• Title/Summary/Keyword: Different Version

Search Result 949, Processing Time 0.025 seconds

Object Tracking Based on Exactly Reweighted Online Total-Error-Rate Minimization (정확히 재가중되는 온라인 전체 에러율 최소화 기반의 객체 추적)

  • JANG, Se-In;PARK, Choong-Shik
    • Journal of Intelligence and Information Systems
    • /
    • v.25 no.4
    • /
    • pp.53-65
    • /
    • 2019
  • Object tracking is one of important steps to achieve video-based surveillance systems. Object tracking is considered as an essential task similar to object detection and recognition. In order to perform object tracking, various machine learning methods (e.g., least-squares, perceptron and support vector machine) can be applied for different designs of tracking systems. In general, generative methods (e.g., principal component analysis) were utilized due to its simplicity and effectiveness. However, the generative methods were only focused on modeling the target object. Due to this limitation, discriminative methods (e.g., binary classification) were adopted to distinguish the target object and the background. Among the machine learning methods for binary classification, total error rate minimization can be used as one of successful machine learning methods for binary classification. The total error rate minimization can achieve a global minimum due to a quadratic approximation to a step function while other methods (e.g., support vector machine) seek local minima using nonlinear functions (e.g., hinge loss function). Due to this quadratic approximation, the total error rate minimization could obtain appropriate properties in solving optimization problems for binary classification. However, this total error rate minimization was based on a batch mode setting. The batch mode setting can be limited to several applications under offline learning. Due to limited computing resources, offline learning could not handle large scale data sets. Compared to offline learning, online learning can update its solution without storing all training samples in learning process. Due to increment of large scale data sets, online learning becomes one of essential properties for various applications. Since object tracking needs to handle data samples in real time, online learning based total error rate minimization methods are necessary to efficiently address object tracking problems. Due to the need of the online learning, an online learning based total error rate minimization method was developed. However, an approximately reweighted technique was developed. Although the approximation technique is utilized, this online version of the total error rate minimization could achieve good performances in biometric applications. However, this method is assumed that the total error rate minimization can be asymptotically achieved when only the number of training samples is infinite. Although there is the assumption to achieve the total error rate minimization, the approximation issue can continuously accumulate learning errors according to increment of training samples. Due to this reason, the approximated online learning solution can then lead a wrong solution. The wrong solution can make significant errors when it is applied to surveillance systems. In this paper, we propose an exactly reweighted technique to recursively update the solution of the total error rate minimization in online learning manner. Compared to the approximately reweighted online total error rate minimization, an exactly reweighted online total error rate minimization is achieved. The proposed exact online learning method based on the total error rate minimization is then applied to object tracking problems. In our object tracking system, particle filtering is adopted. In particle filtering, our observation model is consisted of both generative and discriminative methods to leverage the advantages between generative and discriminative properties. In our experiments, our proposed object tracking system achieves promising performances on 8 public video sequences over competing object tracking systems. The paired t-test is also reported to evaluate its quality of the results. Our proposed online learning method can be extended under the deep learning architecture which can cover the shallow and deep networks. Moreover, online learning methods, that need the exact reweighting process, can use our proposed reweighting technique. In addition to object tracking, the proposed online learning method can be easily applied to object detection and recognition. Therefore, our proposed methods can contribute to online learning community and object tracking, detection and recognition communities.

Clinical Usefulness of Contrast Echocardiography: The Dose Effect for Left Ventricle Visualization in Dogs (심초음파의 조영제의 임상적 유용성: 개에서 좌심영상화에 대한 조영제 용량의 영향)

