• Nuclear Engineering and Technology
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• 제53권1호
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• pp.199-207
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• 2021

This paper deals with accurate image reconstruction of gamma camera using a coded-aperture mask based on pixel-type CsI(Tl) scintillator coupled with silicon photomultipliers (SiPMs) array. Coded-aperture imaging (CAI) system typically has a smaller effective viewing angle than Compton camera. Thus, if the position of the gamma source to be searched is out of the fully-coded field-of-view (FCFOV) region of the CAI system, artifacts can be generated when the image is reconstructed by using the conventional cross-correlation (CC) method. In this work, we propose an effective method for more accurate reconstruction in CAI considering the source distribution of partially-coded field-of-view (PCFOV) in the reconstruction in attempt to overcome this drawback. We employed an iterative algorithm based on compressed-sensing (CS) and compared the reconstruction quality with that of the CC algorithm. Both algorithms were implemented and performed a systematic Monte Carlo simulation to demonstrate the possiblilty of the proposed method. The reconstructed image qualities were quantitatively evaluated in sense of the root mean square error (RMSE) and the peak signal-to-noise ratio (PSNR). Our simulation results indicate that the proposed method provides more accurate location information of the simulated gamma source than the CC-based method.

• 한국운동역학회지
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• 제28권4호
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• pp.219-225
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• 2018

Objective: Epidemiological research shows that 47 to 73% of athletes suffer from recurrent ankle sprains. Joint mobilization techniques (JMT) implemented in correcting may be beneficial in the management of ankle injuries. The purpose of this study is to examine the immediate JM on ankle complex as clinical measures in individuals with chronic ankle instability (CAI) through intervention. Method: Thirteen subjects with CAI (8 males and 5 females) participated in this study. Each subject tried total four alignments (Navicular drop test: NDT, Standing rearfoot angle: SRA, Tibia torsion: TT, and dorsiflexion range of motion: DFROM). The participants were performed the 10 meter shuttle run after JMT for post-task. Finally, it was tried to compare between pre-post tasks after shuttle run. Results: SRA and DFROM after intervention showed significant differences. SRA (p=.026), and DFROM (p=.034). Conclusion: We concluded that the JMT has resulted in improvement in SRA, DFROM. Increased DFROM and varus shapes of foot would be closed kinetic chain, indicating that reduce the risk factors of ankle sprain. Future study needs to be conducted in order to measure the effects of prolonged intervention of JMT.

• 건축역사연구
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• 제31권3호
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• pp.7-16
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• 2022

Fen(分°) is the proportional dimension unit of the standard timber section on Yingzaofashi(營造法式), and there is a phrase that not only structural members but the whole structural design of a building also use Fen as the dimension unit on the book. But in fact only the section dimensions of structural members are recorded by Fen, but the design dimensions are recorded by Chi(尺) on the book. Other historical records also described the building size by Chi. So there has been long-standing debate on the phase in Chinese architectural history society, including the recent confrontation on the analysis of survey figures of the east great hall of Foguangsi temple(佛光寺 東大殿). This paper analyzes all the records about the size of structural members and section planning on the book to make various calculation and evaluation. And it makes a survey of Cai(材) as the dimension and design unit between Chi and Fen through geometric analysis. Cai might be a rough unit of measurement in terms of structural and proportional scheming on Yingzaofashi, and the full size Cai(足材) had been a building scheming module before the Song dynasty.

