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Yayın An integrated circuit with transmit beamforming flip-chip bonded to a 2-D CMUT array for 3-D ultrasound imaging(IEEE-INST Electrical Electronics Engineers Inc, 2009-10) Wygant, Ira O.; Jamal, Nafis S.; Lee, Hyunjoo J.; Nikoozadeh, Amin; Oralkan, Ömer; Karaman, Mustafa; Khuri-Yakub, Butrus ThomasState-of-the-art 3-D medical ultrasound imaging requires transmitting and receiving ultrasound using a 2-D array of ultrasound transducers with hundreds or thousands of elements. A tight combination of the transducer array with integrated circuitry eliminates bulky cables connecting the elements of the transducer array to a separate system of electronics. Furthermore, preamplifiers located close to the array can lead to improved receive sensitivity. A combined IC and transducer array can lead to a portable, high-performance, and inexpensive 3-D ultrasound imaging system. This paper presents an IC flip-chip bonded to a 16 x 16-element capacitive micromachined ultrasonic transducer (CMUT) array for 3-D ultrasound imaging. The IC includes a transmit beamformer that generates 25-V unipolar pulses with programmable focusing delays to 224 of the 256 transducer elements. One-shot circuits allow adjustment of the pulse widths for different ultrasound transducer center frequencies. For receiving reflected ultrasound signals, the IC uses the 32-elements along the array diagonals. The IC provides each receiving element with a low-noise 25-MHz-bandwidth transimpedance amplifier. Using a field-programmable gate array (FPGA) clocked at 100 MHz to operate the IC, the IC generated property timed transmit pulses with 5-ns accuracy. With the IC flip-chip bonded to a CMUT array, we show that the IC can produce steered and focused ultrasound beams. We present 2-D and 3-D images of a wire phantom and 2-D orthogonal cross-sectional images (B-scans) of a latex heart phantom.Yayın Benefiting innovative capabilities of software developer/user communities in developing countries(IEEE, 2010) Ansal, Hacer; Yıldırım, NihanSince technological innovation is generally considered to be a major force in global economic growth, the development of innovative capabilities in developing countries has been a very important policy issue. Free/Libre Open Source Software (FLOSS) has reshaped software technology through the creation of developer/user communities which enabled the collaboration of different parties resulting in the production of Linux and similar software projects. FLOSS user/developer community networks serve not only as "learning, reviewing, and testing" environments for developers, but they may also act as innovation networks that contribute to the improvement of the innovative capabilities of individual developers within the community. Therefore, understanding the characteristics, the motivating factors and the innovative dynamics of these developer communities will provide valuable insight into how to improve the innovative capabilities of developing countries in relation to software.The aim of this paper is to explore the characteristics of FLOSS developer communities in order to discover what benefits they may offer developing countries in generating innovative capabilities related to software. By conducting a survey in the FLOSS user/developer community in Turkey, the demographic characteristics, motivation factors and innovative characteristics of the community are explored and the question of whether these communities may act as innovation networks is examined. It is concluded that FLOSS community networks mostly serve as knowledge sharing and collaboration platforms, however, they do have the potential to evolve into innovation networks if they receive support from the local software industry and academic institutions.Yayın Integration of 2D CMUT arrays with front-end electronics for volumetric ultrasound imaging(IEEE-INST Electrical Electronics Engineers Inc, 2008-02) Wygant, Ira O.; Zhuang, Xuefeng; Yeh, David T.; Oralkan, Ömer; Ergün, Arif Sanlı; Karaman, Mustafa; Khuri-Yakub, Butrus ThomasFor three-dimensional (3D) ultrasound imaging, connecting elements of a two-dimensional (2D) transducer array to the imaging system's front-end electronics is a challenge because of the large number of array elements and the small element size. To compactly connect the transducer array with electronics, we flip-chip bond a 2D 16 x 16-element capacitive micromachined ultrasonic transducer (CMUT) array to a custom-designed integrated circuit (IC). Through-wafer interconnects are used to connect the CMUT elements on the top side of the array with flip-chip bond pads on the back side. The IC provides a 25-V pulser and a transimpedance preamplifier to each element of the array. For each of three characterized devices, the element yield is excellent (99 to 100% of the elements are functional). Center frequencies range from 2.6 MHz to 5.1 MHz. For pulse-echo operation, the average -6-dB fractional bandwidth is as high as 125%. Transmit pressures normalized to the face of the transducer are as high as 339 kPa and input-referred receiver noise is typically 1.2 to 2.1 mPa/root Hz. The flip-chip bonded devices were used to acquire 3D synthetic aperture images of a wire-target phantom. Combining the transducer array and IC, as shown in this paper, allows for better utilization of large arrays, improves receive sensitivity, and may lead to new imaging techniques that depend on transducer arrays that are closely coupled to IC electronics.Yayın Virtual team effectiveness using dyadic teams(IEEE, 2007) Karayaz, Gamze; Keating, Charles B.The importance of effectiveness for virtual teamwork continues to gain momentum as technology and globalization of work accelerate. The implementation of virtual teams provides one approach to enhance competitiveness, overcoming the disadvantages of space and time differences through collaborative technologies. The influence of structure to virtual team performance has not been clearly established in the literature. The purpose of this research study was to investigate the effectiveness of a dyad structured approach for virtual teams using a quasi-experimental research design. A virtual dyadic team is considered as two person-structured teams working on a particular task in a virtual collaborative environment. This research investigated four questions related to the influence of structure on virtual team effectiveness related to task performance, communication frequency, and team satisfaction.The results showed significance differences between the two virtual teams. Dyadic teams performed better in arriving at the task solution using less communication to finish the task. Dyadic teams were also more satisfied with their task solution than the self-structured teams. However, results indicated that dyadic teams were not satisfied with operating as a dyadic team in this study. The research also demonstrated that team satisfaction was the most significant predictor of virtual team effectiveness. The paper concludes with implications for