  • Shin, Chang-ho;Hwang, Tae-sung;Yoon, Young-min;Jung, Dong-in;Yeon, Seong-chan;Lee, Hee-chun
    • Journal of Veterinary Clinics
    • /
    • v.32 no.6
    • /
    • pp.486-490
    • /
    • 2015
  • Two-demensional echocardiography is routinely used for evaluation of cardiac function. Visualization of the endocardial border is essential for the assessment of global and regional left ventricular with cardiac disease. SonoVue$^{TM}$ is a microbubble contrast agent that consists of sulfur hexafluoride-filled microbubbles in a phospholipid shell. There were many studies about contrast echocardiographic examination using SonoVue$^{TM}$ contrast agent, and various doses of SonoVue$^{TM}$ were used. To our knowledge, in published veterinary medicine, there was not reported for diagnostic efficient dose of SonoVue$^{TM}$ to evaluate contrast enhanced left ventricular endocardial border delineation (LVEBD). The purpose of this study is to compare the visualization time of LVEBD and find efficient dose of SonoVue$^{TM}$ for using various doses in dogs. Ten healthy Beagles were recruited to the study. Three different doses (0.03 ml/kg, 0.05 ml/kg and 0.1 ml/kg) of SonoVue$^{TM}$ were injected. Endocardial segments were assigned based on previously established methodology, where by the four-chamber views of the LV were divided into 6 segments. In this study, Contrast enhancement of the LVEBD after each injection was evaluated visually at the time point of overall contrast enhancement (Segmental scoring 5+) in the LV by three investigators in a blind manner. Statistical analysis was performed with SPSS version 14.0. All data were analyzed using one-way ANOVA, the multiple comparison Scheffe test. When data for the three offsite readers were combined, mean durations of useful contrast were $3.54({\pm}2.14)$, $6.15({\pm}2.61)$, and $24.39({\pm}11.10)$ seconds for the 0.03 ml/kg, 0.05 ml/kg, and 0.1 ml/kg SonoVue$^{TM}$ doses, respectively. After injection of contrast agent, there were no significant change in side effects such as urticaria, angioedema, hypersensitivity reactions, and digestive system disorders. This study suggests that efficient dose of SonoVue$^{TM}$ contrast agent for improvement of the left ventricle visualization is 0.1 ml/kg. The duration of useful enhancement of LVEBD and the reproducibility were also the highest at the 0.1 ml/kg dosage.

A Study on Actual Usage of Information Systems: Focusing on System Quality of Mobile Service (정보시스템의 실제 이용에 대한 연구: 모바일 서비스 시스템 품질을 중심으로)

  • Cho, Woo-Chul;Kim, Kimin;Yang, Sung-Byung
    • Asia pacific journal of information systems
    • /
    • v.24 no.4
    • /
    • pp.611-635
    • /
    • 2014
  • Information systems (IS) have become ubiquitous and changed every aspect of how people live their lives. While some IS have been successfully adopted and widely used, others have failed to be adopted and crowded out in spite of remarkable progress in technologies. Both the technology acceptance model (TAM) and the IS Success Model (ISSM), among many others, have contributed to explain the reasons of success as well as failure in IS adoption and usage. While the TAM suggests that intention to use and perceived usefulness lead to actual IS usage, the ISSM indicates that information quality, system quality, and service quality affect IS usage and user satisfaction. Upon literature review, however, we found a significant void in theoretical development and its applications that employ either of the two models, and we raise research questions. First of all, in spite of the causal relationship between intention to use and actual usage, in most previous studies, only intention to use was employed as a dependent variable without overt explaining its relationship with actual usage. Moreover, even in a few studies that employed actual IS usage as a dependent variable, the degree of actual usage was measured based on users' perceptual responses to survey questionnaires. However, the measurement of actual usage based on survey responses might not be 'actual' usage in a strict sense that responders' perception may be distorted due to their selective perceptions or stereotypes. By the same token, the degree of system quality that IS users perceive might not be 'real' quality as well. This study seeks to fill this void by measuring the variables of actual usage and system quality using 'fact' data such as system logs and specifications of users' information and communications technology (ICT) devices. More specifically, we propose an integrated research model that bring together the TAM and the ISSM. The integrated model is composed of both the variables that are to be measured using fact as well as survey data. By employing the integrated model, we expect to reveal the difference between real and perceived degree of system quality, and to investigate the relationship between the perception-based measure of intention to use and the fact-based measure of actual usage. Furthermore, we also aim to add empirical findings on the general research question: what factors influence actual IS usage and how? In order to address the research question and to examine the research model, we selected a mobile campus application (MCA). We collected both fact data and survey data. For fact data, we retrieved them from the system logs such information as menu usage counts, user's device performance, display size, and operating system revision version number. At the same time, we conducted a survey among university students who use an MCA, and collected 180 valid responses. A partial least square (PLS) method was employed to validate our research model. Among nine hypotheses developed, we found five were supported while four were not. In detail, the relationships between (1) perceived system quality and perceived usefulness, (2) perceived system quality and perceived intention to use, (3) perceived usefulness and perceived intention to use, (4) quality of device platform and actual IS usage, and (5) perceived intention to use and actual IS usage were found to be significant. In comparison, the relationships between (1) quality of device platform and perceived system quality, (2) quality of device platform and perceived usefulness, (3) quality of device platform and perceived intention to use, and (4) perceived system quality and actual IS usage were not significant. The results of the study reveal notable differences from those of previous studies. First, although perceived intention to use shows a positive effect on actual IS usage, its explanatory power is very weak ($R^2$=0.064). Second, fact-based system quality (quality of user's device platform) shows a direct impact on actual IS usage without the mediating role of intention to use. Lastly, the relationships between perceived system quality (perception-based system quality) and other constructs show completely different results from those between quality of device platform (fact-based system quality) and other constructs. In the post-hoc analysis, IS users' past behavior was additionally included in the research model to further investigate the cause of such a low explanatory power of actual IS usage. The results show that past IS usage has a strong positive effect on current IS usage while intention to use does not have, implying that IS usage has already become a habitual behavior. This study provides the following several implications. First, we verify that fact-based data (i.e., system logs of real usage records) are more likely to reflect IS users' actual usage than perception-based data. In addition, by identifying the direct impact of quality of device platform on actual IS usage (without any mediating roles of attitude or intention), this study triggers further research on other potential factors that may directly influence actual IS usage. Furthermore, the results of the study provide practical strategic implications that organizations equipped with high-quality systems may directly expect high level of system usage.

