• Title/Summary/Keyword: pointing system

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Industry-Academy Collaboration as National Innovation System (우리나라 산학협력의 현황과 과제;국가혁신시스템 관점)

  • Sohn, Byung-Ho;Lee, Byung-Hyun;Jang, Ji-Ho
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.1 no.1
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    • pp.23-52
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    • 2006
  • Industry-academy Collaboration alms to produce synergy-empowerment through co-opt between university and business within R&D and human resource management. The lack of indigenous R&D capabilities makes Korean small businesses not have sustainable competitive advantages. While the Korean government has increased the budgetary supports on small businesses since the late 1990s to enhance technological capabilities of small businesses, the competitiveness gap between large and small firms has been widened. The alternative for the government support is considered as active industry-academy collaboration. After exploring various policy measures for the collaboration with classifying them and pointing out their problems from a technological innovation perspective, this study shows the more expected roles of the collaboration to be a catalyst coordinating the R&D activities among the local small businesses, local universities, and public research institutes. Based upon the analyses, this study suggests several policy alternatives to facilitate the technological innovations of small businesses in the regional innovation clusters.

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DEVELOPMENT OF THE MECHANICAL STRUCTURE OF THE MIRIS SOC (MIRIS 우주관측카메라의 기계부 개발)

  • Moon, B.K.;Jeong, W.S.;Cha, S.M.;Ree, C.H.;Park, S.J.;Lee, D.H.;Yuk, I.S.;Park, Y.S.;Park, J.H.;Nam, U.W.;Matsumoto, Toshio;Yoshida, Seiji;Yang, S.C.;Lee, S.H.;Rhee, S.W.;Han, W.
    • Publications of The Korean Astronomical Society
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    • v.24 no.1
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    • pp.53-64
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    • 2009
  • MIRIS is the main payload of the STSAT-3 (Science and Technology Satellite 3) and the first infrared space telescope for astronomical observation in Korea. MIRIS space observation camera (SOC) covers the observation wavelength from $0.9{\mu}m$ to $2.0{\mu}m$ with a wide field of view $3.67^{\circ}\times3.67^{\circ}$. The PICNIC HgCdTe detector in a cold box is cooled down below 100K by a micro Stirling cooler of which cooling capacity is 220mW at 77K. MIRIS SOC adopts passive cooling technique to chill the telescope below 200 K by pointing to the deep space (3K). The cooling mechanism employs a radiator, a Winston cone baffle, a thermal shield, MLI (Multi Layer Insulation) of 30 layers, and GFRP (Glass Fiber Reinforced Plastic) pipe support in the system. Optomechanical analysis was made in order to estimate and compensate possible stresses from the thermal contraction of mounting parts at cryogenic temperatures. Finite Element Analysis (FEA) of mechanical structure was also conducted to ensure safety and stability in launching environments and in orbit. MIRIS SOC will mainly perform Galactic plane survey with narrow band filters (Pa $\alpha$ and Pa $\alpha$ continuum) and CIB (Cosmic Infrared Background) observation with wide band filters (I and H) driven by a cryogenic stepping motor.

Remote Sensing of Atmospheric Trace Species using Multi Axis Differential Optical Absorption Spectroscopy (Multi Axis DOAS를 이용한 대기미량 물질 원격 측정)

  • Lee Chul-Kyu;Kim Young-Joon
    • Korean Journal of Remote Sensing
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    • v.22 no.2
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    • pp.141-151
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    • 2006
  • UV-visible absorption measurement techniques using several horizone viewing directions in addition to the traditional zenith-sky pointing have been recently developed in ground-based remote sensing of atmospheric constituents. The spatial distribution of various trace gases close to the instrument can be derived by combing several viewing directions. Multi-axis differential optical absorption spectroscopy (MAX-DOAS) technique, one of the remote sensing techniques for air quality measurements, uses the scattered sunlight as a light source and measures it at various elevation angles (corresponding to the viewing directions) by sequential scanning with a stepper motor. A MAX-DOAS system developed by GIST/ADEMRC has been applied to measuring trace gases in urban air and plumes of the volcano and fossil fuel power plant in January, May, and October 2004, respectively. MAX-DOAS spectra were analyzed to identify and quantify $SO_2,\;NO_2,\;BrO,\;and\;O_4$ (based on Slant Column Densities, SCD) in the urban air, volcanic plume, and fossil fuel power plant utilizing theirs specific structured absorption features in the UV-visible region. Vertical scan through the multiple elevation angles was performed at different directions perpendicular to the plume dispersion to retrieve cross-sectional distribution of $SO_2\;or\;NO_2$ in the plumes of the volcano and fossil fuel power plant. Based on the estimated cross sections of the plumes the mixing ratios were estimated to 580 $SO_2$ ppbv in the volcanic Plume, and 337 $NO_2\;and\;227\;SO_2$ ppbv in the plume of the fossil fuel power plant, respectively.

