• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.755-767
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• 2020

A significant development has been made on a new fatigue damage model applicable to Gaussian wide band stress response spectra using numerical approximation methods such as data processing, time simulation, and regression analysis. So far, most of the alternative approximate models provide slightly underestimated or overestimated damage results compared with the rain-flow counting distribution. A more reliable approximate model that can minimize the damage differences between exact and approximate solutions is required for the practical design of ships and offshore structures. The present paper provides a detailed description of the development process of a new fatigue damage model. Based on the principle of the Gaussian wide band model, this study aims to develop the best approximate fatigue damage model. To obtain highly accurate damage distributions, this study deals with some prominent research findings, i.e., the moment of rain-flow range distribution MRR(n), the special bandwidth parameter μk, the empirical closed form model consisting of four probability density functions, and the correction factor QC. Sequential prerequisite data processes, such as creation of various stress spectra, extraction of stress time history, and the rain-flow counting stress process, are conducted so that these research findings provide much better results. Through comparison studies, the proposed model shows more reliable and accurate damage distributions, very close to those of the rain-flow counting solution. Several significant achievements and findings obtained from this study are suggested. Further work is needed to apply the new developed model to crack growth prediction under a random stress process in view of the engineering critical assessment of offshore structures. The present developed formulation and procedure also need to be extended to non-Gaussian wide band processes.

• Journal of English Language & Literature
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• v.56 no.6
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• pp.1211-1234
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• 2010

Mule Bone (1931), Zora Neale Hurston's collaboration with Langston Hughes, has been credited as the 'first' attempted by African Americans to create black folk comedy. The proposed research is driven from a question to the recent scholarship's tacit consent on such historic importance imposed on the play. This paper suggests a possibility that De Turkey and De Law (1930), Hurston's edition of the collaboration work, could be the truly first attempt in the tradition of American black folk comedy. By illuminating a series of historical moments in which Hurston first expressed her dream for writing a real black folk comedy that would be a really new departure in the African American drama, then collaborated with Hughes on the dream play project, and eventually quit the collaborationship due to artistic dispute with Hughes, this paper explains why Hughes edition Mule Bone came to remain 'unfinished' and, more importantly, fall short of Hurston's original goal and expectation from the collaboration. On the other hand, this paper sheds light on the significance of often-ignored Hurston's edition De Turkey and De Law by demonstrating how this play, compared to Mule Bone, fulfills her original idea of black folk comedy in terms of contents and themes compared with Mule Bone. Adding to the knowledge about little known behind story related to the Mule Bone controversy and the subsequent birth of the two different editions of the Hurston-Hushes collaboration project, supplementing the dearth of the related research with a critical comparison of the two editions, and discussing the validity of Hurston's edition as the real sense of black folk comedy, this paper argues for the necessity of reconsidering the origin of the mentioned genre. This paper finally concludes that De Turkey and De Law, replacing Mule Bone, deserves a right to be truly the first American black folk comedy genre in the sense that it was completed and copyrighted three months earlier than Mule Bone and that, more importantly, it cherished the original aim and artistic vision of black folk comedy Hurston first planned and expected through the collaboration with Hughes.

• Geomechanics and Engineering
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• v.35 no.6
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• pp.603-615
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• 2023

Population growth and urbanization prompted engineers to propose more sophisticated and efficient transportation methods, such as underground transit systems. However, due to limited urban space, it is necessary to construct these tunnels in close proximity to existing infrastructure like high-rise buildings and bridges. Battered piles have been widely used for their higher stiffness and bearing capacity compared to vertical piles, making them effective in resisting lateral loads from winds, soil pressures, and impacts. Considerable prior research has been concerned with understanding the vertical pile response to tunnel excavation. However, the three-dimensional effects of tunnelling on adjacent battered piled foundations are still not investigated. This study investigates the response of a single battered pile to tunnelling at three critical depths along the pile: near the pile shaft (S), next to the pile (T), and below the pile toe (B). An advanced hypoplastic model capable of capturing small strain stiffness is used to simulate clay behaviour. The computed results reveal that settlement and load transfer mechanisms along the battered pile, resulting from tunnelling, depend significantly on the tunnel's location relative the length of the pile. The largest settlement of the battered pile occurs in the case of T. Conversely, the greatest pile head deflection is caused by tunnelling near the pile shaft. The battered pile experiences "dragload" due to negative skin friction mobilization resulting from tunnel excavation in the case of S. The battered pile is susceptible to induced bending moments when tunnelling occurs near the pile shaft S whereas the magnitude of induced bending moment is minimal in the case of B.

