• Title/Summary/Keyword: MEAN SHIFT

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Evaluation of Target Position's Accuracy in 2D-3D Matching using Rando Phantom (인체팬톰을 이용한 2D-3D 정합시 타켓위치의 정확성 평가)

  • Jang, Eun-Sung;Kang, Soo-Man;Lee, Chul-Soo
    • The Journal of Korean Society for Radiation Therapy
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    • v.21 no.1
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    • pp.33-39
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    • 2009
  • Purpose: The aim of this study is to compare patient's body posture and its position at the time of simulation with one at the treatment room using On-board Imaging (OBI) and CT (CBCT). The detected offsets are compared with position errors of Rando Phantom that are practically applied. After that, Rando Phantom's position is selected by moving couch based on detected deviations. In addition, the errors between real measured values of Rando Phantom position and theoretical ones is compared. And we will evaluate target position's accuracy of KV X-ray imaging's 2D and CBCT's 3D one. Materials and Methods: Using the Rando Phantom (Alderson Research Laboratories Inc. Stanford. CT, USA) which simulated human body's internal structure, we will set up Rando Phantom on the treatment couch after implementing simulation and RTP according to the same ways as the real radioactive treatment. We tested Rando Phantom that are assumed to have accurate position with different 3 methods. We measured setup errors on the axis of X, Y and Z, and got mean standard deviation errors by repeating tests 10 times on each tests. Results: The difference between mean detection error and standard deviation are as follows; lateral 0.4+/-0.3 mm, longitudinal 0.6+/-0.5 mm, vertical 0.4+/-0.2 mm which all within 0~10 mm. The couch shift variable after positioning that are comparable to residual errors are 0.3+/-0.1, 0.5+/-0.1, and 0.3+/-0.1 mm. The mean detection errors by longitudinal shift between 20~40 mm are 0.4+/-0.3 in lateral, 0.6+/-0.5 in longitudinal, 0.5+/-0.3 in vertical direction. The detection errors are all within range of 0.3~0.5 mm. Residual errors are within 0.2~0.5 mm. Each values are mean values based on 3 tests. Conclusion: Phantom is based on treatment couch shift and error within the average 5mm can be gained by the diminution detected by image registration based on OBI and CBCT. Therefore, the selection of target position which depends on OBI and CBCT could be considered as useful.

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Anatomical Distribution of Colorectal Carcinoma in Iran: A Retrospective 15-yr Study to Evaluate Rightward Shift

  • Omranipour, Ramesh;Doroudian, Rana;Mahmoodzadeh, Habibollah
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.1
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    • pp.279-282
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    • 2012
  • Background: Although more than two third of colorectal cancers are localized on the left side, recent studies suggest a right ward shift in anatomical distribution with increase in proximal colon cancers. The aim of the present study was to determine the anatomical distribution of colorectal cancer in a referral center over a 15 year period. Method: Records of patients who underwent colectomy in the Cancer Institute of Iran from 1994 to 2009 were retrieved. Data including anatomical localization, year of diagnosis, patient age and gender, tumor histology and differentiation, and disease stage were extracted. Tumors located from the cecum to the distal transverse colon were classified as right side and those occurring from the splenic flexure to the descending colon as left-sided. Cancer of rectum and recto-sigmoid junction were considered as rectal cancers. Results: A total of 442 patients including 220 (49/8%) men and 222 (50/2%) women with mean age 53 were included. Most patients were in stage II &III (47.1% and 33% respectively). There were 157 (35.5 %) colon cancers and 285 (64.5%) rectal cancers. 43.3% of the colon cancers were right sided and 56.7% were left sided. There was no statistically significant increase in right sided cancer during the period of the study. There were no significant differences in age at diagnosis, gender, grade and stage of tumor between the right and the left sided cancers. Conclusion: No proximal shift over time was identified in our study.

