373 research outputs found
Die Geschichtlichkeit des Menschen und die Geschichte des Seins
No full textIn der vorliegenden Arbeit untersucht Cheong, wie Heidegger von der Seinsfrage her auf die Frage nach der Geschichtlichkeit des Menschen und der Geschichte des Seins antwortet.Geschichte und Geschichtlichkeit werden von Heidegger stets im Zusammenhang mit der Seinsfrage und somit mit der Zeitfrage gedacht. Wenn so sein geschichtliches Denken einen inneren Zusammenhang mit der Frage nach dem Sein und der Zeit hat, ist es unumgänglich, die Geschichtlichkeit des Menschen und die Geschichte des Seins von der Seins- und Zeitfrage her zu fassen. Dies gilt sowohl für sein frühes Denken in der transzendental-ontologischen Blickbahn wie auch für sein späteres Denken, das sich in der seinsgeschichtlich-ereignishaften Blickbahn entfaltet
Postfilter for multi-channel speech enhancement integrating spatial and spectro-temporal information
No full textSpeech enhancement aims to suppress the noise and improve the quality and intelli- gibility of degraded speech signals in a variety of acoustic environments. In contrast to single channel speech enhancement, which exploits the spectro-temporal information of the input signal to estimate clean speech, multichannel speech enhancement can further leverage spatial cues obtained from multiple microphones to achieve improved performance. There has been a growing demand for speech enhancement using micro- phone arrays in speech processing applications such as automatic speech recognition, mobile communications, meeting summarization and hearing aids. One of the popular configurations for multichannel speech enhancement is to apply a spatial filter exploit- ing spatial diversity of sound sources, and then apply a single-channel postfilter to the output of the spatial filter. One of the popular configurations in multichannel speech enhancement involves applying a spatial filter, such as the minimum variance distor- tionless response (MVDR) beamformer, that exploits the spatial diversity of sound sources, followed by a single-channel postfilter to further reduce residual noise. In this dissertation, we propose methods that incorporate multichannel information to construct postfilters aiming to effectively utilize spatial and spectro-temporal infor- mation. First, we propose a statistical model-based postfilter for dual-channel speech enhancement, combining a statistical model-based single channel noise power spectral density (PSD) estimator and a coherence-based dual channel noise PSD estimator with the a posteriori speech presence probability (SPP). We model the coherence-based a posteriori SPP as a simple function of the magnitude of coherence between two micro- phone signals and combine it with a single-channel SPP based on statistical models. The coherence-based estimator for the PSD of the noise remaining in the beamformer output in the presence of speech is derived using the pseudo-coherence considering the effect of the beamformers, which is used to construct the coherence-based noise PSD estimator. Then, the final noise PSD estimator is obtained by combining the coherence- based and statistical model-based noise PSD estimators with the proposed SPP. The spectral gain function is also modified, incorporating the proposed SPP. Experimental results demonstrate that the proposed method led to more accurate noise PSD estima- tion and perceptual evaluation of speech quality (PESQ) scores in various diffuse noise environments, and did not degrade the speech quality under the presence of directional interference, although the proposed method utilizes the coherence information. Secondly, we propose a deep neural network (DNN)-based postfitler for multichan- nel speech enhancement, integrating DNN-based parameter estimation for multichannel speech enhancement utilizing parameters estimated from the beamforming stage in the parameter