technology managers and suggests guidance for improved effectiveness in design and implementation of virtual teams.Yayın Research characteristics and agenda of technology management discipline in Turkey(IEEE, 2008) Ansal, Hacer; Aygören, Huriye; Ekmekci, Cavit UmutDespite the growing importance of "Technology Management" (TM) field in advanced countries since 1990s, it is rather new for developing countries such as Turkey. Considering the diversity of needs and concerns in different countries, the evolution of TM discipline can be expected to follow different paths to include different national experiences and to consider unique national needs and concerns in relation with technology management. Therefore, to what extent this diversity is reflected in the mainstream TM research agenda is an important issue. Thus, the aim of this study is in two folds; first, to examine how the general research characteristics and agenda of TM discipline have evolved in the academic research in Turkey, and next, to what extent they have converged or diverged with the patterns of mainstream TM research in international journals, by analyzing the TM articles published by Turkish academics both in the national and international scientific journals. The findings of this research reveal that the TM discipline in Turkey indicate both divergent and convergent characteristics when compared with the results of recent studies about developed and developing countries. In addition, a significant difference is observed about how these characteristics are reflected in national and international journals.Yayın Current benefits and future directions of NFC services(IEEE, 2010) Ok, Kerem; Coşkun, Vedat; Aydın, Mehmet Nafiz; Özdenizci Köse, BüşraNear Field Communication (NFC), as an emerging and promising technology, is an integration of Radio Frequency Identification (RFID) technology with mobile devices. NFC-enabled mobile devices can act as contactless smart cards and are also capable to read and write data from/to those cards. Research endeavours concerning NFC appear to focus mainly on development of NFC enabled services and applications. On the other hand, benefits and underlying values associated with different NFC applications' service is not yet well elaborated. In this paper we examined existing NFC applications, prototypes and studies from both academia and industry. We analyzed these applications by classifying them into NFC operating modes to surface the nature of underlying value-added services and benefits that they provide. Moreover we emphasized possible future usage scenarios together with directions and questions for future research based on the identified benefits.Yayın Exploring underlying values of NFC applications(Int Assoc Computer Science & Information Technology Press-Iacsit Press, 2011-08-19) Ok, Kerem; Aydın, Mehmet Nafiz; Coşkun, Vedat; Özdenizci Köse, BüşraNear Field Communication (NFC) is an integration of contactless smart card communication technology into mobile devices, such as mobile phones. NFC technology provides three operating modes and each mode differs from each other in terms of communication and data processing model. Each mode has distinguishable properties, advantages, and disadvantages; so that each one provides different possible business opportunities and different value-added perspectives. In this paper we survey currently available NFC applications as well as application prototypes. Afterwards, we analyzed those applications in order to find out which benefits they provide.Yayın MUNICIPAL: A decision technology for the restoration of critical infrastructures(Institute of Industrial Engineers, 2013) Loggins, Ryan A.; Wallace, William Al; Çavdaroğlu, BurakThis paper describes the decision technology MUNICIPAL (Multi-Network Interdependent Critical Infrastructure Program for the Analysis of Lifelines). This technology supports decision makers in the restoration of critical infrastructure systems after an extreme event. MUNICIPAL consists of four components: a vulnerability simulator which predicts damage to infrastructure components given a specific disaster scenario, an optimization module which produces a restoration plan given a damage scenario, a GIS interface to visualize and manipulate the data, and a database structured to support the data needs and integration of the other three modules. A case study was developed with the emergency management department of New Hanover County, North Carolina, to assess the technology with respect to the impact of a hurricane.Yayın Internationalisation of R&D into Emerging Markets: Fiat's R&D in Brazil, Turkey and India(Elsevier Sci Ltd, 2014-02) Athreye, Suma; Tuncay Çelikel, Aslı; Ujjual, VandanaThe idea that competence-creating subsidiaries from emerging nations can contribute to and possibly renew sources of competitive advantage is an appealing one for managerial practice and policy. Many mature MNEs can look to exploit the technological and market capabilities of their more capable subsidiaries in order to tap into new sources of growth. Based on a case study of Fiat and three of its emerging market R&D subsidiaries, we show that successfully developing competence-creating subsidiaries is a difficult task. Not only do parent and subsidiary managements have different ideas of what is involved, but subsidiary technological capability and local resources do not fully explain new technology creation mandates. The success of overall product market strategies and the mode of entry also exercise important effects. Furthermore, in our case study we find that internal embeddedness is more crucial than external embeddedness in distinguishing a successful new technology creation mandate.Yayın Free software, business capital, and institutional change: a veblenian analysis of the software industry(M. E. Sharpe Inc, 2012-12) Koloğlugil, Serhat; Koloğlugil, SerhatFree software, unlike proprietary software under exclusive copyright control, exemplifies a form of productive and innovative activity that is based upon mutual sharing of technological knowledge. Free software engineers, who get connected through various software-development projects, voluntarily contribute their time and skills to produce computer programs which, they insist, should be free for anyone to use, modify, and distribute. This paper argues that Thorstein Veblen's socio-economic theory - in particular his conceptions of capital, technological knowledge and institutional change - offers a fruitful framework to analyze the emergence of free software as an economic and social phenomenon. From the Veblenian perspective, the free software movement argues that the technological knowledge in the software industry should freely be available to society as a part of its common stock of knowledge. In other words, they are against the use of copyright law as a predatory strategy by software corporations, while the current technological conditions in the software industry allow for an institutional arrangement of production and innovation based on cooperative habits of thought.
