• Journal of the Institute of Electronics Engineers of Korea TC
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• v.49 no.6
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• pp.8-14
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• 2012

In this paper the core technologies of LTE/LTE-Adv systems which may enable the accommodation of huge mobile traffic today are introduced and investigated in order to provide some insights for future boradband mobile services provisioning. One of the key requirements for realization of broadband mobile services is to improve the efficiency of frequency usage and also stable performance of the LTE networks is indispensible to future use. In this sense, key technological issues are summarized hereafter and the technological breakthroughs required for the optimized operation of the networks are briefly discussed.

• Proceedings of the Technology Innovation Conference
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• 1997.12a
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• pp.104-130
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• 1997

This study empirically examined different patterns of collaborative R&D project with their key success factors(KSFs), using data from 80 projects in the Korean electronic parts industry The patterns in this study were categorized into 4 types by two criteria : product types(off-the-shelf/unique) and project initiator (focal/partner). The bivariate relationships revealed that project characteristics (technological complexity, demand certainty), partner characteristics(the number of partners, precious experience), process characteristics (participation in the project formulation, specificity of the collaboration process and outcomes) appear to be different among four types of collaboration. Furthermore, this study found that each type of collaborative R&D projects has different KSFs for their commercial success. The KSFs of type 1 (off-the-shelf product and focal organization initiation), for instance, include the strategic importance of the project, the problem solving performance of the focal organization while those of type 4(unique product and partner initiation) are technological complexity, demand certainty, reliability of partner relationship, specificity of the goals, specificity of the process and outcomes, information sharing. Finally, based on this empirical results, managerial, policy, and theoretical implications of the study were discussed.

• Journal of the Korea Fashion and Costume Design Association
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• v.1 no.1
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• pp.5-16
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• 1999

The purpose of this study is to identify the distinctive characterics HYBRID, strictly defined, an offspring that is a cross between different species, genera, or, in rare cases, families, More loosely defined, a hybrid can also be a cross between parents of different subspecies or varieties of a species. Hybrid varieties of plants and animals are of economic value because the hybrid is nearly always more vigorous, larger, and more fertile than either of its parents. Plant and animal hybrids may arise spontaneously in nature or may be produced intentionally by man. Forward-looking fashion explores progress. Adjusting to a world that has integrated genetics and its mutations, the new silhouette seems without references, as if born from a spontaneous generation. A slightly bizarre composite, asymmetrical, discreetly technological aesthetic, it draws on the latest technological details. the pursuit of performance and ergonomics, yet also of comfort and amusement that takes into account the body and its articulations, generates strange garments. Inspired by medical protheses. Focos on fabric touches, their weightiness and surface effects obtained with silicone, rubber or wax. in a range that highlights yellows but can also contrast with colder, slightly surgical hues, the hybrid woman doesn't necessarily want to stand out.

• Journal of Engineering Education Research
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• v.15 no.1
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• pp.53-60
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• 2012

On the grounds of Diane Vaughan's pioneering study into the Challenger Disaster, STS(Science and Technology Studies) scholars have recently argued that most engineers seldom face an ethical situation, in which the boundary between the ethical and the unethical is absolutely clear, and for which a serious moral decision such as "whistle blowing" is urgently needed. They have instead suggested that engineering ethics needs to address engineers' everyday routine practices, which, if accumulated, may have some impact upon the overall performance of the technological system. However, such studies have not completely resolved the tension between STS that emphasizes contextual elements in which the everyday practice of engineers are done, on the one hand, and engineering ethics that stresses individual engineer's moral decision of an existential kind, on the other. By discussing various works on the Challenger Disaster and related issues over technological risks, this paper attempts to establish an interface between STS and engineering ethics, and proposes some practical implications for the effective education of engineering ethics to engineering students.

• Proceedings of the KAIS Fall Conference
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• 2011.12b
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• pp.529-532
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• 2011

Recently research efforts for ubiquitous technology that includes RFID(Radio Frequency Deification and sensor networks are conducted very actively The architectural framework of the USN sensor network discovery service. The survey of the USN technology is conducted on four technological visions that contain USN system technology USN networking technology and USN middleware along with the service platform, With respect to each technological division domestic and worldwide leading research projects are primarily explored with their technical features and research projects are primarily explored with their technical features and research outputs. Boasted on the result of the survey we establish a USN software model that includes data sensing, sensor data storage sensor data storage sensor data naming and sensor feed name service. This main objective of this model is to provide a reference model for the facilitation of USN application developments.