Numerical Modeling of Optical Energy Transfer Based on Coherent Beam Combination under Turbulent Atmospheric Conditions (대기 외란 상황에서 결맞음 빔결합을 통한 광학 에너지의 전달 방법 수치 모델링)

  • Na, Jeongkyun;Kim, Byungho;Cha, Hyesun;Jeong, Yoonchan
    • Korean Journal of Optics and Photonics
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    • v.31 no.6
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    • pp.274-280
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    • 2020
  • In this paper, the effect of atmospheric turbulence is numerically modeled and analyzed via a phase-screen model, in regard to long-range optical energy transfer using coherent beam combination. The coherent-beam-combination system consists of three channel beams pointing at a target at a distance of 1-2 km. The phase and propagation direction of each channel beam are assumed to be corrected in an appropriate manner, and the atmospheric turbulence that occurs while the beam propagates through free space is quantified with a phase-screen model. The phase screen is statistically generated and constructed within the range of fluctuations of the structure constant Cn2 from 10-15 to 10-13 [m-2/3]. Particularly, in this discussion the shape, distortion, and combining efficiency of the 3-channel combined beam are calculated at the target plane by varying the structure constant used in the phase-screen model, and the effect of atmospheric turbulence on beam-combination efficiency is analyzed. Analysis with this numerical model verifies that when coherent beam combination is used for long-range optical energy transfer, the received power at the target can be at least three times the power obtainable by incoherent beam combination, even for maximal atmospheric fluctuation within the given range. This numerical model is expected to be effective for analyzing the effects of various types of atmospheric-turbulence conditions and beam-combination methods when simulating long-range optical energy transfer.

Seeking an Establishment of Structure in the Big-gut, Jaindanoje (자인단오제 큰굿의 구조 정립 모색)

  • Hong, Teahan
    • (The) Research of the performance art and culture
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    • no.19
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    • pp.35-60
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    • 2009
  • I insisted that the structure should be set newly, pointing out problems in a structure of the big gut, Jain dano je in this paper. Although, the big gut is playing now in Jain dano je, the features of gut geo-ri are vague ; that's why gut geo-ri and performances are entangled. Therefore, the gut geori showing strange structures not fitted with korean shamanist custom is playing these days like Pawangbyeolhui and Eoudong geori. The detailed procedure is also awkward. It is mixed with aspects of shaman custom in each region, instead showing features of regions. What's more, it became a dance drama, not gut geo-ri with several shamans dancing in a gut. Overcoming these problems, the big gut will be a cultural asset. Therefore, when considering the structure of korean gut, we will fit the order of gut geo-ri into the system of divine spirits keeping a plot-opening, developing and closing. It should be a gut geori-oriented play with only gut geo-ri things. Gut should be gone forward main shaman-oriented gut, setting up a main shaman who takes charge of each gut geo-ri. We should find out a new shaman who knows gut of Gyeong sang province well, if shaman who now takes charge of it has a problem. The big gut of Jain dano je became a part of intangible cultural assets. The performance is not a subject of curiosity and people's interests any more as it was in a past. It should be a traditional performance of representing our traditional culture. We should reorganize an epochal gut geo-ri after reexamining gut geo-ri which has played so far.

