• Journal of Ship and Ocean Technology
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• v.12 no.1
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• pp.16-27
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• 2008

The interaction between advancing ships and the waves generated by them plays important roles in wave resistances and ship motions. Wave breaking phenomena near the ship bow at different speeds are investigated both numerically and experimentally. Numerical simulations of free surface profiles near the fore bodies of ships are performed and visualized to grasp the general trend or the mechanism of wave breaking phenomena from moderate waves rather than concentrating on local chaotic irregularities as ship speeds increase. Navier-Stokes equations are differentiated based on the finite difference method. The Marker and Cell (MAC) Method and Marker-Density Method are employed, and they are compared for the description of free surface conditions associated with the governing equations. Extra effort has been directed toward the realization of extremely complex free surface conditions at wave breaking. For this purpose, the air-water interface is treated with marker density, which is used for two layer flows of fluids with different properties. Adaptation schemes and refinement of the numerical grid system are also used at local complex flows to improve the accuracy of the solutions. In addition to numerical simulations, various model tests are performed in a ship model towing tank. The results are compared with numerical calculations for verification and for realizing better, more efficient research performance. It is expected that the present research results regarding wave breaking and the geometry of the fore body of ship will facilitate better hull form design productivity at the preliminary ship design stage, especially in the case of small and fast ship design. Also, the obtained knowledge on the impact due to the interaction of breaking waves and an advancing hull surface is expected to be applicable to investigation of the ship bow slamming problem as a specific application.

• The Journal of Information Systems
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• v.16 no.4
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• pp.131-155
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• 2007

The purpose of this thesis is to study on the philosophical analysis model and its methodological application of information systems research evaluation from critical realist perspective. Fist of all, I examine ontological epistemological methodological assertions of critical realism. Because the philosophy of critical realism is an opportunity for information systems study. I examine Dobson and Mutch's critical realist perspective on actors-structure model. I suggest a critical realist actors-praxis-structure model. This model provides the potential for a new approach to social investigations in its provision of an ontology for the analytical separation of structure and agency. Of most importance might be the incorporation of non-humans into the analysis of social interaction and of technology into the elaboration of structures. I also examine Tsoukas's critical realistic meta-theory of management. I suggest a critical realist IS management model. This model elucidate the nature of management and delineate the scope of applicability of various perspectives on management. The causal powers of management reside in the real domain and, taken together, their logics are contradictory, the effects of their contradictory composition are contingent upon prevailing contingencies. I analyze Carlsson's theory of design knowledge. His framework builds on that the aim of IS design science research is to develop practical knowledge for the design and realization of different classes of IS initiatives, where IS are viewed as socio-technical systems and not just IT artefacts. The framework proposes that the output of IS design science research is practical IS design knowledge in the form of field-tested and grounded technological rules. The IS design knowledge is developed through an IS design science research cycle. In conclusion, I think that IS actors-praxis-structure model, meta-theoretical IS management model, and IS design knowledge model according to critical realistic approach are very useful for IS research evaluation. Nevertheless, important problems are left not resolved.

• Journal of Convergence for Information Technology
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• v.7 no.6
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• pp.181-186
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• 2017

In recent years, robots have been actively used for children's creativity learning and play, but most robots have a stereotyped form and have a high dependency on the program, making it difficult to learn creativity and play. In order to compensate for these drawbacks, We have created a robot that can easily and reliably combine each other. The robot can memorize the desired operation and execute the memorized operation by using one button. Also, in case multiple modules are combined, pressing the button once on any module makes it possible to easily adjust the operation of all the combined modules. In order to verify the actual operation, two, three, and five modules are combined to demonstrate the usefulness of the proposed structure and algorithm by implementing a gobbling motion and a walking robot. It is required to study intelligent modular robots that can control over the Internet by supplementing the wireless connection method.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.10 s.89
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• pp.983-995
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• 2004

