• Title/Summary/Keyword: Image Effect

Search Result 4,682, Processing Time 0.038 seconds

Experimental Study on the Effects of Ovariectomy and Estrogen on the Bone Pattern of Mandible in Rats (난소적출과 에스트로젠 투여가 백서의 하악골 구조에 미치는 영향)

  • Lee, Hyung-Soon;Hong, Sung-Gyu;Kim, Jong-Ghee
    • The korean journal of orthodontics
    • /
    • v.29 no.1 s.72
    • /
    • pp.83-94
    • /
    • 1999
  • The purpose of this study was to evaluate the changes of cancellous and cortical bone and the effect of estrogen in ovariectomized rats. Fifty female rats, 250gm in body weight, were divided into three groups : ovariectomized group(OVE), ovariectomized and estrogen-injected group(OVE-EST), and sham operated and estrogen-injected group(EST). Bilateral ovariectomy was performed at the onset of the experiment. In OVE-EST group and EST group, estrogen was injected $50{\mu}g/kg$ B.W. every other days from 3 weeks after surgery to sacrifice. Each five rats were sacrificed after 5, 6, 7 weeks. One side of mandibular body was radiographed with a soft x-ray apparatus(Hitex Co., Ltd., Japan). Thereafter the obtained microradiographs were used for the morphometric analysis using a Image analyzer. The morphometric analysis was perforrmed for parameters such as total bone area, cortex bone area and medullary bone area. The other side of the mandibular bone was decalcified and embedded in paraffin as using a general method. The specimens were sectioned and stained with Mallory's anilline blue and observed light microscopically. The results were as follows. 1 In all groups, the proportion of cortex to total bone area was not significantly different. 2. In ovariectomized(OVE) group, the proportion of marrow cavity to medullary bone area increased significantly from 5 to 7 weeks(p<0.05). In ovariectomized and estrogen-injected(OVE-EST) group, it decreased significantly at 7 weeks, and in estrogen-injected(EST) group, it decreased significantly from 6 weeks(p<0.05). 3. Microradiogram and histopathologic findings revealed that marrow cavity was enlarged and osteoclasts were observed around irregular bone surface in OVE group. In OVE-EST group, the size of marrow cavity at 7 weeks was similar to that of control group. In EST group, as dense trabecular bone increased from 5 to 7 weeks, marrow cavity decreased.

  • PDF

Dose Comparison of Treatment Plans Using Different Ir-192 Sources and Treatment Planning Systems for Intracavitary HDR Brachytherapy (고선량률 강내 근접치료에 사용되는 Ir-192 선원과 치료계획 시스템간의 계산선량 비교)

  • Park, Dong-Wook;Kim, Young-Seok;Park, Sung-Ho;Choi, Eun-Kyung;Kim, Jong-Hoon;Lee, Sang-Wook;Song, Si-Yeol;Ahn, Seung-Do;Noh, Young-Joo
    • Progress in Medical Physics
    • /
    • v.20 no.1
    • /
    • pp.1-6
    • /
    • 2009
  • For HDR intracavitary brachytherapy with ovoids and a tandem, we compared the dose discrepancy of treatment plans using two different Ir-192 sources (microSelectron, Varian) and generated on two different treatment planning systems (PLATO, BrachyVision). The treatment plans of ten patient treated from Oct. 2007 to Jan. 2008 were selected for these comparisons. For the comparison of dose calculation using different sources, the average discrepancies were $-0.91{\pm}0.09%$, $-0.27{\pm}0.07%$, $0.22{\pm}0.39%$, and $0.88{\pm}0.37%$ in total treatment time and at B-point and ICRU bladder and rectum reference point, respectively. Comparing the two systems, the average dose discrepancies between treatment planning programs were $-0.22{\pm}0.42%$, $-0.25{\pm}0.29%$, $-0.23{\pm}0.63%$, and $-0.17{\pm}0.76%$, and the average dose discrepancies between positioning methods (PLATO with film and BrachyVision with digitial image) were $-0.61{\pm}0.59%$, $-0.77{\pm}0.45%$, $-0.72{\pm}1.70%$, and $0.35{\pm}2.82%$ at A-point, B-point, and ICRU bladder and rectum reference points, respectively. The rectal dose discrepancies between two systems were reached 5.87%. The difference in the dwell position expected by each TPS are mainly affected by the differences in the positioning method in TPSs and have an effect on dose calculations of rectal and bladder located in AP direction.

