• Title/Summary/Keyword: distortions

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Twisting Effect on Supermicroanastomosis of the Superficial Inferior Epigastric Artery in a Rat Model (혈관 비틀림이 백서 천층하복부 동맥의 초미세문합에 미치는 효과)

  • Seo, Mi-Hyun;Kim, Soung-Min;Eo, Mi-Young;Kang, Ji-Young;Myoung, Hoon;Lee, Jong-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.33 no.5
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    • pp.375-384
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    • 2011
  • Purpose: The advent of microsurgical technique and instruments, particularly in the field of perforator flap and supermicrosurgery, which have expanded the scope of microsurgery. However, supermicroanastomosis without any compression, tension, or distortions must be achieved to reach successful outcomes. Small-caliber vessels, such as those with an internal diameter less than 0.2 mm, are susceptible to inadvertent twisting of the anastomosis. In this study, using the superficial inferior epigastric artery (SIEA)-based flap model in Sprague-Dawley (SD) rats, we evaluated the acceptable limits of twisting effects on supermicroanastomotic sites. Methods: A total of 20 supermicroanastomoses were performed using the SIEA-based flap model in 10 male SD rats, 10-weeks-of-age, weighing 300~350 g. Rats were divided into five groups of two with four flaps as follows: 1) sham, 2) control group with end to end SIEA arterial supermicroanastomosis, 3) experimental I (EA1) with $90^{\circ}$ twisting, 4) experimental II (EA2) with $180^{\circ}$ twisting, and 5) experimental III (EA3) with $270^{\circ}$ twisting of the supermicroanastomosis. Each SIEA was anastomosed using six 11-0 $Ethilon^{(R)}$ (Ethicon Inc. Co., NJ, USA) stitches except in the sham group where the SIEA was only clamped with Supermicro vascular $clamps^{(R)}$ (S&T, Neuhausen, Switzerland) for 20 minutes. Results: The anastomosed arterial patency showed no remarkable changes according to doppler waveforms measured with a Smardop 45 Doppler System (Hadeco Inc., Kawasaki, Japan). The pulsatility index (PI) was increased at postoperative day 10 in the EA2 and EA3 groups, and the resistance index (RI) showed no statistically significant difference between preoperative and postoperative values at 10 days. Histologic specimens from the EA3 group showed increased tunica media necrosis, convolution of the internal elastic lamina, densely packed platelets, fibrin, and erythrocytes. Flap viability and anastomosed vessel patency were not significantly affected by the degree of arterial twisting in this study, other than in the EA3 group where minor effects on arterial patency of the microanastomoses were encountered. Conclusion: It appears that minor twisting on small caliber arteries, used in supermicroanastomoses, can be tolerated. However, twisting should be avoided as much as possible, and more than $180^{\circ}$ twisting must be prevented in clinical practice.

A Qualitative Study on Reducing Dental Anxiety through Cognitive Behavioral Therapy (인지행동치료를 통한 치과불안 감소에 대한 질적 연구)

  • Koh, Boo-Il;Song, Youn-Mi;Bae, Soo-Myoung
    • Journal of dental hygiene science
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    • v.17 no.1
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    • pp.46-55
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    • 2017
  • Many people in Korea suffer from a fear of dental treatments; however, only a few studies have focused on this population. This study assessed the effectiveness of cognitive behavioral therapy (CBT) and its interventions in reducing dental anxiety, especially when administered by trained dental staff. Using case studies, the authors analyzed the content of each session and examined the process of reducing dental anxiety. First, the authors observed that the results of both dental fear scale and subjective unit of disturbance decreased significantly with changes in cognitive distortions related to dental anxiety and that rapid improvements were noted after two therapy sessions. Second, the study reported that practicing relaxation (deep-breathing) and muscle relaxation techniques; using hand signals to indicate anxiety or discomfort; establishing an empathic relationship with the therapist; making an anxiety list; and graded insensitive and exposure along with rehearsal, were effective in coping with dental anxiety and in changing negative thoughts towards the dentist. Third, a simple cognitive behavioral intervention can be effective in reducing dental anxiety. In summary, a short-term, five-session psychological intervention with CBT produced a sustained decrease in the symptoms of dental anxiety, allowing the patients to receive the required procedures. The authors discussed the study limitations and the implication of their results on future research.

