• Explosives and Blasting
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• v.42 no.3
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• pp.1-8
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• 2024

The pressure-time histories recorded from blast holes exhibit wide variability depending on the type of explosives used. However, these history curves can generally be divided into the rising and falling branches. This characteristic is valuable for defining the time history of explosion pressure in rock blast modeling. However, the explosion pressure function proposed by Jiang et al. has two shape parameters which are explicitly related to the rise time interval, but not to the fall time interval. Hence, this study derived two conversion relations that can exactly translate given rise and fall time intervals into the shape parameters. Then, the conversion relations were utilized to approximate other pressure functions with the Jiang's function. This allows for greater emphasis on the physically significant rise and fall times, rather than on the pressure function itself, in the context of rock blast modeling.

• Journal of the Korean Institute of Rural Architecture
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• v.13 no.4
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• pp.115-124
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• 2011

This study examines the process of urban formation in the city of Yanji. The analysis is done by the change of street pattern and major facility location in a timely manner by appling space syntax method. This research categorizes the pattern of the urban growth focused on two urban forms, street and major buildings, in the city and is offered of the meaning of the first value on interpretation of the urban growth in the city of Yanji. The result of the research are as follows. First, the period of the city transformation is divided into four stage; intuitive period, grid-iron formative period, consolidation period, and urban expansion period. Second, characteristics of each stage have been analyzed. At the first stage, the city started to frame along both buildings and streets which were placed without a plan. At the second stage, the city was planned and constructed into new grid-iron pattern ignoring existing context by Jananese colony. At the consolidation period, the road system expands from the city center toward suburban. At the last expansion period, the shape of the city has complicated its shape with complex road system. This study contributes to provide a basic analysis and data to investigate how the Yanji city has evolved over period of time. But further continuous research should be done for future urban development of the Yanji city.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.4
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• pp.391-399
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• 2012

Multipath remains a dominant source of ranging errors in GNSS (Global Navigation Satellite System). And it is generally considered undesirable in the context of GNSS, since the reception of multipath can make significant distortion to the shape of the correlation function. In this paper, therefore, the model of the distorted shape of the correlation function is formulated and a MBME (Model-Based Multipath Estimation) technique for GPS L1/L5 receivers is proposed in order to estimate the parameters of the indirect signal such as the amplitude and the delay. The MBME technique does not require the any hardware modifications and it can estimate the parameters for both the short and long-delay multipath. Especially, it would be the very effective technique for the short-delay multipath if the L5 signal is available. Finally, the feasibility of the proposed technique has been confirmed by simulation results.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.1
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• pp.48-52
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• 2005

In this paper, the spectral shape invariant real-time voice change method is proposed to change one's voice to mechanical voice. For this purpose, LPC analysis and synthesis is used to maintain the spectraum of voice and the pitch of synthesis speech can be changed freely. In the proposed method, gain matching method is applied to excitation signal generator to make the changed voice natural to hear. In order to evaluate the performance of the proposed method, voice change experiments were conducted. Experimental results showed that original speech signal is changed to the mechanical voice signal in which context of the speaker's voice is conveyed correctly in spite of drastic change of pitch. The system is implemented using TI TMS320C6711DSK board to verify the system runs in real time.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.332-335
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• 2014

Applying damping sheets or dampers (dynamic or mass) can reduce noise from vibrating structure as well as vibration. However, this approach requires increases of weight and cost. If one can reduce structural noise by only modifying the structural shape, which would be the best practice. It is natural that the noise characteristics change when the structure is modified, but the recent experiment on the sunroof frame showed that the modification of the frame beads results in change of the structural damping, so that the corresponding noise can be reduced. In this context, the reason why the structural damping and the related noise upon an impact excitation is changed is theoretically investigated. The change of dynamic and damping characteristics of the strip panels when their shapes are modified is experimentally found and it is shown that such behaviours can be predicted by computer simulation. Some experimental specimen, mainly strip-type panels, are examined for the numerical verification, and especially damping ratios are investigated.

• Journal of Korea Planning Association
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• v.54 no.3
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• pp.15-26
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• 2019

The development of science and transportation technology leads to the increase of inter - city networks that play an important role in urban growth. Overall, numerous studies based on network theory pay attention to positive effects of urban network on urban growth. However, some studies have pointed out the negative effects of inter-city interactions such as straw effects. This implies that the network between cities may not be positively correlated with urban growth, and that the direction of the influence may vary from a certain threshold, such as the marginal utility curve. In this context, the purpose of this study is to measure the impacts of network with central city on urban growth in the capital region and examine the relationship between urban network and growth. Two multiple regression models are employed with changes in population and employment as dependent variables. The urban network index and other control variables are used as independent variables. Especially, the urban network indexes are used in quadratic forms to examine non linear relations with urban growth such U-shape or an inverted U-shape. The results show that the relationships between networks with the central city and urban growth are not a simple linear, and the influence can be changed from the critical point.

