• 제목/요약/키워드: Imaginary Number

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CW 도플러 레이더와 FFT를 이용한 물체의 접근 이탈 정보 판단 알고리즘 (Detection Algorithm for Information on Approach or Deviation of Objects Using CW Doppler Radar and FFT)

  • 신현준;한병훈;오창헌
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2015년도 추계학술대회
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    • pp.999-1001
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    • 2015
  • CW 도플러 레이더는 도플러 효과를 이용하여 특정한 물체의 상대 속도를 획득할 수 있다. 하지만 두 개 이상의 물체를 탐지하기 위해서는 CW 도플러 레이더에 FFT를 사용하여 주파수 영역에서 분석해야하며, 이러한 경우 주파수 영역에서는 물체의 개수와 속도를 구할 수 있지만 물체의 접근 또는 이탈 정보를 판단하기에는 어렵다는 단점이 존재한다. 본 논문에서는 두 개 이상의 물체를 탐지하기 위해 FFT를 사용할 경우 주파수 영역에서 물체의 접근 또는 이탈 정보를 효율적으로 판단하기 위한 알고리즘을 제안한다. 제안하는 알고리즘은 주파수 영역에서 실수부와 허수부로 나눈 후 각 주파수들의 진폭을 합한 값이 주파수의 좌측에 있으면 이탈, 우측에 있으면 접근으로 판단한다.

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배전계통조류계산을 위한 새로운 알고리즘에 관한 연구 (A Study on Development of a New Algorithm to Solve Load Flow for Distribution Systems)

  • 문영현;유성영;최병곤;하복남;이중호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.918-922
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    • 1998
  • With the development of industry, the qualitical advancement of power is needed. Since it is placed in the end step of power system, the fault at the distribution system causes some users blackout directly. So if the fault occurs, quick restoration is very important subject and, for the reason, induction of the distribution automation system is now being progressed briskly. For the quick restoration of the faulted distribution system, the load shedding of the blackout-area must be followed, and the other problems like the shedded load, faulted voltage and the rest may cause other accident. Accordingly load shedding must be based on the precise calculation technique during the distribution system load flow(dist flow) calculation. In these days because of its superior convergence characteristic the Newton-Raphson method is most widely used. The number of buses in the distribution system amounts to thousands, and if the fault occurs at the distribution system, the speed for the dist flow calculation is to be improved to apply to the On-Line system. However, Newton-Raphson method takes much time relatively because it must calculate the Jacobian matrix and inverse matrix at every iteration, and in the case of huge load, the equation is hard to converge. In this thesis. matrix equation is used to make algebraical expression and then to solve load flow equation and to modify above defects. Then the complex matrix is divided into real part and imaginary part to keep sparcity. As a result time needed for calculation diminished. Application of mentioned algorithm to 302 bus, 700 bus, 1004 bus system led to almost identical result got by Newton-Raphson method and showed constant convergence characteristic. The effect of time reduction showed 88.2%, 86.4%, 85.1% at each case of 302 bus, 700 bus system 86.4%, and 1004 bus system.

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장 폴 고티에 무용의상의 조형성에 관한 연구 (A Study on the Aesthetic Characteristics of the Dance Costume of Jean Paul Gaultier)

  • 한경하;금기숙
    • 복식
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    • 제60권9호
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    • pp.1-15
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    • 2010
  • Fashion designer Jean Paul Gaultier incorporated his own boundless and unique artistic Into his design of dance costumes, presenting an unobstructed imaginary world that was filled with freedom, which is no less than one would expect from the one-time enfant t${\'{e}}$rrible of Paris fashion. This creativity of Gaultier was made possible only through the fantastic partnership he formed with the French modern dancer, R${\'{e}}$gine Chopinot. Gaultier and Chopinot shared a deep-rooted sympathy that enabled their own artistic worlds to fully mingle and cross over, resulting in a doubled synergy of their talent and their fame. This study analyzed 11 dancing costumes created through the collaborated efforts of those two enfants t${\'{e}}$rribles, one from the fashion industry and the other from the world of dance. The following are the results of my analysis. Gaultier's dance costumes served as a artistic venue for experimenting with a number of creative inspirations lurking in his mind, which were sometimes expressed in pr${\^{e}}$t-${\`{a}}$-porter collections. Instead of the decorative and expressive features of conventional dance costumes, his was the revival of the dancer's persona as a human being, ablaze with individuality and uniqueness. He pointed out that there is no good in the distorted turturro's fixed point of view, and the great joy of an opposing way of thinking that overturned the established. Leotard material was used as a second skin by transforming it into various styles and delivering his message. In addition, obscene and sexual expressions were delivered in a direct narrative. His eccentric ideas provided entertainment while showing his oppositional way of thinking. In the dance, the effect of the costumes was doubled by the use of cumbersome and exaggerated accessories, which is generally forbidden in modern dance.

