• Steel and Composite Structures
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• v.45 no.1
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• pp.67-82
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• 2022

In this paper, buckling and free vibration of imperfect, functionally graded beams, including porosities, are investigated, using a higher order shear strain theory. Due to defects during the manufacturing process, micro porosities may appear in the material, hence the appearance of this imperfection in the structure. The material properties of the beams are assumed to vary regularly, with power and sigmoid law, in the direction of thickness. A novel porosity distribution affecting the functionally graded volume fraction is presented. For the compact formulation used for cementite-based materials and already used in P-FGM, we have adapted it for the distribution of S-FGM. The equations of motion in the FG beam are derived using Hamilton's principle. The boundary conditions for beam FG are assumed to be simply supported. Navier's solution is used to obtain the closed form solutions of the FG beam. The numerical results of this work are compared with those of other published research to verify accuracy and reliability. The comparisons of different shear shape functions, the influence of porosity, thickness and inhomogeneity parameters on buckling and free vibration of the FG beam are all discussed. It is established that the present work is more precise than certain theories developed previously.

• Journal of English Language & Literature
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• v.55 no.1
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• pp.83-105
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• 2009

Modern poetry begins as criticism of modernity and, by so doing, rejects its idea of time. Modernity emphasizes sequential, linear, and irreversible time and progress. Williams rejects the modern view of time, and attempts to substitute literature for history assuming that literature can take us into the immediacy of time. His poetry asserts the true moment of experience as an immediacy, of words co-existent with things. He suggests that modernity and its idea of time already led to World War I and could clearly lead to an actual, manmade apocalypse with continued technological progress. Already in the 1920s, Williams sensed that he was living in a world where such an end could come all true, which is why Spring and All, his greatest early achievement, begins with a parody of the modern apocalypse. Throughout the work, Williams criticizes "crude symbolism" and expresses his longing to annihilate "strained associations," for he believes that the metaphoric or symbolic association is related to order, the center, and the traditional concept of time itself. The metonymic model of Spring and All substitutes a self-reflexive, open-ended, and indeterminate structure of time for the linear and closed one. Instead of supplying an end, Williams only asserts the rebirth of time and attempts to arrive at immediacy while attacking the mediacy of traditional art. His characteristic use of fragmentation and abrupt juxtapositions disrupts the reader's generic, conceptual, syntactic, and grammatical expectations. His radical poetic experiments, such as the isolation of words and the disruption of syntax, produce a sense of immediacy and force the reader to confront the presence of the poem. His destruction of traditional forms, of the tyrannous designs of history and time, opens up rather than closes the possibility of signification, and takes us into a moment of beginning while disallowing temporal distancing. Spring and All, as a criticism of the modern idea of time, asks us to view Williams's work not as an ahistorical text but as a cultural subversion of modernity.

• Journal of English Language & Literature
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• v.55 no.1
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• pp.153-176
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• 2009

This paper attempts an allegorical reading of female sexuality in Henry James' The Aspern Papers, wherein the narrator reveals his obsession with the love letters of the dead poet, Jeffrey Aspern. Not only the old papers, but does he also fetishize female protagonists in order to maintain his belief in the "great poet." Discussing such fetishistic elements in the novella is in order firstly to reveal the self-splitting logic of phallocentric language, and secondly to analyze the limitation of such language, which resonates with the Freudian construction of female sexuality as critically presented by Irigary. The first part of this study explains the binary structure of The Aspern Papers crystalized in the symbolic courtship in the Bordereaus' garden. It also represents the psychological mindset of the narrator/protagonist: symbolically located "outside," the narrator describes the two Bordereaus as being closed "inside" in a dark mansion, concealing the precious papers from him and the public. In other words, the women are nothing but the obstacle for the self-elected agent, the narrator, from the publication of the language and ideas of the "great man". The women are associated with secrecy and surreptitiousness, while the man with transparency and the truth. Second part of this paper mimics this In/Out binary as a means to reveal insufficiency, if not impropriety, of the predominant discourse of female sexuality constructed and controlled from the male perspective. Employing Irigary's argument, this paper reads the female characters as allegory for female sexual organs, which explains the narrator's inevitable failure. That is, female sexuality is something that cannot be articulated by the intruding language of a masculine subject. since the female sex as such is not only plural but also harmonious and self-contained,

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.2
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• pp.61-71
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• 2014

