Using SG Arrays for Hydrology in Comparison with GRACE Satellite Data, with Extension to Seismic and Volcanic Hazards

Crossley David,Hinderer Jacques The Korean Society of Remote Sensing 2005 大韓遠隔探査學會誌 Vol.21 No.1

We first review some history of the Global Geodynamics Project (GGP), particularly in the progress of ground-satellite gravity comparisons. The GGP Satellite Project has involved the measurement of ground-based superconducting gravimeters (SGs) in Europe for several years and we make quantitative comparisons with the latest satellite GRACE data and hydrological models. The primary goal is to recover information about seasonal hydrology cycles, and we find a good correlation at the microgal level between the data and modeling. One interesting feature of the data is low soil moisture resulting from the European heat wave in 2003. An issue with the ground-based stations is the possibility of mass variations in the soil above a station, and particularly for underground stations these have to be modeled precisely. Based on this work with a regional array, we estimate the effectiveness of future SG arrays to measure co-seismic deformation and silent-slip events. Finally we consider gravity surveys in volcanic areas, and predict the accuracy in modeling subsurface density variations over time periods from months to years.

Using SG Arrays for Hydrology in Comparison with GRACE Satellite Data, with Extension to Seismic and Volcanic Hazards

David Crossley,Jacques Hinderer 大韓遠隔探査學會 2005 大韓遠隔探査學會誌 Vol.21 No.1

We first review some history of the Global Geodynamics Project (GGP), particularly in the progress of ground-satellite gravity comparisons. The GGP Satellite Project has involved the measurement of ground-based superconducting gravimeters (SGs) in Europe for several years and we make quantitative comparisons with the latest satellite GRACE data and hydrological models. The primary goal is to recover information about seasonal hydrology cycles, and we find a good correlation at the microgal level between the data and modeling. One interesting feature of the data is low soil moisture resulting from the European heat wave in 2003. An issue with the ground-based stations is the possibility of mass variations in the soil above a station, and particularly for underground stations these have to be modeled precisely. Based on this work with a regional array, we estimate the effectiveness of future SG arrays to measure co-seismic deformation and silent-slip events. Finally we consider gravity surveys in volcanic areas, and predict the accuracy in modeling subsurface density variations over time periods from months to years.

Identifying Linguistic Cues that Distinguish Text Types : A Comparison of First and Second Language Speakers

Scott A. Crossley,Max M. Louwerse,Danielle S. McNamara 서울대학교 언어교육원 (구 서울대학교 어학연구소) 2008 語學硏究 Vol.44 No.2

The authors examine the degree to which first (L1) and second language (L2) speakers of English are able to distinguish between simplified or authentic reading texts from L2 instructional books and whether L1 and L2 speakers differ in their ability to process linguistic cues related to this distinction. These human judgments are also compared to computational judgments which are based on indices inspired by cognitive theories of reading processing. Results demonstrate that both L1 and L2 speakers of English are able to identify linguistic cues within both text types, but only L1 speakers are able to successfully distinguish between simplified and authentic texts. In addition, the performance of a computational tool was comparable to that of human performance. These findings have important implications for second language text processing and readability as well as implications for material development for second language instruction.

Bohai/Parhae Identity and the Coherence of Dan gur under the Kitan/Liao Empire

Pamela Kyle Crossley(파멜라 카일 크로슬리) 고려대학교 한국사연구소 2016 International Journal of Korean History Vol.21 No.1