다중 분산 웹 클러스터모델의 안전한 데이터 전송을 위한 상호 인증 프로토콜 (Mutual Authentication Protocol for Safe Data Transmission of Multi-distributed Web Cluster Model)

  • 이기준;김창원;정채영
    • 정보처리학회논문지C
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    • 제8C권6호
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    • pp.731-740
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    • 2001
  • 기존의 클러스터 시스템을 확장한 다중 분산 웹 클러스터 모델은 개방 네트워크상에 존재하는 다수의 시스템 노드들을 단일한 가상 네트워크로 구축하여 사용자로부터 요구되어지는 대규모 작업을 병렬 컴퓨팅 방식으로 처리하는 클러스터 시스템이다 구성된 특성상 다중 분산 웹 클러스터 모델은 불법적인 3자에 의해 내부 시스템 노드들이 노출되어 있으며, 각 시스템 노드간의 협조작업 시 고의적인 방해와 공격으로 정상적인 작업수행이 불가능할 가능성을 지니고 있다. 본 논문에서는 시스템 노드의 서비스 코드 블록의 등록, 요구, 협조 및 결과취합 시 해당 시스템노드의 인증을 위하여 키 분배방식을 통한 시스템 노드 상호 인증 프로토콜을 제시하며, 전체 시스템 노드의 대칭키를 안전하고 효율적으로 관리하며 분배하는 SNKDC를 설계한다. SNKDC는 시스템 노드가 작업수행 시 필요한 대칭키를 분배하며, 제공된 키를 기반으로 시스템 노드는 암호화된 패킷을 전송한다. 시스템 노드간의 주고받는 암호화 패킷은 3자에 의해 해독되거나 거짓 메시지를 통한 정보의 유출을 방지할 수 있다.

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Research on Digital Complex-Correlator of Synthetic Aperture Radiometer: theory and simulation result

  • Jingye, Yan;Ji, Wu;Yunhua, Zhang;Jiang, Changhong;Tao, Wang;Jianhua, Ren;Jingshan, Jiang
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.587-592
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    • 2002
  • A new digital correlator fur an airborne synthetic aperture radiometer was designed in order to replace the conventional analog correlator unit which will become very complicated while the number of channels is increasing. The digital correlator uses digital IQ demodulator instead of the intermediate frequency (IF) phase shifter to make the correlation processing performed digitally at base band instead of analogly at IF. This technique has been applied to the digital receiver in softradio. The down-converted IF signals from each pair of receiver channels become low rate base-band digital signals after under-sampled, Digitally Down-Converted (DDC), decimated and filtered by FIR filters. The digital signals are further processed by two digital multipliers (complex correlation), the products are integrated by the integrators and finally the outputs from the integrators compose of the real part and the imaginary part of a sample of the visibility function. This design is tested by comparing the results from digital correlators and that from analog correlators. They are agreed with each other very well. Due to the fact that the digital correlators are realized with the help of Analog-Digital Converter (ADC) chips and the FPGA technology, the realized volume, mass, power consumption and complexity turned out to be greatly reduced compared with that of the analog correlators. Simulations show that the resolution of ADC has an influence on the synthesized antenna patterns, but this can be neglected if more than 2bit is used.

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GIS를 이용한 2차원 수치모형의 자연하천 적용 (Application of 2D Numerical Model for Natural Rivers using GIS)

