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- Type:
- Article
- Description/Abstract:
- This study deals with the development and application of an active control law for the vibration suppression of beam-like flexible structures experiencing transient disturbances. Collocated pairs of sensors/actuators provide active control of the structure. A design methodology for the closed-loop control algorithm based on fuzzy logic is proposed. First, the behavior of the open-loop system is observed. Then, the number and locations of collocated actuator/sensor pairs are selected. The proposed control law, which is based on the principles of passivity, commands the actuator to emulate the behavior of a dynamic vibration absorber. The absorber is tuned to a targeted frequency, whereas the damping coefficient of the dashpot is varied in a closed loop using a fuzzy logic based algorithm. This approach not only ensures inherent stability associated with passive absorbers, but also circumvents the phenomenon of modal spillover. The developed controller is applied to the AFWAL/FIB 10 bar truss. Simulated results using MATLAB© show that the closed-loop system exhibits fairly quick settling times and desirable performance, as well as robustness characteristics. To demonstrate the robustness of the control system to changes in the temporal dynamics of the flexible structure, the transient response to a considerably perturbed plant is simulated. The modal frequencies of the 10 bar truss were raised as well as lowered substantially, thereby significantly perturbing the natural frequencies of vibration. For these cases, too, the developed control law provides adequate settling times and rates of vibrational energy dissipation.
- Creator/Author:
- Weller, Tanchum; Cohen, Kelly, and Ben-Asher, Joseph Z.
- Submitter:
- Kelly Cohen
- Date Uploaded:
- 02/08/2017
- Date Modified:
- 04/05/2017
- Date Created:
- 2002-06
- License:
- All rights reserved
- Type:
- Article
- Description/Abstract:
- The present study deals with an AFCA (Adaptive Fuzzy Control Algorithm) for an Euler-Bemoulli approximation of a two-dimensional version of a cantilever beam-like orthogonal tetrahedral space truss. Transient disturbances, modeled as a unit impulse, excite all the modes of the beam. The resulting transverse displacement at the free end of the beam and its corresponding rate are observed by sensors placed there, and active control of the beam is provided by a collocated force actuator. A design methodology, based on fuzzy logic which assumes no a priori knowledge of plant dynamics, for the closed-loop control algorithm results in relatively quick settling times, low overshoots and dying out of vibration within a few seconds. The control algorithm is enhanced and made much faster by eliminating the need of repeatedly solving the set of differential equations of motion of an emulated dynamic vibration absorber. When the control force is turned off after a mere 15 seconds, almost all the vibrational energy is dissipated as the beam returns to its undisturbed state throughout its length. In addition, the performance of the AFCA is insensitive to varying initial conditions. To examine the robustness of the control system to changes in the temporal dynamics of the cantilever beam, the transient disturbance response to a considerably perturbed plant is simulated. The Young's modulus of the beam was raised as well as lowered by 60%, substantially perturbing the natural frequencies of vibration compared to the nominal plant. The AFCA provided similar settling times and rates of vibrational energy dissipation, satisfying the aim of plant model independence.
- Creator/Author:
- Abramovich, Haim; Weller, Tanchum; Cohen, Kelly, and Levitas, Joseph
- Submitter:
- Kelly Cohen
- Date Uploaded:
- 02/08/2017
- Date Modified:
- 04/05/2017
- Date Created:
- 1996-03
- License:
- All rights reserved
- Type:
- Article
- Description/Abstract:
- OBJECTIVE: Damage to hair from UV exposure has been well reported in the literature and is known to be a highly complex process involving initiation via absorption of UV light followed by formation and propagation of reactive oxygen species (ROS). The objective of this work was to understand these mechanisms, explain the role of copper in accelerating the formation of ROS and identify strategies to reduce the hair damage caused by these reactive species. METHODS: The location of copper in hair was measured by Transmission electron microscopy–(TEM) X-ray energy dispersive spectroscopy (XEDS) and levels measured by ICP-OES. Protein changes were measured as total protein loss via the Lowry assay, and MALDI ToF was used to identify the biomarker protein fragments. TBARS assay was used to measure lipid peroxide formation. Sensory methods and dry combing friction were used to measure hair damage due to copper and UV exposure and to demonstrate the efficacy of N,N’ ethylenediamine disuccinic acid (EDDS) and histidine chelants to reduce this damage. RESULTS: In this work, a biomarker protein fragment formed during UV exposure is identified using mass spectrometry. This fragment originates from the calcium-binding protein S100A3. Also shown is the accelerated formation of this peptide fragment in hair containing low levels of copper absorbed from hair during washing with tap water containing copper ions. Transmission electron microscopy (TEM) X-ray energy dispersive spectroscopy (XEDS) studies indicate copper is located in the sulphur-poor endo-cuticle region, a region where the S100A3 protein is concentrated. A mechanism for formation of this peptide fragment is proposed in addition to the possible role of lipids in UV oxidation. A shampoo and conditioner containing chelants (EDDS in shampoo and histidine in conditioner) is shown to reduce copper uptake from tap water and reduce protein loss and formation of S100A3 protein fragment. In addition, the long-term consequences of UV oxidation and additional damage induced by copper are illustrated in a fourmonth wear study where hair was treated with a consumer relevant protocol of hair colouring treatments, UV exposure and regular shampoo and conditioning. CONCLUSIONS: The role of copper in accelerating UV damage to hair has been demonstrated as well as the ability of chelants such as EDDS and histidine in shampoo and conditioner products to reduce this damage.
