한산${\cdot}$거제만 굴 양식장의 양식밀도에 관한 연구

조창환,CHO Chang Hwan 한국수산과학회 1980 한국수산과학회지 Vol.13 No.2

한산${\cdot}$거제만 굴 양식장에 관한 $1970\~1979$년까지 사이에 조사된 여러 가지 기존 자료와 1978년에 조사한 몇 가지 저질에 관한 조사자료를 토대로 한 굴양식장의 양식밀도에 관한 연구 결과는 다음과 같다. 1. 각 양성장에 있어 양성중인 굴밀도와 양성장 저이중에 함유되어 있는 COD, 페오파이틴의 양으로부터 구한 저이오염도간에는 상관이 있었다. 저이오염도 12를 한산${\cdot}$거제만의 한계치로 하여 평균 수심에 따른 단위면적당 굴 뭉치 수(C)와 저이오염도 (M)간의 회선직선식은 뗏목식의 경우 M=2.7341+1.8945C, 로우프식의 경우 M=6.4565+1.0988C에 적용하여 추정된 적정 양식밀도는 수하연수로 $m^2$당 뗏목식 0.12연, 로우프식 0.25연이었다. 2. $1970\~1978$년간의 양식결과에서 뗏목당 수하연수가 $350\~558$연 사이에서는 수하연수가 많을 수록 뗏목당 생산량은 많았고, 뗏목 1태가 점유한 수면적이 $1,000\~6,000m^2$까지는 태당 점유면적의 증가에 따라 생산량도 증가하였다. 뗏목당수하연수$(S_R)$와 뗏목당 생산량$(P_R)$ 관계식인 $P_R=-1.1272+0.009823S_R$와 뗏목 점유 면적$(D_R)$과 수하연당 생산량$(A_R)$의 관계식인 $A_R=4.7254+0.000604D_R$에 출하중심시기의 뗏목당 생산량 3.2t을 대입하여 구한 적정 양식밀도는 $m^2$당 약 0.11 연이다. 3. 단위면적당 수하연수(S)와 수하연당 생산량 (P/S)의 관계식인 $\frac{P}{S}=11.7213-44.2472S$에서 단위 면적당 수하연수가 많을수록 수하연당 생산량은 직선적으로 감소하였고, 이 식의 변형인 포물선식인 $P=11.7213\;S-44.2472S^2$에 의하면 수하연당 생산량은 $m^2$당 0.13연 수준에 달하기 까지는 증가하고 이 수준을 넘으면 오히려 감소한다. 이때 기대되는 최대 생산량은 약 5,600t으로 추정된다. 4. 양식밀도와 저이오염도, 뗏목당 수하연수와 뗏목당 점유면적에 따른 생산량 및 수하연 밀도와 연당 생산량의 3가지 측면에서 검토한 결과를 종합하건데, 한산${\cdot}$거제만 굴 양식장에 있어, 적정 양식밀도는 수하연수로 $m^2$당, 뗏목식에서 $0.11\~0.13$연, 로우프식에서 0.25연으로 추정된다. 5. 현재 한산${\cdot}$거제만의 굴 양식밀도는 수하연수로 $m^2$당, 뗏목식에서 0.24연, 로우프식에서 0.28연으로서 적정 양식밀도의 한계치를 초과하고 있다. Farming density of oyster cultured in Hansan-Geoje Bay was studied to obtain the optimal farming density based on the biosedimentation analysis and the annual yield data from 1970 to 1979. Farming density of oyster extrapolated by means of pollution grade of sediment is significantly correlated to COD and phaeophytin content of the bottom mud of the bay. Pollution grade is linearly related to the number of oyster clusters suspended in the unit area. Optimal farming density was $0.12\;string/m^2$ in case of raft culture, and it was $0.12\;string/m^2$ in case of long-line culture. Farming density was well expressed by the number of strings per raft and the area covered by a raft. As strings per raft increased from 350 to 558, total yield from a raft increased and when occupied sea area per raft ranged from $1.000\;m^2\;to\;6,000\;m^2$, the yield per raft linearly increased as the area increased. This analysis suggests that the optimal density be 0.11 string per unit area $(m^2)$. As increasing the number of strings per $m^2$ the yield per string decreases, and this is well dipicted by a linear function. At this time the yield per unit area increases when the number of string increases up to the density of $0.13\;strings/m^2$. From the point of these three comprehensive analyses the optimal density was $0.11\~0.13\;string/m^2$ in case of raft culture and $0.25\;strings/m^2$ in case of long-line culture in Hansan-Geoje Bay. The maximum expected yield of oyster in Hansan-Geoje Bay is approximately 5,600 tons when maintained the string density at $0.11\~0.13\;string/m^2$.