Dispute of Part-Whole Representation in Conceptual Modeling (부분-전체 관계에 관한 개념적 모델링의 논의에 관하여)

  • Kim, Taekyung;Park, Jinsoo;Rho, Sangkyu
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.97-116
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    • 2012
  • Conceptual modeling is an important step for successful system development. It helps system designers and business practitioners share the same view on domain knowledge. If the work is successful, a result of conceptual modeling can be beneficial in increasing productivity and reducing failures. However, the value of conceptual modeling is unlikely to be evaluated uniformly because we are lack of agreement on how to elicit concepts and how to represent those with conceptual modeling constructs. Especially, designing relationships between components, also known as part-whole relationships, have been regarded as complicated work. The recent study, "Representing Part-Whole Relations in Conceptual Modeling : An Empirical Evaluation" (Shanks et al., 2008), published in MIS Quarterly, can be regarded as one of positive efforts. Not only the study is one of few attempts of trying to clarify how to select modeling alternatives in part-whole design, but also it shows results based on an empirical experiment. Shanks et al. argue that there are two modeling alternatives to represent part-whole relationships : an implicit representation and an explicit one. By conducting an experiment, they insist that the explicit representation increases the value of a conceptual model. Moreover, Shanks et al. justify their findings by citing the BWW ontology. Recently, the study from Shanks et al. faces criticism. Allen and March (2012) argue that Shanks et al.'s experiment is lack of validity and reliability since the experimental setting suffers from error-prone and self-defensive design. They point out that the experiment is intentionally fabricated to support the idea, as such that using concrete UML concepts results in positive results in understanding models. Additionally, Allen and March add that the experiment failed to consider boundary conditions; thus reducing credibility. Shanks and Weber (2012) contradict flatly the argument suggested by Allen and March (2012). To defend, they posit the BWW ontology is righteously applied in supporting the research. Moreover, the experiment, they insist, can be fairly acceptable. Therefore, Shanks and Weber argue that Allen and March distort the true value of Shanks et al. by pointing out minor limitations. In this study, we try to investigate the dispute around Shanks et al. in order to answer to the following question : "What is the proper value of the study conducted by Shanks et al.?" More profoundly, we question whether or not using the BWW ontology can be the only viable option of exploring better conceptual modeling methods and procedures. To understand key issues around the dispute, first we reviewed previous studies relating to the BWW ontology. We critically reviewed both of Shanks and Weber and Allen and March. With those findings, we further discuss theories on part-whole (or part-of) relationships that are rarely treated in the dispute. As a result, we found three additional evidences that are not sufficiently covered by the dispute. The main focus of the dispute is on the errors of experimental methods: Shanks et al. did not use Bunge's Ontology properly; the refutation of a paradigm shift is lack of concrete, logical rationale; the conceptualization on part-whole relations should be reformed. Conclusively, Allen and March indicate properly issues that weaken the value of Shanks et al. In general, their criticism is reasonable; however, they do not provide sufficient answers how to anchor future studies on part-whole relationships. We argue that the use of the BWW ontology should be rigorously evaluated by its original philosophical rationales surrounding part-whole existence. Moreover, conceptual modeling on the part-whole phenomena should be investigated with more plentiful lens of alternative theories. The criticism on Shanks et al. should not be regarded as a contradiction on evaluating modeling methods of alternative part-whole representations. To the contrary, it should be viewed as a call for research on usable and useful approaches to increase value of conceptual modeling.

King Jeongjo's recognition on Neo-Confucian literati and it's historical meaning (정조(正祖)의 사대부(士大夫) 인식(認識)과 그 특징(特徵))

