255 research outputs found
Contact-type mechanical interfaces for high speed digital interconnects
No full textThesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1999.Includes bibliographical references (p. 96).The objective of this work was to determine the feasibility of Ball Grid Array (BGA) planarization and to investigate the effects of mechanical contacts on signal integrity for highspeed digital signals. As devices become smaller and clock frequencies increase, new technologies for contacting devices are being developed, especially in the field of semiconductor test. These contactors will be incorporated into a socket or an interconnect used in testing devices or printed circuit boards. The heights of the solder ball leads on BGA packages have a high degree of co-planarity. As BGA pitches become tighter, the requirement for improved co-planarity persists. This thesis shows that through diamond turning techniques, the co-planarity of the solder ball leads can be improved. Planarization of solder balls enables the use and development of rigid interconnects. Interconnections generally have a built in compliance to them to accommodate for co-planarity. Reducing co-planarity eliminates the need for compliant interconnects. Contact mechanics identifies the conical shaped tip as the optimal tip shape, providing the best mechanical connection. The intent of the tip shape investigation is to correlate indentation theory with signal integrity. The electrical performance of the contactor tip is evaluated using the industry standard pogo pin. Mechanical parameters are varied to observe the effect on the signal integrity. At high frequencies, the interconnect provides a vulnerable location for signal losses to occur. A new interconnect design to address the electrical performance of existing designs is introduced. The cantilevered interconnect consists of a coplanar waveguide cross-section. The interconnect is both mechanically and electrically sound. This thesis presents aspects of mechanical contact interfaces for electrical signal testing purposes. It focuses on device interfacing, contactor tip shape, signal integrity and new interconnect designs.by Asha Balakrishnan.S.M
Waaya-aragnimadeydii 15ka Sano iyo Siyaasadda Puntland 1998-2012
No full textQoraaga, oo ah Caasha Geelle, waxay buuggan kaga hadlaysaa waaya-aragnimadeeda 15 sano iyo siyaasadda Puntaland, iyo weliba la soo shaqayneedii ururrada rayidka ah.La scrittrice, Asha Gelle, descrive in questo suo libro i suoi 15 anni di esperienza politica nel governo locale del Puntland (Somalia), soprattutto la sua collaborazione con le organizzazioni di servizio sociale.The author, Asha Gelle, describes her 15 years of political experience in the local government of Puntland (Somalia), especiallu her cooperation with social service organizations
Development of novel dynamic indentation techniques for soft tissue applications
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (leaves 141-149).Realistic material models to simulate the behavior of brain tissue at large deformations and high strain rates are necessary when designing equipment to protect against ballistic impacts. Acquiring experimental data for brain tissue response is critical to developing appropriate models. Current in vivo and in situ procedures for testing the material behavior of soft tissues are dominated by indentation techniques. The major challenge for this testing configuration is in finding a unique solution to the "inverse problem" i.e., obtaining material properties that are uniquely defined by the indentation force-displacement response. Much of the information related to the interplay between shear and bulk compliance in the deformation field beneath the indenter is lost when capturing the single force-displacement output. To address this challenge, we propose a material testing technique that follows the well- proven path of conventional indentation methods, but also enriches the signal by acquiring displacement data for an offset, passive surface tracking sensor. We present the results of a finite element (FE) study to demonstrate that the addition of a secondary sensor can help to discern between materials with varying degrees of compressibility. To this end, a large displacement in vivo dynamic indentation surface tracking (DIST) tool was designed and manufactured. This tool incorporates the secondary sensor concept to measure the force-displacement response of brain tissue at strain rates up to 1000%/s. The technique is applied in vitro to measure the response of porcine brain tissue. To select an appropriate constitutive framework for porcine brain tissue in vitro, uniaxial compression tests measuring the corresponding lateral stretch response are performed.(cont.) A three-dimensional large deformation constitutive model for brain tissue is developed. The model accounts for the observed features of the material response including non-linearity, conditioning, hysteresis, and strain-rate dependence. The model is incorporated into an FE simulation of the brain indentation tests performed with the DIST tool. The effectiveness of the DIST as a material-testing tool is assessed.by Asha Balakrishnan.Ph.D
IDENTITY CRISIS IN ADOLESCENCE PERIOD EXPERIENCED BY ASHA IN SHILPI SOMAYA GOWDA’S SECRET DAUGHTER
No full textThis research aims to identify the identity statuses which mark the identity crisisof the main character in Gowda’s Secret Daughter, Asha, an Asian-Indian adolescent who lives in America with her adoptive mixed-race parents, to find out the impact of Asha’s identity crisis towards her sixth stage of psychosocial development, and to identify how the psychosocial issue is reflected in the novel. To answer the objectives, this research employed Erikson’s fifth and sixth psychosocial development stages theory, Marcia’s identity achievement status, and literary elements theory. The research is a qualitative research with content analysis method. The main source of the data was a novel entitled Secret Daughter. The data were collected by reading and re-reading, noting, identifying, classifying and categorizing, analyzing and interpreting. The triangulation method was also used to obtain the validity and credibility of the findings. The findings are as follows: (1) Asha experiences identity diffusion status, identity foreclosure status, identity moratorium status, and identity achievement status which mark her identity crisis; (2) Asha is able to establish intimacy and obtain the virtue of love by forming relationship, establishing the sense of trust, understanding others, and acknowledging others; and (3) the author reflectspsychosocial issues through characters and settings.Keywords: adolescent, Gowda’s Secret Daughter, identity crisis, identity statuses,psychosocia