조지훈 초기시의 운율과 구조

조창환 ( Chang Whan Cho ) 한국현대문예비평학회 2008 한국문예비평연구 Vol.0 No.25

人工眞珠 養殖에 關한 試驗硏究

조창환(Chang-Hwan CHO),권우섭(Woo-Seop KWON),김무상(Moo-Sang KIM),김남길(Nam-Gil KIM),임동택(Dong-Taik LIM) 한국수산과학회 양식분과 1988 韓國養殖學會誌 Vol.1 No.1

메탄올 농도에 따른 직접 메탄올 연료전지의 성능 해석

조창환(Changhwan Cho),김용찬(Yongchan Kim),장영수(Young-Soo Chang) 대한설비공학회 2008 설비공학 논문집 Vol.20 No.3

DMFC(Direct Methanol Fuel Cell) is one of promising candidates for power sources of small mobile IT devices like notebook, cell phone, and so on. Efficient operation of fuel cell system is very important for long-sustained power supply because of limited fuel tank size. It is necessary to investigate operation characteristics of fuel cell stack for optimal control of DMFC system. The generated voltage was modeled according to various operating condition; methanol concentration, stack temperature, and load current. It is inevitable for methanol solution at anode to cross over to cathode through MEA (membrane electrode assembly), which reduces the system efficiency and increases fuel consumption. In this study, optimal operation conditions are proposed by analyzing stack performance model, cross-over phenomenon, and system efficiency.

트위터 이용행태 분석

조창환(Chang Hoan Cho),성윤희(Yoon Hee Sung),한경정(Kyung Jung Han),권택주(Taek Joo Kwon),최원영(Won Yong Choi) 한국광고홍보학회 2011 광고연구 Vol.0 No.88

본 연구는 소셜 네트워크 서비스 중 하나인 트위터 이용자의 특성 및 영향력을 살펴보고, 개인 및 기업 트위터의 이용행태를 분석해보고자 하였다. 이를 위해 총 3861개의 트위터를 대상으로 내용분석을 실시하였다. 분석 결과에 따르면, 트위터 이용자의 영향력을 측정하는 지표로서의 팔로워수와 언급수, RT수는 정적인 상관관계가 있는 것으로 나타났다. 또한 팔로잉수, 트위터 사용기간, 하루 평균 트윗수 변인들이 영향력(팔로워수, 언급수, RT수) 모두에 영향을 미치는 요인으로 분석되었다. 성별에 따른 트위터 이용자의 영향력 차이를 분석한 결과, 남성이 여성보다 높은 팔로워수, 언급수, RT수를 보여주고 있었다. 한편, 트위터 이용자들의 관심글 주제를 분석한 결과, 기업/단체의 홍보글을 수집한 이용자는 관심글 이용자 중 9%로 나타나, 광고/홍보 매체로서의 트위터의 가능성을 보여주었다. This study is designed to examine the characteristics of Twitter users, their influence on other users, and how both individuals and corporations use Twitter. For this, 3861 Twitter accounts were content-analyzed. This study found positive correlations among three measures of twitter influence(the number of followers, mentions, and retweets). It was also found that three variables(the total number of followers, length of Twitter usage, and the average number of tweets per day) have a significant effect on the extent of influence for Twitter users(the number of followers, mentions, and retweets). The analysis of gender difference in twitter influence showed that males had more followers, mentions, and retweets than females. In addition, the analysis of the subjects of favorites that each Twitter user had saved demonstrated that nine percent of Twitter users saved the tweets that were tweeted by corporations and communities to their tweet favorite list. This implies that Twitter has a potential as an advertising and PR medium.