  • Park, Sung-soon
    • (The)Study of the Eastern Classic
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    • no.32
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    • pp.103-128
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    • 2008
  • King Jeongjo had lost his father, Sado-Seja(Prince Sado) by Noron(Older Faction). Especially those who tried to kill Sado-Seja and king Jeongjo consisted of king's family-in-law of king Youngjo and Sado-Seja. Therefore king Jeongjo's first goal was to strengthen his kingship than other things because he could gain the throne overcoming the strong hinderance of Noron and king's family-in-law. King Jeongjo requested his subjects to be "Kukbyon-In"(國邊人: a person for king) pointing out the harm of the king's family-in-law and "Tangpyong-Dang"(蕩平黨: the strongest faction consisted under the rule of king Youngjo). For the purpose, king Jeongjo built up "Gyujang-Gak". Gyujang-Gak was spoken to contain and protect the writings of earlier kings superficially, but in reality, it was an apparatus to gain and train the friendly subjects for king Jeongjo. Like that, it was the most important for king Jeongjo to suppress the king's family-in-low and to win Neo-Confucian lterati over to himself's side. Until now, the politics of Joseon Dynasty had been mainly explained on the point of view of "Seonghak-Non"(聖學論). "Seonghak-Non" means that Neo-Confucian lterati were treated as real hero, not kings in the political space of Joseon Dynasty and the role of factions were recognized important. But king Jeongjo denied these ideological stream and tried to change that political system. King Jeongjo wanted to strengthen the throne through the method which insisted the king as a hero in politics. For the purpose, king Jeongjo criticized the Neo-Confucian literati's viewpoint about politics and learning at that time and anticipated to be sole leader of politics and learning on that critique. King Jeongjo aimed to destroy the dignity of "Salim"(山林: Neo-Confucian Sages) with attacking their wrong behaviors. King Jeongjo also criticized the period of king Injo when the regime of "Sarim"(士林: pure Neo-Confucian lterati) faction fully appeared as the starting period when the factional harms were getting worse. King Jeongjo wanted to previously block the oppositions to win subjects over to himself's side with criticizing the period of king Injo and to take away the initiative from his opponents with insisting "Salim-Muyongnon"(山林無用論: a theory ignoring Neo-Confucian Sages). King Jeongjo's critique was not limited just on the system of factional politics. "Seonghak-Non" eventually took root in Neo-Confucianism. Therefore king Jeongjo criticized Neo-Confucianism. He insisted that the essence of Chinese Classics was pragmatical learning, not Neo-Confucianism. Through that critique, king Jeongjo aimed to destroy the ideological base of his opponents. However, king Jeongjo failed to be a sole leader of his subjects in the both boundaries of politics and learning even though he criticized the Neo-Confucian lterati's viewpoint about politics and learning. Because he abruptly died leaving his reformational scheme behind as well as his loyal subjects guarding himself against Noron Byeok-Pa(老論 ?派: the opposing party in Older Faction) were gone behind himself. The politics of Joseon Dynasty returned to more powerful politics for king's family-in-law after king Jeongjo's death.

A Mobile Landmarks Guide : Outdoor Augmented Reality based on LOD and Contextual Device (모바일 랜드마크 가이드 : LOD와 문맥적 장치 기반의 실외 증강현실)

  • Zhao, Bi-Cheng;Rosli, Ahmad Nurzid;Jang, Chol-Hee;Lee, Kee-Sung;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • v.18 no.1
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    • pp.1-21
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    • 2012
  • In recent years, mobile phone has experienced an extremely fast evolution. It is equipped with high-quality color displays, high resolution cameras, and real-time accelerated 3D graphics. In addition, some other features are includes GPS sensor and Digital Compass, etc. This evolution advent significantly helps the application developers to use the power of smart-phones, to create a rich environment that offers a wide range of services and exciting possibilities. To date mobile AR in outdoor research there are many popular location-based AR services, such Layar and Wikitude. These systems have big limitation the AR contents hardly overlaid on the real target. Another research is context-based AR services using image recognition and tracking. The AR contents are precisely overlaid on the real target. But the real-time performance is restricted by the retrieval time and hardly implement in large scale area. In our work, we exploit to combine advantages of location-based AR with context-based AR. The system can easily find out surrounding landmarks first and then do the recognition and tracking with them. The proposed system mainly consists of two major parts-landmark browsing module and annotation module. In landmark browsing module, user can view an augmented virtual information (information media), such as text, picture and video on their smart-phone viewfinder, when they pointing out their smart-phone to a certain building or landmark. For this, landmark recognition technique is applied in this work. SURF point-based features are used in the matching process due to their robustness. To ensure the image retrieval and matching processes is fast enough for real time tracking, we exploit the contextual device (GPS and digital compass) information. This is necessary to select the nearest and pointed orientation landmarks from the database. The queried image is only matched with this selected data. Therefore, the speed for matching will be significantly increased. Secondly is the annotation module. Instead of viewing only the augmented information media, user can create virtual annotation based on linked data. Having to know a full knowledge about the landmark, are not necessary required. They can simply look for the appropriate topic by searching it with a keyword in linked data. With this, it helps the system to find out target URI in order to generate correct AR contents. On the other hand, in order to recognize target landmarks, images of selected building or landmark are captured from different angle and distance. This procedure looks like a similar processing of building a connection between the real building and the virtual information existed in the Linked Open Data. In our experiments, search range in the database is reduced by clustering images into groups according to their coordinates. A Grid-base clustering method and user location information are used to restrict the retrieval range. Comparing the existed research using cluster and GPS information the retrieval time is around 70~80ms. Experiment results show our approach the retrieval time reduces to around 18~20ms in average. Therefore the totally processing time is reduced from 490~540ms to 438~480ms. The performance improvement will be more obvious when the database growing. It demonstrates the proposed system is efficient and robust in many cases.

