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An Exploratory Study of Hedging in Chinese ESL Learners' Academic
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作者 陈玮 《海外英语》 2013年第11X期41-43,49,共4页
Hedging, referring to the use of various lexical and syntactic features modifying and mitigating propositions and claims, is extensively employed in effective academic writing. However, the use of hedges seems to be q... Hedging, referring to the use of various lexical and syntactic features modifying and mitigating propositions and claims, is extensively employed in effective academic writing. However, the use of hedges seems to be quite problematic for lots of Chinese ESL learners. In view of the situation, this study explores the use of hedges in academic abstracts by a group of undergraduate English majors in a university in Hainan Province. After analyzing data from a corpus and interviews, several problems have been found in the use of hedging devices of these students, and relevant implications have been drawn to the teaching of hedging in the context, which can help the students produce more effective academic writing and to achieve greater university success. 展开更多
关键词 hedgING use of hedgES ACADEMIC abstracts problems
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Hedge Trimmer句子压缩技术的算法实现及改进 被引量:1
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作者 景秀丽 《沈阳师范大学学报(自然科学版)》 CAS 2012年第4期519-524,共6页
压缩技术旨在模拟人类的文本概括和信息提取能力。句子压缩技术是自动生成能够保留原句核心内容的,合乎语法的,语义连贯的简短句子。文章分析了英文句子压缩技术中基于句法分析的Hedge Trimmer压缩技术,讨论了相关压缩理论,探索其压缩... 压缩技术旨在模拟人类的文本概括和信息提取能力。句子压缩技术是自动生成能够保留原句核心内容的,合乎语法的,语义连贯的简短句子。文章分析了英文句子压缩技术中基于句法分析的Hedge Trimmer压缩技术,讨论了相关压缩理论,探索其压缩过程并用类C语言进行算法实现。提出了好的压缩句应该至少满足以下3个标准:第一是保留原句的核心内容,第二是具有正确的语法,第三是压缩长度合理。在算法的评估工作中,从DUC 2003语料库中选取了624个原始句子和对应的人工压缩句,与Hedge Trimmer压缩算法自动生成的压缩句进行对照分析。发现5种压缩效果不理想的情况,分析其原因并提出了改进策略。最后,通过实例对改进算法生成的压缩句和原来算法生成的压缩句进行对比评估,证明了改良算法能够获得更理想的压缩句。在英文句子压缩领域,改良的Hedge Trimmer句子压缩算法值得推广和应用。 展开更多
关键词 句子压缩 hedgE Trimmer算法 评估 改进
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Enabling weakened hedges in linguistic multi-criteria decision making
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作者 王海 徐泽水 《Journal of Southeast University(English Edition)》 EI CAS 2016年第1期125-131,共7页
A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based o... A semantics-based model is proposed to enable weakened hedges, such as "more or less" and "roughly" in the context of linguistic multi-criteria decision making. First, the resemblance relations are defined based on the semantics of terms on the domain. Then, the hedges can be represented after the upper and loose upper approximations of a linguistic term are derived. Accordingly, some compact formulae can be derived for the semantics of linguistic expressions with hedges. Parameters in these formulae are objectively determined according to the semantics of original terms. The proposed model presents a more natural way to express the decision information under uncertainties and its semantics is clear. The proposed model is clarified by solving the problem of evaluation and selection of sustainable innovative energy technologies. Computational results demonstrate that the model can deal with various uncertainties of the problem. Finally, the model is compared with existing techniques and extended to the case when the semantics of terms are represented by trapezoidal fuzzy numbers. 展开更多
关键词 decision making multi-criteria decision making linguistic term sets linguistic hedges similarity relation
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论言语中的Hedges
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作者 李茹 《黔南民族师范学院学报》 2005年第1期67-70,共4页
Hedge是一种极具特殊性的语言表达,许多语言学家研究发现它广泛地用于女性语体中。从语用角度来讲,它也是一种极其重要的表达手段,并充分体现言语交际中应遵守的合作原则和礼貌原则,同时在特定的语境下蓄含特殊的意义,它的主要用途。
关键词 hedgE 合作原则 礼貌原则
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Hedge fund replication using strategy specific factors
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作者 Sujit Subhash David Enke 《Financial Innovation》 2019年第1期179-197,共19页
Hedge funds have traditionally served wealthy individuals and institutional investors with the promise of delivering protection of capital and uncorrelated positive returns irrespective of market direction,allowing th... Hedge funds have traditionally served wealthy individuals and institutional investors with the promise of delivering protection of capital and uncorrelated positive returns irrespective of market direction,allowing them to better manage portfolio risk.However,the financial crisis of 2008 has heightened investor sensitivity to the high fees,illiquidity,lack of transparency,and lockup periods typically associated with hedge funds.Hedge fund replication products,or clones,seek to answer these challenges by providing daily liquidity,transparency,and immediate exposure to a desired hedge fund strategy.Nonetheless,although lowering cost and adding simplicity by using a common set of factors,traditional replication products might offer lower risk-reward performance compared to hedge funds.This research explores hedge fund replication further by examining the importance of constructing clones with specific factors relevant to each hedge fund strategy,and then compares the strategy specific clone risk and reward performance against both actual hedge fund performance and hedge fund clones constructed using a more general set of common factors.Testing shows that using strategy specific factors to replicate common hedge fund strategies can offer superior risk-reward performance compared to previous general model clones. 