한국현대시의 프란츠 카프카 수용

조창환(Cho Chang-whan) 한국시학회 2011 한국시학연구 Vol.- No.31

The purpose of this study is verifying the reception of Franz Kafka, one of the most outstanding writer of existentialism in 20th century, in Modern Korean literature. It is deeply influenced by the works of the writer which concerned about alienation and anxiety of the existence of human being, absurdity of the fate of man, dialect of desperation and hope, problem of solitude and horror. Literary style of Kafka which has the characteristics of fable description and fantastic stories has been greatly stimulated to the techniques in creative writing into modern Korean literary works. There are some Korean poets who wrote their poems motivated from Kafka’s works. Lee, Chul-bum and Kim, Kwang-kyu described the desperation in front of sanctity or absolute power, Kim, Seung-hee and Kim, Jin-Kyung expressed the horror, anxiety and pent-up feelings in their poems which motivated from the “Castle”, “Metamorphosis” and “The Judgement” by Kafka. On the other hand, Lee, Kun-chung and Cho, Chang-whan dealt with the solidarity and self-conflict which is the characteristic theme of Kafka by parodying “Fasting clown” in their works. Also, we can find some poems that recited the name of Kafka or the image of him. O Kyu-won satirized self-ridiculously criticizes the appearance of modern life in extreme commercialism and fetishism in his poem. Jang, Suk-ju tried to find hope in desperation by describing that the desperation comes like ‘K in Kafka’ in his poem. Park, Ju-taek figured grotesque fantasy which influenced by works of Kafka. We can discover the influence of Kafka into Korean literature not only by the examples that recited or parodied from his work but also the way of recognition of the world and human being. It is obvious that his work has been deeply influenced to Korean modern literature by stimulating them and widening amplitude of imagination.

원전기기제어시스템의 위험도 감소 방안

조창환(Chang-Hwan Cho),김중선(Jung-Seon Kim),김양모(Yang-Mo Kim) 대한전기학회 2007 대한전기학회 학술대회 논문집 Vol.2007 No.10

디지털기술의 발전으로 원자력발전소의 기기제어시스템은 Single-loop Control과 하드와이어드된 배선을 이용한 제어방식에서 Multi-loop Control과 통신망을 이용한 제어방식으로 변화되고 있다. 이에 따라 기기제어시스템의 단일고장발생시 플랜트 위험도가 증가하게 됨으로 플랜트 위험도 감소를 위한 연구가 필요하다. 위험도 감소를 위한 방안에는 기기제어시스템을 구성하는 기기의 신뢰도를 향상시키는 방법과 제어루프에 작동기기를 적절하게 배치하여 단일고장발생시 플랜트 위험도를 감소시키는 방법이 있다. 본 논문에서는 플랜트 위험도 감소 방안 중 작동기기 할당 방안에 대해 기술하였다.

