• 제목/요약/키워드: observation ability

검색결과 409건 처리시간 0.023초

데이터 웨어하우징의 구현성공과 시스템성공 결정요인 (Factors Affecting the Implementation Success of Data Warehousing Systems)

  • 김병곤;박순창;김종옥
    • 한국정보기술응용학회:학술대회논문집
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    • 한국정보기술응용학회 2007년도 춘계학술대회
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    • pp.234-245
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    • 2007
  • The empirical studies on the implementation of data warehousing systems (DWS) are lacking while there exist a number of studies on the implementation of IS. This study intends to examine the factors affecting the implementation success of DWS. The study adopts the empirical analysis of the sample of 112 responses from DWS practitioners. The study results suggest several implications for researchers and practitioners. First, when the support from top management becomes great, the implementation success of DWS in organizational aspects is more likely. When the support from top management exists, users are more likely to be encouraged to use DWS, and organizational resistance to use DWS is well coped with increasing the possibility of implementation success of DWS. The support of resource increases the implementation success of DWS in project aspects while it is not significantly related to the implementation success of DWS in organizational aspects. The support of funds, human resources, and other efforts enhances the possibility of successful implementation of project; the project does not exceed the time and resource budgets and meet the functional requirements. The effect of resource support, however, is not significantly related to the organizational success. The user involvement in systems implementation affects the implementation success of DWS in organizational and project aspects. The success of DWS implementation is significantly related to the users' commitment to the project and the proactive involvement in the implementation tasks. users' task. The observation of the behaviors of competitors which possibly increases data quality does not affect the implementation success of DWS. This indicates that the quality of data such as data consistency and accuracy is not ensured through the understanding of the behaviors of competitors, and this does not affect the data integration and the successful implementation of DWS projects. The prototyping for the DWS implementation positively affects the implementation success of DWS. This indicates that the extent of understanding requirements and the communication among project members increases the implementation success of DWS. Developing the prototypes for DWS ensures the acquirement of accurate or integrated data, the flexible processing of data, and the adaptation into new organizational conditions. The extent of consulting activities in DWS projects increases the implementation success of DWS in project aspects. The continuous support for consulting activities and technology transfer enhances the adherence to the project schedule preventing the exceeding use of project budget and ensuring the implementation of intended system functions; this ultimately leads to the successful implementation of DWS projects. The research hypothesis that the capability of project teams affects the implementation success of DWS is rejected. The technical ability of team members and human relationship skills themselves do not affect the successful implementation of DWS projects. The quality of the system which provided data to DWS affects the implementation success of DWS in technical aspects. The standardization of data definition and the commitment to the technical standard increase the possibility of overcoming the technical problems of DWS. Further, the development technology of DWS affects the implementation success of DWS. The hardware, software, implementation methodology, and implementation tools contribute to effective integration and classification of data in various forms. In addition, the implementation success of DWS in organizational and project aspects increases the data quality and system quality of DWS while the implementation success of DWS in technical aspects does not affect the data quality and system quality of DWS. The data and systems quality increases the effective processing of individual tasks, and reduces the decision making times and efforts enhancing the perceived benefits of DWS.

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들깨의 볶음처리와 산가수분해에 의한 세포모델계 Quinone Reductase 활성유도능의 변화 (Modulation of Cellulalr Quinone Reductase Inducibility by Roasting Treatment and Acid Hydrolysis of Perilla)

  • 홍은영;강희정;권정숙;남영중;서명자;김정상
    • 한국식품영양과학회지
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    • 제26권2호
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    • pp.186-192
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    • 1997
  • 발암물질의 해독에 관여하는 2상 효소계의 지표효소인 QR을 활성화시키는 암예방성분의 존재여부를 탐색한 이전의 연구에서 들깨박의 메탄올 추출물이 hepa1c1c7 cell에서 높은 QR 유도활성을 나타내었다. 본 연구에서는 탈지공정에 앞서 실시되는 볶음과정에서 비활성상태로 존재하던 QR inducer가 활성상태로 유리되는 것으로 가정하고 산가수분해와 볶음처리를 한 후, 각각의 메탄올 추출물에 대한 QR 유도활성을 측정하였다. $100^{\circ}C$에서 30, 60, 120분간 산가수분해시킨 날들깨박의 메탄올 추출액은 가수분해시간이 증가할수록 세포의 QR 활성유도능이 증가하는것으로 나타났다. $180^{\circ}C$$200^{\circ}C$에서 5, 10, 20분간 볶은 들깨박의 경우, QR유도 활성은 날들깨박에 비해 높았으며, 묶음시간이 걸어질수록 증가하는 경향을 보였다. 볶은 들깨박의 메탄올 추출액은 농도가 증가함에 따라 비례적으로 QR 효소 활성을 증가시켰다. 탈지들깨박이 동물조직의 QR 효소활성에 미치는 영향을 생쥐를 이용하여 확인한 결과, 볶은 들깨박의 메탄올 추출물은 QR 효소활성을 간과 위에서 유의적으로 증가시켰고, 날들깨박은 간과 폐에서 유의적으로 효소활성을 증가시켰다. 이렇듯 들깨박은 동물의 여러기관에서 암예방의 지표효소인 QR을 유도하는 것으로 나타나, 발암 물질로부터 생체를 보호하는 물질을 함유하고 있을 가능성이 높은 것으로 추정된다.