Analysis of Crustal Deformation on the Korea Peninsula after the 2011 Tohoku Earthquake (한반도 지각의 2011 도호쿠 대지진 영향 분석)

  • Kim, Su-Kyung;Bae, Tae-Suk
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.30 no.1
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    • pp.87-96
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    • 2012
  • The U.S. Geological Survey (USGS) announced that an earthquake of 9.0 magnitude had occurred near the east coast of Japan on March 11, 2011, resulting in a displacement of the crust of about 2.4 meters. The Korean peninsula is located on the Eurasian tectonic plate that stretches out to Japan; therefore, there is a high possibility of being affected by an earthquake. The Korean GPS CORS network operated by the National Geographic Information Institute (NGII) was processed for ten days before and after the earthquake. Both static and kinematic baseline processing were tested for the determination of crustal deformation. The static baseline processing was performed in two scenarios: 1) fixing three IGS stations in China, Mongolia and Russia; 2) fixing SUWN, one of the CORS networks in Korea, in order to effectively verify crustal deformation. All data processing was carried out using Bernese V5.0. The test results show that most of the parts of the Korean peninsula have moved to the east, ranging 1.2 to 5.6 cm, compared to the final solution of the day before the earthquake. The stations, such as DOKD and ULLE that are established on the islands closer to the epicenter, have clearly moved the largest amounts. Furthermore, the station CHJU, located on the southwestern part of Korea, presents relatively small changes. The relative positioning between CORS confirms the fact that there were internal distortions of the Korean peninsula to some extent. In addition, the 30-second interval kinematic processing of CORS data gives an indication of earthquake signals with some delays depending on the distance from the epicenter.

XRD and TEM Investigations of Structures and Phase Transformations in Albite (XRD와 TEM을 이용한 알바이트의 구조 및 상전이 연구)

  • 김윤중;이영부
    • Journal of the Mineralogical Society of Korea
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    • v.16 no.1
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    • pp.91-106
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    • 2003
  • XRD results on annealing studies of Na-feldspars (Amelia albite) show rapid changes in the lattice parameters of the $1073^{\circ}C$-heated samples owing to disordering of Al and Si as well as lattice distortions upon quenching of the heated specimens. While a low albite transformed to a high albite by 7-days annealing at $1073^{\circ}C$, it remains as an early intermediate albite even by 140-days annealing at $924^{\circ}C$ due to the slower Al-Si disordering rate. From the heated samples tweed structures of $100∼200\AA$ were typically observed by TEM, which showed different ways of development between the $1073^{\circ}C$ -heated one and the $923 ^{\circ}C$ -heated one. The former locally trans-farmed to rnicrostructures similar to albite twin, while the latter transformed to domain structures containing albite twin plane in the wider area. The origin of tweed structures is suggested to be formation of incipient twins (albite twin and pericline twin) to reduce the lattice instability which is increased by disordering of Al and Si as well as quenching.

The identification of Raman spectra by using linear intensity calibration (선형 강도 교정을 이용한 라만 스펙트럼 인식)

  • Park, Jun-Kyu;Baek, Sung-June;Park, Aaron
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.32-39
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    • 2018
  • Raman spectra exhibit differences in intensity depending on the measuring equipment and environmental conditions even for the same material. This restricts the pattern recognition approach of Raman spectroscopy and is an issue that must be solved for the sake of its practical application, so as to enable the reusability of the Raman database and interoperability between Raman devices. To this end, previous studies assumed the existence of a transfer function between the measurement devices to obtain a direct spectral correction. However, this method cannot cope with other conditions that cause various intensity distortions. Therefore, we propose a classification method using linear intensity calibration which can deal with various measurement conditions more flexibly. In order to evaluate the performance of the proposed method, a Raman library containing 14033 chemical substances was used for identification. Ten kinds of chemical Raman spectra measured using three different Raman spectroscopes were used as the experimental data. The experimental results show that the proposed method achieves 100% discrimination performance against the intensity-distorted spectra and shows a high correlation score for the identified material, thus making it a useful tool for the identification of chemical substances.