• Archives of Plastic Surgery
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• v.49 no.3
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• pp.453-456
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• 2022

When the scrotal sac is entirely debrided following a Fournier gangrene, testes exposure poses unique challenges for the reconstructive surgeon. Despite the anterolateral thigh (ALT) flap is considered a workhorse in such context, aesthetic results are often suboptimal because of the lack of natural ptosis and patchwork appearance. We describe the use of a super-thin pedicled ALT flap for total scrotal reconstruction, modified according to a peculiar flap design and inset technique. A 42-year-old man was referred to our department for delayed total scrotal reconstruction 8 months after a Fournier gangrene extensive debridement. A super-thin pedicled ALT flap from the right thigh was designed: in the central portion of the ALT, a lateral skin paddle extension was marked to guarantee adequate posterior anchorage during insetting and ptosis of the scrotal sac. This particular flap arrangement has inspired the name "sombrero" as the shape is akin to the famous hat. No secondary refinements were needed, and the patient showed satisfying aesthetic and functional results at 12 months' follow-up. The ALT flap design "sombrero" modification proposed in this article can improve scrotum cosmesis and patient satisfaction in a single-stage single-flap procedure.

• Journal of Fashion Business
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• v.26 no.6
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• pp.14-31
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• 2022

Worn by both males and females the kimono is the national dress of Japan. Previous research highlights that this national dress is fading from tradition and evolves to develop with the times and fashion trends. This research aims to investigate what a kimono represents both historically and currently within Western society. The idea of the kimono being more than a national dress representing Japan, the main three themes researched will be (1) Shape (2) Narrative (3) Journey from East to West. Based on both primary and secondary sources this research indicates that there is a strong relationship between the universal increase of kimono wearers in Eastern and Western societies from history through to present day. Primary research is utilised in the form of two types of interviews. Primary outcomes bring a personal perspective to how and why kimono is worn nowadays within Europe. Secondary sources include online lectures held by kimono specialists as well as subject relevant books. From the 19th century where the Dutch were the only European country to trade with Japan, an exchange of fabrics took place which later led to the exchange of: fit, fashion and pattern (primarily within Western womenswear fashion.) This distinct garment never gets discontinued and evolves with social demands within society today.

• Steel and Composite Structures
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• v.44 no.5
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• pp.603-617
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• 2022

Structural design, in general, is developed through trial and error technique which is guided by standards criteria and based on the intuition and experience of the engineer, a context that leads to structural over-dimensioning, with uneconomic solutions. Aiming to find the optimal design, structural optimization methods have been developed to find a balance between cost, structural safety, and material performance. These methods have become a great opportunity in the steel structural engineering domain since they have as their main purpose is weight minimization, a factor directly correlated to the real cost of the structure. Assuming an objective function of minimum weight with stress and displacement constraints provided by Brazilian standards, the present research proposes the sizing optimization and combined approach of sizing and shape optimization, through a software developed to implement the Simulated Annealing metaheuristic algorithm. Therefore, two steel plane frame layouts, each admitting four typical truss geometries, were proposed in order to expose the difference between the optimal solutions. The assessment of the optimal solutions indicates a notable weight reduction, especially in sizing and shape optimization combination, in which the quantity of design variables is increased along with the search space, improving the efficiency of the optimal solutions achieved.

• Korean Institute of Interior Design Journal
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• v.16 no.2 s.61
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• pp.87-96
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• 2007

This study analyzes the place of modem architecture based on the place theory of C. N, Schultz. For applying Schultz's theory to the modern architecture, It is required to examine the modern cityscape, features of inner space of architecture and features of program. By analyzing the avant-garde architecture of Rem Koolhaas on such basis, the potentiality of placeness of modern architecture could be verified and the alternatives would be searched. It is inferred that the placeness features of Rem Koolhaas' public architecture is under the influence of the interpretation of program based on the humane background rather than the physical aspects of surroundings. The inner space shows the non-linear features, the metaphor of city. The obscurity of physical boundary illustrates the flexible features with ambiguous boundary. Consequently, the inner space expresses the surreal atmosphere that doesn't match the purposes of usage of architecture, the traditional concept. The outer shape is recognized as the by-product from the interpretation of internal program rather than it considered the surrounding context. The outer shape has the relatively simple formative shape and contrasts against the complicated inner space by using the non-physical materials. It is found that Koolhaas' architecture doesn't pursue the features of placeness of traditional concept. However, It is inferred that his architecture has the possibility of placeness by attaching the meaning through the social roles of each architecture. It gives the substantial suggestion to the modern architecture that can't easily acquire the placeness of traditional concept due to the environment of modern city.