• 한국콘텐츠학회논문지
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• 제5권4호
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• pp.78-84
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• 2005

방사선 유방영상에 있어서 교육용 프로그램을 사용하여 의료방사선 영상 교육시스템의 개발이 요구된다. 따라서 웹 기반으로 한 멀티미디어 저작도구를 사용하여 의료방사선기술의 유방영상획득 기법을 CAI 시스템으로 구현하고자 한다. 웹에서 신규 방사선사들이 시간과 공간을 초월한 원격교육을 받을 수 있으며, 학습자가 스스로의 관심과 의사에 따라 주관적인 지식을 형성 할 수 있도록 학습 환경을 제공하고, 다양한 매체들을 프로그램 속에 포함시작 학습효과를 증진시키고자 하였다. 객관적인 데이터에 근거해서 학습을 수행하기 때문에 잘못된 유방촬영기법을 학습하게 될 소지가 없다. 또한 저작도구에서 제공되는 하이퍼미디어 방식을 사용하였기 때문에 방사선사의 주관적인 의사에 따라 자유로운 학습이 가능하여 학습에 대한 보다 높은 관심과 학습효과를 가져올 수 있다. 본 연구에서 제안한 유방 방사선영상 촬영 교육용 시스템은 신규 방사선사의 교육을 목적으로 할 뿐 아니라 기존의 방사선사들에게도 도움을 줄 수 있으며, 변화하는 지식에 대한 계속적인 수용이 있을 것이며, 이를 기반으로 하여 다른 여러 촬영 방법에도 적용하여야 임상 방사선사들에게 유용한 프로그램으로 자리 잡게 될 것이다.

• 한국치위생학회지
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• 제14권3호
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• pp.417-424
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• 2014

Objectives : The purpose of the study is to develop and to evaluate the oral health education program using computer assisted instruction(CAI) for the elementary school students. This study was carried out from November, 2012 to February, 2013. Methods : The subjects were 188 elementary school students of the first, second, and third grades in Buk-gu, Busan. The education was provided as computer assisted instruction and conventional classroom education. Three trained dental hygienists recorded three times of knowledge of oral health, oral health attitude, oral health behaviors and the plaque control index(O'Leary index). Results : CAI group showed high score of oral health knowledge of 6.74 points, 8.62 points and 8.38 points(p<0.01). In oral health attitude, the scores were 7.40 points, 8.01 points, and 7.99 points(p<0.05). In oral health behavior, the scores were 5.47 points, 6.14 points, and 5.61 points(p<0.05). The plaque control index was 22.59 points, 19.69 points, and 21.44 points(p<0.01). Conclusions : CAI education program of this study showed the effective education for the elementary school students. So the CAI education program can be useful and disseminated to the community project.

• 한국전문물리치료학회지
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• 제28권3호
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• pp.200-207
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• 2021

Background: Postural control deficit is a major characteristic in patients with chronic ankle instability (CAI). Elastic ankle tapings are commonly used to facilitate postural control in patients with CAI as well as prevent relapse of a lateral ankle sprain. However, equivocal evidence exists concerning the effect of elastic ankle taping on postural control. Objects: This study aimed to evaluate the effects of elastic ankle tapings using kinesio taping (KT) and dynamic taping (DT) on static and dynamic postural control in patients with CAI. Methods: Fifteen subjects with CAI were participated in this study. The participants performed tests under three conditions (barefoot, KT, and DT). Static postural control was evaluated using the one-leg standing test (OLST) and dynamic postural control using the modified Star Excursion Balance Test (mSEBT). One-way repeated-measures analysis of variance was used to compare center of pressure (CoP) data and normalized mSEBT reach distances among the three conditions (with α = 0.05). Results: The CoP parameters (path length, ellipse area, and mean velocity) of the OLST significantly decreased on applying KT and DT compared with those when barefoot. The normalized reach distances in the anteromedial (AM), medial (M), and posteromedial (PM) directions of the mSEBT significantly increased with DT compared to that in the control condition. Further, the higher reach distances with KT compared with those in the control condition were obtained in the M and PM directions of the mSEBT. No significant differences were identified in any of the OLST and SEBT parameters between the two different taping applications. Conclusion: KT and DT improved static postural control during the OLST compared with the control condition. Moreover, these tapes improved dynamic postural control during the mSEBT compared to the control. Therefore, elastic ankle tapings are useful prophylactic devices for the prevention and treatment of ankle sprain in people with CAI.