Automatic Left Ventricle Segmentation Algorithm using K-mean Clustering and Graph Searching on Cardiac MRI (K-평균 클러스터링과 그래프 탐색을 통한 심장 자기공명영상의 좌심실 자동분할 알고리즘)

  • Jo, Hyun-Wu;Lee, Hae-Yeoun
    • The KIPS Transactions:PartB
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    • v.18B no.2
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    • pp.57-66
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    • 2011
  • To prevent cardiac diseases, quantifying cardiac function is important in routine clinical practice by analyzing blood volume and ejection fraction. These works have been manually performed and hence it requires computational costs and varies depending on the operator. In this paper, an automatic left ventricle segmentation algorithm is presented to segment left ventricle on cardiac magnetic resonance images. After coil sensitivity of MRI images is compensated, a K-mean clustering scheme is applied to segment blood area. A graph searching scheme is employed to correct the segmentation error from coil distortions and noises. Using cardiac MRI images from 38 subjects, the presented algorithm is performed to calculate blood volume and ejection fraction and compared with those of manual contouring by experts and GE MASS software. Based on the results, the presented algorithm achieves the average accuracy of 6.2mL${\pm}$5.6, 2.9mL${\pm}$3.0 and 2.1%${\pm}$1.5 in diastolic phase, systolic phase and ejection fraction, respectively. Moreover, the presented algorithm minimizes user intervention rates which was critical to automatize algorithms in previous researches.

Comparisons of Color Spaces for Shadow Elimination (그림자 제거를 위한 색상 공간의 비교)

  • Lee, Gwang-Gook;Uzair, Muhammad;Yoon, Ja-Young;Kim, Jae-Jun;Kim, Whoi-Yul
    • Journal of Korea Multimedia Society
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    • v.11 no.5
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    • pp.610-622
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    • 2008
  • Moving object segmentation is an essential technique for various video surveillance applications. The result of moving object segmentation often contains shadow regions caused by the color difference of shadow pixels. Hence, moving object segmentation is usually followed by a shadow elimination process to remove the false detection results. The common assumption adopted in previous works is that, under the illumination variation, the value of chromaticity components are preserved while the value of intensity component is changed. Hence, color transforms which separates luminance component and chromaticity component are usually utilized to remove shadow pixels. In this paper, various color spaces (YCbCr, HSI, normalized rgb, Yxy, Lab, c1c2c3) are examined to find the most appropriate color space for shadow elimination. So far, there have been some research efforts to compare the influence of various color spaces for shadow elimination. However, previous efforts are somewhat insufficient to compare the color distortions under illumination change in diverse color spaces, since they used a specific shadow elimination scheme or different thresholds for different color spaces. In this paper, to relieve the limitations of previous works, (1) the amount of gradients in shadow boundaries drawn to uniform colored regions are examined only for chromaticity components to compare the color distortion under illumination change and (2) the accuracy of background subtraction are analyzed via RoC curves to compare different color spaces without the problem of threshold level selection. Through experiments on real video sequences, YCbCr and normalized rgb color spaces showed good results for shadow elimination among various color spaces used for the experiments.

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Face Recognition Robust to Local Distortion using Modified ICA Basis Images (개선된 ICA 기저영상을 이용한 국부적 왜곡에 강인한 얼굴인식)

  • Kim Jong-Sun;Yi June-Ho
    • Journal of KIISE:Software and Applications
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    • v.33 no.5
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    • pp.481-488
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    • 2006
  • The performance of face recognition methods using subspace projection is directly related to the characteristics of their basis images, especially in the cases of local distortion or partial occlusion. In order for a subspace projection method to be robust to local distortion and partial occlusion, the basis images generated by the method should exhibit a part-based local representation. We propose an effective part-based local representation method named locally salient ICA (LS-ICA) method for face recognition that is robust to local distortion and partial occlusion. The LS-ICA method only employs locally salient information from important facial parts in order to maximize the benefit of applying the idea of 'recognition by parts.' It creates part-based local basis images by imposing additional localization constraint in the process of computing ICA architecture I basis images. We have contrasted the LS-ICA method with other part-based representations such as LNMF (Localized Non-negative Matrix Factorization) and LFA (Local Feature Analysis). Experimental results show that the LS-ICA method performs better than PCA, ICA architecture I, ICA architectureII, LFA, and LNMF methods, especially in the cases of partial occlusions and local distortions.