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서열환경하에서 안전모 착용시의 인체생리학적 반응 (Thermophysiological Responses of Wearing Safety Hat for Working at a Hot Environment)

  • 박소진;김희은
    • 한국의류학회지
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    • 제26권1호
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    • pp.74-82
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    • 2002
  • 본 연구에서는 서열환경하에서의 안전모 착용과 관련된 생리학적 온열반응을 조사하고 아울러 일반적인 안전모에 통풍을 목적으로 구멍을 뚫어 놓은 안전모가 작업시 체열방산, 체온의 항상성과 같은 생리반응에 어떠한 영향을 미치는지에 대한 검토를 실시하고자 성인 남자 5명을 대상으로 착용실험을 실시하였다. 구멍이 없는 일반적인 형태의 무공 작업 안전모와 통기를 목적으로 구멍을 뚫어 놓은 유공 작업 안전모를 대조군으로 하여, 온도 30$\pm$1$^{\circ}C$, 습도 55$\pm$10%R.H의 인공기후실에서 휴식과 운동을 되풀이하는 총70분간의 실험을 실시하였다. 그 결과를 요약하면 다음과 같다. 1. 직장온과 심박수는 유공안전모 착용시가 무공안전모 착용시 보다 유의하게 낮게 나타났으며, 체열평형과 관련하여 신체기능의 항상성을 유지하는 데에 유공안전모를 착용하는 것이 더 효율적임을 알 수 있었다. 2.각 부위의 피부온과 평균 피부온은 유공안전모 착용시가 무공안전모 착용시보다 유의하게 낮았는데 특히 발한이 다른 부위보다 먼저 시작되는 이마에서 더욱 두드러지게 나타났다. 이는 안전모 착용으로 체온이 상승되어 피부온과 평균 피부온의 상승으로 이어지는 과정에서 유공안전모 착용시 가 무공안전모 착용시보다는 더 유리하다는 것을 알수 있었다. 3. 혈압은 전 구간에 걸쳐 유공안전모 착용시가 무공 안전모 착용시 보다 낮게 나타났다. 유공안전모 착용시가 무공안전모 착용시 보다 혈액을 통해 전달되는 체열의 상승이 억제되고 피부온과 심박수의 상승이 억제되는 것을 알수 있었는데 이것이 곧 혈압의 과다상승 방지와 인체부담의 경감으로 연결되었다고 사료된다. 4. 발한량은 유공안전모 착용시가 무공안전모 착용시보다 낮은 값을 나타내 보였다. 운동으로 인해 높아진 머리부분의 온도는 통풍을 목적으로 구멍을 뚫어 놓은 유공안전모를 착용했을 때 통기구멍으로 공기가 순환되어 온도가 과도하게 상승하는 것이 방지된다. 따라서 서열환경하에서의 체온상승이 억제됨에 따라 낮은 발한량을 나타내 보였다. 안전모내의 기후에서 유공안전모 착용시가 무공안전모 착용시보다 유의하게 더 낮은 온도를 나타내었고, 안전모내 습도는 운동시에 유공안전모 착용시가 무공안전모 착용시보다 다소 낮은 경향을 보였다. 통기를 목적으로 구멍을 뚫어 놓은 유공안전모를 착용함으로 인해 모자내의 더운 공기가 외부와 순환되어 무공안전모 착용시 보다는 온도가 낮게 나타났고 땀이 유공안전모의 구멍을 통해 증발을 일으켜 과도하게 습해지는 것을 방지 할 수 있었다. 5. 주관적 감각으로 온냉감, 습윤감, 쾌적감, 피로감을 측정하였는데 유공안전모 착용시가 무공안전모 착용시보다 더 낮은 주관적 감각 수치를 나타내어 착용감이 더 좋았음을 알 수 있었다. 또한 근력측정에서 무공안전모 착용시가 유공안전모 착용시 보다 평가 수치 가 낮게 나타나 더 피로한 것을 알수 있다. 이상의 결과에서 통기를 목적으로 구멍을 뚫어놓은 유공작업안전모가 심부온, 피부온, 혈압, 심박수, 발한량, 모자내 기후 등의 인체생리반응을 고려해 볼 때 더 바람직한 작업 안전모 형태라는 것을 알 수 있었다. 종래의 작업과 관련한 피복연구에서 작업복, 장갑, 신발에 대하여는 생리학적 연구가 이루어졌으나, 안전모에 관한 연구에서는 생리학적인 부분을 고려하지 않고 단지 안전 보호측면에서의 연구가 이루어졌을 뿐이었다. 따라서 서열환경하에서 머리부분의 쾌적성을 고려한 다양한 작업 안전모에 대한 계속적인 연구와 개발이 이루어진다면 물리적 측면에서 작업 안전을 만족시킬 뿐만 아니라 생리적 측면에서 체열 평형을 도모하여 작업 능률의 향상을 가져올 것이다.