• 한국전문물리치료학회지
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• 제31권2호
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• pp.151-158
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• 2024

Background: In Taekwondo athletes, ankle sprain is the most common risk factor for injury. Repeated ankle injuries lead to weakness and imbalance of the ankle muscles, resulting in chronic ankle instability (CAI). Both the ankle and toe muscles contribute to the inversion and eversion of the foot at the subtalar joint. Therefore, it is necessary to consider the ankle and toe joint positions when measuring ankle invertor and evertor strength. Objects: This study aimed to compare the muscle strength and ratio differences of the ankle invertor and evertor muscles in both the toe and ankle positions between the CAI and uninjured sides in Taekwondo athletes. Methods: Fifteen Taekwondo athletes participated in this study. The isometric strengths of both the ankle invertor and evertor were determined in different ankle and toe positions (dorsiflexion with toe extension, dorsiflexion with toe flexion, plantarflexion with toe extension, and plantarflexion with toe flexion). Paired t-tests were used to determine the differences between the ankle invertor and evertor in strength and ratio according to toe and ankle positions between the ankle CAI side and the uninjured side. Results: The results demonstrated that ankle evertor strength significantly decreased in all ankle and toe positions on the CAI side (p < 0.05). In addition, significant differences were observed in the ratios of the ankle invertor and evertor strengths in the dorsiflexion with toe flexion, plantarflexion with toe extension, and plantarflexion with toe flexion positions (p < 0.05). Conclusion: The findings of this study suggest that athletes, trainers, and clinicians should consider ankle and toe positions when measuring invertor and evertor strength and develop ankle rehabilitation protocols for Taekwondo athletes with CAI.

• Journal of Mechanical Science and Technology
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• 제20권9호
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• pp.1449-1458
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• 2006

Controlled Auto-ignition (CAI) combustion processes can be broadly divided between a CAI process that is applied to four-cycle engines and a CAI process that is applied to two-cycle engines. The former process is generally referred to as Homogeneous Charge Compression Ignition (HCCI) combustion and the later process as Active Thermo-Atmosphere Combustion (ATAC) The region of stable engine operation differs greatly between these two processes, and it is thought that the elucidation of their differences and similarities could provide useful information for expanding the operation region of HCCI combustion. In this research, the same two-cycle engine was operated under both the ATAC and HCCI combustion processes to compare their respective combustion characteristics. The results indicated that the ignition timing was less likely to change in the ATAC process in relation to changes in the fuel octane number than it was in the HCCI combustion process.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.71-75
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• 2005

For the damage tolerance improvement of conventional laminated composites, stitching process have been utilized for providing through-thickness reinforcements. 2D preforms were stacked with S-2 glass plain weave and S-2 glass MWK (Multi-axial Warp Knit) L type. 3D preforms were fabricated using the stitching process. All composite samples were fabricated by RTM (Resin Transfer Molding) process. To examine the damage resistance performance the low speed drop weight impact test has been carried out. For the assessment of damage after the impact loading, specimens were examined by scanning image. CAI (Compressive After Impact) tests were also conducted to evaluate residual compressive strength. Compared with 2D composites, the damage area of 3D composites was reduced by 20-30% and the CAI strength showed 5-10% improvement.

• 정보교육학회논문지
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• 제2권1호
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• pp.138-161
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• 1998

This research addresses to establish a systematic approach to design a standard Hangul code system for educational purposes in development of CAI courseware using Korean, English, and Chinese characters, which requires data exchanges and database construction. In this paper, types of Korean alphabetic code systems already in use, their representational environments and consonant/vowel order have been studied and analysed. This paper presents the requirements that the hangul code system for educational purpose needs to obtain. First, it should be able to represent all contemporary as well as ancient Korean alphabets. Second, character elements should be separable. Third, consonant/vowel order should be determined to easily retrieve and exchange data. Lastly, the code should maintain compatibility with other national codes and provide uniqueness of user-defined character codes.