展开更多
关键词 hedge funds hedge fund replication Regression Trading strategies Strategy specific factors
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A Longitudinal Study of Hedges in Different Moves of EMRAs
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作者 寇英 《海外英语》 2013年第4X期228-231,共4页
This paper investigates the evolutionary change in the OF(OF) of hedges in different moves of EMRAs(EMRAs).Two corpora are established for longitudinal study,with Corpus A consisting of EMRAs from 1990-1994 and Corpus... This paper investigates the evolutionary change in the OF(OF) of hedges in different moves of EMRAs(EMRAs).Two corpora are established for longitudinal study,with Corpus A consisting of EMRAs from 1990-1994 and Corpus B from 2005-2009.Generally,no significant change has been found in overall use of hedges.However,apart from move 6,7 and 10,we have found some interesting changes in the other moves.On the one hand,the OF of hedges in move 1,move 3,move 4 and move 5 shows a significant increase.On the other hand,the OF of hedges in move 2,8,9 and move 11 show a significant decrease. 展开更多
关键词 longitudinal STUDY hedgES MOVES EMRAs
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基于PML及Hedge的物联网异构信息集成处理模型 被引量:6
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作者 王桐 赵春晖 焉晓贞 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2011年第2期301-304,共4页
针对物联网前端感知信息的海量性和异构性问题,提出物联网异构信息集成处理体系结构,包括引入物联网异构数据交换标准并提出物联网异构信息处理方法.物联网异构信息集成方案在感知层、传输层及应用层进行.在感知层,模型对不同传感器或R... 针对物联网前端感知信息的海量性和异构性问题,提出物联网异构信息集成处理体系结构,包括引入物联网异构数据交换标准并提出物联网异构信息处理方法.物联网异构信息集成方案在感知层、传输层及应用层进行.在感知层,模型对不同传感器或RFID的信息进行归一化及数据清洗;在传输层和应用层,模型对这些异构物联网信息进行信息融合及智能处理.提出了新的基于Hedge文法的高效过滤算法以提高匹配引擎处理海量数据的能力. 展开更多
关键词 物联网 集成 PML 森林文法
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Tracking market and non-traditional sources of risks in procyclical and countercyclical hedge fund strategies under extreme scenarios:a nonlinear VAR approach 被引量:1
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作者 François-Éric Racicot Raymond Théoret 《Financial Innovation》 2022年第1期696-751,共56页
The subprime crisis was quite damaging for hedge funds.Using the local projection method(Jordà2004,2005,2009),we forecast the dynamic responses of the betas of hedge fund strategies to macroeconomic and financial... The subprime crisis was quite damaging for hedge funds.Using the local projection method(Jordà2004,2005,2009),we forecast the dynamic responses of the betas of hedge fund strategies to macroeconomic and financial shocks—especially volatility and illiquidity shocks—over the subprime crisis in order to investigate their market timing activities.In a robustness check,using TVAR(Balke 2000),we simulate the reaction of hedge fund strategies’betas in extreme scenarios allowing moderate and strong adverse shocks.Our results show that the behavior of hedge fund strategies regarding the monitoring of systematic risk is highly nonlinear in extreme scenarios—especially during the subprime crisis.We find that countercyclical strategies have an investment technology which differs from procyclical ones.During crises,the former seek to capture non-traditional risk premia by deliberately increasing their systematic risk while the later focus more on minimizing risk.Our results suggest that the hedge fund strategies’betas respond more to illiquidity uncertainty than to illiquidity risk during crises.We find that illiquidity and VIX shocks are the major drivers of systemic risk in the hedge fund industry. 展开更多
关键词 hedge fund PROCYCLICALITY Illiquidity risk shock Illiquidity uncertainty shock Local projection model TVAR Optimal forecast Measurement errors
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COVID‑19 pandemic and the crude oil market risk:hedging options with non‑energy financial innovations 被引量:1
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作者 Afees A.Salisu Kingsley Obiora 《Financial Innovation》 2021年第1期722-740,共19页