- Creator/Author:
- McComb, D. W.; Marsh, J. M.; Sun, Y.; Chaudhary, T.; Flagler, M. J.; Coderch, L.; Mamak, M.; Greis, Kenneth D.; Rubio, L.; Williams, R. E. A., and Davis, M. G.
- Submitter:
- Kenneth Greis
- Date Uploaded:
- 03/03/2017
- Date Modified:
- 04/07/2017
- Date Created:
- 2015-04
- License:
- All rights reserved
- Type:
- Article
- Description/Abstract:
- As I have previously shown, Alexandre Brongniart established a coherent science of ceramics. By the mid-nineteenth century, Brongniart had popularised the term "la céramique" as a widely-applicable name for the field of pottery and porcelain making, and other related arts. In the Twentieth Century, ceramic manufacturing became increasingly technical. The inclusive field of artisans and industrialists that Brongniart had once envisioned was fracturing. Voices called for the separation of pottery making from experimental, industrial ceramics and the meaning of the term “ceramics” was hotly debated. Numerous etymologies were traced, but, as the predominant language of science transferred from French to English, none of the twentieth-century authors recognized Brongniart’s key role in the invention of the term. Critically, this language debate coincided with and reflected the global politics, nationalism, and warfare of the first half of the Twentieth Century.
- Creator/Author:
- Carr-Trebelhorn, Julia
- Submitter:
- Julia Carr-Trebelhorn
- Date Uploaded:
- 03/09/2026
- Date Modified:
- 03/09/2026
- Date Created:
- 2026-03-09
- License:
- Attribution-NonCommercial-NoDerivs 4.0 International
- Type:
- Article
- Description/Abstract:
- Taking on the task of ordering the sciences related to pottery and clay-based objects, natural historian and porcelainier Alexandre Brongniart sought a new way of describing the ancient practice. Early in his forty-seven-year career as director of the Sèvres Porcelain Manufactory, Brongniart developed a research center for the advanced study of pottery and porcelain making. Brongniart recognized that an inclusive and distinct term for the field was necessary, but it had to be introduced carefully, so that it was welcomed rather than rejected as presumptuous. Through close reading of Brongniart’s writings, as well as contemporary periodicals and the texts of other authors, the development of the word “ceramic” – originally introduced by Brongniart and his associates in French as “la céramique” – can be traced closely. I show that this was a deliberate, methodical, and years-long effort to create a durable, comprehensive term.
- Creator/Author:
- Carr-Trebelhorn, Julia
- Submitter:
- Julia Carr-Trebelhorn
- Date Uploaded:
- 03/09/2026
- Date Modified:
- 03/09/2026
- Date Created:
- 2026-03-09
- License:
- Attribution-NonCommercial-NoDerivs 4.0 International
- Type:
- Article
- Description/Abstract:
- Interactive product prototyping has been widely taught in industrial design studio courses to prepare design students in dealing with dynamic interactions of using digital products. While it requires the integration of design and technology, the lack of systematic approaches of the studio curricula creates a great challenge for students who are not familiar with technology in creating interactive prototypes successfully. A theoretical framework is developed from the human-machine interaction model and the sequential flow of task analysis methods. Based on this framework, a human-machine interaction (HMI) flow diagram is proposed with which interaction elements, relationships, and flows are specified and categorized. The flow diagram is utilized to create a storyboard and an allocation flowchart subsequently. A structured design process based on these methods was applied to an interactive product design studio course in an undergraduate industrial design program. Students created working prototypes of interactive products, following the structured design process consisting of an HMI flow diagram, a storyboard, and an allocation flowchart. 104 students (87.4%) among 119 succeeded in translating their ideas to functioning circuits. 74 students (62.2%) successfully integrated electronics components into working physical prototypes while 30 students (25.2%) just made the circuits work. The structured design process makes a transition from initial ideation to programming smooth and incremental. This helps students without previous programming experience to understand the logic flow and to develop algorithms. The HMI flow diagram is useful for analysis, concept development, and the specification of interactions, and helps students to grasp the effect of interactive features on user experience.