  • PDF

The Effect of Glide Path on Canal Centering Ability in Reciprocating File System (Reciprocating 파일 시스템에서 Glide Path가 근관만곡도 유지에 미치는 영향)

  • Zang, Ki-Choul;Kim, Jin-Woo;Cho, Kyung-Mo;Park, Se-Hee
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • v.28 no.3
    • /
    • pp.245-252
    • /
    • 2012
  • The purpose of this study was to evaluate the influence of glide path on canal centering ratio after instrumentation with different single file systems; WaveOne and Reciproc. Reciproc R25 (VDW), WaveOne Primary (Dentsply Maillefer) and PathFile #13, 16, 19 (Dentsply Maillefer) were used in this study. In no glide path groups, Reciproc files and WaveOne files used for canal preparation without glide path. In glide path groups, the PathFile were used before canal preparation. Methylene blue dye was introduced into the canal to obtain a clear pre-instrumentation image. Pre-instrumentation images and post-instrumentation images were scanned using Epson Perfection V700 Photo scanner (Epson, Nagano, Japan). Transparencies of post-instrumentation images were changed and superimposed on pre-instrumentation images using Adobe Photoshop CS 3 (Adobe Systems Incorporated, San Jose, CA, USA). The centering ratio was calculated for each instrumented canal using the following formula: CR=|X1-X2|/Y. It was statistically analyzed using two-way ANOVA at 95% confidential level. The centering ratio in glide path groups were significant less than it in no glide path groups at 3, 4, 5 and 6 mm level. Except 1 and 6 mm level, WaveOne groups had significant less centering ration than Reciproc groups. At 6 mm level, there was no significant difference between WaveOne and Reciproc. In the limitation of this study, creation of a previous glide path before reciprocating motion instrumentation in curved canal appears to be appropriate and WaveOne system can be used for preparation of curved canal without severe aberrations.

Study on the Morphology of the PC/ABS Blend by High Shear Rate Processing (PC/ABS 블렌드의 고속전단성형에 따른 모폴로지 변화에 관한 연구)

  • Lee, Dong Uk;Yong, Da Kyoung;Lee, Han Ki;Choi, Seok Jin;Yoo, Jae Jung;Lee, Hyung Il;Kim, Seon-Hong;Lee, Kee Yoon;Lee, Seung Goo
    • Korean Chemical Engineering Research
    • /
    • v.52 no.3
    • /
    • pp.382-387
    • /
    • 2014
  • The PC/ABS blends were manufactured with high shear rate processing. Changes of the blend morphology were analyzed according to the screw speed and processing time. To find optimal conditions of the high shear rate processing of the PC/ABS blend, blend morphology and size of the dispersed phase, ABS, were observed with a SEM. Also, tensile properties of the PC/ABS blends were measured to investigate the effect of the high shear rate process with the screw speed of 500 rpm to 3000 rpm for processing times of 10s to 40s. Especially, to observe the dispersed phase of the PC/ABS blend clearly, fracture surfaces of the PC/ABS blend were etched with chromic acid solution. As screw speed and processing time increase, dispersed phase size of the PC/ABS blend decreases and mechanical properties of the blend decrease as well. Especially, at screw speed over than 1000 rpm of high shear rate processing, mechanical properties of the PC/ABS blends decrease drastically due to the degradation of the blend during the high shear rate processing. Consequently, the optimal condition of screw speed of the high shear processing of the PC/ABS blend is set at 1000rpm, in this study. Under optimal condition, the PC/ABS blend has relatively high mechanical properties with the relatively stable micro-structure having nanometer scale dispersed phase.

Signal Change of Iodinated Contrast Agents in MR Imaging (요오드화 조영제가 MR영상에 미치는 신호 변화)