• Ocean Systems Engineering
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• v.14 no.2
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• pp.171-210
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• 2024

This paper focuses on the rigorous and holistic fatigue analysis of mooring chains for a deep draft semi-submersible platform in the challenging environment of the central Gulf of Mexico (GoM). Known for severe hurricanes and strong loop/eddy currents, this region significantly impacts offshore structures and their mooring systems, necessitating robust designs capable of withstanding extreme wind, wave and current conditions. Wave scatter and current bin diagrams are utilized to assess the probabilistic distribution of waves and currents, crucial for calculating mooring chain fatigue. The study evaluates the effects of Vortex Induced Motion (VIM), Out-of-Plane-Bending (OPB), and In-Plane-Bending (IPB) on mooring fatigue, alongside extreme single events such as 100-year hurricanes and loop/eddy currents including ramp-up and ramp-down phases, to ensure resilient mooring design. A detailed case study of a deep draft semi-submersible platform with 16 semi-taut moorings in 2,500 meters of water depth in the central GoM provides insights into the relative contributions of wave scatter diagram, VIMs from current bin diagram, the combined stresses of OPB/IPB/TT and extreme single events. By comparing these factors, the study aims to enhance understanding and optimize mooring system design for safety, reliability, and cost-effectiveness in offshore operations within the central GoM. The paper addresses a research gap by proposing a holistic approach that integrates findings from various contributions to advance current practices in mooring design. It presents a comprehensive framework for fatigue analysis and design optimization of mooring systems in the central GoM, emphasizing the critical importance of considering environmental conditions, OPB/IPB moments, and extreme single events to ensure the safety and reliability of mooring systems for offshore platforms.

• Sijohaknonchong
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• v.42
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• pp.117-150
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• 2015

English sijo is the sijo poems written in English. This paper considered English sijo especially in association with its wit. In English-speaking countries, wit has been often emphasized as one of the main characteristics of the sijo genre, and it is often found in many English sijo poems. As a critical term, wit indicates a kind of "concord of discord", which consists of dissimilar images, paradox, irony, etc. This paper investigated how English sijo embodied this kind of critical wit and created three kinds of delight; those are intelligent, sarcastic, and humorous one. First, I examined old Korean sijo poems and the wit embedded in them, and then I compared them to the case of English sijo. Sijo was received in English-speaking countries in the context of the literary genre tradition such as the epigram and the sonnet, and of the literary concepts such as irony and wit. In this context, sijo, which has a three-divided semantic structure and a twist in the last part, often containing irony and wit, could be received and composed without much difficulty in Englih-speaking countries. Many English sijo poems contain wit, and they make abundant delight, which is intelligent, sarcastic, or humorous. Wit is found in Korean old sijo too, but the wit that catches humorous moments variously in everyday lives, rather than show acid sarcasm or exaggerated comic scene, is a remarkable characteristic of the English sijo. English sijo presents the possibility of the sijo genre as the poetry of everyday life, which presents various aspects of daily lives in a warm and delightful perspective.

• Korean Journal of Applied Biomechanics
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• v.25 no.2
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• pp.191-198
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• 2015

Objective : The purpose of this study was to conduct biomechanical analysis of varying backpack loads on the lower limb movements during downhill walking over $-20^{\circ}$ ramp. Method : Thirteen male university students (age: $23.5{\pm}2.1yrs$, height: $175.7{\pm}4.6cm$, weight: $651.9{\pm}55.5N$) who have no musculoskeletal disorder were recruited as the subjects. Each subject walked over $20^{\circ}$ ramp with four different backpack weights (0%, 10%, 20% and 30% of body weight) in random order at a speed of $1.0{\pm}0.1m/s$. Five digital camcorders and two force plates were used to obtain 3-d data and kinetics of the lower extremity. For each trial being analyzed, five critical instants were identified from the video recordings. Ground reaction force, loading rate, decay rate, and resultant joint moment of the ankle and the knee were determined by the inverse dynamics analysis. For each dependent variable, one-way ANOVA with repeated measures was used to determine whether there were significant differences among four different backpack weight conditions (p<.05). When a significant difference was found, post hoc analyses were performed using the contrast procedure. Results : The results of this study showed that the medio-lateral GRFs at RHC in 20% and 30% body weight were significantly greater than the corresponding value in 0% of body weight. A consistent increase in the vertical GRFs as backpack loads increased was observed. The valgus joint movement of the knee at RTO in 30% body weight was significantly greater than the corresponding values in 0% and 10% body weight. The increased valgus moment of 30% body weight observed in this phase was associated with decelerating and stabilizing effects on the knee joint. The results also showed that the extension and valgus joint moments of the knee were systematically affected by the backpack load during downhill walking. Conclusion : Since downhill walking while carrying heavy external loads in a backpack may lead to excessive knee joint moment, damage can occur to the joint structures such as joint capsule and ligaments. Therefore, excessive repetitions of downhill walking should be avoided if the lower extremity is subjected to abnormally high levels of load over an extended period of time.

• Journal of Korean Society of Steel Construction
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• v.19 no.6
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• pp.611-620
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• 2007

The beam-column connection is the critical design section of general steel frame structures owing to the behavioral characteristics of the structural system. As most members of a frame structure are composed of rolled section beams, the cross-section of the beam members is governed by the negative bending moment near beam-column connections. Such a design concept leaves a redundant load-carrying capacity at the positive bending regions of the beam members leading to design inefficiency. Therefore, it is of utmost importance to redistribute the beam end moments and reduce the stresses at the beam-column connections for a more efficient design of steel frame structures. In this study, reaction-moment prestressing method (RMPM) was proposed for the innovative design and construction of steel frame structures. The RMPM is a prestressing method utilizing the elastic bending deformation of a beam member induced by temporary prestressing for the distribution of a relatively large bending moment to other sections for the efficient use of the beam section. By the application of the RMPM, the negative bending moment at the beam-column connections can be significantly reduced, ultimately leading to possible use of smaller beam sections. Through a series of model tests and numerical analyses of steel frame structures, the moment distributing effect and feasibility of the RMPM was verified.