Halotolerant Plant Growth Promoting Bacteria Mediated Salinity Stress Amelioration in Plants

  • Shin, Wansik;Siddikee, Md. Ashaduzzaman;Joe, Manoharan Melvin;Benson, Abitha;Kim, Kiyoon;Selvakumar, Gopal;Kang, Yeongyeong;Jeon, Seonyoung;Samaddar, Sandipan;Chatterjee, Poulami;Walitang, Denver;Chanratana, Mak;Sa, Tongmin
    • Korean Journal of Soil Science and Fertilizer
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    • v.49 no.4
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    • pp.355-367
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    • 2016
  • Soil salinization refers to the buildup of salts in soil to a level toxic to plants. The major factors that contribute to soil salinity are the quality, the amount and the type of irrigation water used. The presented review discusses the different sources and causes of soil salinity. The effect of soil salinity on biological processes of plants is also discussed in detail. This is followed by a debate on the influence of salt on the nutrient uptake and growth of plants. Salinity decreases the soil osmotic potential and hinders water uptake by the plants. Soil salinity affects the plants K uptake, which plays a critical role in plant metabolism due to the high concentration of soluble sodium ($Na^+$) ions. Visual symptoms that appear in the plants as a result of salinity include stunted plant growth, marginal leaf necrosis and fruit distortions. Different strategies to ameliorate salt stress globally include breeding of salt tolerant cultivars, irrigation to leach excessive salt to improve soil physical and chemical properties. As part of an ecofriendly means to alleviate salt stress and an increasing considerable attention on this area, the review then focuses on the different plant growth promoting bacteria (PGPB) mediated mechanisms with a special emphasis on ACC deaminase producing bacteria. The various strategies adopted by PGPB to alleviate various stresses in plants include the production of different osmolytes, stress related phytohormones and production of molecules related to stress signaling such as bacterial 1-aminocyclopropane-1-carboxylate (ACC) derivatives. The use of PGPB with ACC deaminase producing trait could be effective in promoting plant growth in agricultural areas affected by different stresses including salt stress. Finally, the review ends with a discussion on the various PGPB activities and the potentiality of facultative halophilic/halotolerant PGPB in alleviating salt stress.

Effects of Manual Intervention and Self-Corrective Exercise Models of the General Coordinative Manipulation on Balance Restoration of Spine and Extremities Joints

  • Moon, Sang Eun;Kim, Mi Hwa
    • Journal of International Academy of Physical Therapy Research
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    • v.4 no.2
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    • pp.573-587
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    • 2013
  • The purpose of this study was conducted in order to analyze the effects of the manual intervention and self-corrective exercise models of general coordinative manipulation(GCM) on the balance restoration of spine & extremities joints with distortions and mal-alignment areas. The subjects were the members who visited GCM Musculoskeletal Prevent Exercise Center from March 1 2012 to December 31 2013 because of spine & extremities joints distortion and mal-alignments, poor posture, and body type correction. All subjects were diagnosed with the four types of the GBT diagnosis. And according to the standards of the mobility vs stability types of the upper & lower body, they were classified into Group 1(40 persons) and Group 2(24 persons). For every other day for three times a week, GCM intervention models were applied to all subjects for four weeks, adding up to 12 times in total. Then the balance restoration effects were re-evaluated with the same methods. The results are as follows. 1) Balance restoration effects of VASdp(Visual analysis scale pain & discomfort) and ER(Equilibrium reaction: ER) came out higher in GCM body type(GBT) II III IV of Group 1. 2) In case of balance restoration effects in Moire and postural evaluation areas, Group 1 was higher and cervical and scapular girdle were higher in Group 2. The balance restoration of the four GBT types was significant in all regions(p<.05), and the scapular girdle came out as high in the order of GBTII IV I. 3) In case of thoracic-lumbar scoliosis and head rotation facial asymmetric cervical scoliosis ribcage forward, the balance restoration effects of the upper body postural evaluation areas came out the highest in Group 1 and Group 2, respectively. The balance restoration effects of the four GBT types were significant in all regions(p<.05), and came out the highest in lumbar scoliosis GBTIII I, ribcage forward and thoracic scoliosis GBTII IV. 4) The balance restoration effects of the lower body postural evaluation areas came out higher in Group 1 and Group 2 for pelvis girdle deviation patella high umbilicus tilt and hallux valgus foot longitudinal arch: FLA patella direction, respectively. The balance restoration effects of the four GBT types were significant in all regions(p<.05), and came out the highest in pelvis girdle deviation GBTIII I and patella high-direction GBTIV II I. 5) The balance restoration effects between the same GBT came out significant (p<.05) in all evaluation areas and items. The conclusions of this study was the manual intervention and self-corrective exercise models of the GCM about the mal-alignment of the spine & extremities joints across the whole body indicated high balance restoration effects(p<.05) in spine & extremities joints in all evaluation areas.