Is Moral Identity theory a post-kohlbergian? - The function of the reflective reasoning in the moral identity theory and it's implication (도덕적 정체성 이론은 탈 콜버그주의인가?)

  • Son, Kyung-Won
    • The Journal of Korean Philosophical History
    • /
    • no.32
    • /
    • pp.395-432
    • /
    • 2011
  • The purpose of this study is (i) to explore arguments of post-kohlbergian approach in moral psychology and; (ii) to analyze Blasi's and Lapsley's positions regarding the relationship between moral philosophy and psychology in terms of reflective reasoning and; (ⅲ) to suggest their's implication concerning the future development of moral identity theory. Moral identity theory has emerged as an alternative approach of the Kohlberg's moral development theory. Theorists of moral identity theory commonly criticize Kohlberg's theory as a philosophical psychology and insist the autonomy of moral psychology. However, one can find different positions within this trend, especially concerning he meaning and role of the reflection in moral functioning. Blasi emphasizes the importance of the reflective reasoning of moral agent, while Lapsley supports moral automacy contrary to Kohlberg's phenomenalism. Although Blasi had been negative about building moral psychology based on the moral philosophy, he has articulated the moral identity theory based on the concept of free will by Frankfurt. However, recently he criticizes intuitionist theory of Haidit and suggests the notion of the moral agent with the skill of reflective reasoning, or post-conventional thinking in Kohlberg's terms. Blasi's perspective of moral identity has two version. The one emphasizes the moral understanding which means strong evaluation, while the other refers to reasoning with weak evaluation. This leads to an inevitable inner contradiction within his theory of moral identity. Lapsley considers moral identity as a heuristic idea and suggests moral chronic as a new model of moral identity. This model is based on the social cognitive theory. His social cognitive model of moral personality provides the account for implicit, tacit, and automatic of moral functioning, while reflecting the core of moral identity. Lapsley suggests that moral function involves conscious and unconscious processes. The former occurs in normal situations of life, while the latter in rare and unusual situations. He does not highlight reasoning in moral functioning as Blasi do. In consequence, I will argue the notion of the moral agent with the skill of reflective reasoning, or post conventional thinking in Kohlberg's terms in the moral functioning like Gibbs and Turiel positions in the Journal of Moral Education' s 2008 special issue. Moral philosophy and psychology should be in complementary relations. It means we explore not only more interdisciplinary researches on the moral functioning, but also researches based on the moral philosophy.

