutları ve duygusal emek yaklaşımları, turizm işletmelerinde duygusal emek konularını yer verilmiştir. Kitabın araştırma kısmında ise, konaklama işletmelerinde çalışan personelin duygusal emek davranışlarının çalıanların sosyo-demografik özelliklerine göre farklılaşıp farklılaşmadığı soruna cevap aranmaktadır
Spontaneous enterocutaneous fistula: unusual presentation of colon cancer.
No full textSpontaneous enterocutaneous fistula: Unusual presentation of colon cancerBy:Gunay, Y (Gunay, Yusuf)[ 1 ] ; Bircan, H (Bircan, Huseyin)[ 1 ] ; Demiralay, E (Demiralay, Ebru)[ 1 ] ; Sade, C (Sade, Cagri)[ 2 ] ; Emek, E (Emek, Ertan)[ 1 ] ; Demirg, A (Demirg, Alp)[ 1 ] </p
Do Large Retailers Affect Employment? Evidence from an Emerging Economy
No full textThis paper studies the effect of the emergence of large retailers (hypermarkets and department stores) on employment in the commerce sector in the regions of Chile. We use a panel with quarterly data from eleven Chilean regions for the period 1996-2004. Our results indicate that the entry of large retailers produces a discrete increase in employment in the commerce sector in the quarter that the entry occurs. We also find that there is an additional positive effect on employment throughout the year entry occurs, suggesting that suppliers or other parts of the chain of production follow the large retailer into the local market. However, after the first year of the entry there is a partial reversion, suggesting that smaller retailers exit or contract in response to the entry of the large retailer. The net effect on employment of the entry of a large retailer is an increase of 300 jobs.Entry, employment, retail
Distributed algorithms for low stretch spanning trees
No full textGiven an undirected graph with integer edge lengths, we study the problem of approximating the distances in the graph by a spanning tree based on the notion of stretch. Our main contribution is a distributed algorithm in the CONGEST model of computation that constructs a random spanning tree with the guarantee that the expected stretch of every edge is O(log3 n), where n is the number of nodes in the graph. If the graph is unweighted, then this algorithm can be implemented to run in O(D) rounds, where D is the hop-diameter of the graph, thus being asymptotically optimal. In the weighted case, the run-time of our algorithm matches the currently best known bound for exact distance computations, i.e., Õ(min{√nD, √nD1/4 + n3/5 + D}). We stress that this is the first distributed construction of spanning trees leading to poly-logarithmic expected stretch with non-trivial running time
Entry and Prices: Evidence from the Chilean Supermarket Industry
No full textOne of the most significant developments in the last couple of decades in the retail industry has been the emergence of large supermarkets (hypermarkets). The purpose of this paper is to investigate the effect on prices of the entry of a large supermarket into a given location. We use a panel with data from fifteen cities in Chile for the period 1998:I – 2004:IV. The dependent variable is the price of a bundle of 52 food products in each city relative to Santiago. We find that the entry of a hypermarket to a given city reduces prices in that local market by ten percent. Most interestingly, we also find that half of this effect takes place the year before the supermarket actually opens for business.Entry, prices, retail
Low Diameter Graph Decompositions by Approximate Distance Computation
No full textIn many models for large-scale computation, decomposition of the problem is key to efficient algorithms. For distance-related graph problems, it is often crucial that such a decomposition results in clusters of small diameter, while the probability that an edge is cut by the decomposition scales linearly with the length of the edge. There is a large body of literature on low diameter graph decomposition with small edge cutting probabilities, with all existing techniques heavily building on single source shortest paths (SSSP) computations. Unfortunately, in many theoretical models for large-scale computations, the SSSP task constitutes a complexity bottleneck. Therefore, it is desirable to replace exact SSSP computations with approximate ones. However this imposes a fundamental challenge since the existing constructions of such decompositions inherently rely on the subtractive form of the triangle inequality. The