5646579
Comparing User-assisted and Automatic Query Translation
For the 2002 Cross-Language Evaluation Forum Interactive Track, the University of Maryland team focused on query formulation and reformulation. Twelve people performed a total of forty eight searches in the German document collection using English queries. Half of the searches were with user-assisted query translation, and half with fully automatic query translation. For the user-assisted query translation condition, participants were provided two types of cues about the meaning of each translation: a list of other terms with the same translation (potential synonyms), and a sentence in which the word was used in a translation-appropriate context. Four searchers performed the official iCLEF task, the other eight searched a smaller collection. Searchers performing the official task were able to make more accurate relevance judgments with user-assisted query translation for three of the four topics. We observed that the number of query iterations seems to vary systematically with topic, system, and collection, and we are analyzing query content and ranked retrieval measures to obtain further insight into these variations in search behavior.
12859800
Building an information retrieval test collection for spontaneous conversational speech
Test collections model use cases in ways that facilitate evaluation of information retrieval systems. This paper describes the use of search-guided relevance assessment to create a test collection for retrieval of spontaneous conversational speech. Approximately 10,000 thematically coherent segments were manually identified in 625 hours of oral history interviews with 246 individuals. Automatic speech recognition results, manually prepared summaries, controlled vocabulary indexing, and name authority control are available for every segment. Those features were leveraged by a team of four relevance assessors to identify topically relevant segments for 28 topics developed from actual user requests. Search-guided assessment yielded sufficient inter-annotator agreement to support formative evaluation during system development. Baseline results for ranked retrieval are presented to illustrate use of the collection.
22535159
Interactive Cross-Language Document Selection
The problem of finding documents written in a language that the searcher cannot read is perhaps the most challenging application of cross-language information retrieval technology. In interactive applications, that task involves at least two steps: (1) the machine locates promising documents in a collection that is larger than the searcher could scan, and (2) the searcher recognizes documents relevant to their intended use from among those nominated by the machine. This article presents the results of experiments designed to explore three techniques for supporting interactive relevance assessment: (1) full machine translation, (2) rapid term-by-term translation, and (3) focused phrase translation. Machine translation was found to better support this task than term-by-term translation, and focused phrase translation further improved recall without an adverse effect on precision. The article concludes with an assessment of the strengths and weaknesses of the evaluation framework used in this study and some remarks on implications of these results for future evaluation campaigns.
13917172
iCLEF 2003 at Maryland: Translation Selection and Document Selection
Maryland performed two sets of experiments for the 2003 Cross-Language Evaluation Forum’s interactive track, one focused on interactive selection of appropriate translations for query terms, the second focused on interactive selection of relevant documents. Translation selection was supported using possible synonyms discovered through back translation and two techniques for generating KeyWord In Context (KWIC) examples of usage. The results indicate that searchers typically achieved a similar search effectiveness using fewer query iterations when interactive translation selection was available. For document selection, a complete extract of the first 40 words of each news story was compared to a compressed extract generated using an automated parse-and-trim approach that approximates one way in which people can produce headlines. The results indicate that compressed “headlines” result in faster assessment, but with a 20% relative reduction in the F α= 0.8 search effectiveness measure.
14844222
Summarization Design for Interactive Cross-Language Question Answering
This paper describes an experimental investigation of interactive techniques for cross-language information access. The task was to answer factual questions from a large collection of documents written in a language in which the user has little proficiency. An interactive cross-language retrieval system that included optional user-assisted query translation, display of translated summaries for individual document ranked in order of decreasing degree of match to the user's query, and optional full-text examination of individual documents was provided. Two alternative types of extractive summaries were tried using a systematically varied presentation order, one drawn from a single segment of the translated document and the other drawn from three (usually) shorter segments of the translated document. On average, users were able to correctly answer just 62% of the sixteen assigned questions in an average of 176 seconds per question. Little difference was found between the two summary types for this task in an experiment using eight human subjects. Time on task and the number of query iterations were found to exhibit a positive correlation with question difficulty.
14753351
Making MIRACLEs: Interactive translingual search for Cebuano and Hindi
Searching is inherently a user-centered process; people pose the questions for which machines seek answers, and ultimately people judge the degree to which retrieved documents meet their needs. Rapid development of interactive systems that use queries expressed in one language to search documents written in another poses five key challenges: (1) interaction design, (2) query formulation, (3) cross-language search, (4) construction of translated summaries, and (5) machine translation. This article describes the design of MIRACLE, an easily extensible system based on English queries that has previously been used to search French, German, and Spanish documents, and explains how the capabilities of MIRACLE were rapidly extended to accommodate Cebuano and Hindi. Evaluation results for the cross-language search component are presented for both languages, along with results from a brief full-system interactive experiment with Hindi. The article concludes with some observations on directions for further research on interactive cross-language information retrieval.