On the Origin of the Oosterhoff Dichotomy among Globular Clusters and Dwarf Galaxies

  • Jang, Sohee;Lee, Young-Wook;Joo, Seok-Joo;Na, Chongsam
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.2
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    • pp.67.2-67.2
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    • 2014
  • The presence of multiple populations is now well-established in most globular clusters in the Milky Way. In light of this progress, here we suggest a new model explaining the origin of the Sandage period-shift and the difference in mean period of type ab RR Lyrae variables between the two Oosterhoff groups. In our models, the instability strip in the metal-poor group II clusters, such as M15, is populated by second generation stars (G2) with enhanced helium and CNO abundances, while the RR Lyraes in the relatively metal-rich group I clusters like M3 are mostly produced by first generation stars (G1) without these enhancements. This population shift within the instability strip with metallicity can create the observed period-shift between the two groups, since both helium and CNO abundances play a role in increasing the period of RR Lyrae variables. The presence of more metal-rich clusters having Oosterhoff-intermediate characteristics, such as NGC 1851, as well as of most metal-rich clusters having RR Lyraes with longest periods (group III) can also be reproduced, as more helium-rich third and later generations of stars (G3) penetrate into the instability strip with further increase in metallicity. Therefore, although there are systems where the suggested population shift cannot be a viable explanation, for the most general cases, our models predict that the RR Lyraes are produced mostly by G1, G2, and G3, respectively, for the Oosterhoff groups I, II, and III.

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$^{13}C$ Nuclear Magnetic Resonance Study of Graphite Intercalated Superconductor $CaC_6$ Crystals in the Normal State ($CaC_6$ 결정에 대한 정상상태에서의 $^{13}C$ 핵자기공명 측정)

  • Kim, Sung-Hoon;Kang, Ki-Hyeok;Mean, B.J.;Ndiaye, B.;Lee, Moo-Hee;Kim, Jun-Sung
    • Progress in Superconductivity
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    • v.12 no.1
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    • pp.51-56
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    • 2010
  • $^{13}C$ NMR (nuclear magnetic resonance) measurements have been performed to investigate the local electronic structure of a superconducting graphite intercalation compound $CaC_6$ ($T_c$ = 11.4 K). A large number of single crystals were stacked and sealed in a quartz tube for naturally abundant $^{13}C$ NMR. The spectrum, Knight shift, linewidth, and spin-lattice relaxation time $T_1$ were measured in the normal state as a function of temperature down to 80 K at 8.0 T perpendicular to the c-axis. The $^{13}C$ NMR spectrum shows a single narrow peak with a very small Knight shift. The Knight shift and the linewidth of the $^{13}C$ NMR are temperature-independent around, respectively, +0.012% and 1.2 kHz. The spin-lattice relaxation rate, $1/T_1$, is proportional to temperature confirming a Korringa behavior as for non-magnetic metals. The Korringa product is measured to be $T_1T\;=\;210\;s{\cdot}K$. From this value, the Korringa ratio is deduced to be $\xi$ = 0.73, close to unity, which suggests that the independent-electron description works well for $CaC_6$, without complications arising from correlation and many-body effects.

Comparison of Anterior Cruciate Ligament Reconstructions Using Hamstring Tendon Autograft and Tibialis Tendon Allograft (자가 슬괵건 및 동종 경골건을 이용한 전방 십자 인대 재건술의 결과 비교)

  • Song, Eun-Kyoo;Seon, Jong-Keun;Bae, Bong-Hyun;Park, Sang-Jin;Kim, Jong-Seon;Lee, Dam-Seon
    • Journal of the Korean Arthroscopy Society
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    • v.10 no.2
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    • pp.141-147
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    • 2006
  • Purpose: To compare the clinical and radiological results of anterior cruciate ligament(ACL) reconstruction using hamstring autograft and tibialis tendon allograft. Materials and Methods: Twenty four ACL reconstructions using hamstring autograft and 30 using tibialis anterior tendon altograft were followed up at least 1 year. We performed femoral tunnel fixation with Ligament Anchor(LA) screw and tibial tunnel fixation with biodegradable interference screw. Evaluations included Lysholm knee(LK) score, Tegner activity scale, Lachman test, Pivot-Shift test, Quardriceps atrophy, incision site numbness, anterior knee pain and instrumented anterior laxity with $Telos^{(R)}$ device. Results: Preoperativ mean LK score was $60.3(18{\sim}82)$ in autograft group and 61.2(25-80) in allograft group. Mean LK score improved to $91.6(68{\sim}100)\;and\;92.6(77{\sim}100)$ respectively. Activity level, using Tegner activity scale, slightly decreased compared with that of Preinjury state in both groups. Lachman test, pivot-shift test, Quadriceps atrophy, anterior knee pain, incision site numbness, and anterior drawer test using $Telos^{(R)}$ device showed no significant difference between two groups (p>0.05). Conclusion: In performing the ACL reconstruction, there was no statistically significant difference between hamstring autograft group and tibilis anterior allograft group in clinical or in radiological results.