A river fishway is a hydraulic structure enabling fish to overcome stream obstructions such as dams and weirs. The main aim of this paper is to investigate the collectibility of upstream-migrating fishes and hydraulic problems in pool-and-weir type fishway which has been established for upstream-migration at Namgang weir in the downstream of Namgang dam, and to grope for improvement measures which pool-and-weir type fishway can be switched to pool-and-partial weir type fishway through hydraulic field experiment. Exsisting fishway had problems which upstream-migrating fishes can not take a rest due to the seiche and vortex phenomena in pools and migrate to upstream because of height difference in entrance pool. In order to prevent hydraulically the seiche and vortex phenomena and establish rest area for fishes in each pool, we carried out hydraulic field experiments. In the fishway, it was to improve pool-and-weir into pool-and-partil weir, to decrease the height difference in entrance pool, and to reduce oriffice velocity of each pool. Also, we investigated fishes collectibility of after improving fishway for 6 days in September 2013. To resolve chronic problems(seiche-vortex phenomena and rest area for fishes), as weirs were remodeled into partial weir only which central part of weirs was part of non-overflow weir, we confirmed results that pool-and-weir type fishway could be switched to efficient pool-and-partial weir type fishway with relatively simple construction and low cost. Type-B which has the closed oriffices and the parts of non-overflow has the ideal conditions, but this conditions are limited to fishway of Namgang weir used in this study. Representative Ice-habor type fishway is pool-and-partial weir type fishway which has together parts of overflow and oriffices, and has excellent ability of upstream-migration. To switch from pool-and-weir type fishway to pool-and-partial weir type fishway, the size of oriffice has to be regulated by the discharge of fishway and the dimension on parts of non-overflow and overflow in weirs. Entrance pool is important facility which upstream-migrating fishes have to not only be collect but also charge with energy. In this study, entrance-pool is temporary and roughly-built, but fishes gather together more than the case of no entrance-pool. In the case of fishway which was protruded to downstream, as entrance of fishway turns toward or parallels to weir, the collectibility of fishway was excellent by attraction water.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.7
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• pp.135-142
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• 2015

Human-powered self-generating devices have been attractive with its operation characteristic independent from outer environment such as weather condition and wind speed. However, conventional self-generators have low electric power output due to their weakly-coupled electromagnetic structure. More importantly, rotary crank motion which is usually adopted by conventional self-generator to generate electricity requires specific skeletal muscles to maintain large torque circular motion and consequently, causes fatigue on those muscles before it can generate enough amount of electricity for any practical application. Without improvement in electric power output and usability, the human-powered self-generator could not be used in everyday life. This study aims to develop a human-powered self-generator which realized a strong electromagnetic coupling in a closed-loop tubular structure (hula-hoop shape) for easy and steady long-term driving as well as larger electric output. The performance and usability of the developed human-powered generator is verified through experimental comparison with a commercial one. Additionally, human workload which is a key element of a human-powered generator but not often considered elsewhere, is estimated based on metabolic energy expenditure measured respiratory gas analyzer. Further study will focus on output and portability enhancement, which can contribute to the continuous power supply of mobile equipments.

• Journal of Navigation and Port Research
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• v.31 no.5 s.121
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• pp.435-445
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• 2007

Ship structures are thin-walled structures and lots of cutouts, for example, of inner bottom structure, girder, upper deck hatch, floor and dia-frame etc. In the case where a plate has cutout it experiences reduced buckling and ultimate strength and at the same time the in-plane stress under compressive load produced by hull girder bending will be redistributed. In the present paper, we investigated several kinds of perforated stiffened model from actual ship structure and series of elasto-plastic large deflection analyses were performed to investigate into the influence of perforation on the buckling and ultimate strength of the perforated stiffened plate varying the cutout ratio, web height, thickness and type of cross-section by commercial FEA program(ANSYS). Closed-form formulas for predicting the ultimate strength of the perforated stiffened plate are empirically derived by curve fitting based on the Finite Element Analysis results. These formulas are used to evaluate the ultimate strength, which showed good correlation with FEM results. These results will be useful for evaluating the ultimate strength of the perforated stiffened plate in the preliminary design.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.11
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• pp.357-360
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• 1997

For medical students and doctors, knowledge of the 3-dimensional (3D) structure of the heart is very important in diagnosis and treatment of the heart diseases. 2-dimensional (2D) tools (e.g. anatomy book) or classical 3D tools (e.g. plastic model) are not sufficient or understanding the complex structures of the heart. Moreover, it is not always guaranteed to dissect the heart of cadaver when it is necessary. To overcome this problem, virtual dissection systems of the heart have been developed. But these systems are not satisfactory since they are made of radiographs; they are not true 3D images; they can not be used to dissect freely; or they can only be operated on the workstation. It is also necessary to make the dissection systems incorporating the various races and tribes because of the organ's difference according to race and tribe. This study was intended to make the 3D image of the heart from a Korean cadaver, and to establish a virtual dissection system of the heart with a personal computer. The procedures or manufacturing this system were as follows. 1. The heart from a Korean adult cadaver was embedded with gelatin solution, and serially cross-sectioned at 1mm-thickness on a meat slicer. Pictures or 153 cross-sectioned specimens were inputted into the computer using a digital camera ($756{\times}504$ resolution, true color). 2. The alignment system was established by means of the language of IDL, and applied to align 2D images of the heart. In each of 2D images, closed curves lining clean and dirty blood pathways were drawn manually on the CorelDRAW program. 3. Using the language of IDL, the 3D image and the virtual dissection system of the heart were constructed. The virtual dissection system of the heart allowed or ree rotation, any-directional sectioning, and selected visualization of the heart's structure. This system is expected to become more advanced, and to be used widely through Internet or CD-title as an educational tool for medical students and doctors.