Operative Challenges in Releasing Administrative Information and Records (행정정보 및 보존기록물 공개의 운영과제)

  • Lee, Won-Kyu
    • The Korean Journal of Archival Studies
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    • no.12
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    • pp.81-135
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    • 2005
  • The release of administrative information has been the challenge of our age following the maturation of democratic ideology in our society. However, differences of opinion and conflict still exist between the government and private sectors regarding the issue, and it seems that the technical and policy-related insufficiencies of information and record management that actually operate the release of information are the main causes. From the perspective of records management, records or information are variable in their nature, value, and influence during their life span. The most controversial issue is the records and information in the current stage of carrying out business activities. This is because the records and information pertaining to finished business are but evidence to ascertain the past, and have only a limited relationship to the ideal of the 'democratic participation' by citizens in activities of the public sector. The current information release policies are helpless against the 'absence of information,' or incomplete records, but such weakness can be supplemented by enforcing record management policies that make obligatory the recording of all details of business activities. In addition, it is understood that the installation of 'document offices("Jaryogwan")' that can manage each organization's information and records will be an important starting point to integrate the release, management, and preservation of information and records. Nevertheless, it seems that the concept of 'release' in information release policies refers not to free use by all citizens but is limited to the 'provision' of records according to public requests, and the concept of 'confidential' refers not to treating documents with total secrecy but varies according to the particulars of each situation, making the actual practice of information release difficult. To solve such problems, it is absolutely necessary to collect the opinions of various constituents associated with the recorded information in question, and to effectively mediate the collective opinions and the information release requests coming from applicants, to carry out the business more practically. Especially crucial is the management of the process by which the nature and influence of recorded information changes, so that information which has to be confidential at first may become available for inquiry and use over time through appropriate procedures. Such processes are also part of the duties that record management, which is in charge of the entire life span of documents, must perform. All created records will be captured within a record management system, and the record creation data thus collected will be used as a guide for inquiry and usage. With 'document offices(Jaryogwan)' and 'archives' controlling the entire life span of records, the release of information will become simpler and more widespread. It is undesirable to try to control only through information release policies those records the nature of which has changed because, unlike the ones still in the early stages of their life span and can directly influence business activities, their work has finished, and they have become historical records or evidences pointing to the truth of past events. Even in the past, when there existed no formal policy regarding the release of administrative information, the access and use of archival records were permitted. A more active and expanded approach must be taken regarding the 'usage' of archival records. If the key factor regarding 'release' lies in the provision of information, the key factor regarding 'usage' lies in the quality and level of the service provided. The full-scale usage of archival records must be preceded by the release of such records, and accordingly, a thorough analysis of the nature, content, and value of the records and their changes must be implemented to guarantee the release of information before their use is requested. That must become a central task of document offices and "Today's information" will soon become "yesterday's records," and the "reality" of today will become "history" of the past. The policies of information release and record management share information records as their common objective. As they have a mutual relationship that is supplementary and leads toward perfection, the two policies must both be differentiated and integrated with each another. It is hoped that the policies and business activities of record management will soon become normalized and reformed for effective and fair release of information.