Vivisection and late-Victorian literary culture
No full textThe nineteenth-century antivivisection movement was supported by a striking number of poets, authors, and playwrights who attended meetings, signed petitions, contributed funds, and lent their pens to the cause. Yet live animal experimentation also permeated the Victorian imagination and shaped British literary culture in ways that the movement against it did not anticipate and could not entirely control. This is the first sustained literary-critical study of the topic. It traces responses to the practice through an extensive corpus of canonical, popular, and ephemeral texts including newspapers, scientific books, and government documents. Asha Hornsby sheds light on the complex entanglement of art and science at the fin-de-siècle and explores how the representational and aesthetic preoccupations opened up by vivisection debates often sat uneasily alongside a socio-political commitment to animal protection. Despite efforts to present writing and vivisecting as rivalrous activities, author and experimenter, pen and scalpel, often resembled each other
The Effectiveness of Different Revision Approaches in Science on Achievement and Retention of Learners Having Different Learning Styles
No full textNot availabl
Asha Kirana: Working With Angels
No full textabstract: Asha Kirana: Working with Angels is a documentary about the HIV/AIDS epidemic in Southern India and how one hospital has taken the lead in giving their patients, especially children, a better quality of life. The documentary film uses the story of one hospital and the doctors working there to illustrate a larger problem with the treatment of people living with HIV/AIDS in India. The goal of this film is to start a conversation about how India can help to destigmatize HIV/AIDS. The film uses a positive message of education, hope and passion to show how doctors and patients in India have already begun to reverse the stigma surrounding HIV in their community and how they hope to expand their efforts in the future. This project includes a written methodology explaining the goals for the film which include: showing how infected women and children in India are perceived, how important counseling is for a person with a terminal illness and how important education is in de-stigmatization of HIV/AIDS. The methodology also explains the current situation of the HIV/AIDS epidemic in India, the inspiration behind the film and the ways in which this film can create social change in India. The entire process of creating this documentary is also explained in a first-person narrative from the filmmaker. This gives insight into the filming process, immersion into another culture, how sources were cultivated, how interviews were conducted, restrictions and obstacles during the filming process, how those issues were overcome and the filmmaker's personal reflections
IDENTITY CRISIS IN ADOLESCENCE PERIOD EXPERIENCED BY ASHA IN SHILPI SOMAYA GOWDA’S SECRET DAUGHTER
No full textThis research aims to identify the identity statuses which mark the identity crisis of the main character in Gowda’s Secret Daughter, Asha, an Asian-Indian adolescent who lives in America with her adoptive mixed-race parents, to find out the impact of Asha’s identity crisis towards her sixth stage of psychosocial development, and to identify how the psychosocial issue is reflected in the novel. To answer the objectives, this research employed Erikson’s fifth and sixth psychosocial development stages theory, Marcia’s identity achievement status to strengthen the research, and theory of literary elements.
The research is a qualitative research. To analyze the data, content analysis method was used. The main source of this research is a novel entitled Secret Daughter by Shilpi Somaya Gowda. The data are words, phrases, sentences, and expressions related to the identity statuses which mark identity crisis, the impact of identity crisis towards the sixth stage of psychosocial development, and how the psychosocial issue is reflected. The data were collected by reading and re-reading, noting, identifying, classifying and categorizing, analyzing and interpreting. The triangulation method was also used to obtain the validity and credibility of the findings.
The findings of this research are as follows: (1) Asha experiences all four identity statuses which mark her identity crisis: identity diffusion status, identity foreclosure status, identity moratorium status, and identity achievement status; (2) Asha has a positive outcome of identity crisis as seen through her ability to establish intimacy and obtain the virtue of love at the sixth stage of her psychosocial development by forming relationship, establishing the sense of trust, understanding others, and acknowledging others; and (3) the author reflects psychosocial issues through characters and settings.
Keywords: adolescent, Gowda’s Secret Daughter, identity crisis, identity statuses, psychosocia
Novel somatic and germline mutations in cancer candidate genes in glioblastoma, melanoma, and pancreatic carcinoma
No full textA recent systematic sequence analysis of well-annotated human protein coding genes or consensus coding sequences led to the identification of 189 genes displaying somatic mutations in breast and colorectal cancers. Based on their mutation prevalence, a subset of these genes was identified as cancer candidate (CAN) genes as they could be potentially involved in cancer. We evaluated the mutational profiles of 19 CAN genes in the highly aggressive tumors: glioblastoma, melanoma, and pancreatic carcinoma. Among other changes, we found novel somatic mutations in EPHA3, MLL3, TECTA, FBXW7, and OBSCN, affecting amino acids not previously found to be mutated in human cancers. Interestingly, we also found a germline nucleotide variant of OBSCN that was previously reported as a somatic mutation. Our results identify specific genetic lesions in glioblastoma, melanoma, and pancreatic cancers and indicate that CAN genes and their mutational profiles are tumor specific. Some of the mutated genes, such as the tyrosine kinase EPHA3, are clearly amenable to pharmacologic intervention and could represent novel therapeutic targets for these incurable cancers. We also speculate that similar to other oncogenes and tumor suppressor genes, mutations affecting OBSCN could be involved in cancer predispositio
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