• Journal of Power Electronics
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• v.15 no.6
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• pp.1524-1532
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• 2015

Conventional space vector pulse width modulation based asymmetrical dual inverter configuration produces high common mode voltage (CMV) variations. This CMV causes the flow of common mode current, which adversely affects the motor bearings and electromagnetic interference of nearby electronic systems. In this study, a simple and generalized carrier based pulse width modulation (PWM) technique is proposed for dual inverter configuration. This simple approach generates various continuous and discontinuous modulating signals based PWM algorithms. With the application of the discontinuous modulating signal based PWM algorithm to the asymmetrical dual inverter configuration, the CMV can be reduced with a slightly improved quality of output voltage. The performance of the continuous and discontinuous modulating signals based PWM algorithms is explored through both theoretical and experimental studies. Results show that the discontinuous modulating signal based PWM algorithm efficiently reduces the CMV and switching losses.

• The Journal of Information Systems
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• v.19 no.1
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• pp.149-177
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• 2010

Radio Frequency Identification(RFID) is rapidly growing the attention of many firms as a care technology for their businesses. As RFID moves into the mainstream, it replaces the standard barcodes that is used to identify and track products for a long time. With the intention of gaining competitive advantages, some firms have started the changeover to RFID technology while others have been disinclined to adopt it. Thus, this study examines firms as an attempt to identify key organizational characteristics driving the ear1y adoption and successful implementation of RFID. Results from 228 adopting organizations show Organizational Needs(Ubiquity and Performance Gaps), Technological Factors(Perceived Benefits and Perceived Cost Savings) and RFID Reduced Risk have a significant influence on RFID initiation. In addition, Trust Factors(Institutional Trusts and Inter-organizational Trusts) have a significant impact on RFID Reduced Risk. Finally, Organizational Readiness(Financial Resources and Technological Knowledge) have a significant influence as moderating effects between RFID initiation and adoption. The implications of the findings propose a new theoretical framework for the future IT/IS adoption study and offer suggestions for RFID researchers and practitioners in the development of the technology.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.2180-2200
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• 2015

This paper considers mobility control to improve packet delivery in delay-tolerant networks (DTNs) under group mobility. Based on the group structure in group mobility, we propose two mobility control techniques; group formation enforcement and group purposeful movement. Both techniques can be used to increase the contact opportunities between groups by extending the group's reachability. In addition, they can be easily integrated into some existing DTN routing schemes under group mobility to effectively expedite the packet delivery. This paper is divided into 2 parts. First, we study how our proposed mobility control schemes reduce the packet delivery delay in DTNs by integrating them into one simple routing scheme called group-epidemic routing (G-ER). For each scheme, we analytically derive the cumulative density function of the packet delivery delay to show how it can effectively reduce the packet delivery delay. Then, based on our second proposed technique, the group purposeful movement, we design a new DTN routing scheme, called purposeful movement assisted routing (PMAR), to further reduce the packet delay. Extensive simulations in NS2 have been conducted to show the significant improvement of PMAR over G-ER under different practical network conditions.

• Coupled systems mechanics
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• v.5 no.4
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• pp.315-327
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• 2016

Undergoing large volumetric changes upon incremental environmental stimulation, hydrogels are interesting materials which hold immense potentials for utilization in a wide array of applications in diverse industries. Owing to the large magnitudes of deformation it undergoes, swelling induced instability is a commonly observed sight in all types of gels. In this work, we investigate the instability of photo-thermal sensitive hydrogels, produced by impregnating light absorbing nano-particles into the polymer network of a temperature sensitive hydrogel, such as PNIPAM. Earlier works have shown that by using lights of different intensities, these hydrogels follow different swelling trends. We investigate the possibility of utilizing this fact for remote switching applications. The analysis is built on a thermodynamic framework of inhomogeneous large deformation of hydrogels and implemented via commercial finite element software, ABAQUS. Various examples of swelling induced instabilities, and its corresponding dependence on light intensity, will be investigated. We show that the instabilities that arise have their morphologies dependent on the light intensity.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.11
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• pp.4291-4310
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• 2015

This paper investigates the traffic offloading over unlicensed bands for two-tier multi-mode small cell networks. We formulate this problem as a Stackelberg game and apply a hierarchical learning framework to jointly maximize the utilities of both macro base station (MBS) and small base stations (SBSs). During the learning process, the MBS behaves as a leader and the SBSs are followers. A pricing mechanism is adopt by MBS and the price information is broadcasted to all SBSs by MBS firstly, then each SBS competes with other SBSs and takes its best response strategies to appropriately allocate the traffic load in licensed and unlicensed band in the sequel, taking the traffic flow payment charged by MBS into consideration. Then, we present a hierarchical Q-learning algorithm (HQL) to discover the Stackelberg equilibrium. Additionally, if some extra information can be obtained via feedback, we propose an improved hierarchical Q-learning algorithm (IHQL) to speed up the SBSs' learning process. Last but not the least, the convergence performance of the proposed two algorithms is analyzed. Numerical experiments are presented to validate the proposed schemes and show the effectiveness.