• Title/Summary/Keyword: Problem-finding

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MPSoC Design Space Exploration Based on Static Analysis of Process Network Model (프로세스 네트워크 모델의 정적 분석에 기반을 둔 다중 프로세서 시스템 온 칩 설계 공간 탐색)

  • Ahn, Yong-Jin;Choi, Ki-Young
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.44 no.10
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    • pp.7-16
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    • 2007
  • In this paper, we introduce a new design environment for efficient multiprocessor system-on-chip design space exploration. The design environment takes a process network model as input system specification. The process network model has been widely used for modeling signal processing applications because of its excellent modeling power. However, it has limitation in predictability, which could cause severe problem for real time systems. This paper proposes a new approach that enables static analysis of a process network model by converting it to a hierarchical synchronous dataflow model. For efficient design space exploration in the early design step, mapping application to target architectures has been a crucial part for finding better solution. In this paper, we propose an efficient mapping algorithm. Our mapping algorithm supports both single bus architecture and multiple bus architecture. In the experiments, we show that the automatic conversion approach of the process network model for static analysis is performed successfully for several signal processing applications, and show the effectiveness of our mapping algorithm by comparing it with previous approaches.

Flexible Intelligent Exit Sign Management of Cloud-Connected Buildings

  • Lee, Minwoo;Mariappan, Vinayagam;Lee, Junghoon;Cho, Juphil;Cha, Jaesang
    • International Journal of Advanced Culture Technology
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    • v.5 no.1
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    • pp.58-63
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    • 2017
  • Emergencies and disasters can happen any time without any warning, and things can change and escalate very quickly, and often it is swift and decisive actions that make all the difference. It is a responsibility of the building facility management to ensure that a proven evacuation plan in place to cover various worst scenario to handled automatically inside the facility. To mapping out optimal safe escape routes is a straightforward undertaking, but does not necessarily guarantee residents the highest level of protection. The emergency evacuation navigation approach is a state-of-the-art that designed to evacuate human livings during an emergencies based on real-time decisions using live sensory data with pre-defined optimum path finding algorithm. The poor decision on causalities and guidance may apparently end the evacuation process and cannot then be remedied. This paper propose a cloud connected emergency evacuation system model to react dynamically to changes in the environment in emergency for safest emergency evacuation using IoT based emergency exit sign system. In the previous researches shows that the performance of optimal routing algorithms for evacuation purposes are more sensitive to the initial distribution of evacuees, the occupancy levels, and the type and level of emergency situations. The heuristic-based evacuees routing algorithms have a problem with the choice of certain parameters which causes evacuation process in real-time. Therefore, this paper proposes an evacuee routing algorithm that optimizes evacuation by making using high computational power of cloud servers. The proposed algorithm is evaluated via a cloud-based simulator with different "simulated casualties" are then re-routed using a Dijkstra's algorithm to obtain new safe emergency evacuation paths against guiding evacuees with a predetermined routing algorithm for them to emergency exits. The performance of proposed approach can be iterated as long as corrective action is still possible and give safe evacuation paths and dynamically configure the emergency exit signs to react for real-time instantaneous safe evacuation guidance.

The κ-Fermat's Integer Factorization Algorithm (κ-페르마 소인수분해 알고리즘)

  • Choi, Myeong-Bok;Lee, Sang-Un
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.11 no.4
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    • pp.157-164
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    • 2011
  • It is very difficult problem to factorize composite number. Integer factorization algorithms, for the most part, find ($a,b$) that is congruence of squares ($a^2{\equiv}b^2$(mode $n$)) with using factoring(factor base, B) and get the result, $p=GCD(a-b,n)$, $q=GCD(a+b,n)$ with taking the greatest common divisor of Euclid based on the formula $a^2-b^2=(a-b)(a+b)$. The efficiency of these algorithms hangs on finding ($a,b$). Fermat's algorithm that is base of congruence of squares finds $a^2-b^2=n$. This paper proposes the method to find $a^2-b^2=kn$, ($k=1,2,{\cdots}$). It is supposed $b_1$=0 or 5 to be surely, and b is a double number. First, the proposed method decides $k$ by getting kn that satisfies $b_1=0$ and $b_1=5$ about $n_2n_1$. Second, it decides $a_2a_1$ that satisfies $a^2-b^2=kn$. Third, it figures out ($a,b$) from $a^2-b^2=kn$ about $a_2a_1$ as deciding $\sqrt{kn}$ < $a$ < $\sqrt{(k+1)n}$ that is in $kn$ < $a^2$ < $(k+1)n$. The proposed algorithm is much more effective in comparison with the conventional Fermat algorithm.

