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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 The survey on Near Field Communication(MDPI, 2015-06) Coşkun, Vedat; Özdenizci Köse, Büşra; Ok, KeremNear Field Communication (NFC) is an emerging short-range wireless communication technology that offers great and varied promise in services such as payment, ticketing, gaming, crowd sourcing, voting, navigation, and many others. NFC technology enables the integration of services from a wide range of applications into one single smartphone. NFC technology has emerged recently, and consequently not much academic data are available yet, although the number of academic research studies carried out in the past two years has already surpassed the total number of the prior works combined. This paper presents the concept of NFC technology in a holistic approach from different perspectives, including hardware improvement and optimization, communication essentials and standards, applications, secure elements, privacy and security, usability analysis, and ecosystem and business issues. Further research opportunities in terms of the academic and business points of view are also explored and discussed at the end of each section. This comprehensive survey will be a valuable guide for researchers and academicians, as well as for business in the NFC technology and ecosystem.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 Economic impacts of increased U.S. exports of natural gas: An energy system perspective(MDPI AG, 2016-05-25) Sarıca, Kemal; Tyner, Wallace E.With the recent shale gas boom, the U.S. is expected to have very large natural gas resources. In this respect, the key question is would it be better to rely completely on free market resource allocations which would lead to large exports of natural gas or to limit natural gas exports so that more could be used in the U.S.. After accounting for the cost of liquefying the natural gas and shipping it to foreign markets, the current price difference leaves room for considerable profit to producers from exports. In addition, there is a large domestic demand for natural gas from various sectors such as electricity generation, industrial applications, and the transportation sector etc. A hybrid modeling approach has been carried out using our version of the well-known MARket ALlocation (MARKAL)-Macro model to keep bottom-up model richness with macro effects to incorporate price and gross domestic product (GDP) feedbacks. One of the conclusion of this study is that permitting higher natural gas export levels leads to a small reduction in GDP (0.04%-0.17%). Higher exports also increases U.S. greenhouse gas (GHG) emissions and electricity prices (1.1%-7.2%). We also evaluate the impacts of natural gas exports in the presence of a Clean Energy Standard (CES) for electricity. In this case, the GDP impacts are similar, but the electricity and transport sector impacts are different.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 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.