current paper overcomes this obstacle by developing a technique termed blurry ball growing. By combining this technique with a clever algorithmic idea of Miller et al. (SPAA 13), we obtain a construction of low diameter decompositions with small edge cutting probabilities which replaces exact SSSP computations by (a small number of) approximate ones. The utility of our approach is showcased by deriving efficient algorithms that work in the Congest, PRAM, and semi-streaming models of computation. As an application, we obtain metric tree embedding algorithms in the vein of Bartal (FOCS 96) whose computational complexities in these models are optimal up to polylogarithmic factors. Our embeddings have the additional useful property that the tree can be mapped back to the original graph such that each edge is "used" only O(log n) times, which is of interest for capacitated problems and simulating Congest algorithms on the tree into which the graph is embedded
KONAKLAMA İŞLETMELERİNDE KİŞİ-ÖRGÜT UYUMU VE DUYGUSAL EMEK DÜZEYLERİ ARASINDAKİ İLIŞKİNİN ANALİZİ
No full textBu çalışmanın amacı, konaklama işletmelerinde Kişi-Örgüt Uyum ve Duygusal Emek düzeyleri arasındaki ilişkiyi incelemektir. Anket çalışması toplam 38 konaklama işletmesinde uygulanmıştır. Araştırmalar Azerbaycan ve Türkiye dahil olmak üzere iki farklı ülkede gerçekleştirilmiştir. SPSS.20 analiz programı kullanarak incelenen toplam 318 anket tamamlandı. Türkiye’de 21 konaklama işletmesinde 205 anket ve Azerbaycan’da 17 konaklama işletmesinde 113 anket toplanmıştır. Araştırmada T testi, tek yönlü ANOVA, Türkiye Post Hoc, Anova Testi, Pearson korelasyon ve regresyon analizi kullanılmıştır. Kişi-Örgüt Uyumu ve Duygusal Emek arasındaki ilişki düzeyi konaklama işletmelerinde farklı sonuçlar göstermektedir. Kişi-Örgüt Uyum düzeyi ile Duygusal Emek düzeyleri arasındaki regresyon ilişkisi anlamlı değildir. (f = 1,977; p = 0,161 ila 0,050). Duygusal Emek’in belirleyicisi olarak bilinen Kişi-Örgüt Uyumunun değişkenlerinin ilişkisinin çok zayıf olduğu bulunmuştur. (R2 = 0.003). Bu, Kişi-Örgüt Uyumu düzeyinin, konaklama işletmelerinde Duygusal Emek düzeyinde olumsuz etkilendiğini göstermektedir (B = -0,107)
Distributed Algorithms for Low Stretch Spanning Trees
No full textGiven an undirected graph with integer edge lengths, we study the problem of approximating the distances in the graph by a spanning tree based on the notion of stretch. Our main contribution is a distributed algorithm in the CONGEST model of computation that constructs a random spanning tree with the guarantee that the expected stretch of every edge is O(log^{3} n), where n is the number of nodes in the graph. If the graph is unweighted, then this algorithm can be implemented to run in O(D) rounds, where D is the hop-diameter of the graph, thus being asymptotically optimal. In the weighted case, the run-time of our algorithm matches the currently best known bound for exact distance computations, i.e., O~ (min{sqrt{n D}, sqrt{n} D^{1 / 4} + n^{3 / 5} + D}). We stress that this is the first distributed construction of spanning trees leading to poly-logarithmic expected stretch with non-trivial running time
Suriyeli Göçmen İşçilerin İstanbul Ölçeğinde Tekstil Sektörü Emek Piyasasına Eklemlenmeleri ve Etkileri
No full textÖz: Bu çalışmanın iki hedefi bulunmaktadır. Bu hedeflerden ilki, Suriye İç Savaşı boyunca Türkiye’ye göç etmek zorunda kalan mültecilerin emek sürecinde edindikleri konumu anlamaktır. İkincisi ise, Türkiyeli işçiler ile Suriyeli işçilerin emek sürecine ve Türkiye’deki geleceklerine dair algılarını karşılaştırmaktır. Bu çerçevede, İstanbul tekstil sektörünü örnek vaka olarak alan çalışmanın veri setini; üç yüz Suriyeli, üç yüz üç Türkiyeli işçi ile gerçekleştirilen anket çalışması, oluşturmaktadır. Kasım 2015-Ocak 2016 arasında gerçekleştirdiğimiz saha çalışmasında Suriyeli işçilerin, kayıt dışılığın ve esnek iş gücünün yaygın olduğu tekstil sektöründe önemli etkilerinin bulunduğu tespit edilmiştir. Bu bağlamda bu çalışma İstanbul ölçeğinde tekstil sektörüne eklemlenen Suriyeli işçilerin demografik yapıları üzerine bir veri seti oluşturmayı, sektörde çalışmakta olan Türkiyeli işçilerle ücret, çalışma koşulları ve iş bulma ve çalışma deneyimleri açısından farklılaştıkları noktaları tespit etmeyi amaçlamaktadır. Anahtar Sözcükler: Suriyeli mülteci, tekstil sektörü, emek süreci, göçmen emeği.</p
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