MULTIPLE ANKYLOSIS ON MAXILLARY AND MANDIBULAR PRIMARY MOLARS WITHOUT PERMANENT SUCCESSOR (계승치의 결손을 동반한 상, 하악 유구치의 다발성 유착에 대한 증례보고)

  • Jung, Hwi-Hoon;Choi, Hyung-Jun;Kim, Seong-Oh;Choi, Byung-Jai;Lee, Jae-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.32 no.3
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    • pp.403-408
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    • 2005
  • Ankylosis is defined as a fusion of cementum or dentine with alveolar bone. Due to the loss of the periodontal ligament on the ankylotic area, the tooth is incapable of continued eruption and hence is unable to follow the normal vertical development of the neighboring teeth and alveolar process. A 6-year-old female was referred to the Dept. of Pediatric Dentistry for ankylosis of primary molars and congenital missing of permanent premolars on both jaws. She had neither specific past medical history nor trauma and infection history in oral and maxillofacial region. Radiographic finding is that the maxillary primary molars were the early onset of ankylosis and had fast root resorption rate. However the mandibular primary molars were ankylosed later and being resorbed slower than maxillary primary molars. The object of treating this case is to maintain the proper alveolar bone growth and retention of deciduous molars. The point of managing this case is as follows: Proper treatment (observation, restoration, or extraction) should be established after thorough consideration of the time of onset, the root resorption rate, progression of infraocclusion and the development of alveolar bone support. We should consider the timing of extraction of the ankylosed teeth without problem of neighbouring alveolar bone growth and tilting of adjacent teeth in the view of growth spurt. Early diagnosis is important to avoid many of the complications with infraoccluded primary molars.

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The Concept of 'Wisdom' and Its Perception According to a Survey of Science Teachers ('지혜'의 개념과 과학교사들의 '지혜'에 대한 인식)

  • Lim, Insook;Song, Jinwoong
    • Journal of The Korean Association For Science Education
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    • v.37 no.4
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    • pp.731-745
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    • 2017
  • This study is a part of our research project that considers 'Science as Wisdom (SaW)' as a new approach to science education. We presented a review of previous studies on wisdom from relevant areas as philosophy, psychology and education, and drew a few educational meanings. We also conducted a survey of science teachers' perception of wisdom to obtain implications for a follow-up study. The survey was conducted on pre-service science teachers, in-service science teachers, and teachers of other subjects. The results of this study are as follows: First, all three groups of participants perceive 'practical' domain of wisdom as most important while 'interpersonal' domain was perceived as least important. Second, all three groups of participants perceive that 'to catch what the most important problem is,' is the most important among 20 elements of wisdom. Third, when participants were asked about the 'wise people around them', the interpersonal domain followed as the second most frequent response after the 'practical' domain, which was in contrast to our first finding above. Fourth, about 80% of all participants answered that wisdom can be cultivated through school education. Finally, answers to the question asking the scientific concepts related to wisdom were categorized into four types as follows: (1) the wisdom required to understand and apply scientific knowledge, (2) the wisdom included in the meaning of scientific knowledge, (3) the wisdom needed to discover scientific knowledge, (4) the wisdom that can be developed through scientific activities.