17015567
Effect of channel-estimation error on QAM systems with antenna diversity
This paper studies the effect of channel estimation error and antenna diversity on multilevel quadrature amplitude modulation (M-QAM) systems over Rayleigh fading channels. Based on the characteristic function method, a general closed-form bit-error rate (BER) for M-QAM systems is presented. The effect of the inaccurate channel estimation on the performance for pilot-symbol-assisted modulation M-QAM systems with antenna diversity is investigated. Simulation results for M-QAM (M = 4, 16, 64, 256, etc.) show that the analytical method can accurately estimate the system performance. Moreover, numerical results show that with the antenna-diversity technique, the BER performance improves significantly, especially in perfect channel-estimation cases. It is also found that the channel-estimation error limits the benefit of antenna diversity. By increasing the length of the channel estimator and the amplitude of the pilot symbol, more accurate channel estimation can be achieved, so that the BER performance is improved.
21513395
VLSI architecture and implementation for FS1016 CELP decoder with reduced power and memory requirements
Abstract The code-excited linear predictive (CELP) coder is the most effective technique among various linear predictive coding methods for speech compression. Hence, designing a relatively low-cost and low-power CELP decoder chip for the portable systems and wireless digital communication environment becomes increasingly important. This paper presents the VLSI architecture and chip implementation for the FS1016 CELP decoder with reduced power and memory requirements. A single-chip implementation of the CELP decoder drastically reduces the cost and the size of many CELP vocoder systems. The decoder chip can achieve the following: (1) excellent accuracy results due to the accuracy studies for the finite word length, (2) power savings and high-speed operations owing to the combined advantages of pipeline and concurrent processing structures, (3) table size reducing by applying the memoryless realization for stochastic codebook and partial sums technique and (4) specification satisfying the FS1016 CELP coder. Fabricated with 0.8 μm double-metal CMOS technology, the chip contains approximately 13 000 transistors occupying a 6.1 × 6.2 mm2 area. It has been tested to be fully functional at IMS XL-60 tester and is the first working FS1016 CELP 4.8 K decoder chip. In particular, the fixed-point accuracy studies for the CELP decoder are also addressed herein.
2685835
Energy Consumption of Swarm Intelligence inspired Routing Algorithms in MANETs
Swarm Intelligence (SI) inspired routing algorithms have become a research focus in recent years due to their self-organizing nature, which is very suitable to the routing problems in Mobile Ad hoc Networks (MANETs). The network information can be collected and updated in a decentralized and dynamic way through the localized cooperation among these swarm agents. In this paper, we, for the first time, provide a comprehensive comparison about current SI inspired routing algorithms in MANETs in the aspects of network metrics and simulation environment. Then, we make a detailed study about the energy consumption of the SI inspired routing problem in MANETs. Based on this study, we present the selection criterion of the intermediate nodes so as to be energy efficient. Experimental results are provided with reasonable verification.
13018290
Towards Web Mining of Query Translations for Cross-Language Information Retrieval in Digital Libraries
This paper proposes an efficient client-server-based query translation approach to allowing more feasible implementation of cross-language information retrieval (CLIR) services in digital library (DL) systems. A centralized query translation server is constructed to process the translation requests of cross-lingual queries from connected DL systems. To extract translations not covered by standard dictionaries, the server is developed based on a novel integration of dictionary resources and Web mining methods, including anchor-text and search-result methods, which exploit huge amounts of multilingual and wide-scoped Web resources as live bilingual corpora to alleviate translation difficulties, and have been proven particularly effective for extracting multilingual translation equivalents of query terms containing proper names or new terminologies. The proposed approach was implemented in a query translation engine called LiveTrans, which has been shown its feasibility in providing efficient English-Chinese CLIR services for DL.
789503
Exploiting the Web as the multilingual corpus for unknown query translation
target languages. To facilitate a cross-language information retrieval (CLIR) service in digital library systems, it is important to develop a powerful query translation engine. This must be able to automatically translate users’ queries from multiple source languages to the target languages that the systems accept. Conventional approaches to CLIR can be divided into two groups: dictionary-based and corpora-based. A dictionarybased approach (Ballesteros & Croft, 1997) utilizes a simple translation dictionary in which each query term is looked up and translated into its corresponding terms in the target language. However, terms may have multiple ambiguous meanings and many new unknown terms that are not covered in the dictionary cannot be translated. Corpora-based approach (Nie, Isabelle, Simard & Durand, 1999) incorporates multilingual corpus where texts in different languages are collected for translation purpose. Either comparable texts (Fung & Yee, 1998) or parallel texts (Nie et al., 1999) can be used as the multilingual corpus. Parallel texts contain bilingual sentences, from which word or phrase translations can be extracted by appropriate sentence alignment methods (Gale & Church, 1993). Comparable texts share similar concepts in content, but do not necessarily show alignment correspondence for translation. Because there is a fundamental word mismatch problem that queries and documents might not share the same words, the basic assumption of such approaches is that as queries get longer, the severity of the problem tends to decrease. Query expansion techniques (Ballesteros & Croft, 1997) can therefore be used to enrich query terms not covered in documents. However, these approaches present some fundamental difficulties for digital libraries that wish to support practical CLIR services. First, most of existing digital libraries contain only monolingual text collections; hence, there is no bilingual corpus for cross-lingual training. Second, real Exploiting the Web as the Multilingual Corpus for Unknown Query Translation