191,243 research outputs found
Bawool Yoo
No full text학위논문(석사)--아주대학교 일반대학원 :분자과학기술학과,2015. 2Ι. Introduction 1
II. Experiments 6
II.1 Chemical Structure 6
II.2 Synthesis 8
II.2.1 Materials 8
II.2.2 Scheme of HMQ-VBS Synthesis 8
II.2.3 Scheme of OHQ-VBS Synthesis 9
II.3 General Characterization 10
II.3.1 1H NMR Analysis 10
II.3.1.1 1H NMR Analysis of intermediates 10
II.3.1.2 1H NMR Analysis of HMQ-VBS and OHQ-VBS 11
III. Results and Discussion 15
III.1 Design and Synthesis 15
III.2 Thermal Analysis 17
III.3 Second Harmonic Generation (SHG) Test 20
III.4 Crystal Growth and Structure 22
IV. Conclusions 34
V. References 35MasterDerivatives of highly nonlinear optical ionic salt organic crystal HMQ-T (2-(4-hydroxy-3-methoxystyryl)-1-methylquinolinium 4-methylbenzenesulfonate) with 2-(4-hydroxy-3-methoxystyryl)-1-methylquinolinium 4-vinylbenzenesulfonate (HMQ-VBS) replacing the 4-methylbenzenesulfonate of HMQ-T have been synthesized and characterized. In addition we synthesized and characterized derivatives of another highly nonlinear optical ionic salt organic crystal OHQ-T (2-(4-hydroxystyryl)-1-methylquinolinium 4-methylbenzenesulfonate) with 2-(4-hydroxystyryl)-1-methylquinolinium 4-vinylbenzenesulfonate (OHQ-VBS) replacing same counteranion. OHQ-VBS crystal exhibits a highly macroscopic nonlinear optical properties with highly second harmonic generation (SHG) efficiency. The cations of OHQ-VBS constitutes strong head-to-tail hydrogen bonds, and they exhibits acentric crystal structure of cations and counteranion layers. Therefore HMQ-VBS crystal exhibits a centrosymmetric crystal structure. X-ray crystallographic analysis revealed that the crystal structure of OHQ-VBS is monoclinic Pn, which is similar to that of OHQ-T, however HMQ-VBS exhibits a centrosymmetric P21/c structure compare to other three molecules
Campbellospira Yoo 1994, n.gen.
No full textCampbellospira n.gen. Type species. CampbeUospira conica n.sp. Definition. Turbiniform, low-spired, conical shell; moderately phaneromphalous; ornamented by transverse cords and spiral lirae, most prominent near upper suture; selenizone concave between a pair of conspicuous cords just above periphery. Geological age. Middle Tournaisian. Etymology. This genus is named for Professor K.S.W. Campbell of the Australian National University for his contribution to the study of eastern Australian Carboniferous geology and palaeontology. Remarks. This genus is similar to other pleurotomarioideans in general, but is different in having a planktotrophic protoconch. Specimens belonging to this genus are very common at the type locality. [table omitted] Australian Carboniferous species. Campbellospira conica n.sp., Campbellospira sp. A, Band C, all from Swains Gully.Published as part of Yoo, E. K., 1994, Early Carboniferous Gastropoda from the Tamworth Belt, New South Wales, Australia, pp. 63-120 in Records of the Australian Museum 46 (1) on pages 76-77, DOI: 10.3853/j.0067-1975.46.1994.18, http://zenodo.org/record/465459
A form driven object-oriented reverse engineering methodology
No full textLegacy applications are valuable assets that should be integrated into business systems in succeeding generations. In order to take advantage of these applications, progressive companies seek to improve current operations by reverse engineering. This paper proposes the form driven object-oriented reverse engineering (FORE) methodology by using forms to recover semantics of legacy applications. Forms are exceptionally easy to understand because of the user-oriented nature of the contents of business. This form driven object-oriented reverse engineering methodology consists of five different phases: form usage analysis, form object slicing, object structure modeling, scenario design, and model integration. Knowledge of the form structure and the user's interaction between legacy application is compiled to extract the design semantics. This application demonstrates the practical usability of the FORE methodology by transforming the resulting object models into well-known UML-based models. (C) 2000 Published by Elsevier Science Ltd. All rights reserved
A scenario-based object-oriented hypermedia design methodology
No full textThis paper defines an object-oriented methodology for developing hypermedia information systems. The methodology consists of six phases: domain analysis; object modeling; view design;navigation design; implementation design; and construction. Users' requirements are analyzed with a responsibility-driven technology using scenarios. Object-oriented views are generated as the result of object modeling, and then used for the subsequent navigation and implementation design. The implementation design phase deals with database schema, page structure and flow, and user interface. This methodology integrates enterprise databases with distributed hypermedia systems via Internet, Intranet, or Electronic Commerce. (C) 1999 Elsevier Science B.V. All rights reserved
Microstructure evolution of HP40-Nb alloys during aging under air at 1000 °C
Get PDFTwo as-cast HP 40 alloys provided by different manufacturers were aged at 1000 °C under laboratory air. They had the same as-cast microstructure consisting of austenite dendrites delineated by a network of eutectic Nb-rich MC and Cr-rich M7C3 carbides. After aging for several months, they showed similar microstructures in the bulk materials, though M7C3 carbides have been replaced by M23C6 carbides. As expected, a sub-surface zone depleted in chromium has appeared where a tetragonal CrNbC could be identified in both materials. However, the composition of the transition zones between the surface and the bulk materials differed, mainly because one of the materials underwent significant nitrogen pick-up with associated precipitation of M6(C,N) and M2(C,N) phases. On the contrary, the other alloy did show only one intermediate zone with a mix of CrNbC, M23C6 and MC carbides. A full account of the microstructures observed in the aged materials is given
The New Sovereignty and the Old Constitution: The Chemical Weapons Convention and the Appointments Clause.
Get PDFYoo, John C.. (1998). The New Sovereignty and the Old Constitution: The Chemical Weapons Convention and the Appointments Clause.. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/167640
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
An Object Oriented Simulation for Determining the Number of AGV's in Computer Integrated Manufacturing
No full textA 40fJ/c-s 1 V 10 bit SAR ADC with Dual Sampling Capacitive DAC Topology
No full textA 40 fJ/c-s, 1 V, 10-bit SAR ADC is presented for energy constrained wearable body sensor network application. The proposed 10-bit dual sampling capacitive DAC topology reduces switching energy by 62% compared with 10-bit conventional SAR ADC. Also, it is more robust to capacitor mismatch than the conventional architecture due to its cancelling effect of each capacitive DAC. The proposed SAR ADC is fabricated in 0.18 mu m 1P6M CMOS technology and occupies 1.17 mm(2) including pads. It dissipates only 1.1 mu W with 1 V supply voltage while operating at 100 kS/s.N
A fully digital polar transmitter using a digital-to-time converter for high data rate system
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