1,739 research outputs found
チュウゴク キギョウ ノ タイニチ チョクセツ トウシ ノ ドウコウ ト センリャクテキ カダイ
大阪大學中國文化論壇 討論文件Discussion Papers in Contemporary China Studies, Osaka University Forum on China本稿は、急増する中国企業の対日投資の背景とビジネスモデルをめぐる戦略的課題を取り上げる。1.リーマンショック後の世界経済を牽引する主役として中国をはじめとするBrics の役割増大が続いている。内需拡大による世界貿易基調の維持にとどまらず,潤沢な外貨準備高と企業成長を背景に国家資本による国際資源投資や海外企業のM&A なども活発化の様相を見せている。2010 年における全世界の対外直接投資額は1 兆1220 億ドルと推計され,そのうち中国大陸の対外投資分は約590 億ドルで、全体の5.3%に過ぎないが,企業の海外進出を奨励する「走出去政策」(Go Overseas)が登場した1999 年以降,8 年連続の増加であり,①量的拡大、②産業高度化に資する企業経営資源の質的拡充、③アジア新興国市場開拓が想定されるなか,今後の世界経済回復にともなってこの比率がさらに膨らむ可能性は十分にある。2.中国のアジア向け直接投資はASEAN 中心で筆頭はシンガポールの金融センター活用の企業M&Aであるが,インドシナ半島やミャンマー等のメコン河流域での資源開発やインフラ整備への投資も急増している。3.帝国データバンク社の資料によれば中国企業が出資する日本企業は2010年6月の時点で611社、5年前の233社に比べて約2.5倍に増加した。業種別では「卸売業」が323 社(52.9%)でトップ。5年前に比べて「製造業」「サービス業」が3倍に増加した。大型投資案件も出始め、自治体の外資誘致の拡大と相乗して拡大の傾向にある。4.通常、海外直接投資もしくは多国籍企業のビジネスモデルに関しては,資金が潤沢、投資先での絶対的優位性の確保,先進国から途上国への投資ルートが条件とされ,直接投資(Foreign Direct Investment)の結果,以下の特色が認められる。外国法人の経営支配が目的、法人の発行済み株式の10%以上を保有、その主体は多国籍企業:MultinationalEnterpriseMNE)、カネのみならず、モノ、ヒト、技術、ノウハウなどの経営資源の国際移転、企業文化の移転、文化的変容も伴なう。日本における中国企業の投資目的はなにか?中国の市場ポテンシャルと日本の高度技術・ブランド力・経営ノウハウの補完関係は投資事業の推進過程において達成されうるか?今後の企業対日戦略の課題はなにか?本稿ではいくつかのケース・スターディーを手掛かりに検証作業を進める
A User-Centered Concept Mining System for Query and Document Understanding at Tencent
Concepts embody the knowledge of the world and facilitate the cognitive
processes of human beings. Mining concepts from web documents and constructing
the corresponding taxonomy are core research problems in text understanding and
support many downstream tasks such as query analysis, knowledge base
construction, recommendation, and search. However, we argue that most prior
studies extract formal and overly general concepts from Wikipedia or static web
pages, which are not representing the user perspective. In this paper, we
describe our experience of implementing and deploying ConcepT in Tencent QQ
Browser. It discovers user-centered concepts at the right granularity
conforming to user interests, by mining a large amount of user queries and
interactive search click logs. The extracted concepts have the proper
granularity, are consistent with user language styles and are dynamically
updated. We further present our techniques to tag documents with user-centered
concepts and to construct a topic-concept-instance taxonomy, which has helped
to improve search as well as news feeds recommendation in Tencent QQ Browser.
We performed extensive offline evaluation to demonstrate that our approach
could extract concepts of higher quality compared to several other existing
methods. Our system has been deployed in Tencent QQ Browser. Results from
online A/B testing involving a large number of real users suggest that the
Impression Efficiency of feeds users increased by 6.01% after incorporating the
user-centered concepts into the recommendation framework of Tencent QQ Browser.Comment: Accepted by KDD 201
New Bounds on Augmenting Steps of Block-Structured Integer Programs
Iterative augmentation has recently emerged as an overarching method for solving Integer Programs (IP) in variable dimension, in stark contrast with the volume and flatness techniques of IP in fixed dimension. Here we consider 4-block n-fold integer programs, which are the most general class considered so far. A 4-block n-fold IP has a constraint matrix which consists of n copies of small matrices A, B, and D, and one copy of C, in a specific block structure. Iterative augmentation methods rely on the so-called Graver basis of the constraint matrix, which constitutes a set of fundamental augmenting steps. All existing algorithms rely on bounding the ??- or ?_?-norm of elements of the Graver basis. Hemmecke et al. [Math. Prog. 2014] showed that 4-block n-fold IP has Graver elements of ?_?-norm at most ?_FPT(n^{2^{s_D}}), leading to an algorithm with a similar runtime; here, s_D is the number of rows of matrix D and ?_FPT hides a multiplicative factor that is only dependent on the small matrices A,B,C,D, However, it remained open whether their bounds are tight, in particular, whether they could be improved to ?_FPT(1), perhaps at least in some restricted cases.
We prove that the ?_?-norm of the Graver elements of 4-block n-fold IP is upper bounded by ?_FPT(n^{s_D}), improving significantly over the previous bound ?_FPT(n^{2^{s_D}}). We also provide a matching lower bound of ?(n^{s_D}) which even holds for arbitrary non-zero lattice elements, ruling out augmenting algorithm relying on even more restricted notions of augmentation than the Graver basis. We then consider a special case of 4-block n-fold in which C is a zero matrix, called 3-block n-fold IP. We show that while the ?_?-norm of its Graver elements is ?(n^{s_D}), there exists a different decomposition into lattice elements whose ?_?-norm is bounded by ?_FPT(1), which allows us to provide improved upper bounds on the ?_?-norm of Graver elements for 3-block n-fold IP. The key difference between the respective decompositions is that a Graver basis guarantees a sign-compatible decomposition; this property is critical in applications because it guarantees each step of the decomposition to be feasible. Consequently, our improved upper bounds let us establish faster algorithms for 3-block n-fold IP and 4-block IP, and our lower bounds strongly hint at parameterized hardness of 4-block and even 3-block n-fold IP. Furthermore, we show that 3-block n-fold IP is without loss of generality in the sense that 4-block n-fold IP can be solved in FPT oracle time by taking an algorithm for 3-block n-fold IP as an oracle
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