A musical study on Kangwon Sangkangrye - Focusing on the perfoming style of Chogye Order - ('강원상강례(講院上講禮)'의 음악적 연구 - 조계종을 중심으로 -)

  • Cha, Hyoung-Suk
    • (The) Research of the performance art and culture
    • /
    • no.37
    • /
    • pp.391-435
    • /
    • 2018
  • This is the first study in Musicology that discusses the features of Kangwon Sangkangrye(the pre-lecture ritual in Buddhism). In this thesis, I reviewed and compared the similarity and uniqueness between Kangwon Sangkangrye in "Seokmunuibom" and the one being performed these days. The musical relation between the performance shown in the historical record and the one in contemporary ritual was illustrated here based on the findings derived from the anlaysis on its bell(小鐘) performance. The analysis made upon musical sources recorded on-site shows the characteristics of contemporary Kangwon Sangkangrye. Following is a brief summary of this study. The review and comparison between Kangwon Sangkangrae in "Seokmunuibom" and the one being performed these days showed that the second type, which was significantly different from the first type, was closer to that of the historical record. The performers at Unmunsa Temple and Chungamsa Temple seemed to be following the tradition bell(小鐘) performance style which was found in the text of the historical record. Through the analysis on Kangwon Sangkangrae, I found that it has musical characteristics as follows. The vocal range of type 1 and type 2 was mostly performed within Minor 7th and didn't exceed the perfect 8th. The melodic structure of type 1 starts with do'-la of naedeureum and ended with the melody which downscaled from do' and finalized from mi to la. Usually the mode was in menari-tori but at some lecture halls a few cases found to be upscaled from sol to la which differentiates it from the typical menari-tori of folk songs. Like the typical way of traditional rites, the singing was divided into two parts: the leading call and the following choral response. Most were sung to be one syllable on one or two tones or one syllable lasting for several tones and the musical forms were varied by musical pieces. Meantime, Sangkangrae at Haeinsa Temple was differed from that of the other temples in terms of ritual procedure and vocal style. It added Korean version of and the lead vocal skipped the first phrase of the Sasul. The melodic structure of Type 2 started with do'-la of naedeureum and was finalized as the same way of Type 1. The mode of was not the same as typical menari-tori but the Jeongrye(prostration) and Balweon(a great vow) were identical to the menari-tori of folk songs. The singing was done in two forms, solo and unison, and the lyric-attachment of Gesong was one syllable for one or two tones and that of Jeongrye and Balweon were one syllable for one or two tones + one syllable for several tones. The musical form of Jeongrye is A-B-C and A-C. Balweon didn't display a certain periodicity but still maintained sense of unity and formality through repetition of the finalizing melody.

Cloning of Low-molecular-weight Glutenin Subunit Genes and Identification of their Protein Products in Common Wheat (Triticum aestivum L.) (보통 밀에서 저분자글루테닌 유전자 클로닝 및 단백질 동정)

  • Lee, Jong-Yeol;Kim, Yeong-Tae;Kim, Bo-Mi;Lee, Jung-Hye;Lim, Sun-Hyung;Ha, Sun-Hwa;Ahn, Sang-Nag;Nam, Myung-Hee;Kim, Young-Mi
    • Korean Journal of Breeding Science
    • /
    • v.42 no.5
    • /
    • pp.547-554
    • /
    • 2010
  • Low-molecular-weight glutenin subunit (LMW-GS) in common wheat (Triticum aestivum L.) is important for quality processing of bread and noodles. The objectives of this study were to clarify the composition of LMW-GSs and to identify their corresponding proteins. Using LMW-GS specific primers we cloned and characterized 43 LMW-GS genes in the wheat cultivar 'Jokyoung'. Some of these genes contain polypeptides different in size due to the presence of various deletions or insertions within repetitive and glutamine-rich domains. The comparison of deduced amino acid sequence of the LMW-GS genes in Jokyoung with that of 12 groups LMW-GSs of wheat cultivar Norin 61 showed that the deduced amino acid sequences were nearly the same to LMW-GS groups of 1, 2, 3/4, 5, 7, 10 and 11. All LMW-GS genes contain eight cysteine residues, which are conserved among all of the typical LMW-GS sequences. The relative positions of cysteine residues are also conserved, except those of the first and seventh. Based on phylogenetic analysis, the 43 sequences with the same N-terminal and C-terminal amino acid sequences were clustered in the same group. To identify the proteins containing the corresponding amino acid sequences, we determined the N-terminal amino acid sequence of 7 spots of LMW-GSs of Jokyoung separated by two-dimensional gel electrophoresis (2DE). Of them, Glu-B3 (LMW-m and LMW-s) and Glu-D3 (LMW-m) were detected in two and three spots, respectively and the others were not clear. Collectively, we classified diverse LMW-GSs and identified their corresponding protein products. These results will be helpful in breeding programs for improvement of wheat flour quality.