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A Study on the Perception Level of Nursing Activities of Nurses in General Hospitals (일부 대학병원 간호사의 업무인지정도에 관한 조사연구)

  • Kim, Chun-Gil
    • The Korean Nurse
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    • v.30 no.1
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    • pp.51-62
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    • 1991
  • The Study was carried out for the purpose of investigating the degree of perception in nursing activities. This study reports perceptions of nurses on the choices they make among competing activities, contrasts this perception with their opinion of what tasks they would like to spend time on. A sample of 231 clinical nurses was selected to participate in this study at two genernal hospitals in Seoul. The data was collected from July 10th to 25th, 1990. Subjects were instructed to rate one of five points likert type scale on the 43 items of nursing activities. Analysis of data was done by means of the SPSS-X Program using frequency, t-test and ANOVA. The results of this study were as follows; 1. The characteristics of the subjects were as follows: The age group of 25-29 yeares was 45.9%. For religion, Christians had the highest score, 68.4 % and singles in subjects were 81.4%. For academic background, 64.5% were graduated from nursing junior colleges. In the subjects, staff nurses were 86.6%. 22.5% of them had worked for less than 1 year and 20.8% had 37 months to 5 years experience at the time of the survey. 62.8% were satisfied with the job. 2. The perception level of nursing activities: 1) The mean score for perception of professional nursing functions was 4.157 point, with a maximum score set. at 5 points. The mean score for perception of priorities was 3.781. Perception of spending time was 3.932. 2) In perception of professional nursing functions, more important items were Aseptic technique (4.866), Shift and exchange of information concerning patients(4.654), Observing patients (4.799). Less important items were Transporting patients(3.411), Changing linens(3.442), Giving a bed shampoo (3.506). In priorities, more important ones. were Aseptic technique(4, 706), Shift and exchange of information concerning patients (4.524.), Observing patients(4.390), Taking vital signs (4.355). And less important ones were Changing linens (3.100), Giving bed baths(3.113), Giving back rubs(3.121). In spending time, more important ones were Aseptic technique(1.706), Observing patients (4.532), Shift and exchange of information concerning patients(4.532). And less important ones were Changing lines(3.368), Transporting patients(3.394), Giving bed baths(3.450). 3) In the role perception level, the mean distribution of perception was 3.511- 4.335; the role was perceived to be in order of frequency as a facilitator, coordinator, change agent and advocator role. The most important scale of factors by nursing activities was indirect nursing activities.

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Health of Apartment Guards and Associated Factors (아파트 경비원의 건강상태와 관련요인)

  • Kim, Sang-Kyu;SaKong, Joon;Chung, Jong-Hak;Kim, Chi-Ho;Bae, Sang-Keun;Jang, Yun-Jin
    • Journal of Yeungnam Medical Science
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    • v.16 no.2
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    • pp.357-363
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    • 1999
  • Objectives: The purpose of this investigation was to study the health status of apartment guards and associated factors. Materials and Methods: This investigation was conducted for 1 month starting from August, 1997. Study population in this cross-sectional survey consisted of 182 guards of apartments located throughout the district of Taegu. Each subject completed a questionnaire about his general characteristics, health behaviors, job descriptions, subjective GIT symptoms and somatization and depression using Symptom Checklist-90-Reversion (SCL-90-R) by self administrated questionnaire and personal interview. Results: Study subjects had one or more GIT symptoms(53.3%), somatization symptoms(83.5%) and depression symptoms(79.7%). The mean scores of GIT, somatization and depression symptoms were not different among the age groups and based on marital status, respectively, but, significantly different by education level(p<0.05). The mean scores of GIT, somatization and depression symptoms were not different among the age group and based on marital status, respectively, but, significantly different by regular diet and by the subject's health status(p<0.05). The mean scores of GIT, somatization and depression symptoms were not different by duration of shift work, by job tenure and by the number of managed houses but, those of somatization and depression symptoms were significantly different by level of job satisfaction(p<0.05). Conclusion: The health statuses of guards at apartments were different from other shift workers because of healthy worker effects and characteristics of their jobs.