• Strategy21
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• s.46
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• pp.205-238
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• 2020

The origin of mission command can be traced to the era of the Prussian military reforms led by General Gerhard von Scharnhorst after defeats in battle of Jena and Auerstadt in 1806 against Napoleon I. Mission Command is the conduct of military operations through decentralized execution based upon mission-type orders. Commanders issue mission-type orders focused on the purpose of the operation rather than details of how to perform assigned tasks. The mission command has become the command philosophy of the German military and recently many countries in the west accept it as a command philosophy. This study compare and analyze the Battle of St. Vincent and the Battle of Jutland to make sure if the army-initiated mission commands were also useful for the navy. From the late 18th century, represented by the era of Nelson, Royal navy changed from the inherited rigid command culture to guaranteeing the disciplined initiative of its subordinate commanders. In the Battle of St. Vincent in 1797, Nelson acted contrary to the commander's orders at the crucial moment, which gave Britain a decisive victory. On the contrary more than 100 years later, the command culture of the Royal navy changed into a centralized command culture. In the Battle of Jutland in 1916, Royal Navy couldn't win because the rigid command culture did not guarantee initiative of subordinate commanders and subordinate commander's passive attitude of waiting for the commander's instructions even at critical moments. Therefore, a mission command that guarantees the initiative of subordinate commanders is a useful concept even in the navy because it makes subordinate commanders to take full advantage of a sudden change in battle. Today's advanced information and communication technologies have raised questions about mission command. But even advanced technology can't completely eliminate the fundamental nature of the war-the fog of war. War is chaotic and unpredictable. In the flood of lots of informations, senior commander's judgement is not always right because he(she) is also human, he(she) can make mistakes. In the age of informatization, mission command is still effective because it involves increasing interaction and synergy between senior and subordinate commanders by ensuring their independence. Therefore ROK navy also needs to activate mission command. ROK navy must dismantle the zero-defect mentality and apply from educations as Prussian did to establish a mission command culture.

• Spatial Information Research
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• v.22 no.5
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• pp.43-52
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• 2014

Recently, Big Data is a buzzword in the creative economy generation. The organizations related to spatial information society focus on building the spatial big data systems. As spatial big data is a combination of spatial information and big data, the data visualization is essential in order to utilize them efficiently. One of the great methodologies for data visualization is infographics. Nationally, Chousn.com initiated the infographics news in 2010. Korean Administration Branches also recognized the importance of infographic and they adopted infographics for their briefings from 2013. Internationally, Visual.ly is leading company in the infographics market and they produced noticeable interactive infographics for Egypt Parliamentary Elections results. In the defense part, Guardian's datajournalism of Afghanistan war log was a good example of utilizing infographics. Throughout the research, five requirements are extracted. First source data should have precision and accuracy in terms of time and space manner. Second, infographics images have a compressibility. Third, the infographics is properly processed for military commanders. Fourth, sharing, openness and communication are essential for high quality infographic. Lastly, infographics should be an analytic tool for predicting future event based on the past data. Infographics is not a direct representation of data but an analytic tool for helping user's choice and decision in critical moments.

• Cross-Cultural Studies
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• v.41
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• pp.381-413
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• 2015

This article aims to trace a historical trajectory of "Humanism" as a Modern scientific concept in the light of Michel Foucault's genealogy. Generally, we believe that Humanism is a natural and eternal idea for mankind, because no one doubts that he or she is not included in the category of a "Human Being." On the contrary, according to French philosopher Foucault, the Idea of Humanism, or anthropocentrism, appeared only in the Modern Age, from the 16th century downward. Before the Renaissance, human beings did not occupy the most important status in Nature, and only existed as natural beings. As soon as mankind was liberated from the superstitious of fear and religious dogma, the concept of "Human Being" is supplied with new meanings and values. The famous maxim, such as, "Man is the lord of creation" constitutes modern human science as an inviolable category of modernity. However, Foucault tried to illuminate the hidden sides of humanism, and gave us the strict warning on the end of the human beings, which turned out to be an object of Modern knowledge. If there would be no reason to maintain a knowledge system of Modernity, in other words, Modernity as knowledge would lose its validity and we could give up Humanism as a heavy burden. Moreover, it is very clear that we are confronted with the critical moments of radical skepticism on the meaning and value for Humanity. That means that we need to think about the new transformations of Human Beings, which will probably appear in the forms of "Non-Humans," "Machines (Deleuze & Guattari)," or "Post-Humans" etc. At the present time, we cannot know if it will be positive, or negative for mankind. We should look back at the history of Humanism from a genealogical perspective, which is why we have to investigate the conceptual trajectory of Humanism in this moment.