The Study on 'characters made by Empress Wu Zetian' through The Avatamsaka-Sutra in ink on the white paper of the Shilla Period (신라(新羅) 백지묵서(白紙墨書) 화엄경(華嚴經)과 칙천무후자(則天武后字) 고찰(考察))

  • Park, Sang-Kuk
    • Korean Journal of Heritage: History & Science
    • /
    • v.37
    • /
    • pp.445-469
    • /
    • 2004
  • The Avatamsaka Sutra copied in ink on the white paper of Shilla Period is the oldest manuscript in korea. This Avatamsaka Sutra is volume 1-10 and 44-50 of the 80 volume's transcription. According to the postscript, written with 528 letters at the end of the volume 10 and 50, this sutra is made during A.D. 754-755, for six months by the order Master Yon-gi(綠起 法師) who founded Hwaumsa Temple(華嚴寺.) It explains the procedure of the ritual and production method of the sutra-copying, and also shows the 19 participants with their name, address, official title, and etc. When the sutra was founded, volume 1-10 were so congealed that we could not open the volumes. And volume 44-50 was prohibited to take photograph for preservation. According to the recent examination, it proved that this sutra is the treasure for the study of the characters made by Empress Wu Zetian(則天武后.) The characters made by Empress Wu Zetian(A.D. 625-705) are new shape of chinese characters which is different from the traditional characters. After the demise of the Queen, the characters were not used any more officially, but privately some people used the characters for personal tastes and interest. The characters in the sutra includes 512 characters of 13 kinds of Empress We Zetians'. Compared to the Tun-huang version of the sutra, this is far better treasure for the study of Empress We Zetians' characters in terms of the number of the character and the their use of frequency. The Avatamsaka Sutra of Shoso-in(正倉院) in japan copied in A.D. 768 does not use the Empress We Zetians' characters. In this respect, this Shilla Avatamsaka-Sutra is a unique one preserves the original forms of Chinese translation at that time.

Exploring an Integrated Garden City Theory Based on East Asian Garden Culture - Centering on Community and Integration - (동아시아 정원문화에 기반한 통합적 정원도시론의 모색 - 공동체성과 통합성을 중심으로 -)

  • Ahn, Myung-June
    • Journal of the Korean Institute of Traditional Landscape Architecture
    • /
    • v.41 no.3
    • /
    • pp.13-26
    • /
    • 2023
  • Landscapes and gardens have emerged as an important medium of practice in contemporary cities. Among them, this paper examines the city through the frame of gardens. This is because gardens are being reconceptualized as a medium of activity for urban residents and have become an important subject of action in urban regeneration and the creation of urban villages. From this perspective, this paper examines and proposes an "integrated garden city theory" as a landscape theory suitable for the contemporary era by focusing on the urban structure and the behavior of urban residents through the medium of gardens, as well as the process and results. This is both a process and a result of looking back at the evolution of landscape for over a century and rethinking the identity of landscape. We first examined garden city theory, noting that Ebenezer Howard and Frederick Law Olmsted's positions on the relationship between gardens and cities were not so different, and that "working and responsive landscapes" were fundamental to cities and the beginning of landscape theory. We also examine how their ideals have not been fully realized in cities over the past century, but the prototype of gardens based on traditional garden culture is now being formed in East Asian cities, and the evolution of landscape theory in response. The conclusion is that a new version of the garden concept should be reestablished as a living infrastructure in our cities, and a new garden city theory is needed to make it work. To this end, each chapter examines three arguments, as follows First, the values of gardens and East Asian garden cultures in contemporary cities are shaped by the themes of community and integrity. Second, Korean communality, represented by apartments, is expressed through gardening and requires the reconciliation of city and life and the role of landscape architecture as a specialized field to support it. Third, we examine and consider an integrated garden city theory as a theory of practice in which city-based, everyday life, and garden mediums, i.e., city, life, and garden, are organic, based on an oriental view of nature. As a result, it is confirmed that contemporary gardens and cities are looking for important elements and values that still need to be rediscovered in East Asian landscape and garden cultures. Although the proposal of an integrated garden city theory cannot guarantee the continuation of landscaping, it can be an opportunity for all fields related to cities, not just landscaping, to collaborate and consider garden cities. Through this, it is hoped that "the concept of garden and city suitable for metropolitan or dense cities, ways to spread and support garden culture based on community, evolution of landscape theory/design theory suitable for lifestyle and terrain conditions, search for sustainable/resilient garden city theory that can respond to climate change, and establishing a new role for landscape in the 21st century" will be seriously considered.