This study examines the hedging effectiveness of financial innovations against crude oil investment risks,both before and during the COVID-19 pandemic.We focus on the non-energy exchange traded funds(ETFs)as proxies f... This study examines the hedging effectiveness of financial innovations against crude oil investment risks,both before and during the COVID-19 pandemic.We focus on the non-energy exchange traded funds(ETFs)as proxies for financial innovations given the potential positive correlation between energy variants and crude oil proxies.We employ a multivariate volatility modeling framework that accounts for important statistical features of the non-energy ETFs and oil price series in the computation of optimal weights and optimal hedging ratios.Results show evidence of hedging effectiveness for the financial innovations against oil market risks,with higher hedging performance observed during the pandemic.Overall,we show that sectoral financial innovations provide resilient investment options.Therefore,we propose that including the ETFs in an investment portfolio containing oil could improve risk-adjusted returns,especially in similar financial crisis as witnessed during the pandemic.In essence,our results are useful for investors in the global oil market seeking to maximize risk-adjusted returns when making investment decisions.Moreover,by exploring the role of structural breaks in the multivariate volatility framework,our attempts at establishing robustness for the results reveal that ignoring the same may lead to wrong conclusions about the hedging effectiveness. 展开更多
关键词 Pandemics Financial innovations Energy markets hedgING Optimal portfolio
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Improving Accuracy of Estimating Two-Qubit States with Hedged Maximum Likelihood 被引量:1
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作者 殷琪 项国勇 +1 位作者 李传锋 郭光灿 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第3期1-5,共5页
As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately... As a widely used reconstruction algorithm in quantum state tomography, maximum likelihood estimation tends to assign a rank-deficient matrix, which decreases estimation accuracy for certain quantum states. Fortunately, hedged maximum likelihood estimation (HMLE) [Phys. Rev. Lett. 105 (2010)200504] was proposed to avoid this problem. Here we study more details about this proposal in the two-qubit case and further improve its performance. We ameliorate the HMLE method by updating the hedging function based on the purity of the estimated state. Both performances of HMLE and ameliorated HMLE are demonstrated by numerical simulation and experimental implementation on the Werner states of polarization-entangled photons. 展开更多
关键词 MLE Improving Accuracy of Estimating Two-Qubit States with hedged Maximum Likelihood
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High Altitude Frogs (Rana kukonoris) Adopt a Diversified Bethedging Strategy in the Face of Environmental Unpredictability 被引量:1
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作者 Wei CHEN Liqing PENG +3 位作者 Lichun JIANG David A.PIKE Christopher R.FRIESEN Gregory BROWN 《Asian Herpetological Research》 SCIE CSCD 2018年第1期43-49,共7页
Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environm... Environmental unpredictability can influence strategies of maternal investment among eggs within a clutch. Models predict that breeding females should adopt a diversified bet-hedging strategy in unpredictable environments, but empirical field evidence from Asia is scarce. Here we tested this hypothesis by exploring spatial patterns in egg size along an altitudinal gradient in a frog species (Rana kukunoris) inhabiting the Tibetan Plateau. Within-clutch variability in egg size increased as the environment became variable (e.g., lower mean monthly temperature and mean monthly rainfall at higher altitudes), and populations in environments with more unpredictable rainfall produced eggs that were smaller and more variable in size. We provide support for a diversified bet-hedging strategy in high-altitude environments, which experience dynamic weather patterns and therefore are of unpredictable environmental quality. This strategy may be an adaptive response to lower environmental quality and higher unpredictable environmental variance. Such a strategy should increase the likelihood of breeding success and maximize maternal lifetime fitness by producing offspring that are adapted to current environmental conditions. We speculate that in high-altitude environments prone to physical disturbance, breeding females are unable to consistently produce the optimal egg size due to physiological constraints imposed by environmental conditions (e.g., duration of the active season, food availability). Species and populations whose breeding strategies are adapted to cope with uncertain environmental conditions by adjusting offspring size and therefore quality show a remarkable degree of ability to cope with future climatic changes. 展开更多