• Journal of Hospice and Palliative Care
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• v.15 no.1
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• pp.1-9
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• 2012

Purpose: The aim of this study was to discuss challenges for hope seeking intervention based on individual experience (HSIBIE) in palliative care, assuming that hope is an individualized unique, subjective, and dynamic experience. Methods: Literature, including analysis and discussion, was reviewed to identify limitations and ways to develop HSIBIE. Results: This study identified following challenges: 1. Hope was often described and utilized as a standardized unified structure with varying attributes or mono-structure emphasizing a realistic hope, or both of them (relativism vs. monism) in one literature. This challenge is represented as a problem in conceptualization. 2. Few studies discussed various patterns of hope or individuals' unique experiences in palliative care. 3. The HSIBIE and the method for the HSIBIE have been rarely discussed. Conclusion: A problem in conceptualization is often related to fixed ideas formed over a long period and used in a closed circle of scholars and professionals. Therefore, such fixed ideas should be openly challenged with fresh perspectives. The second issue requires a cross-cultural studies of various hope experiences in palliative care, which can be used for effective and appropriate HSIBIE.

• Journal of Agricultural Extension & Community Development
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• v.16 no.2
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• pp.363-384
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• 2009

This study aimed at finding directions for Korean agriculture to establish a new paradigm of sustainable development. Various problematic issues and concerns in the environment necessitate the transformation of Korea's development paradigm from unconditional growth to "Green Growth" through new policies on green value and review of various advanced researches. In this research, the environment-friendly agriculture's problems, particularly in agribusiness were analyzed. Drawing from Michael Porter's Value Chain Analysis, this research developed a value chain model in agriculture that reflects the environment and the present situations. Future directions in the agriculture sector were also discussed. Korea realized food self-sufficiency through the green revolution in the early 1970s. However, a lot of problems have also occurred, including ground and water pollution and the destruction of ecosystems as a result of the overuse of pesticides and chemical fertilizers. In the late 1970s, the growing interest on environment-friendly agriculture led to the introduction of sustainable methods and techniques. Unfortunately however, these were not innovative enough to foster environment-friendly agriculture. Thereafter, the consumers' distrust on agricultural products has worsened and concerns about health have increased. In view of this, the Ministry of Food, Agriculture, Forestry and Fisheries introduced in December 1993 a system of Quality-Certified Products for organic and pesticide-free agri-foods. Although a fundamental step toward the sustainability of the global environment, this system was not enough to promote environment-friendly agriculture. In 2008, Korea's vision is for "Low Carbon Green Growth" to move forward while also coping with climate change. But primary sectors in a typical value chain do not consider the green value of their operations nor look at production from an environmental perspective. In order to attain sustainable development, there is a need to use less resources and energy than what is presently used in Korean agricultural and value production. The typical value chain should be transformed into a "closed-loop" such that the beginning and the end of the chain are linked together. Such structure allows the flow of materials, products and even wastes among participants in the chain in a sustained cycle. This may result in a zero-waste sustainable production without destroying the ecosystem.

• Sijohaknonchong
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• v.20
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• pp.75-96
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• 2004

A pavilion is located in the place with beautiful scenery, which maximizes the poetical features of nature. So a scholar in the Chosun Dynasty had the dream of possessing it. This trends of the Chosun scholar resulted in producing lots of literary works related with the pavilion. In this thesis, I researched the characters of Pavilion Si-Jo in accordance with the function of pavilion. First, the pavilion, which is surrounded by the beautiful scenery, is a good place to see the beauty of nature. It is needless to walk around to see the scenery thanks to its open structure. So the feeling in the pavilion Si-Jo is distinguished from other sightseeing Si-Jos: those show the way of seeing the scenery walking here and there, but this shows the way of seeing the scenery only just looking up, looking down, and looking in the distance. Second, the pavilion functions as an academic place. In this case, it can be said that it functions like a lecture hall. It is more effective to study in the pavilion than in the closed structure, a lecture hall. Furthermore, the scholar studying in the pavilion understand the principle of nature with seeing the beautiful mountain and river, and it can be a place for growing a vast-flowing spirit. This kind of poetry has been handed down with the Chinese poetry, and the character who operated the pavilion often appears in the work. Third, the pavilion functions as a space for a fraternity or poetry circles. The poetic exchange was conducted by host of pavilion. which is the key ingredient for organizing a poetry circles. Finally, the pavilion functions as an entertainment. Although it is a space for an entertainment, there is no deviation as a man of novel birth. If the pavilion has the feature of closeness, there are sometimes works which shows the deviation of them.