Fast algorithm for incorporating start and goal points into the map represented in a generalized visibility graph (출발점과 목표점을 일반화 가시성그래프로 표현된 맵에 포함하기 위한 빠른 알고리즘)

  • Yu, Kyeon-Ah;Jeon, Hyun-Joo
    • Journal of the Korea Society for Simulation
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    • v.15 no.2
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    • pp.31-39
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    • 2006
  • The visibility graph is a well-known method for efficient path-finding with the minimum search space modelling the game world. The generalized visibility graph is constructed on the expanded obstacle boundaries to eliminate the "wall-hugging" problem which is a major disadvantage of using the visibility graph. The paths generated by the generalized visibility graph are guaranteed to be near optimal and natural-looking. In this paper we propose the method to apply the generalized visibility graph efficiently for game characters who moves among static obstacles between varying start and goal points. Even though the space is minimal once the generalized visibility graph is constructed, the construction itself is time-consuming in checking the intersection between every two links connecting nodes. The idea is that we build the map for static obstacles first and then incorporate start and goal nodes quickly. The incorporation of start and goal nodes is the part that must be executed repeatedly. Therefore we propose to use the rotational plane-sweep algorithm in the computational geometry for incorporating start and goal nodes efficiently. The simulation result shows that the execution time has been improved by 39%-68% according to running times in the game environment with multiple static obstacles.

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A study on the Need for Curriculum Contents in each Sub-area of High School Home Economics Education (고등학교 가정과 교육을 위한 교과과정 영역별 필요도)

  • 이금남;김행자;안영희;이남기
    • Journal of Korean Home Economics Education Association
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    • v.8 no.1
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    • pp.1-10
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    • 1996
  • This study aims at finding a new home economics education which will include male and female students as its teaching objects, and then providing home economics teachers with useful materials. For this purpose I examined analized male and female the upper secondary school students’and parents’recognition and demand to the home economics education The conclusion of this study is summarized as follows: 1. There was significant difference between male students(73.7%) and female students(89.8%) in the necessity for studying Home Economics(P<.001). In the necessity of Home Economics education, male students emphasized the spiritual part but female students emphasized the functional part. In part of parents, there was no significant difference between fathers(95.5%) and mothers(96.4%). 2. The necessity of each part in the contents of Home Economics 1) In the part of family, there was significant difference between male and female students in the true nature of family, the role and responsibility of family, and the laws relating to family(P<.001). There was significant difference between mothers and fathers in the true nature of family and the role and responsibility of family. Fathers and male students emphasized the true nature of family and the role and responsibility of family more than mothers and female students did. 2) In the Home management and economy parts, there was significant difference between male and female students in the significance of home management(P<.001), the relation of family to society(P<.001), and fluctuating measures for home economy. There was significant difference between fathers and mothers in the relation of family to society(P<.05). Fathers and male students emphasized the relation of family to society more than mothers and female students did. Mothers, male and female students emphasized the importance of the protection of consumers. 3) In the clothes part, male students emphasized the role of clothes, the disign and making of clothes(P<.001), the present situation of the resources of clothing and the distribution of clothes (P<.05) more than female students did. 4) In the part of food, there was significant difference between male and female students in the kinds and function of nutritive elements(P<.05). Parents and students emphasized the importance of selecting good food. 5) In the part of housing, male students emphasized home planning, and arrangements and facilities of house more than female students did. Female students emphasized the interior of the house(P<.05). Fathers emphasized the planning of a residential space and arrangements and facilities of a house(P<.05) more than mothers did. 6) In the parts of human development and upbringing, and upbringing, male students emphasized the significance of being parents, family planning and the population problem(P<.001), pregnancy and delivery(P<.01), and the chracteristic of juvenile development(P<.05) more than female students did. Parents and students emphasized the importance of prevention and countermeasures for diseases and the significance of being parents.

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A Comparison of Alcohol Secondhand Effects among Korean and U.S. College Students (한국과 미국 대학생의 간접음주피해 비교)

  • Chun, Sung-Soo;Sohn, Ae-Ree;Reid, Easton A.;Inot, Rubelyn;Kim, Mi-Kyung;Percoheles, Grace;Lee, Sang-Sook;Wechsler, Henry
    • Korean Journal of Health Education and Promotion
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    • v.26 no.5
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    • pp.115-127
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    • 2009
  • Objectives: To compare alcohol secondhand effects among US and Korean students. Methods: Nationally representative 4-year colleges of two countries were involved in this cross-national comparison study. Data from the 2001 U.S. College Alcohol Study and the 2003 Korean College Alcohol Study came from 120 colleges in 38 U.S. states and the District of Columbia and 60 colleges in Korea. Randomly selected 4-year college students from the U.S. (10,924) and Korea (2,385) participated in the study using self-reports of alcohol use and perceptions of drinking as assessed by College Alcohol Study questionnaires. Results: Korean students were tend to more likely to have being a victim of sexual assault or date rape, having to take care of drunken students and finding vomit in the hall or bathroom of residence, than US students, while US students were tend to more likely to have being insulted or humiliated, having a serious argument and quarrel, being pushed, hit, or assaulted, having study/sleep interrupted, and experiencing an unwanted sexual advance than Korean students. Conclusion: In general, US students were more likely to suffer interrelationship problems after drinking while Korean students were more likely to have physical and individual drinking related problems.