关键词 altitude bet-hedging strategy environmental quality egg size within-clutch variation unpredictable environment
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Hedging in Discourse Analysis
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作者 肖欣 《海外英语》 2015年第12期232-234,共3页
In this article an attempt to enhance the awareness of hedging use in discourse analysis and academic writing is madeby analyzing hedges employed in two comparable texts.The discourse analysis is conducted from"c... In this article an attempt to enhance the awareness of hedging use in discourse analysis and academic writing is madeby analyzing hedges employed in two comparable texts.The discourse analysis is conducted from"content-oriented"hedges and"reader-oriented"hedges.The article suggests that hedging can dampen utterances and statements,weaken the force of what onesays and show politeness to the listeners or readers,which varies from different discourse styles of various genres.discourse marker;hedging;research article;news 展开更多
关键词 DISCOURSE MARKER hedgING research ARTICLE NEWS report
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A Corpus-based Contrastive Study on Hedging in English Business Cor-respondences between Chinese English Learners and Native Speakers
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作者 周敏仪 《海外英语》 2013年第1X期261-262,共2页
This is a corpus-based contrastive study projected to find out the differences in using hedges in English business corre spondences between Chinese English learners and native speakers.
关键词 hedgES CORPUS CONTRASTIVE study NS CEL
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Pragmatic Functions of Hedges in Business Letters
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作者 刘璐璐 《海外英语》 2013年第14期249-251,共3页
The aim of the present research to explore the hedges used English business letters. Several samples have been chosen to make qualitative study in order to achieve the goal of answering the following question: what ar... The aim of the present research to explore the hedges used English business letters. Several samples have been chosen to make qualitative study in order to achieve the goal of answering the following question: what are the pragmatic functions of hedges being used in business letters? After analyzing the samples, the conclusion could be came that the employment of hedges in business letters has three pragmatic functions-giving the right amount of information, being polite and self-production. 展开更多
关键词 hedgES BUSINESS LETTERS PRAGMATIC FUNCTION
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The Relative Ordering of Optimal Hedging Points in a Class of Failure Prone Manufacturing Systems
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作者 俞新贞 宋文忠 《Journal of Southeast University(English Edition)》 EI CAS 1997年第1期114-117,共4页
For a class of manufacturing systems with homogeneous Markov machine failure rates,the stationary probability distribution of the part surplus can be calculated for given tentative values of hedging points. Some prope... For a class of manufacturing systems with homogeneous Markov machine failure rates,the stationary probability distribution of the part surplus can be calculated for given tentative values of hedging points. Some properties on the ordering of optimal hedging points are obtained. 展开更多
关键词 MANUFACTURING SYSTEM MARKOV chain transition rate SYSTEM state hedgING point policy
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Insiders' Hedging for Jump Diffusion Processes with Applications to Index Tracking
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作者 苏小囡 王伟 王文胜 《Journal of Donghua University(English Edition)》 EI CAS 2011年第6期571-575,共5页
The hedging problem for insiders is very important in the financial market.The locally risk minimizing hedging was adopted to solve this problem.Since the market was incomplete,the minimal martingale measure was chose... The hedging problem for insiders is very important in the financial market.The locally risk minimizing hedging was adopted to solve this problem.Since the market was incomplete,the minimal martingale measure was chosen as the equivalent martingale measure.By the F-S decomposition,the expression of the locally risk minimizing strategy was presented.Finally,the local risk minimization was applied to index tracking and its relationship with tracking error variance (TEV)-minimizing strategy was obtained. 展开更多
关键词 jump diffusion processes local risk minimization insiders’ hedging index tracking
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Option Pricing and Hedging under a Markov Switching Lévy Process Model
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作者 宋瑞丽 王波 《Chinese Quarterly Journal of Mathematics》 2017年第1期66-78,共13页