A Review Examining the Dating, Analysis of the Painting Style, Identification of the Painter, and Investigation of the Documentary Records of Samsaebulhoedo at Yongjusa Temple (용주사(龍珠寺) <삼세불회도(三世佛會圖)> 연구의 연대 추정과 양식 분석, 작가 비정, 문헌 해석의 검토)

  • Kang, Kwanshik
    • MISULJARYO - National Museum of Korea Art Journal
    • /
    • v.97
    • /
    • pp.14-54
    • /
    • 2020
  • The overall study of Samsaebulhoedo (painting of the Assembly of Buddhas of Three Ages) at Yongjusa Temple has focused on dating it, analyzing the painting style, identifying its painter, and scrutinizing the related documents. However, its greater coherence could be achieved through additional support from empirical evidence and logical consistency. Recent studies on Samsaebulhoedo at Yongjusa Temple that postulate that the painting could have been produced by a monk-painter in the late nineteenth century and that an original version produced in 1790 could have been retouched by a painter in the 1920s using a Western painting style lack such empirical proof and logic. Although King Jeongjo's son was not yet installed as crown prince, the Samsaebulhoedo at Yongjusa Temple contained a conventional written prayer wishing for a long life for the king, queen, and crown prince: "May his majesty the King live long / May her majesty the Queen live long / May his highness the Crown Prince live long" (主上殿下壽萬歲, 王妃殿下壽萬歲, 世子邸下壽萬歲). Later, this phrase was erased using cinnabar and revised to include unusual content in an exceptional order: "May his majesty the King live long / May his highness the King's Affectionate Mother (Jagung) live long / May her majesty the Queen live long / May his highness the Crown Prince live long" (主上殿下壽萬歲, 慈宮邸下壽萬歲, 王妃殿下壽萬歲, 世子邸下壽萬歲). A comprehensive comparison of the formats and contents in written prayers found on late Joseon Buddhist paintings and a careful analysis of royal liturgy during the reign of King Jeongjo reveal Samsaebulhoedo at Yongjusa Temple to be an original version produced at the time of the founding of Yongjusa Temple in 1790. According to a comparative analysis of formats, iconography, styles, aesthetic sensibilities, and techniques found in Buddhist paintings and paintings by Joseon court painters from the eighteenth and nineteenth centuries, Samsaebulhoedo at Yongjusa Temple bears features characteristic of paintings produced around 1790, which corresponds to the result of analysis on the written prayer. Buddhist paintings created up to the early eighteenth century show deities with their sizes determined by their religious status and a two-dimensional conceptual composition based on the traditional perspective of depicting close objects in the lower section and distant objects above. This Samsaebulhoedo, however, systematically places the Buddhist deities within a threedimensional space constructed by applying a linear perspective. Through the extensive employment of chiaroscuro as found in Western painting, it expresses white highlights and shadows, evoking a feeling that the magnificent world of the Buddhas of the Three Ages actually unfolds in front of viewers. Since the inner order of a linear perspective and the outer illusion of chiaroscuro shading are intimately related to each other, it is difficult to believe that the white highlights were a later addition. Moreover, the creative convergence of highly-developed Western painting style and techniques that is on display in this Samsaebulhoedo could only have been achieved by late-Joseon court painters working during the reign of King Jeongjo, including Kim Hongdo, Yi Myeong-gi, and Kim Deuksin. Deungun, the head monk of Yongjusa Temple, wrote Yongjusa sajeok (History of Yongjusa Temple) by compiling the historical records on the temple that had been transmitted since its founding. In Yongjusa sajeok, Deungun recorded that Kim Hongdo painted Samsaebulhoedo as if it were a historical fact. The Joseon royal court's official records, Ilseongnok (Daily Records of the Royal Court and Important Officials) and Suwonbu jiryeong deungnok (Suwon Construction Records), indicate that Kim Hongdo, Yi Myeong-gi, and Kim Deuksin all served as a supervisor (gamdong) for the production of Buddhist paintings. Since within Joseon's hierarchical administrative system it was considered improper to allow court painters of government position to create Buddhist paintings which had previously been produced by monk-painters, they were appointed as gamdong in name only to avoid a political liability. In reality, court painters were ordered to create Buddhist paintings. During their reigns, King Yeongjo and King Jeongjo summoned the literati painters Jo Yeongseok and Kang Sehwang to serve as gamdong for the production of royal portraits and requested that they paint these portraits as well. Thus, the boundary between the concept of supervision and that of painting occasionally blurred. Supervision did not completely preclude painting, and a gamdong could also serve as a painter. In this light, the historical records in Yongjusa sajeok are not inconsistent with those in Ilseongnok, Suwonbu jiryeong deungnok, and a prayer written by Hwang Deok-sun, which was found inside the canopy in Daeungjeon Hall at Yongjusa Temple. These records provided the same content in different forms as required for their purposes and according to the context. This approach to the Samsaebulhoedo at Yongjusa Temple will lead to a more coherent explanation of dating the painting, analyzing its style, identifying its painter, and interpreting the relevant documents based on empirical grounds and logical consistency.

