• Asia pacific journal of information systems
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• v.8 no.3
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• pp.181-194
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• 1998

The inability of the management information systems (MIS) field to progress as a scientific discipline has been attributed to the lack of systematic research and a cumulative tradition, an identity crisis, and the poverty of scientism. While research on the status of MIS is very important in order to enhance the field as a scientific discipline, few have investigated this issue. Following Thomas Kuhn's idea of paradigm, this paper studies other fields to investigate when they progressed, when they did not, and why. After research paradigm was broken down into technology-push and demand-pull types, a model on the science life cycle was developed in an effort to explain the path how a science has progressed. A test of this model in the fields of physics and chemistry with an old historial background reveals that the scientific progress in the area of demand-pull is more desirable if this progress turns out to be in the right direction. An application of the model to the MIS field shows that the research paradigm in this field is mainly of technology-push. In order to shift this paradigm toward the demand-pull area, this paper suggests the research on the relationship among MIS subfields and the adoption of appropriate reference disciplines.

• Steel and Composite Structures
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• v.35 no.2
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• pp.237-247
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• 2020

Shear connectors are essential elements in the design of steel-concrete composite systems. These connectors are utilized to prevent the occurrence of potential slips at the interface of steel and concrete. The two types of shear connectors which have been recently employed in construction projects are C- and L-shaped connectors. In the current study, the behavior of C and L-shaped angle shear connectors is investigated experimentally. For this purpose, eight push-out tests were composed and subjected to monotonic loading. The load-slip curves and failure modes have been determined. Also, the shear strength of the connectors has been compared with previously developed relationships. Two failure modes of shear connectors were observed: 1) concrete crushing-splitting and 2) shear connector fracture. It was found that the L-shaped connectors have less shear strength compared to C-shaped connectors, and decreasing the angle leg size increases the shear strength of the C-shaped connectors, but decreases the relative ductility and strength of L-shaped connectors.

• The Transactions of the Korean Institute of Power Electronics
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• v.27 no.5
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• pp.384-390
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• 2022

In this study, a single-stage, four-phase, interleaved, totem-pole AC-DC converter is proposed for a super-fast charger station that requires high power, a wide voltage range, and bidirectional operation capabilities and adopts various types of electric transport vehicles. The proposed topology is based on current-fed push-pull dual active bridge converter combined with the totem-pole operation. Owing to the four-phase interleaving effect, the bridge on the grid side can switch at 0.25, 0.5, and 0.75 to achieve a ripple-free grid current. The input filter can be removed theoretically. Switching methods for the duty of the secondary-side duty cycle are proposed, and they correspond to the primary duty cycle for reducing the circulating power and handling the total harmonic distortion. Therefore, the converter can operate under a wide voltage range. Experimental results from a 7.5 kW prototype are used to validate the proposed concept.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.2
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• pp.1-15
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• 2016

Objectives : This is a study for technological forecasting, aiming to find out the promising future technologies in KM(Korean Medicine) and deduce implications for the research and development of KM. Methods : The first pool of 145 technological tasks related to KM were composed by reviewing the existing data related to technological forecasting. The steering committee for the research set 99 final technological tasks. With the deduced technological tasks, mini-Delphi(2-round) method was conducted and 6 research items were used-the importance, realization time, urgency, technological competitiveness, the main agent that will push forward the task, and obstacles. Results : As a result on the time when the technology will be realized, 58 out of 99 technologies(59%) were predicted to be realized in the same year domestically and globally. The average of the importance of the 99 technological tasks was 72.9. Among them. As for the main agent to push forward the research and development of future technologies, 'industry-academic cooperation' took the highest portion at 58.7%, and regarding the obstacles to realize technological tasks, the lack of infrastructure(research funds) was the highest at 33.6%. Conclusions : This study shows that the development of basic technologies in the technologies of Korean medicine is insufficient and it is believed that the development of basic technologies is urgent to promote the development of application technologies.

• Steel and Composite Structures
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• v.34 no.6
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• pp.837-851
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• 2020

This study aims to examine the interface shear behavior between precast high-strength concrete slabs with pockets and steel beam to achieve accelerated bridge construction (ABC). Twenty-six push-out specimens, with different stud height, stud diameter, stud arrangement, deck thickness, the infilling concrete strength in shear pocket (different types of concrete), steel fiber volume of the infilling concrete in shear pocket concrete and casting method, were tested in this investigation. Based on the experimental results, this study suggests that the larger stud diameter and higher strength concrete promoted the shear capacity and stiffness but with the losing of ductility. The addition of steel fiber in pocket concrete would promote the ductility effectively, but without apparent improvement of bearing capacity or even declining the initial stiffness of specimens. It can also be confirmed that the precast steel-concrete composite structure can be adopted in practice engineering, with an acceptable ductility (6.74 mm) and minor decline of stiffness (4.93%) and shear capacity (0.98%). Due to the inapplicability of current design provision, a more accurate model was proposed, which can be used for predicting the interface shear capacity well for specimens with wide ranges of the stud diameters (from13 mm to 30 mm) and the concrete strength (from 26 MPa to 200 MPa).