한국 현대시사 연구의 문제점과 전망

조창환(Cho Chang-Whan) 한국시학회 2007 한국시학연구 Vol.- No.19

Early studies of the history of modern Korean poetry mainly adopted bibliographical critical methodolgy, as in The History of Modern Korean Literature by Cho, Yeon-hyun and The History of Modern Korean Poetry, by Chung, Han-mo, which took initiative of the studies. Later, many parts of the former were corrected and amended by scholars who ranged more extensive literary materials, while the latter criticized that the former neglected the background of poetry, literary activities and the evaluation of poetic works. The most outstanding studies of history of modern Korean poetry, The History of Modern Korean Poetry and The History of Contemporary Korean Poetry by Kim, Yong-jik, made use of literary historicism. The author concerned the social background of poetry, evaluated literary activities and their social effects and roles, and arranged major poets and their literary works in his literary history. But he confused history of literature and history of thoughts since he overemphasized on the social background of literary works and writers' thoughts. The major points of arguments in description of history of poetry in modern Korean literature are theory of cultural transplantation, theory of cultural traditionalism, the starting point of modern poetry, and the conception of modernity in Korean poetry. The modern Korean poetry seems to have two sharply contrasting perspectives from its beginning, which are manifested in the interpretation of modern Korean history of poetry. But they are only the matter of standing point of the scholars and can be compromised by more comprehensive viewpoint. The most reasonable starting-point of modern poetry is the Enlightenment Period, and the most appropriate conception of modernism in Korean poetry is the literary movement of Imagism and Surrealism in 1930s, though their modernity was distorted and transformed and different from that of the European and American literature.

이성분 나노에멀전의 입도 및 열전도도 측정

조창환(Changhwan Cho),설혜연(Hea Youn Sul),정정열(Jung-Yeul Jung),강용태(Yong Tae Kang) 대한설비공학회 2009 대한설비공학회 학술발표대회논문집 Vol.2009 No.-

Binary nanoemulsions which are defined as the, oil-droplet suspensions in binary solution (H₂O/LiBr), are developed to enhance the heat and mass transfer performance of absorption refrigeration systems. In this study, a novel two-step method is proposed to prepare the stable oil-in-binary solution (O/S) emulsion. Polymer is used as a steric stabilizer to stabilize the oil-droplets in a strong electrolyte (H₂O/LiBr). It is found that the thermal conductivity of the binary nanoemulsion is inversely proportional to the emulsion size while the concentrations of oil and H₂O/LiBr are less dominant for the thermal conductivity of binary nanoemulsions.

현대시 운율 연구의 방법과 방향

조창환(Cho Chang-Whan) 한국시학회 2008 한국시학연구 Vol.- No.22

The new-style poetry written by Choi, Nam-sun(최남선) in the Enlightenment Period was influenced by metrical system of Japanese poetry. The main metrical device of his poems is 7ㆍ5 syllable rhythm which imitated Japanese one. The style soon prevailed and was popularized in Korean poetry, since its substructure, trimetre, originating from traditional Korean folklore, met public favor in the period. Kim, So-wol(김소월), the outstanding poet in 1920's, made the most of it. Many of his excellent poems described typical Korean lyricism and sentiment, and his poems had artistic quality resulting from this metrical scheme, which variated and modernized 7.5 syllable rhythm. The methodology of metrical analysis in that period was pure-syllabic metre theory and Cho, Yoon-je(조윤제) explained the metrical scheme of Sijo(시조) by means of it, which generalized the prosody of its fixed form. Later, the theory was criticized in that it is not appropriate to analyze Korean verse, since the metric units are not fixed in terms of the syllabic number and hard to count. Instead, the concept of foot was adopted in the methodology, where trimetre and tetrametre are dominant. However, I claim that the theory is not sufficient either to explain Korean verse because it has complicated metrical devices such as 7ㆍ5 syllable rhythm, which could be divided by uneven three or four metrical units. I suggest adopting a new concept, 'Yoolmadi'(율마디, metrical joint), which can comprise this unique metrical scheme. The terminology is similar to 'colon', closely connected group of words, proposed by J. Lotz. Kim, Young-rang(김영랑), Seo, Jung-ju(서정주), and Park, Mok-wol(박목월) developed aesthetic sense of poetry by means of their characteristic metrical variations and exceptions. The rhythmical sense of trimetre is mixed with the stability of tetrametre in the poem "Until peonies bloom"(모란이 피기까지는) by Kim, Young-rang. This double structure of metrical scheme was realized in natural reading intonation of the poem 'The secret word"(밀어) by Seo, Jung-ju. In addition, symmetrical arrangement of lines and counterbalanced metrical form make unique beauty in formalism in the poem "Mountain peach blossoms(산도화)" by Park, Mok-wol. In their free verse, the regularity of metre is abandoned. Instead, cadences approximating the flow of speech are employed.