estimation for the postfilter. Specifically, the a posteriori SPP, the speech PSD, and the noise PSD in estimated in the beamforming stage are utilized to im- prove the parameter estimation in the postfiltering stage. We also adopt the dual-path conformer structure with an encoder and decoders to enhance the performance. Ex- perimental results show that the proposed method marked the best wideband PESQ scores on the CHiME-4 dataset among all compared methods. ©2025 Sein Cheong ALL RIGHTS RESERVED – iii –|음성 향상 기술은 다양한 음향 환경에서 잡음을 억제하고 음성 신호의 품질과 명료 성을 개선하는 기술로, 최근 음성 인식, 모바일 통신 및 보청기 등 실제 응용 분야에서 수요가 지속적으로 증가하고 있다. 입력 신호의 스펙트럼-시간 정보만을 활용하는 단일 채널음성향상기법과달리,다채널음성향상기법은여러마이크로폰에서얻어진공간 정보를 추가적으로 활용함으로써 더욱 우수한 성능을 얻을 수 있다. 다채널 음성 향상의 대표적 구성 방법 중 하나는 최소 분산 비왜곡 응답(minimum-variance distortionless response, MVDR) 빔포머(beamformer)와 같이 음원의 공간 정보를 활용하는 공간 필터 (spatial filter)를 먼저 적용하고, 공간 필터의 출력에 단일 채널 후처리 필터(postfitler) 를 추가로 적용하여 잔여 잡음을 제거하는 방식이다. 본 학위 논문에서는 공간 정보와 시간-주파수 정보를 효과적으로 결합한 다채널 음 성 향상 후처리 기법들을 제안하였다. 먼저 두 채널 음성 향상을 위한 통계 모델 기반 후처리 기법을 제안하였다. 본 방법은 통계 모델 기반의 단일 채널 잡음 전력 스펙트럼 밀도(power spectrum density, PSD) 추정기와 두 마이크로폰 신호의 일관성(coherence) 을 이용한 두 채널 잡음 PSD 추정기를 결합한다. 두 마이크로폰 신호 간의 coherence 의 크기를 활용하여 coherence기반 사후 음성 존재 확률(a posteriori speech presence probability, SPP)을 모델링하고 이를 통계 모델 기반의 단일 채널 a posteriori SPP를 결합하였다. 그 다음, 음성 존재 불확실성을 반영하여 coherence기반의 두 채널 잡음 PSD 추정기를 유도하고, 이를 통계 모델 기반 잡음 PSD 추정기와 a posteriori SPP를 활용하여 결합한다. 최종적으로 결합된 잡음 PSD 추정치와 a posteriori SPP를 이용하 여최적변형로그스펙트럼진폭(optimally modified log-spectral amplitude, OM-LSA) 이득 함수를 계산하여 후처리 필터로 사용하였다. 이를 통해 빔포머 출력 신호에 남아있 는 잡음의 PSD 추정 정확도를 높였으며, 다양한 확산 잡음(diffuse noise) 환경에서 음성 품질(PESQ 점수)을 향상시켰다. 두 번째로는 심층 신경망(deep neural network, DNN) 기반 다채널 음성 향상 후처 리 기법을 제안하였다. 본 방법에서는 빔포밍 단계에서 추정된 음성 PSD, 잡음 PSD, a posteriori SPP 등의 파라미터를 후처리 단계의 파라미터 추정 과정에 통합하여 공간 정보와 스펙트럼-시간 정보를 종합적으로 활용하였다. 추가로, dual-path conformer 네 트워크 구조를 도입하여 파라미터 추정의 정확도와 계산 효율성을 동시에 향상시켰다. 실험 결과, CHiME-4 데이터셋에서 제안한 방법이 기존 방법 대비 가장 높은 음성 품질 (PESQ 점수)을 나타냈다. 결론적으로, 본 논문에서 제안한 기법들은 단일 채널 및 다채널 음성 향상 기술과 딥러닝 접근법을 효과적으로 결합하여 낮은 계산 복잡도에서 강건한 성능을 달성하였 다. 이에 따라 제안된 방법들은 음성 인식, 모바일 통신, 보청기 등의 실제 음성 처리 분야에서 실질적으로 활용될 수 있을 것으로 기대된다. ©2025 정 세 인 ALL RIGHTS RESERVEDDoctorAbstract (English) i
Abstract (Korean) iv
List of Contents vi
List of Tables viii
List of Figures ix
1 Introduction 1
1.1 Introduction 1
1.2 Outline of the Dissertation 3
2 Postfilter for Multichannel Speech Enhancement Using Coherence
and Statistical Model-based Noise Estimation 5
2.1 Introduction 5
2.2 System Overview and Review of SPP-Based Noise Estimation 8
2.2.1 Problem Formulation and System Overview 8
2.2.2 Single Channel Noise PSD Estimator Based on Speech Presence
Probability 10
2.3 Postfilter for dual channel speech enhancement utilizing noise estimation
based on coherence and statistical model 12
2.3.1 Modeling of a Posteriori SPP Based on Coherence 14
2.3.2 Proposed Dual channel Noise PSD Estimator Based on Coherence 16
2.3.3 Combining Noise PSD Estimates and Gain Calculation 22
2.4 Experimental and Results 23
2.4.1 Experimental Configurations 23
2.4.2 Experimental Results 27
3 Integrated DNN-based Parameter Estimation for Multichannel Speech
Enhancement 39
3.1 Introduction 39
3.2 Review of DNN-based Parameter Estimation 41
3.2.1 MVDR Beamforming and Postfiltering 41
– vi –
3.2.2 Parameter Estimation for Beamforming and Postfiltering 44
3.3 Integrated DNN-based Parameter Estimation for Multichannel Speech
Enhancement 46
3.3.1 Architecture of the DNNs 48
3.3.2 Postfiltering with Integrated Estimation of PSDs 49
3.4 Experimental and Results 52
3.4.1 Experimental Configurations 52
3.4.2 Experimental Results 53
4 Conclusions 55
References 58
– vii
Fantasizing Chinese/Indonesian Hero: Njoo Cheong Seng and the Gagaklodra Series
No full textFantasizing Chinese/ Indonesian Hero : Njoo Cheong Seng and the gagaklodra Series.