  • Jeong, HK;Kim, Seongho;Kang, Chunghwan;Lee, Suho;Yi, Yun;Kim, Mingi;Kim, Hochul
    • Journal of the Institute of Electronics and Information Engineers
    • /
    • v.53 no.12
    • /
    • pp.131-138
    • /
    • 2016
  • In this study, we tried to analyze the influence of ICM(Iodinated Contrast Media) in MR imaging compare to GBCA(Gadolinium Based Contrast Agent), and as this result we discussed whether resonable or not the protocol which is MRI scan after enhanced CT scan without proper time interval in clinical field. For this research, we assembled two phantoms. which one was iodine and another one was gadolinium. We did test two phantoms in conventional MRI scan which is T1, T2, T2 FLAIR and 3D angio. After that, quantitative analysis was progressed. The results of study were as follow : SSI(Saline's Signal Intensity) was shown as each sequences 175, 1231, 333, 37 [a.u] at iodine. and 1297, 123, 757, 232 [a.u] was recorded at gadolinium. BDEPS(the Biggest Difference of EPS) was shown as each sequences 1297, 123, 757, 232 [a.u] at iodine and 793, 6, 1495, 365 [a.u] was recorded at gadolinium. At this time, EPS(Enhancement Percentage to Saline) was shown 641.1, -90.0, 127.3, 527% at iodine and 685.1, 99.4, 365.7, 1077.4% was recorded at gadolinium. BP(BDEPS's point) was shown 900, 900, 477, 900 mmol at iodine and 4, 0.2, 0.2, 40 mmol was recorded at gadolinium. CPSS(Change Point of SI to SSI) was shown 63, 423, 63, 29 mmol at iodine and each [50, 30], [4, 0.2], [4, 1], 0.2 mmol was recorded at gadolinium. According to this research, we could not only discover the fact that was iodine could effect on MR signal, but also the pattern is different as various sequences compare to gadolinium. Therefore, we expect useful diagnostic MR image in clinical field with this quantitative data for deciding protocol regarding MRI and CT scan order.

Development of a Passive Infrared Detector Algorithm for the Stop-line Detector of a Signalized Intersection (신호교차로의 정지선 검지기를 위한 수동형 적외선 검지기 알고리즘 개발(점유시간을 중심으로))

  • Jeong Sok-Min;Lee Seung-Hwan;Kim Nam-Sun
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.2 no.1 s.2
    • /
    • pp.25-40
    • /
    • 2003
  • The purpose of this thesis is development of detection algorithm for stop-line detector. Detail detection area is set in basing detection area($1.8{\times}4.0m$) and traffic information(volume, occupancy, nonoccupancy) is collected by passive infrared detector at designing detection area. The basis detection area($1.8{\times}4.0m$) is named existing PIR and detection area applied on development algorithm is named proposal PIR. The proposal PIR is collected data such volume, occupancy, nonoccupancy, speed and lane change, but this thesis is limited to evaluate for volume, occupancy and nonoccupancy The procedure and each step of being developed algorithm is described in the next (1) The detection area of proposal PIR is made up of 2 of $1.8{\times}0.6m$ size(the detection area is named 1 and 3) and 1 of $1.8{\times}1.78m$ size(the detection area is named 2) (2) The image detection area is set on monitor to analyze outdoor photographing data then video frame analysis has been done by analyzer. (3) The occupancy, nonoccupancy and speed data of vehicle have been collected with the detection area 1 and 3 and lane change has been collected with combination of detection area 1, 2 and 3 The MAD and MAPE have been utilized to being compared with volume, occupancy and nonoccupancy for the field application and evaluation of a algorithm As the result, the proposal PIR data have been identified superior to the existing PIR data and the effect has been improved its information(volume, occupancy and nonoccupancy)

  • PDF

A Study on Soviet Constructive Fashion in 1920s (1920년대 소비에트 구성주의 패션에 관한 연구)