  • 김병현;한건연
    • 한국지리정보학회지
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    • 제12권3호
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    • pp.128-142
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    • 2009
  • 현재까지 개발되고 있는 대부분의 유한체적모형은 가상하도 및 실험하도와 같은 단순하도에 적용하여 흐름율과 생성항의 균형문제를 해결하기 위한 여러 가지 노력들이 있어 왔다. 하지만, 실제 자연하천에서의 적용에서는 단순하도에서의 적용에서 나타나지 않았던 여러 가지 문제점들이 발생하며, 이러한 문제점들을 수치적으로 해결하여야 비로소 자연하천에서의 적용이 가능하다. 본 연구에서는 자연하천에 적용가능한 2차원 유한체적모형을 개발하여 2차원 부분적 댐 붕괴에 적용하여 개발모형의 정확성을 검증하고, 한강의 측량단면을 GIS를 이용하여 2차원 격자에 정확하게 반영할 수 있는 간단하고 효율적인 2차원 격자생성기법을 제안하였다. 그리고 제안된 기법으로 생성된 2차원 격자로 한강에 대한 흐름모의를 수행하고 계산수위와 실측수위를 비교하여 자연하천에 대한 개발모형의 정확성 및 적용성을 입증하였다.

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승령(GB18) 혈위와 취혈 방법에 대한 고찰 (Review on the Point Location and Locating Method of GB18)

  • 구성태
    • Korean Journal of Acupuncture
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    • 제35권4호
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    • pp.203-209
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    • 2018
  • Objectives : The GB18 belongs to one of the 92 controversial points in the development of WHO standard of acupuncture point location. The number of Chon measurement of GB18 is described differently in the A-B Classic of Acupuncture and Moxibustion (ChimGuGakEulKyung; AB Classic) and the Complete Compendium of Acupuncture and Moxibustion(ChimGuDaeSeong; Complete Compendium). The aim of the study is to review the point location of GB18 and compare the relation of the location of BL7. In addition, I would like to propose new locating method of GB18. Methods : In order to review I examined the expressions of the location of GB18 and the mapping location on the acupuncture chart in the landmark classic acupuncture literatures. Results : In the most literatures, the location of GB18 was described by the distance from the GB17. The distance was 1.5 chon with one exception of 1 chon. The intervals from GB15 to GB18 was 1 chon or 1.5 chon. Although the distance from the anterior hairline is the same as 4 chon, mapping points of GB18 and BL7 on the acupuncture chart were different. Conclusions : Consequently, in the AB Classic, meaning of the location is the actual distance of scalp surface. In the Complete Compendium, however, meaning of the location is the hypothetical distance in the imaginary scalp surface. Therefore, it is safe to find the GB18 on the same level with GV20 on the connecting line of bilateral auricular apexes. The relation of GB18 and BL7 should be reconsidered.

한국의 빨간 오징어 유자망 어업과 북서태평양의 해황 변동 (Korean Drift Gillnet Fishery For Flying Squid , Ommastrephes bartrami ( Lesueur ) , and the Variation of Oceanographic Conditions in the North Western Pacific Ocean)

  • 임기봉
    • 수산해양기술연구
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    • 제22권3호
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    • pp.8-16
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    • 1986
  • The fishing conditions of flying squid, ommastrePhes barsram(Lesueur), in the North Pacific Ocean was studied based on the horizontal water temperature data, satellite data from NOAA and statistical data of flying squid fisheries which were collected from 1980 to 1984. The obtained results were as follows; 1. Since 1979, the Korean drift giIlnet fishery for flying squid was launched in North Pacific. Number of operating vessel and catch of flying squid increased gradually every year. The number of vessels were 111 and their annual catches were 42, 977 M/T in 1984. Therefore, Korean drift giIlnet fishery for this species has played an important role in the products of Korean high-sea fisheries. 2. In the beginning of the fisheries, fishing grounds was formed in the west of long. 1800E. In 1982, in consequence of the center which extended eastward, the fishing ground was formed long. 166$^{\circ}$W in the central North Pacific Ocean. Since 1983, the fishing grounds were formed as far as long. 161$^{\circ}$W. The range of general fishing season in the central North Pacific was from June to August. After september, fishing ground was shifted to the west, in the Northwestern Pacific. 3. The Predominant fishing season for the flying squid was August through January of the coming year. Optimum water temperature for flying sguid at surface layer in the Pacific Ocean ranged from 11 $^{\circ}$e to 17$^{\circ}$e in winter, 13$^{\circ}$e to 17$^{\circ}$e in spring, 12. 8$^{\circ}$C to 19.7$^{\circ}$e in summer and 1O.6$^{\circ}$e -18.7$^{\circ}$e in fall. 4. In summer, the Oceanographic condition in the North Pacific Ocean showed that the water temperature at surface layer was lower in 1980, 1983 and higher in 1981, 1982 and 1984 as compared with mean annual water temperature. 5. The characteristics df oceanographic conditions in the fluation, disformation, mixing and other factors of the Kuroshio and Oyashio currents, which have considerably influenced upon the water masses of the areas. 6. The data and information on surface thermal Structure interpreted from Infrared Satellite Imaginary from NOAA-7 and NOAA-8 are very available in estimating water temperature on the areas and investigating the major fishing grounds. 7. According to the fisheries statics of Japanese drift gilInet, the annual catches of flying squid considerably decreased from 225, 942 M/T in 1983 to 133, 217 M/T in 1984. 8. The fishing grounds in the central North Pacific in several fishing seasons were formed as follows: In June, the initial fishing season, the fishing grounds were formed in the vicinity of lat. 35 - 40oN, the central North Pacific east of 179$^{\circ}$E. In July, the fishing ground were formed in the wide arEa of the central North Pacific north of 400N and long. 174$^{\circ}$E-145$^{\circ}$W In Auguest, concentrative fishing operation carried out in :he central North Pacific north of 43$^{\circ}$N and East of 165$^{\circ}$W. On the other hand, in September, main fishing grounds were disappeared and moved to the west.