요사(遼史)는 926년 요제국이 발해를 멸망시켰으며, 이후 발해민들을 노예상태로 전락시키고, 제국에 재정착시켰다고 기록한다. 근대 고고학은 거란어로 쓰여진 금석학적 자료와 함께 이러한 전개의 몇 부분을 확인했지만, 보다 복잡한 이야기를 제시한다. 아이신 기오로 울라희춘(愛新覺羅 烏拉熙春), 요시모토 미치마사(吉本道雅), 임상선, 사와모토 미츠히로, 그리고 왕샹준은 926년의 요제국의 발해 침략을 둘러싼 정치적 환경과 그 거주민들의 지위를 조명했다. 대부분의 발해민들은 발해 귀족, 군인, 그리고 고위관료들이 지역행정부에서 확고한 역할을 유지하고 있던 그들의 전통적인 영역에 남아있었다. 이 논문은 요제국 행정부 활동, 즉 다가문과 같은 발해의 귀족, 그리고 고모한(高謨翰)과 같은 지식인 계층에 대한 발해의 영향력과 발해 인구변동의 예측치에 주목한다. 이를 통해 기존 대표적인 문헌자료에서 제시되었던 것 보다 중요하다고 할 수 있는 북동지방 정치전통의 전환에 미친 발해의 역할을 제시하고자 한다. 발해민들은 요제국이 침략하여 그들을 외지고 열악한 환경으로 좌초시킨 이후 정체성과 사회적 구조가 파괴된 불행한 존재였다기 보다는, 실제적인 하나의 정치적 연속성이며, 여진족, 궁극적으로는 만주라는 그들의 계승자에 대한 중대한 영향을 미쳤다는 것이다. The Liao shi [Liaoshi] (遼史) suggests that in 926 the Liao empire destroyed the state of Bohai, and afterward forced the Bohai people into servitude and resettlement across the empire. Modern archaeology together with epigraphical sources in the Kitan language confirm some of this narrative, but suggest a far more complicated story. Researches by scholars such as Aisingioro Ulhicun, Yoshimoto Michimasa, Im Sangsŏn, Sawamoto Mitsuhiro and Wang Shanjun have shed new light on the political circumstances of the Liao invasion of Bohai in 926 and the subsequent status of its inhabitants. A majority of the Bohai population remained in their traditional territories, where Bohai aristocrats, soldiers and high-ranking officials retained distinct roles in local administration. This essay looks at Bohai influence upon Liao administrative practices, the status of Bohai aristocrats of the Da lineage and elites such as Gao Mohan, and the probable outlines of Bohai demography to suggest that the Bohai role in transmission of Northeastern political traditions, in particular, may have been much more important than would be suggested on the basis of standard literary resources. Instead of being a doomed people whose identities and social structures evaporated after Liao resettlement policies stranded them in remote and inhospitable surroundings, the Bohai story may actually be one of political continuity and a seminal influence upon their successors, the Jurchens and ultimately the Manchus.

Design and Development of Superimposed Directional Comparison Protection Scheme

Guo Ziye,Crossley Peter A.,Li Haiyu 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.4

To achieve the UK Net Zero future by 2050, National Grid needs to integrate significantly more renewable generation into the power grid. This increases the level of harmonics, reduces system inertia and adversely affects the fault level and the performance of existing protection relays. One solution to the protection problem is the use of new types of protection that use the change in the voltage and current caused by the fault, often referred to as a superimposed or incremental based protection technique. This paper describes how a superimposed directional comparison protection scheme performed when applied to a reduced section of the full UK National Grid network and relates this to the operating performance of traditional protection. Tests are performed using the simulators DIgSILENT and RelaySimTest configured with different source levels, fault types, fault locations and fault resistances. Results show the superimposed based protection scheme achieves faster fault detection and tripping than conventional protection and is capable of detecting higher resistive faults on networks where the source capacities vary from strong to weak.

