• Journal of Ocean Engineering and Technology
• /
• v.25 no.2
• /
• pp.120-126
• /
• 2011

The fatigue damages in structural details of offshore plants can be accumulated due to various environmental loadings such as swell, wave, wind and current. It is known that load histories acting on mooring and riser systems show stationary and ergodic bimodal wide-banded process. This paper provides refined approach to obtain time signals representing stress range histories from wide-banded bimodal spectrum which consists of ideally narrow-banded and fully separated two spectrums. Variations of the probabilistic characteristics for time signals according to frequency and sampling time increments are compared with the reference data to be the probabilistic characteristics such as zero-crossing period, peak period, and irregularity factor obtained from an assumed ideal spectrum. It is proved that the sampling time increment more affects on the probabilistic characteristics than frequency increment. The fatigue damages according to the frequency and sampling time increments are also compared with the ones with minimum increment condition which are thought to be exact fatigue damage. It is concluded that the maximum sampling time increment to obtain reliable time signals should be determined that ratio of applied maximum sampling time increment and minimum period is less than approximately 0.08.

• Archives of Craniofacial Surgery
• /
• v.14 no.2
• /
• pp.119-123
• /
• 2013

Except for special situations, it is generally agreed that best results in the treatment of facial fractures is expected if reduction is done within the first 2 or 3 weeks after injury. We reduced facial bone fractures at 4 to 7 weeks after trauma. A 44-year-old female patient underwent open reduction for her right zygomaticomaxillary complex fracture at 7 weeks after injury. A 59-year-old female patient underwent surgery for the right mandible body and left parasymphysis fractures at 4 weeks after injury. Using traditional approaches, granulation tissue and callus were removed from the fracture sites, and malunited fracture lines were separated by a small osteotome. We reduced the displaced fractured zygoma and mandible to their normal anatomical positions and fixed them using titanium plates. No complications such as asymmetry, malunion, malocclusion, or trismus were seen. Unfavorable asymmetric facial contours were corrected, and we obtained good occlusion with favorable bony alignment. The functional and aesthetic outcomes were satisfactory. Through removal the callus and limited osteotomy, a successful approach to the previously fractured line was possible, and an exact correction with symmetry was obtained. This method can be a good option for obtaining good mobility and clinical results in treating delayed facial bone fractures.

• Journal of the Korea Institute of Building Construction
• /
• v.15 no.1
• /
• pp.99-105
• /
• 2015

The building structure has an decisive influence on the environment as it takes over one third part in the energy consumption and greenhouse gas emissions of whole world. Accordingly, every country makes the reduction of greenhouse gas emission compulsory pursuant to Kyoto Protocol of 1997, and Korea government makes an announcement for the improvement of building energy performance in 2014. In this study, the key technology of Energy Saving Environmental-Friendly Building is sorted into 3rd categories, and the analysis of patent trend for patent documents published in Korea, USA, Japan and Europe is carried out. The purpose of this study is to solve the problem of current technology that it cannot show the detailed situation of technique and development strategy of R&D, and to provide a systematic approach for R&D strategy and an exact technology development direction.

• Journal of Korea Society of Industrial Information Systems
• /
• v.17 no.4
• /
• pp.61-70
• /
• 2012

We propose a method that finds candidate targets based on morphology and detects a small target from them using modified gaussian distance function. The existing small target detection methods use predictive filters or morphology. The methods using predictive filters take long to approach least errors. The methods using morphology are weak at clutters and need to consider size of a small target when selecting size of structure elements. We propose a robust method for small target detection to complete the existing methods. First, the proposed method deletes clutters using a median filter. Next, it does closing and opening operation using various size of structure elements, and figures target candidate pixels with subtraction operation between the results of closing and opening operation. It detects an exact small target using a gaussian distance function from the candidates target areas. The proposed method is less sensitive to clutters, and shows a detection rate of 98%.

• Biomolecules & Therapeutics
• /
• v.24 no.3
• /
• pp.207-243
• /
• 2016

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by social and communication impairments, as well as repetitive and restrictive behaviors. The phenotypic heterogeneity of ASD has made it overwhelmingly difficult to determine the exact etiology and pathophysiology underlying the core symptoms, which are often accompanied by comorbidities such as hyperactivity, seizures, and sensorimotor abnormalities. To our benefit, the advent of animal models has allowed us to assess and test diverse risk factors of ASD, both genetic and environmental, and measure their contribution to the manifestation of autistic symptoms. At a broader scale, rodent models have helped consolidate molecular pathways and unify the neurophysiological mechanisms underlying each one of the various etiologies. This approach will potentially enable the stratification of ASD into clinical, molecular, and neurophenotypic subgroups, further proving their translational utility. It is henceforth paramount to establish a common ground of mechanistic theories from complementing results in preclinical research. In this review, we cluster the ASD animal models into lesion and genetic models and further classify them based on the corresponding environmental, epigenetic and genetic factors. Finally, we summarize the symptoms and neuropathological highlights for each model and make critical comparisons that elucidate their clinical and neurobiological relevance.