This article examines the popular fantasy series, Gagaklodra, created by Njoo Cheong Seng in the late period of colonial Indonesia. As one of the earliest original works of crime and detective genre in Indonesia, conceived by an exceptionally cosmopolitan author of Chinese heritage, the Gagaklodra series is remarkably hybrid in terms of concept and content. It takes after both indigenous folklore and European cloak-and-dagger stories, anchored by a Javanese-Chinese protagonist. Written over the span of twenty-two years and three political regimes, the episodes of Gagaklodra not only capture the rapidly changing historical landscape between the 1930s and the 1940s, but also communicate a more inclusive outlook with regard to national belonging for the nation that was about to be born.Fantasmer le héros chinois/ indonésien : Njoo Cheong Seng et la série gagaklodra.
Cet article examine la série fantastique populaire intitulée Gagaklodra créée par Njoo Cheong Seng en Indonésie vers la fin de la période coloniale. Figurant parmi les premiers textes originaux du genre policier en Indonésie, conçue par un auteur héritier de culture chinoise exceptionnellement cosmopolite, la série Gagaklodra présente un caractère hybride remarquable en termes de concept et de contenu. Elle emprunte à la fois au folklore autochtone et aux histoires de cape et d’épée européennes, incarnée par un protagoniste javano-chinois. Écrits en l’espace de vingt-deux ans durant lesquels vont se succéder trois régimes politiques, les épisodes de Gagaklodra rendent non seulement compte du changement rapide du paysage politique entre les années 1930 et les années 1940, mais révèlent aussi une perspective plus globale au regard de l’appartenance nationale pour une nation en gestation.Chandra Elizabeth. Fantasizing Chinese/Indonesian Hero: Njoo Cheong Seng and the Gagaklodra Series. In: Archipel, volume 82, 2011. pp. 83-113
Computing many faces in arrangements of lines and segments
No full textWe present randomized algorithms for computing many faces in an arrangement of lines or of segments in the plane, which are considerably simpler and slightly faster than the previously known ones. pn The main new idea is a simple randomized O(n log n) expected time algorithm for computing root n cells in an arrangement of n lines.A part of this work was done while the first and third authors were visiting Charles University and while the first author was visiting Utrecht University. The first author has been supported by National Science Foundation Grant CCR-93-01259 and an NYI aword. The second author has been supported by Charles University grant No. 351 and Czech Republic Grant GACR 201/93/2167. The third author has been supported by the Netherlands' Organization for Scientific Research (NWO) and partially supported by ESPRIT Basic Research Action No. 7141 (project ALCOM 2:Algorithms and Complexity)
Range searching in low-density environments
No full textWe define a set of arbitrarily-shaped objects in R(d) to be a low-density environment if any axis-parallel hypercube intersects only few objects of comparable or larger size. Generalizing and simplifying previous results for fat objects, we present a data structure for point location in a low-density environment, and we show how this data structure can be extended to perform range search queries with query ranges of size comparable to the smallest object.This research was partially supported by ESPRIT Basic Research Action No. 6546 (project PROMotion) and by the Netherlands' Organization for Scientific Research (NWO). The first author also acknowledges partial support by Pohang University of Science and Technology Grant P95015, 1995
Separating and shattering long line segments