This paper introduces a pre-compensation filter for compensating dispersive and resonant properties experienced along the usage of non-ideal wideband antennas in impulse communication systems. It has been well blown that the transmitted impulse signal becomes deformed because of dispersive and resonant characteristics. Accordingly, in spite of using ideal template signal at the correlator in coherent receiver, these impairments degrade overall performance attributed to low level of coherence. To overcome this problem this paper exploits a realization technique of pre-compensation filter purposely installed at transmitter whose stability is automatically guaranteed because it has an inversion form of minimum-phase ARMA (Auto-Regressive Moving Average) system. The performance of proposed scheme will be shown in results from computer simulations to verify its affirmative impact on impulse communication system with regarding several distinctively shaped antennas.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.331-334
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• 2011

This is a study about a platform realization measuring the extent of reaction in nerve, as giving a electrical impulse on a nerve pulp regulating a function of muscle, about a measurement of nerve reaction in the amount of current, the lasting time of current, and the position of electrode from a electrical impuls.The position of an electrode in a electrical nerve impuls have nothing to do with all nerves from exercise to all things. There is the Single Twitch Stimulation(STS), Train-of-four(TOF), and Double Burst Stimulation(DBS) in the form of nerve stimulation. This report is needed for selecting MCU of low electric power for a base in embedded system and measuring the extent of reaction after making a sensor interface to know sensitivity of measuring sensor in basic reaction of nerve impuls. The platform is realized to select a high efficiency AD Convertor for raising accuracy in measured data. As the platform in this report was developed for a medical appliances, it was designed to consider user safety in electric power Isolation when making electric power circuit.

• Journal of radiological science and technology
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• v.24 no.2
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• pp.71-75
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• 2001

As the adoption of PACS and hospital information system among university hospitals and hospital level institutions grows bigger, the need of sharing and transferring medical information among medical institutions is rising. For the medical information, which is saved in the hospital medical system, to be transferred within the same hospital, domestic, or foreign medical institutions, a standard protocol is necessary. But realistically, most of the domestic hospitals do not abide by H7L which is the HIS standard and so, information transferring is not possible as of present. As such, the purpose of this research is to implement the information between HIS and PACS to an international standard by constructing HL7 messages through HL7 Interface. which will eventually make possible information transferring between different hospitals. Our research team has developed a method which will make the PACS equip hospitals that do not follow HL7 standard which will make possible to transfer information between HIS and PACS through HL7 Message. By constructing message files, which follow the form of HL7 Message in the HL7 Interface, they can be transferred to PACS through the ftp protocol. The realization of the HIS/OCS Interface through HL7 enables data transferring between domestic and foreign medical institutions possible by implementing the international standard in the PACS and HIS data transferring process. The HL7 that our research team has developed made patient data transfer between medical institutions possible. The Interface is for a specific system model and in order for the data transfer between different systems to be realized, interfaces that are fit for each system must be needed. If the interface is improvised and implemented to each hospital's information system, the data sharing among medical institutions can be broadened.

• Smart Structures and Systems
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• v.23 no.6
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• pp.589-613
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• 2019

Cables are prone to vibration due to their low inherent damping characteristics. Recently, negative stiffness dampers have gained attentions, because of their promising energy dissipation ability. The viscous inertial mass damper (termed as VIMD hereinafter) can be viewed as one realization of the inerter. It is formed by paralleling an inertial mass part with a common energy dissipation element (e.g., viscous element) and able to provide pseudo-negative stiffness properties to flexible systems such as cables. A previous study examined the potential of IMD to enhance the damping of stay cables. Because there are already models for common energy dissipation elements, the key to establish a general model for IMD is to propose an analytical model of the rotary mass component. In this paper, the characteristics of the rotary mass and the proposed analytical model have been evaluated by the numerical and experimental tests. First, a series of harmonic tests are conducted to show the performance and properties of the IMD only having the rotary mass. Then, the mechanism of nonlinearities is analyzed, and an analytical model is introduced and validated by comparing with the experimental data. Finally, a real-time hybrid simulation test is conducted with a physical IMD specimen and cable numerical substructure under distributed sinusoidal excitation. The results show that the chosen model of the rotary mass part can provide better estimation on the damper's performance, and it is better to use it to form a general analytical model of IMD. On the other hand, the simplified damper model is accurate for the preliminary simulation of the cable responses.