Predicting Second Language Writing Proficiency in Learner Texts Using Computational Tools

정연주,Scott Crossley,Danielle McNamara 아시아테플 2019 The Journal of Asia TEFL Vol.16 No.1

This study explores whether linguistic features can predict second language writing proficiency in the Michigan English Language Assessment Battery (MELAB) writing tasks. Advanced computational tools were used to automatically assess linguistic features related to lexical sophistication, syntactic complexity, cohesion, and text structure of writing samples graded by expert raters. The findings of this study show that an analysis of linguistic features can be used to significantly predict human judgments of the essays for the MELAB writing tasks. Furthermore, the findings indicate the relative contribution of a range of linguistic features in MELAB essays to overall second language (L2) writing proficiency scores. For instance, linguistic features associated with text length and lexical sophistication were found to be more predictive of writing quality in MELAB than those associated with cohesion and syntactic complexity. This study has important implications for defining writing proficiency at different levels of achievement in L2 academic writing as well as improving the current MELAB rating scale and rater training practices. Directions for future research are also discussed.

Islanding Detection for Distributed Generation

Ding, X.,Crossley, P.A.,Morrow, D.J. The Korean Institute of Electrical Engineers 2007 Journal of Electrical Engineering & Technology Vol.2 No.1

The paper discussed various techniques for islanding detection and described in detail the working principles of ROCOF and vector shift relays. A simulator was used to investigate why the stability of both types of relays maybe affected by network and load switching, short-circuit faults and in the case of a ROCOF relay the loss of bulk generation or the tripping of a transmission feeder. Finally, to enhance the reliability of Loss of Mains protection, a new islanding detection technique based on a GPS synchronized phasor measurement system was proposed.

Islanding Detection for Distributed Generation

X. Ding,P. A. Crossley,D. J. Morrow 대한전기학회 2007 Journal of Electrical Engineering & Technology Vol.2 No.1

The paper discussed various techniques for islanding detection and described in detail theworking principles of ROCOF and vector shift relays. A simulator was used to investigate why the stability of both types of relays maybe affected by network and load switching, short-circuit faults and in the case of a ROCOF relay the loss of bulk geneFinally, to enhance the reliability of Loss of Mains protection, a new islanding detection technique based on a GPS synchronized phasor measurement system was proposed.

An Efficient Fluorescence Sensor for Superoxide with an Acridinium Ion-Linked Porphyrin Triad

Kotani, Hiroaki,Ohkubo, Kei,Crossley, Maxwell J.,Fukuzumi, Shunichi American Chemical Society 2011 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.133 No.29

<P>Addition of potassium superoxide with 18-crown-6 ether (KO<SUB>2</SUB><SUP>•–</SUP>–18-crown-6) to a toluene solution of an acridinium ion-linked porphyrin triad (Acr<SUP>+</SUP>–H<SUB>2</SUB>P–Acr<SUP>+</SUP>) resulted in a remarkable enhancement of the fluorescence intensity. Thus, Acr<SUP>+</SUP>–H<SUB>2</SUB>P–Acr<SUP>+</SUP> acts as an efficient fluorescence sensor for superoxide. Electron transfer from KO<SUB>2</SUB><SUP>•–</SUP>–18-crown-6 to the Acr<SUP>+</SUP> moiety to produce the two-electron-reduced species (Acr<SUP>•</SUP>–H<SUB>2</SUB>P–Acr<SUP>•</SUP>) results in inhibition of the fluorescence quenching via photoinduced electron transfer, as revealed by laser flash photolysis measurements.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2011/jacsat.2011.133.issue-29/ja204161j/production/images/medium/ja-2011-04161j_0003.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja204161j'>ACS Electronic Supporting Info</A></P>

Islanding Detection for Distributed Generation

Xiaolin Ding,Peter.A.Crossley,D.John.Morrow 대한전기학회 2007 Journal of Electrical Engineering & Technology Vol.2 No.1

The paper discussed various techniques for islanding detection and described in detail the working principles of ROCOF and vector shift relays. A simulator was used to investigate why the stability of both types of relays maybe affected by network and load switching, short-circuit faults and in the case of a ROCOF relay the loss of bulk generation or the tripping of a transmission feeder. Finally, to enhance the reliability of Loss of Mains protection, a new islanding detection technique based on a GPS synchronized phasor measurement system was proposed.