  • 조윤경;금기숙
    • Journal of the Korean Society of Costume
    • /
    • v.36
    • /
    • pp.183-203
    • /
    • 1998
  • The wave of Avant-garde swept away all in the unique social background so called 'October Revolution' and the early 1900 Russian society which was able to absorb and accept anything. The Russian avant-garde has been affected by the Cubism and the Futurism those had peculiarly appeared in the early twentieth century, spreaded out to three spheres: the Suprematism, the Rayonism and the Constructivism. The Russian Constructivism has appeared in this background, concretely and ideally ex-pressed the ideology of the revolution into the artistic form and made an huge influence to the whole Russian society. The Constructivist like Tatlin, naum Gabo, Pevaner, Rodchenko, Stepanova, Popova and Exter gave great effect on the Soviet Constructive fashion design in 1920's after the Revolution. The Soviet costume in 1920s hold in common the characteristicss of the Constructive graphic as it is, geometrical and abstractive form, energetic and motility. In fashion design, these graphic qualities have been showed as the application of geometrical form and architectural image, physical distortion and transformation. And in textile design, the simple, dynamical presentation has been appeared. We can classify the Soviet costume at this time into three occasions. The first term is from late 1910 th mid 1920, and it is altered from folk costume design to modern one. With Lamanova as the first on the list, using the folk mitif, the Constructive expression of simple form has been gradually revealed in design. Designers like Makarova, Pribylskaia and Mukhina produced the plane, simple chemise style with the decoration of the Russian traditional motif. From early to late 1920 is the second term, and it is at the pick of the most active processing of the Constructive design. Not only at the costume in daily life but also at the theatrical costume and textile, the con-structive design has been represented all avail-able fields. Many Constructivists including Stepanova, Popova, Exter and Rodchenko took part in the textile design and costume design so as to evlvo their aesthetic concept. The third term is from late 1920 to early 1930. The socialistic realism has dominated over the whole culture and art, the revolutionary dynamic motif has been presented also in textile design. The formative features of Soviet Constructive fashion design are; silhouette, from, motif, color and fabric. The first, the silhouette : a straight rectangular silhouetted has been expressed through the whole period and a volumed one with distorted human body shape has introduced in the theatrical costume design. The second, the form: many lengthened rectangular forms have been made at beginnings, but to the middle period, geometrical, architectural forms have been more showed and there are energy and movement in design. At the last period, only a partial feature-division has been seen. The third, the motif; no pattern or ethnic motif has been partly used at beginnings, a figure like circle, tri-angle has gradually appeared in textile design. At latter period, a real-existent motif like an airplane has been represented with graphing and simplicity. The fourth, the color ; because of insufficient dyeing, neutral color like black or grey color has been mainly covered, but after middle term, a primary color or pastel tone has been seen, contrast of the fabric; without much development of textile industry after the Revolution, thick and durable fabrics have been the main stream, but as time had going to the last period, fabrics such as linen, cotton, velvet and silk have been varously choesn. At the theatrical costume, new materials like plastics and metals that were able to accentuate the form. The pursuit of popularity, simplicity and functionalism that the basic concept of Constructive fashion is one of the "beauty" which has been searching in modern fashion. And now we can appreciate how innovative and epochal this Soviet Constructive fashion movement was.ement was.

  • PDF

The Effectiveness Evaluation of Reconstruction Method Using DFOV Position Changes for Reduction of Artifact Around Hotspot in PET/CT Images (PET/CT 검사에서 열소 주변 인공물 감소를 위한 DFOV 위치 변화 재구성 방법의 유용성 평가)

  • Han, Dong Chan;Hong, Gun Chul;Choi, Choon ki;Lee, Hyeok;Choi, Seong Wook
    • The Korean Journal of Nuclear Medicine Technology
    • /
    • v.17 no.2
    • /
    • pp.90-94
    • /
    • 2013
  • Purpose: In the PET/CT images, various artifacts cause degradation of the quantitative assessment. Most hotspot generated by radiopharmaceutical injection errors cause an artifact and degrade the quality of the images as well as the accuracy of the quantitative evaluation. The purpose of this study is to assess effectiveness of the elimination of the hotspot at the injection sites using shifting the center of DFOV (Display Field of View, DFOV) method and evaluate the quantitative evaluation of result. Materials and Methods: GE Discovery STE 16 (GE Healthcare, Milwaukee, USA) and 1994 NEMA phantom were used for imaging acquisition. Phantom was filled with 0.005 MBq/mL of $^{18}F-FDG$. A hotspot was artificially placed on the outside of the phantom. The ratio of hotspot area activity to background area activity was regulated as 200:1. After image acquisition with routine protocol, all of the images were reconstructed using the shifting the center of DFOV method that wasn't overlapped with hotspot. Those images obtained before and after applying the shifting reconstruction method were compared. ROIs (Region Of Interests) were set in the hotspot areas, meanSUVs and standard deviations were calculated. Percentage differences were calculated with those meanSUVs and standard deviations. The evaluation on the effects of the shifting reconstruction method was done by comparison of the meanSUVs and the standard deviations, which were calculated for background areas unaffected by hotspot. Results: In the areas of unaffected by hotspot, meanSUVs before and after applying the shifting of center of DFOV method were $0.67{\pm}0.06g/mL$ and $0.65{\pm}0.06g/mL$, respectively. In the artifact areas affected by hotspot, meanSUVs before and after applying the shifting of center of DFOV method were $0.32{\pm}0.08g/mL$ and $0.56{\pm}0.12g/mL$, respectively. The percentage differences of the area adjacent to the hotspot and the area distant from the hotspot were 65.3% and 97.4%, respectively. Conclusion: In the PET/CT images, meanSUV was improved by 32.1% when the effect of artifact was removed with application of the shifting the center of DFOV methode. In other areas unaffected by artifacts, meanSUVs were not significantly different after applying DFOV center shift method. As shown in the result, adverse effects of hotspot made by swelling in the injection site can be reduced by applying DFOV center shift method. Therefore, DFOV center shift method can be applied for the more precise quantitative evaluation, and contribute to the increase of the diagnostic value of the images.