No full textA line l is called a separator for a set S of objects in the plane if l avoids all the objects and partitions S into two non-empty subsets, lying on both sides of l. A set L of Lines is said to shatter S if each line of L is a separator for S, and every two objects of S are separated by at least one line of L. We give a simple randomized algorithm to construct the set of ail separators for a given set S of n line segments in expected time O(n log n), provided the ratio between the diameter of S and the length of the shortest line segment is bounded by a constant. We also give a randomized algorithm to determine a set of lines shattering S, whose expected running time is O(n log n), improving (for this setting) the (deterministic) O(n(2) log n) time algorithm of Freimer, Mitchell and Piatko. (C) 1997 Published by Elsevier Science B.V.Work on paper by the second author has been supported by the Netherlands' Organization for Scientific Research (NWO), by Pohang University of Science and Technology Grant 96F004, 1996, and partially by the nondirected research fund of the Korean Ministry of Education
Dan bai C ji yin (PROC) yu er tong xiao chuan de yi chuan guan xi he gong neng
No full textChan, Wa Cheong.Thesis Ph.D. Chinese University of Hong Kong 2014.Includes bibliographical references (leaves 209-225).Abstracts also in Chinese; appendix I in Chinese.Title from PDF title page (viewed on 07, November, 2016).Chan, Wa Cheong
CUHK electronic theses & dissertations collection
No full textCheong, Hio Teng.Thesis M.Phil. Chinese University of Hong Kong 2015.Includes bibliographical references (leaves 127-139).Abstracts also in Chinese.Title from PDF title page (viewed on 16, November, 2016)
Assessing User Attitudes Toward Mobile Commerce In The U.S. Vs. Korea: Implications For M-Commerce CRM
No full textMobile Commerce (m-commerce) relies on “customer or user interactions” via a mobile device and telecommunications infrastructure for the purpose of interacting, advertising, promoting, and selling products and services. The author of this study explored user attitudes and behavior toward m-commerce in the U.S. vs. Korea. In this paper, the author investigated comparison analysis for the U.S. vs. Korea for the following issues: 1) the factors affecting user attitudes toward mobile phone business; 2) how those factors affect perceived ease of use (EOU) and usefulness (U); 3) the effects of perceived ease of use (EOU) and usefulness (U) on overall attitudes toward the mobile phone business; and 4) how overall attitudes toward mobile phone business affect user/customer satisfaction. Surveys were conducted in two countries and the results reveal the different aspects affecting mobile phone usage in the U.S. vs. Korea. This study also found that user attitudes toward the mobile phone business significantly impact the level of m-satisfaction. Furthermore, this study provides managerial implications and offers suggestions to m-businesses.1
Report on industrial attachment with Jurong Consultants Pte Ltd
No full textThis Industrial Attachment Report serves to provide a concise and vivid account of the exposure the author gained during the 22-week Industrial Attachment at JURONG Consultants Pte Ltd,Marine and Infrastructure department. The author's job scope focused primarily on the planning and design aspects of engineering work. The work nature was highly relevant to her field of study in Civil and Environmental Engineering as it ranges from structural design in the civil engineering aspects to bioswale design and feasibility studies of water sustainability in the environmental engineering aspects. During the attachment, the author gained valuable knowledge through active participation and inquisitive learning. She learnt to build to good rapport with her colleagues and trained herself to communicate confidently with authorities and contractors. In conclusion, this Industrial Attachment had highly supplemented the author's insights in the engineering world. It was undoubtedly a beneficial and educating experience for the author
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