• The Journal of Art Theory & Practice
• /
• no.1
• /
• pp.7-22
• /
• 2003

What is 'Art Theory'? In the western sense, the term poses a vague ambiguity, and in the eastern, it is rather an abstract and metaphysical concept. As for etymology, theory is derived from theoria and theoria from theoros. It refers to an act of viewing or seeing, of course not in a metaphysical sense. Plato understood it as 'eide'. During the time of Plotinus, theoria encompassed gazing at every possible reality, and this gazing, that is theoria, is closely related to reality as aunit that theoriacan perceive. However, we tend to distinguish, as other scientists of dualism have done, studio art from theory since a pre-modern approach to art has been particularly tuned to studio practice, set apart from theory. Therefore, in studio classes, students are expected to learn the subject based on the foundational curriculum methods such as medium, genre, technique:, rather than bringing out their own interpretations and discussing theories. As a result, students have become artists, who are not able to understand their own art. Art professors who conduct class in studio are required to proceed with specific 'theories' as well as 'intellectual reflections'. In this respect, this thesis presents poiesis and an idea of 'acting out'. Although art history and aesthetic theory tend to view art as a finished product, actual art-making and related theories should not only be acknowledged as 'completion' (finition) but also be accompanied by theoretic interpretations of the act itself and process. Accordingly, it is to accept and appreciate art as finished result in view of current theory and aesthetics thus boils down to aisthesis. Likewise, poietics starts from a point where an artist is related to studio and examines the 'work process' that extends as far as to the exact end of work. Through the study of such relationship, it is possible that theory understands 'studio' and 'process', and an artist can grant an independent meaning to studio where s/he pours her/his heart out creating a work of art. Theory is a study on artistic discovery thus should be equipped with functions that can accommodate fortuity, imitation, thinking, culture, and surrounding.

• The Transactions of the Korea Information Processing Society
• /
• v.3 no.7
• /
• pp.1753-1762
• /
• 1996

Since the number of spatial objects go easily into millions, they are stored on a secondary storage. In order to speed up accessing the geometric objects, we investigate spatial database system. The spatial objects are organized and accessed by spatial access methods(SAMs). But, SAMs are not able to organize polygons directly The most popular approach for handing polygon in SAMs is to use MBR apporximaotion as a geometric key. MBR provides a fast but inaccurate answers to approximation-based query processing. The performance of approximation-based spatial query processing depends on which type of approximation is chosen for the spatial objects. A suitable approximation is crucial for reducing the size of the candidate set. The better the approxmation quality, the fewer accesses to the exact object are necessary. In this paper, I proposed a new multicontainer approximation named Slice decomposition. The performance of proposed method is compared with other method.

• Journal of Korean Institute of Industrial Engineers
• /
• v.26 no.1
• /
• pp.73-80
• /
• 2000

To determine the exact direction and location of the human joint in motion is crucial in developing a more accurate human model and producing a more fitting artificial joint. There have been several reports on the biomechanical analysis of the joint to determine the anatomy and movement of joints. However, all the previous researches were made in vitro study, that is, they investigated the passive movement of the joint from cadavers and the suggested location of the joint axis was difficult to make practical applications due to the lack of the direction of joint axis. Also, in many biomechanical models, each joint axis is assumed to lie horizontally or vertically to the adjacent links. Such an assumption causes inherent inaccuracy. In this study, the direction and location of the transverse elbow axis was obtained with respect to the global coordinate system whose origin is on the lateral epicondyle of the humerus. The suggested result based on the global coordinate system lying on the external landmark will be helpful to understand the information of the axis and to make an application. From the experiments conducted for five subjects, the direction and location of the elbow transverse joint was determined for each subject by the helical axis method. A statistical validation was also performed to confirm the result. Finally, the result was applied to develop a simple elbow model which is a part of the kinematic arm model. The simple elbow movement model was developed to validate the significance of the result and the kinematic arm model was able to describe the geometry of any complex linkage system. As a result, the errors incurred from the proposed model were significantly reduced when compared to the ones from the previous approach.

• The KIPS Transactions:PartD
• /
• v.9D no.5
• /
• pp.779-788
• /
• 2002

There are many technically difficult issues in searching multimedia data such as image, video and audio because they are massive and more complex than simple text-based data. As a method of searching multimedia data, a similarity retrieval has been studied to retrieve automatically basic features of multimedia data and to make a search among data with retrieved features because exact match is not adaptable to a matrix of features of multimedia. In this paper, data clustering and its indexing are proposed as a speedy similarity-retrieval method of multimedia data. This approach clusters similar images on adjacent disk cylinders and then builds Indexes to access the clusters. To minimize the search cost, the hashing is adapted to index cluster. In addition, to reduce I/O time, the proposed searching takes just one I/O to look up the location of the cluster containing similar object and one sequential file I/O to read in this cluster. The proposed schema solves the problem of multi-dimension by using clustering and its indexing and has higher search efficiency than the content-based image retrieval that uses only clustering or indexing structure.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.10 no.4
• /
• pp.25-33
• /
• 1990

The moment distribution method has been widely used for almost sixty years as an approximate method for the analysis of structural frames. The method is to calculate the end moments of structural members by iterative hand calculation. This study presents developements of closed form formulas which are derived basically from the moment distribution procedures. These formulas may provide simple forms and exact results which would overcome the disadvantages of the conventional moment distribution mothod, that is, approximation of the results and complexity of the procedures of the method. The proposed formulas may become one of the new procedures for analysis of statically indeterminate frames, and contribute specifically to the effective drawing of influence lines of continuous beams, which will provide a great deal of assistance in practical design of structures.