In this paper, we consider a Markov switching Lévy process model in which the underlying risky assets are driven by the stochastic exponential of Markov switching Lévy process and then apply the model to opt... In this paper, we consider a Markov switching Lévy process model in which the underlying risky assets are driven by the stochastic exponential of Markov switching Lévy process and then apply the model to option pricing and hedging. In this model, the market interest rate, the volatility of the underlying risky assets and the N-state compensator,depend on unobservable states of the economy which are modeled by a continuous-time Hidden Markov process. We use the MEMM(minimal entropy martingale measure) as the equivalent martingale measure. The option price using this model is obtained by the Fourier transform method. We obtain a closed-form solution for the hedge ratio by applying the local risk minimizing hedging. 展开更多
关键词 Markov chain model MEMM Lévy process option pricing hedgING
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Mean-Variance Hedging for General Claims in an Incomplete Market: Numeraire Method
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作者 王桂兰 叶中行 《Journal of Shanghai Jiaotong university(Science)》 EI 2003年第2期175-178,共4页
This paper considered the problem of hedging a European call (put) option for a diffusion model where the asset price is influenced by n uncertain factors. The market is thus incomplete implying that perfect hedging i... This paper considered the problem of hedging a European call (put) option for a diffusion model where the asset price is influenced by n uncertain factors. The market is thus incomplete implying that perfect hedging is not possible. To derive a hedging strategy, it follows the approach based on the idea of hedging under a mean-variance criterion suggested by Schweizer. A very simple solution of this hedging problem by using the numeraire method was presented and some examples with explicit solutions were given. 展开更多
关键词 Mean-variance hedging incomplete market NUMERAIRE European options
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Power Purchase Model of Provincial Grids Based on Diverse Energy Coordination Hedging Optimization
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作者 Dunnan Liu Yujie Xu +3 位作者 Weimin Zeng Jiangping Liu Min Fan Xinming Liu 《Journal of Power and Energy Engineering》 2014年第4期463-469,共7页
Under the background of energy conservation, the grid companies should give priority to consumptive hydropower, wind power and other clean electricity to fulfill their social responsibility and promote the carbon emis... Under the background of energy conservation, the grid companies should give priority to consumptive hydropower, wind power and other clean electricity to fulfill their social responsibility and promote the carbon emission reduction in power industry. But under the current power purchase mode, grid companies must first perform the contract. This is extremely uneconomical and not environmentally friendly. Based on hedging theory, this paper proposes a power purchase optimization model using the strategy of “compression and compensation”. If outer price is lower than the contract price, the grid can compress contract power appropriately, leaving more space for purchasing electricity;if outer price is not attractive enough, the grid should timely improve contract proportion, compensating the deviations of contract caused by "compression". Based on the strategy of "compression and compensation", it can effectively reduce the abandoned wind and water, enhance the economic and social benefits of provincial power grid. 展开更多
关键词 Power PURCHASE OPTIMIZATION hedgING "Compression and Compensation" Large-Scale System Decomposition-Coordination
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On discrete time hedging errors in a fractional Black-Scholes model
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作者 WANG Wen-sheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第2期211-224,共14页
In this paper we investigate asymptotic behavior of error of a discrete time hedging strategy in a fractional Black-Scholes model in the sense of Wick-ItS-Skorohod integration. The rate of convergence of the hedging e... In this paper we investigate asymptotic behavior of error of a discrete time hedging strategy in a fractional Black-Scholes model in the sense of Wick-ItS-Skorohod integration. The rate of convergence of the hedging error due to discrete-time trading when the true strategy is known for the trader, is investigated. The result provides new statistical tools to study and detect the effect of the long-memory and the Hurst parameter for the error of discrete time hedging. 展开更多
关键词 discrete time hedging Wick-Itö-Skorohod integral rate of convergence weak convergence incomplete market fractional Brownian motion replicate Black-Scholes model
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