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.11 no.6
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• pp.778-783
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• 2018

With the rapid advancement of information and communication technology and industrial technologies, a hyper-connected society is being realized to connect human beings, all programs and things via the Internet. IoT (Internet of Thing), which connects a thing and another thing, and things and human beings, gathers information to realize the hyper-connected society. MQTT (Message Queuing Telemetry Transport) is a push-technology-based light message transmission protocol that was developed to be optimized to the limited communication environment such as IoT. In pursuing the hyper-connected society, IoT's sensor environment information is now being used as a wide range of information on people's diseases and health management. Thus, security problems of such MQTT include not only the leak of environmental information but also the personal information infringement. To resolve such MQTT security problems, we have designed a new security MQTT communication by applying the initial-value sensitivity and pseudorandomness of the chaotic system to the integrity and confidentiality. The encryption method using our proposed chaotic system offers a simple structure and a small amount of calculation, and it is deemed to be suitable to the limited communication environment such as IoT.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.454-463
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• 2017

Advancement of science and technology have led to development of the media, which has evolved election campaign strategies. Nowadays, media development has made communication more important, and it is a growing trend where smart-device applications are widely used to facilitate communication with electors. Based on Google's Fire base Cloud Messaging (FCM) push service, which keeps up with the fast-changing election trends and supports election campaigns systematically, this research aims to help accomplish the goals of an election campaign by developing an information system and performing empirical analysis of the variables that the information system affects. The system consists of an elector's application and a management system. The management system includes browsing and management of received-and sent-message history, and direct management of the application. By managing the push system in more progressive ways, this system will help to improve the effectiveness of election campaigns and accomplish election goals.

• The Journal of Korean Physical Therapy
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• v.28 no.2
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• pp.106-111
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• 2016

Purpose: The aim of this study is to determine the effect of glenohumeral (GH) rotation position in modified knee push-up plus exercise (MKPUP) by examining the surface electromyography (EMG) amplitude in serratus anterior (SA), pectoralis major (PM), and upper trapezius (UTz) and the activity ratio of each muscle. Methods: A total of 22 healthy subjects volunteered for the study. Each subject performed the MKPUP at $0^{\circ}$, $45^{\circ}$, and $90^{\circ}$ of GH joint internal rotation. EMG of the SA and PM, UTz was compared between GH rotation positions and each muscle activity ratio. EMG was used to measure the muscle activity in terms of ratios to maximal voluntary isometric contraction (MVIC). Results: The difference in EMG activity during the exercise in three GH joint internal rotation positions was observed with the SA and the PM. The greater the GH joint internal rotation angle was, the lower the activity of the PM. In contrast, the SA showed higher activity. However, the activity of UT was similar under all conditions. The ratio of the SA and the PM was considerably greater at $90^{\circ}$ GH joint internal rotation than at $0^{\circ}$ and $45^{\circ}$. Conclusion: When excessive activation of the PM or imbalanced activation between the PM and the SA occurs, the MKPUP exercise is most effective at $90^{\circ}$ of GH joint internal rotation. Use of this position would be a beneficial strategy for selective strengthening of the SA and minimizing PM activation.

• Steel and Composite Structures
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• v.18 no.6
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• pp.1369-1389
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• 2015

In order to investigate the behaviour of lying multi-stud connectors in cable-pylon anchorage zone, twenty-four push-out tests are carried out with different stud numbers and diameters. The effect of concrete block width and tensile force on shear strength is investigated using the developed and verified finite element model. The results show that the shear strength of the lying multi-stud connectors is reduced in comparison with the lying single-stud connector. The reduction increases with the increasing of the number of studs in the vertical direction. The influence of the stud number on the strength reduction of the lying multi-stud connectors is decreased under combined shear and tension loads compared with under pure shear. Yet, due to multi-stud effect, they still can't be ignored. The concrete block width has a non-negligible effect on the shear strength of the lying multi-stud connectors and therefore should be chosen properly when designing push-out specimens. No obvious difference is observed between the strength reductions of the studs with 22 mm and 25 mm diameters. The shear strengths obtained from the tests are compared with those predicted by AASHTO LRFD and Eurocode 4. Eurocode 4 generally gives conservative predictions of the shear strength, while AASHTO LRFD overestimates the shear strength. In addition, the lying multi-stud connectors with the diameters of 22 m and 25 mm both exhibit adequate ductility according to Eurocode 4. An expression of load-slip curve is proposed for the lying multi-stud connectors and shows good agreement with the test results.

• Journal of Korea Spatial Information System Society
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• v.11 no.4
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• pp.47-55
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• 2009

As the wireless internet technology such as mobile phone, WIBRO, HSDPA develops, customized location-based services for traffic, tourism, shopping, and emergency relief has lately attracted attention. For giving customized services. we should consider dynamic characteristics of moving object which continuously change their location. In this paper, we define the context trigger type of moving object and design triggering method for processing context generated by moving object. Also we propose location-based push service platform including context trigger of moving object for supporting location-based information to user. The proposed system gathers moving object stream from the terminal based on MS-assisted or Stand-alone positioning mode of embedded GPS in terminal extract user context by user device agent, and send context information to server.