Rheological Behavior of Lyotropilc Solutions of Cellulose in the $NH_3/NH_4SCN$ Solvent System

  • Jo, Jae-Jeong;Cuculo, J.A.;Theil, M.H.
    • Proceedings of the Korean Fiber Society Conference
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    • 1990.06b
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    • pp.36-37
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    • 1990
  • In the past, facile dissolution of cellulose has been hampered by the lack of suitable nondegrading solvents. Recently, this problem has been solved in our laboratory by the discovery of an inexpensive, convenient solvent system, that is the mixture of $NH_3\;and\;NH_4SCN$, for cellulose. Also, the $cellulose/NH_3/NH_4SCN$ solution system has been found to form the anisotropic, i.e., liquid crystalline phase. It is believed that both the cholesterio and the nematic phase occur. This finding has prompted extensive on-going researoh on the formation of the liquid crystalline phase from an inexpensive natural source such as cellulose since the nematic phase is envisioned as an excellent precursor sources for products with desirable properties, for example, high modulus and high strength. This interest naturally leads to a desire to understand the theological properties of the nematic phase so that the transformation of the nematic phase to the solid state with desirable properties can be efficiently accomplished, ;From this point of view, the theological behavior of the $cellulose/NH3_/NH_4SCN$ system has been studied as a function of shear rate and shear stress over a wide range of solvent compositions, cellulose concentration, centrifugation and urea contents, Results indicate that the viscosity decreases with increasing shear rate. A marked shear thinning behavior and a quasi-Newtonian behavior were observed in the low shear rate region and in the high shear rate region, respectively for all solvent compositions. The $cellulose/NH_3/NH_4SCN$ solution system only exhibited the viscosity increase with increasing cellulose concentration and failed to show the viscosity drop generally observed at the point of incipience of liquid crystal formation, This may be due to the gel-like nature of the solution by the association of the rodlike molecules into bundles which may serve as crosslinking points giving the cellulose solution a network structure. Also, simply hydrogen bonding may be so restrictive of molecular mobility that a viscosity drop is blocked. In addition to the above results, yield stress and thixotropy were also observed in the $cellulose/NH_3/NB_4SCN$ solution system which are characteristics of liquid crystal and gel, The results of the effect of centrifugation on viscosity show that viscosity decreases by the application of centrifugation. This may be explained by the change of the piled polydomain structure to the dispersed polydomain structure due to the pressure gradient generated during centrifugation.ation.

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An Auto-Verification Method of Security Events Based on Empirical Analysis for Advanced Security Monitoring and Response (보안관제 효율성 제고를 위한 실증적 분석 기반 보안이벤트 자동검증 방법)

  • Kim, Kyu-Il;Park, Hark-Soo;Choi, Ji-Yeon;Ko, Sang-Jun;Song, Jung-Suk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.3
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    • pp.507-522
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    • 2014
  • Domestic CERTs are carrying out monitoring and response against cyber attacks using security devices(e.g., IDS, TMS, etc) based on signatures. Particularly, in case of public and research institutes, about 30 security monitoring and response centers are being operated under National Cyber Security Center(NCSC) of National Intelligence Service(NIS). They are mainly using Threat Management System(TMS) for providing security monitoring and response service. Since TMS raises a large amount of security events and most of them are not related to real cyber attacks, security analyst who carries out the security monitoring and response suffers from analyzing all the TMS events and finding out real cyber attacks from them. Also, since the security monitoring and response tasks depend on security analyst's know-how, there is a fatal problem in that they tend to focus on analyzing specific security events, so that it is unable to analyze and respond unknown cyber attacks. Therefore, we propose automated verification method of security events based on their empirical analysis to improve performance of security monitoring and response.