• The Research Journal of the Costume Culture
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• v.29 no.4
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• pp.572-584
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• 2021

The emergence of environmental and social issues has led to global discussions for the realization of sustainable development. The purpose of this study is to propose a method of sustainable fashion design using waste Hanbok, focusing on men's Hanbok with cultural values. The study utilizes literature research and fashion design development. From the literature study, reform was judged to be a higher concept encompassing reduction, recycling, and upcycling. Reduction is a design method through removal, and recycling design transforms from its original form into a completely different product. Upcycling design focuses on improvement and change in functionality. Accordingly, nine redesigns using men's Hanbok were developed from which three were produced. Consequently, the reduction design demonstrated a small range of variation without changing the item, and cultural sustainability was confirmed through the design that removed the components and recombined the Hanbok. Second, recycling redesign can be reconstituted into a different item. Third, upcycling enables various designs through module assembly, which prolongs the lifespan of the product and confirms its value as a raw material for waste Hanbok. This study is meaningful in realizing sustainable fashion and suggesting practical measures for the sustainability of Korean traditional culture and creative fashion design planning.

• English & American cultural studies
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• v.14 no.1
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• pp.73-94
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• 2014

Accounts from therapeutic culture seem often to associate the selfish, or at least self-centered quest for self-fulfillment with individual choice or satisfaction, self-expression, expressive individualism, and emotionalism. These associations point to the downside of therapy as they present it as constituting a culture of narcissism, selfishness, or irresponsibility. While some of these characterizations contain useful insights, they overlook what are maybe some of the most important features of a therapeutic outlook. This paper aims to reveal that the therapeutic imperative is not so much geared towards the realization of self-fulfillment, as it is the promotion of self-limitation. Therapeutic culture tends to posit the self in a fragile and feeble form and insist that the management of life requires the continuous intervention of therapeutic expertise. Because of this, the elevated concern with the self is underpinned by anxiety, pain, suffering, and survival, rather than seen as a positive vision of realizing the human potential. Therapeutic culture has in this way helped to construct a diminished sense of self by which one is seen as suffering from an emotional deficit and vulnerability. This paper demonstrates this downside of therapeutic culture concerning self-limitation and the sense of a diminished self by examining popular "misery memoirs." Misery memoirs are widely consumed by the general public, therefore tend to be treated by contemporary therapeutic culture as a gospel on the therapeutic ideal for self-fulfillment and self-discovery. This is, despite the existence of hidden evidence to the contrary, because of their redemptive, happy endings that show individuals overcoming difficult trials such as child abuse, incestuous rape, and domestic violence. Individual self-fulfillment and self-discovery in such stories are not achieved through the active agency of the subject but through the passive endurance of pathological symptoms and with the aid of expertise and outside support. Therefore, such stories put victims in the limited position.

• Journal of Ocean Engineering and Technology
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• v.35 no.6
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• pp.446-456
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• 2021

To build an environment facility of a large-scale ocean basin, various detailed reviews are required, but it is difficult to find data that introduces the related research or construction processes on the environment facility. The current generator facility for offshore structure safety evaluation tests should be implemented by rotating the water of the basin. However, when the water in the large basin rotates, relatively large flow irregularities may occur and the uniformity may not be adequate. In this paper, design and review were conducted to satisfy the performance goals of the DOEB through computational numerical analysis on the shape of the waterway and the flow straightening devices to form the current in the large tank. Based on this, the head loss, which decreases the flow rate when the large tank water rotates through the water channel, was estimated and used as the pump capacity (impeller) design data. The impeller of the DOEB current generator was designed through computational numerical analysis (CFD) based on the lift surface theory from the axial-type impeller shape for satisfying the head loss of the waterway and maximum current velocity. In order to confirm the performance of the designed impeller system, the flow rate and flow velocity performance were checked through factory test operation. And, after installing DOEB, the current flow rate and velocity performance were reviewed compare with the original design target values. Finally, by measuring the current velocity of the test area in DOEB formed through the current generator, the spatial current distribution characteristics in the test area were analyzed. Through the analysis of the current distribution characteristics of the DOEB test area, it was confirmed that the realization of the maximum current velocity and the average flow velocity distribution, the main performance goals in the waterway design process, were satisfied.