A Comparative Study of Subset Construction Methods in OSEM Algorithms using Simulated Projection Data of Compton Camera (모사된 컴프턴 카메라 투사데이터의 재구성을 위한 OSEM 알고리즘의 부분집합 구성법 비교 연구)

  • Kim, Soo-Mee;Lee, Jae-Sung;Lee, Mi-No;Lee, Ju-Hahn;Kim, Joong-Hyun;Kim, Chan-Hyeong;Lee, Chun-Sik;Lee, Dong-Soo;Lee, Soo-Jin
    • Nuclear Medicine and Molecular Imaging
    • /
    • v.41 no.3
    • /
    • pp.234-240
    • /
    • 2007
  • Purpose: In this study we propose a block-iterative method for reconstructing Compton scattered data. This study shows that the well-known expectation maximization (EM) approach along with its accelerated version based on the ordered subsets principle can be applied to the problem of image reconstruction for Compton camera. This study also compares several methods of constructing subsets for optimal performance of our algorithms. Materials and Methods: Three reconstruction algorithms were implemented; simple backprojection (SBP), EM, and ordered subset EM (OSEM). For OSEM, the projection data were grouped into subsets in a predefined order. Three different schemes for choosing nonoverlapping subsets were considered; scatter angle-based subsets, detector position-based subsets, and both scatter angle- and detector position-based subsets. EM and OSEM with 16 subsets were performed with 64 and 4 iterations, respectively. The performance of each algorithm was evaluated in terms of computation time and normalized mean-squared error. Results: Both EM and OSEM clearly outperformed SBP in all aspects of accuracy. The OSEM with 16 subsets and 4 iterations, which is equivalent to the standard EM with 64 iterations, was approximately 14 times faster in computation time than the standard EM. In OSEM, all of the three schemes for choosing subsets yielded similar results in computation time as well as normalized mean-squared error. Conclusion: Our results show that the OSEM algorithm, which have proven useful in emission tomography, can also be applied to the problem of image reconstruction for Compton camera. With properly chosen subset construction methods and moderate numbers of subsets, our OSEM algorithm significantly improves the computational efficiency while keeping the original quality of the standard EM reconstruction. The OSEM algorithm with scatter angle- and detector position-based subsets is most available.