A Ranking Algorithm for Semantic Web Resources: A Class-oriented Approach (시맨틱 웹 자원의 랭킹을 위한 알고리즘: 클래스중심 접근방법)

  • Rho, Sang-Kyu;Park, Hyun-Jung;Park, Jin-Soo
    • Asia pacific journal of information systems
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    • v.17 no.4
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    • pp.31-59
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    • 2007
  • We frequently use search engines to find relevant information in the Web but still end up with too much information. In order to solve this problem of information overload, ranking algorithms have been applied to various domains. As more information will be available in the future, effectively and efficiently ranking search results will become more critical. In this paper, we propose a ranking algorithm for the Semantic Web resources, specifically RDF resources. Traditionally, the importance of a particular Web page is estimated based on the number of key words found in the page, which is subject to manipulation. In contrast, link analysis methods such as Google's PageRank capitalize on the information which is inherent in the link structure of the Web graph. PageRank considers a certain page highly important if it is referred to by many other pages. The degree of the importance also increases if the importance of the referring pages is high. Kleinberg's algorithm is another link-structure based ranking algorithm for Web pages. Unlike PageRank, Kleinberg's algorithm utilizes two kinds of scores: the authority score and the hub score. If a page has a high authority score, it is an authority on a given topic and many pages refer to it. A page with a high hub score links to many authoritative pages. As mentioned above, the link-structure based ranking method has been playing an essential role in World Wide Web(WWW), and nowadays, many people recognize the effectiveness and efficiency of it. On the other hand, as Resource Description Framework(RDF) data model forms the foundation of the Semantic Web, any information in the Semantic Web can be expressed with RDF graph, making the ranking algorithm for RDF knowledge bases greatly important. The RDF graph consists of nodes and directional links similar to the Web graph. As a result, the link-structure based ranking method seems to be highly applicable to ranking the Semantic Web resources. However, the information space of the Semantic Web is more complex than that of WWW. For instance, WWW can be considered as one huge class, i.e., a collection of Web pages, which has only a recursive property, i.e., a 'refers to' property corresponding to the hyperlinks. However, the Semantic Web encompasses various kinds of classes and properties, and consequently, ranking methods used in WWW should be modified to reflect the complexity of the information space in the Semantic Web. Previous research addressed the ranking problem of query results retrieved from RDF knowledge bases. Mukherjea and Bamba modified Kleinberg's algorithm in order to apply their algorithm to rank the Semantic Web resources. They defined the objectivity score and the subjectivity score of a resource, which correspond to the authority score and the hub score of Kleinberg's, respectively. They concentrated on the diversity of properties and introduced property weights to control the influence of a resource on another resource depending on the characteristic of the property linking the two resources. A node with a high objectivity score becomes the object of many RDF triples, and a node with a high subjectivity score becomes the subject of many RDF triples. They developed several kinds of Semantic Web systems in order to validate their technique and showed some experimental results verifying the applicability of their method to the Semantic Web. Despite their efforts, however, there remained some limitations which they reported in their paper. First, their algorithm is useful only when a Semantic Web system represents most of the knowledge pertaining to a certain domain. In other words, the ratio of links to nodes should be high, or overall resources should be described in detail, to a certain degree for their algorithm to properly work. Second, a Tightly-Knit Community(TKC) effect, the phenomenon that pages which are less important but yet densely connected have higher scores than the ones that are more important but sparsely connected, remains as problematic. Third, a resource may have a high score, not because it is actually important, but simply because it is very common and as a consequence it has many links pointing to it. In this paper, we examine such ranking problems from a novel perspective and propose a new algorithm which can solve the problems under the previous studies. Our proposed method is based on a class-oriented approach. In contrast to the predicate-oriented approach entertained by the previous research, a user, under our approach, determines the weights of a property by comparing its relative significance to the other properties when evaluating the importance of resources in a specific class. This approach stems from the idea that most queries are supposed to find resources belonging to the same class in the Semantic Web, which consists of many heterogeneous classes in RDF Schema. This approach closely reflects the way that people, in the real world, evaluate something, and will turn out to be superior to the predicate-oriented approach for the Semantic Web. Our proposed algorithm can resolve the TKC(Tightly Knit Community) effect, and further can shed lights on other limitations posed by the previous research. In addition, we propose two ways to incorporate data-type properties which have not been employed even in the case when they have some significance on the resource importance. We designed an experiment to show the effectiveness of our proposed algorithm and the validity of ranking results, which was not tried ever in previous research. We also conducted a comprehensive mathematical analysis, which was overlooked in previous research. The mathematical analysis enabled us to simplify the calculation procedure. Finally, we summarize our experimental results and discuss further research issues.