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Differences in Temporary Threshold Shift and Recovery Patterns Depending on Sound Type and Pressure (소리의 종류와 크기에 따른 일과성 청력 역치 상승과 회복의 차이)

  • Lee, Chae Kwan
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.30 no.4
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    • pp.387-393
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    • 2020
  • Objective: This study aimed to investigate the differences in temporary threshold shift (TTS) and recovery patterns according to different types of sound and volume. Methods: TTS and recovery patterns were assessed for eight students after 30-minute exposure to both 70.0 dB and 90.0 dB of factory noise (noise) as well as music. TTS was measured before exposure and two minutes post exposure, and recovery patterns were evaluated every 10 minutes for one hour. The subjects performed activities of daily life and sleeping times as usual but taking drugs or drinking alcohol were prohibited. The experiment was repeated three times with an interval of at least 16 hours. ANOVA and T-test were carried out using SPSS 19.0 for Windows. Results: The hearing threshold of all subjects before exposure was less than 30 dB at all frequencies. Mean TTSs of 70 dB noise and 90 dB noise exposure were 0.14 and 4.48 dB (p<0.001). Meanwhile, the difference in music was insignificant (-0.63 dB and 0.55 dB, p=0.063). A significance in the difference was also found between the mean TTS of music and noise exposure, more obviously at 90.0 dB (p<0.001) than at 70 dB (p=0.232). The TTS differences were found frequency-wise in terms of sound type. Mean TTS by frequency was higher at 4,000 and 6,000 Hz than at other frequencies, and higher in noise than music at the same sound pressure. The TTS difference in each frequency between both sound types was significant at 90 dB (p<0.001). Subjects mostly recovered from TTS in one hour after exposure, but not with 90 dB-noise exposure. Conclusion: TTS and recovery patterns were different depending on the sound type. When exposed to factory noise, TTS was greater and recovery time was longer compared to music at the same sound pressure. These results suggested that the difference in cognitive processes and psychological factors according to the type of sound causes a change in TTS and recovery.

Detection and Classification of Leaf Diseases for Phenomics System (피노믹스 시스템을 위한 식물 잎의 질병 검출 및 분류)

  • Gwan Ik, Park;Kyu Dong, Sim;Min Su, Kyeon;Sang Hwa, Lee;Jeong Hyun, Baek;Jong-Il, Park
    • Journal of Broadcast Engineering
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    • v.27 no.6
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    • pp.923-935
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    • 2022
  • This paper deals with detection and classification of leaf diseases for phenomics systems. As the smart farm systems of plants are increased, It is important to determine quickly the abnormal growth of plants without supervisors. This paper considers the color distribution and shape information of leaf diseases, and designs two deep leaning networks in training the leaf diseases. In the first step, color distribution of input image is analyzed for possible diseases. In the second step, the image is first partitioned into small segments using mean shift clustering, and the color information of each segment is inspected by the proposed Color Network. When a segment is determined as disease, the shape parameters of the segment are extracted and inspected by proposed Shape Network to classify the leaf disease types in the third step. According to the experiments with two types of diseases (frogeye/rust and tipburn) for apple leaves and iceberg, the leaf diseases are detected with 92.3% recall for a segment and with 99.3% recall for an input image where there are usually more than two disease segments. The proposed method is useful for detecting leaf diseases quickly in the smart farm environment, and is extendible to various types of new plants and leaf diseases without additional learning.

A Study on UBM Method Detecting Mean Shift in Autocorrelated Process Control

  • Jun, Sang-Pyo
    • Journal of the Korea Society of Computer and Information
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    • v.25 no.12
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    • pp.187-194
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    • 2020
  • In today's process-oriented industries, such as semiconductor and petrochemical processes, autocorrelation exists between observed data. As a management method for the process where autocorrelation exists, a method of using the observations is to construct a batch so that the batch mean approaches to independence, or to apply the EWMA (Exponentially Weighted Moving Average) statistic of the observed value to the EWMA control chart. In this paper, we propose a method to determine the batch size of UBM (Unweighted Batch Mean), which is commonly used as a management method for observations, and a method to determine the optimal batch size based on ARL (Average Run Length) We propose a method to estimate the standard deviation of the process. We propose an improved control chart for processes in which autocorrelation exists.