- Creator/Author:
- Ghim, Yong-Gyun
- Submitter:
- Yong-Gyun Ghim
- Date Uploaded:
- 12/05/2021
- Date Modified:
- 12/05/2021
- License:
- Attribution-NonCommercial 4.0 International
- Type:
- Article
- Description/Abstract:
- The purpose of this study is to plan and operate design-workshops based on project-based learning (PBL), and examine their educational value for students. The PBL workshop encour- ages direct participation from students and produces educational value, and it is important to raise the interest level of workshops to elicit proactive participation. The workshop in this study was carried out over two weeks in January 2017 at Korea’s Yonsei University. The workshop was composed of eight teams of students from three countries, including Korea, China, and Japan, and the course was primarily divided into two sessions. The workshop participants examined in this thesis were notably satised with the elements of the course meant to garner interest. In the questionnaire results, participants also indicated that they obtained ample educational value through the workshop. An important element of the workshop was to connect the participants with businesses, which is also an important component of design education. Despite this, participants expressed a relatively lower level of satisfaction com- pared to other elements of the workshop. The results and analysis of this study will hopefully become a meaningful resource for educators when designing workshops in the future.
- Creator/Author:
- Chang, Ikjoon and Hwang, Suhong
- Submitter:
- Lora Alberto
- Date Uploaded:
- 11/17/2017
- Date Modified:
- 02/08/2018
- Date Created:
- 2017-10-31
- License:
- Attribution-NonCommercial 4.0 International
- Type:
- Article
- Description/Abstract:
- Background: Role of apolipoprotein (apo) A-II on metabolism of high density lipoproteins (HDLs) is unknown. Results: Conformational changes of apoA-I, the major apolipoprotein of HDL, caused by apoA-II in discoidal HDL are confined to two regions of apoA-I. Conclusion: Interactions between the two major apolipoproteins in discoidal HDL are site specific. Significance: Functional implications of HDL complexes will significantly benefit from such structural information.
- Creator/Author:
- Gauthamadasa, Kekulawalage; Vaitinadin, Nataraja Sarma; Homan, Reyn; Macha, Stephen; Dresman, James L.; D. Silva, R. A. Gangani, and Greis, Kenneth D.
- Submitter:
- Kenneth Greis
- Date Uploaded:
- 03/01/2017
- Date Modified:
- 04/07/2017
- Date Created:
- 2012-03
- License:
- All rights reserved
- Type:
- Article
- Description/Abstract:
- Signature-based intrusion detection methods report high accuracy with a low false alarm rate. However, they do not perform well when faced with new or emerging threats. This work focuses on anomaly-based data driven methods to identify potential zero-day-attacks using a specific class of neural networks known as the autoencoder.
- Creator/Author:
- Li, Chengcheng; Lee, Kijung; Mathur, Nitin, and Gonen, Bilal
- Submitter:
- Jess Kropczynski
- Date Uploaded:
- 05/15/2020
- Date Modified:
- 05/15/2020
- Date Created:
- 2020-04-14
- License:
- All rights reserved
- Type:
- Article
- Description/Abstract:
- This archeometric study analyzed local clay deposits at the Ingels Family Farm, settled in the Early Nineteenth Century in Bourbon County Kentucky. The redware pottery made on site was bartered and sold in the region, and the clay deposits were also used to make the bricks that constructed the 1820 Ingels family residence, still extant as of May 2026. Numerous materials characterization techniques including XRD, XRF, DTA/TGA, Spectroscopy, wet chemical analysis, and SEM were used to determine the characteristics of the local clay deposit and the identifying characteristics of the redware. The study also tested the wares to determine an approximate firing range, which was consistent with the requirements of low-to-mid fired earthenware. This study was done using archaeological materials from a previous archaeological investigation of the farm, but new material was added with the assistance the USDA Soil Survey Office in Kentucky, who drilled core samples for the project in Spring 2012.
- Creator/Author:
- Carr-Trebelhorn, Julia; O'Malley, Nancy, Assistant Director, University of KY Museum of Anthropology, and Eitel, Richard, University of KY Department of Materials Science
- Submitter:
- Julia Carr-Trebelhorn
- Date Uploaded:
- 05/30/2026
- Date Modified:
- 05/30/2026
- Date Created:
- 2013-05-01
- License:
- Attribution-NonCommercial-NoDerivs 4.0 International