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현대회화에서의 형태와 물질 -Digital Transfiguration에 관한 연구- (Digital painting: Image transfonnation, simulation, heterologie and transfonnation)

  • 정숙영
    • 조형예술학연구
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    • 제10권
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    • pp.161-181
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    • 2006
  • The words which appeared in my theoretical study and work are image transformation to digital painting, simulation, heterologie and transfiguration, etc. Firstly, let's look into 'digital era' or 'new media era'. Nowadays, the image world including painting within the rapid social and cultural change, which is called as digital era, is having the dramatic change. Together with the development of scientific technology, large number of events which was deemed to be impossible is happening as real in image world Moreover, these changes in image world is greatly influencing to our life. The word which compresses this change of image world and shows is 'digital'. Digit, which means fingers in Latin, indicates separately changing signal, and to be more narrow, it indicates the continual signal of '0' and ' 1' in computer. The opposite word is 'analogue'. As analogue is the word meaning 'infer' or 'similarity', it indicates the signal or form which continuously changes along the series of time when it is compared to digital. Instead of analogue, digital is embossed as a major ruler along the whole area of our current culture. In whole culture and art area, and in whole generalscience, digital is appearing as it has the modernism and importance. The prefix, 'digital', e.g. digital media, digital culture, digital design, digital philosophy, etc, is treated as the synonym of modernism and something new. This advent of digital results the innovative change to the image world, creates the new beauty experience which we could not experience before, and forecasts the formation of advanced art and expansion of creative area. Various intellectual activities using computer is developing the whole world with making the infrastructure. Computer in painting work immediately accomplishes the idea of painters, takes part in simulation work, contingency such as abrupt reversal, extraction, twisting, shaking, obscureness, overlapping, etc, and timing to stimulate the creativity of painters, and provides digital formative language which enables new visual experience to the audience. When the change of digital era, the image appeared in my work is shown in 'transfiguration' like drawing. The word, 'transfiguration' does not indicate the completed and fixed real substance but indicate endlessly moving and floating shape. Thus, this concept is opposite to the substantial consideration, so that various concepts which is able to replace this in accordance with the similar cases are also exist such as change, deterioration, mutation, deformity of appearance and morphing which is frequently used in computer as a technical word. These concepts are not clearly classified, and variably and complicatedly related. Transfiguration basically means the denial of "objectivity' and '(continual) stagnation' or deviation from those. This phenomenon is appeared through the all art schools of art ever since the realism is denied in the 19th century. It is called as 'deformation' in case of expressionism, futurism, cubism, etc, in the beginning of the century, which its former indication is mostly preserved within the process of structural deviation and which has the realistic limit which should be preserved. On the contrary, dramatic transfiguration which has been showing in the modern era through surrealism is different in the point that dramatic transfiguration tends to show the deterioration and deviation rather than the preservation of indicated object. From this point, transfiguration coming out from morphing using computer deteriorates and hides the reality and furthermore, it replaces the 'reality'. Moreover, transfiguration is closely approached to the world of fake or 'imaginary' simulation world of Baudrillard. According to Baudrillard, the image hides and deteriorates the reality, and furthermore, expresses 'not existing' to 'imaginary' under the name of transfiguration. Certain reality, that is, image which is absent from the reality is created and overflowed, so that it finally replaces the reality. This is simulation as it is said by Baudrillard. In turn, Georges Bataille discusses about the image which is produced by digital technology in terms of heterologie. Image of heterologie is the visual signal which is established with the media. Image of media is to have the continuous characteristics of produce, extinction, and transformation, and its clear boundary between images becomes meaningless. The meaning of composition, excess, violation, etc of digital image is explained to heterological study or heteologie suggested as important meaning of Georges Bataille who is a heretic philosopher. As the form and image of mutation shows the shape in accordance with mechanical production, heterologie is introduced as very low materialism (or bas materialisme), in this theory. Heterologie as low materialism which is gradually changing is developing as a different concept and analysis because of the change of time in the late 20s century beside high or low meaning. Including my image, all images non-standardizes and transforms the code. However, reappearance and non-standardization of this code does not seem to be simple. The problem of transformation caused by transfiguration which appears in my digital drawing painting, simulation, heterologie, etc, are the continual problems. Moreover, the subject such as existence of human being, distance from the real life, politics and social problems are being extended to actual research and various expressing work. Especially, individual image world is established by digital painting transfiguration technique, and its change and review start to have the durability. The consciousness of observers who look at the image is changing the subject. Together with theoretical research, researchers are to establish the first step to approach to various image change of digital era painting through transfiguration technique using our realistic and historical image.