  • PDF

Verification of Radiation Therapy Planning Dose Based on Electron Density Correction of CT Number: XiO Experiments (컴퓨터영상의 전자밀도보정에 근거한 치료선량확인: XiO 실험)

  • Choi Tae-Jin;Kim Jin-Hee;Kim Ok-Bae
    • Progress in Medical Physics
    • /
    • v.17 no.2
    • /
    • pp.105-113
    • /
    • 2006
  • This study peformed to confirm the corrected dose In different electron density materials using the superposition/FFT convolution method in radiotherapy Planning system. The experiments of the $K_2HPO_4$ diluted solution for bone substitute, Cork for lung and n-Glucose for soft tissue are very close to effective atomic number of tissue materials. The image data acquisited from the 110 KVp and 130 KVp CT scanner (Siemes, Singo emotions). The electron density was derived from the CT number (H) and adapted to planning system (Xio, CMS) for heterogeneity correction. The heterogeneity tissue phantom used for measurement dose comparison to that of delivered computer planning system. In the results, this investigations showed the CT number is highly affected in photoelectric effect in high Z materials. The electron density in a given energy spectrum showed the relation of first order as a function of H in soft tissue and bone materials, respectively. In our experiments, the ratio of electron density as a function of H was obtained the 0.001026H+1.00 in soft tissue and 0.000304H+1.07 for bone at 130 KVp spectrum and showed 0.000274H+1.10 for bone tissue in low 110 KVp. This experiments of electron density calibrations from CT number used to decide depth and length of photon transportation. The Computed superposition and FFT convolution dose showed very close to measurements within 1.0% discrepancy in homogeneous phantom for 6 and 15 MV X rays, but it showed -5.0% large discrepancy in FFT convolution for bone tissue correction of 6 MV X rays. In this experiments, the evaluated doses showed acceptable discrepancy within -1.2% of average for lung and -2.9% for bone equivalent materials with superposition method in 6 MV X rays. However the FFT convolution method showed more a large discrepancy than superposition in the low electron density medium in 6 and 15 MV X rays. As the CT number depends on energy spectrum of X rays, it should be confirm gradient of function of CT number-electron density regularly.

  • PDF

Reducing of Craniofacial Radiation Dose Using Automatic Exposure Control Technique in the 64 Multi-Detector Computed Tomography (64 다중 검출기 전산화단층촬영에서 관전류 자동노출조절 기법을 이용한 두개부 방사선량 감소 정도 평가)

  • Seoung, Youl-Hun;Kim, Yong-Ok;Choe, Bo-Young
    • Progress in Medical Physics
    • /
    • v.21 no.2
    • /
    • pp.137-144
    • /
    • 2010
  • The purpose of this study was to evaluate the usefulness of reducing of craniofacial radiation dose using automatic exposure control (AEC) technique in the 64 multi-detector computed tomography (MDCT). We used SOMATOM Definition 64 multi-detector CT, and head of whole body phantom (KUPBU-50, Kyoto Kagaku CO. Ltd). The protocol were helical scan method with 120 kVp, 1 sec of rotation time, 5 mm of slice thickness and increment, 250 mm of FOV, $512{\times}512$ of matrix size, $64{\times}0.625\;mm$ of collimation, and 1 of pitch. The evaluation of dose reducing effect was compared the fixed tube current of 350 with AEC technique. The image quality was measured the noise using standard deviation of CT number. The range of craniofacial bone was to mentum end from calvaria apex, which devided three regions: calvaria~superciliary ridge (1 segment), superciliary ridge~acanthion (2 segment), and acanthion~mentum (3 segment). In the fixed tube current technique, CTDIvol was 57.7 mGy, DLP was $640.2\;mGy{\cdot}cm$ in the all regions. The AEC technique was showed that 1 segment were 30.7 mGy of CTDIvol, 340.7 $mGy{\cdot}cm$ of DLP, 2 segment were 46.5 mGy of CTDIvol, $515.0\;mGy{\cdot}cm$ of DLP, and 3 segment were 30.3 mGy of CTDIvol, $337.0\;mGy{\cdot}cm$ of DLP. The standard deviation of CT number was 2.622 with the fixed tube current technique and 3.023 with the AEC technique in the 1 segment, was 3.118 with the fixed tube current technique and 3.379 with the AEC technique in the 2 segment, was 2.670 with the fixed tube current technique and 3.186 with the AEC technique in the 3 segment. The craniofacial radiation dose using AEC Technique in the 64 MDCT was evaluated the usefulness of reducing for the eye, the parotid and thyroid with high radiation sensitivity particularly.