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청소년의 사이버 자기개념,자기효능감, 친구관계, 주관적안녕감과 학업성취도: 인터넷 중독인식집단과 비중독집단의 비교 (Analysis of the self-concept in the cyberspace, self-efficacy, relationship with friends, subjective well-being and academic grade: Comparison of adolescents who are addicted to Internet to non-addicted adolescents)

  • 김의철;박영신;탁수연;김정희;오미선
    • 한국심리학회지 : 문화 및 사회문제
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    • 제19권2호
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    • pp.285-318
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    • 2013
  • 이 연구에서는 청소년 인터넷 중독인식집단의 사이버 자기개념과 인간관계, 심리 행동특성을 이해하는데 주된 관심이 있다. 이를 위해 인터넷 중독인식집단과 비중독집단의 사이버 자기개념, 자기효능감, 친구관계, 주관적안녕감 및 학업성취도의 차이를 비교하였다. 최종 분석대상 수는 1,057명(남 545명, 여 512명)이었으며, 학교별로는 중학생 326명, 일반계 고등학생 361명, 특성화 고등학생 370명이었다. 분석결과, 첫째, 사이버공간에 있을 때 자기인식에 대해 질적 분석을 한 결과, 인터넷 중독인식집단은 재미있다가 가장 높은 반응률을 나타내고 그 다음으로 평소와 같다, 시간을 보낸다, 가상인물이 된다 등의 순서를 보였다. 반면에 인터넷 비중독집단은 평소와 같다가 가장 높은 반응률을 나타내고, 그 다음으로 재미있다, 시간을 보낸다, 가상인물이 된다 등의 순서를 나타내었다. 인터넷에서 게임할 때 자기인식으로는 인터넷 중독인식집단과 비중독집단 모두 재미있다를 가장 많이 지적하였는데, 응답자의 반수가 이에 해당하였다. 그 다음으로 몰입한다, 거칠어진다와 같은 범주들이 포함되었다. 둘째, 인터넷 중독인식집단과 비중독집단의 자기효능감 차이를 공변량분석한 결과, 비중독집단이 중독인식집단보다 자기조절학습효능감, 관계효능감, 어려움극복효능감이 더 높았다. 셋째, 인터넷 중독인식집단과 비중독집단의 친구관계 차이를 공변량분석한 결과, 친한 친구 수와 가까운 친구 수에서 모두 의미있는 차이가 없었다. 그러나 비중독집단은 중독인식집단보다 친구로부터 정서적 지원을 더 많이 받았고, 반면에 따돌림을 적게 경험하였다. 넷째, 인터넷 중독인식집단과 비중독집단의 주관적안녕감 차이를 공변량분석한 결과, 비중독집단이 중독인식집단보다 훨씬 주관적안녕감이 높은 것으로 확인되었다. 다섯째, 인터넷 중독인식집단과 비중독집단의 학업성취도 차이를 공변량분석한 결과, 비중독집단이 중독인식집단보다 객관적 성적만이 아니라 주관적 성취지각에서도 높은 학업성취도를 나타내었다.

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