병원에 입원한 노인의 무력감 현상 연구 (A Phenomenological Study for Hospitalized Elderly무s Powerlessness)

  • 최영희;김경은
    • 대한간호학회지
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    • 제26권1호
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    • pp.223-247
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    • 1996
  • This study was done to provide information which would lead to nursing care of the elderly being more holistically through an understanding of the phenomena of powerlessness based on the lived experience of powerlessness by the elderly, the meaning the elderly give to such phenomena, and what essence of powerlessness is. The methodology used in this study was Max Van Manen's phenomenological method based on the philosophy of Merleu-Ponty and a concerted approach was realized through the 11 steps suggested in the Van Manen's method. Data collection was done from March 2, 1995 to December 30, 1995. The subjects for this study were four elderly persons who lived with their families and who were over 60 years of age. Data were collected about the lived experience of the elderly, this researcher's experience of powerlessness, the linguistic meaning of powerlessness, idioms of the word or a feeling of powerlessness, and descriptions of powerlessness in the elderly as they appeared in the literature, are works, and phenomenological literature. All data were used to provide insights into the phenomena of powerlessness. Data about the experience of powerlessness by the elderly were collected through open interviews, participation, and observation. In the analysis of the theme of this study, the aspects of the theme, powerlessness in the elderly were clarified, thereby abstracting and finding meaningful statements by the elderly about their feeling of powerlessness, and then those significant statements were expressed as linguistic transformations. The summarized findings from the study are as follows : 1. Five meanings of powerlessness in the elderly were defined. 〈weakness〉, 〈dependence〉, 〈frustration〉, 〈worthlessness〉 and 〈giving up〉. 2. 〈Weakness〉 means that the elderly experience, not only their aging but also, their becoming weak and the loss of physical function frequently caused by diseases. 〈Dependence〉 means that the elderly experience dependence without any influence from the surroundings and that elderly patients who are hospitalized lose their autonomy, follow entirely their doctor's prescriptions, use aid equipment and directions, and depend only on those things. 〈Frustration〉 means that the elderly experience the loss of their roles from the past, there by feeling that there is no work for them to do anymore and therefore feel unable to do anything. 〈Worthlessness〉 means that the elderly experience the feeling of losing their social roles from the past, having no financial ability, thereby being a burden to their children or the people around them, and therefore regarding themselves useless. 〈Giving up〉 means that the elderly experience the feeling of closeness to death in the final stage of their lifetime, lose hope to be healed from their disease, and recognize the incontrollability of their own body. 3. From a general view of the meaning of the theme the powerlessness in the elderly-the most essential meaning of the theme is the 〈sense of loss〉. For the elderly are experiencing a sense of loss in the situation of being elderly and therefore being often hospitalized. Brief definitions of the five phenomena could be 〈weakness〉 meaning the loss of physical strength, 〈dependence〉 the loss of mentality caused by disease and hospitalization, 〈frustration〉 and 〈worthlessness〉 the loss of social performance caused by the loss of social functions from the past, and lastly 〈giving up〉 the loss of the controllability of such situations of aging and suffering disease. In light of the discussion above, it is understandable that the hospitalized elderly experience powerlessness not only as it related to their diseases but also to their normal aging, and this related to other characteristics of being elderly means that the 〈sense of loss〉 is the very essence of their powerlessness. 4. While most cases are of the normal elderly experiencing powerlessness in relation to their social network, cases of elderly who are hospitalized are of those experiencing powerlessness in relation to the loss of their physical desire. 5. The findings discussed above can serve as guidelines for nurses who take care of the ill elderly who are hospitalized and that can provide cues to appropriate nursing service, recognizing that the subjective experience of the objective age of the elderly is so important. Nurses can provide highly qualitative nursing service, based on their deep understanding of the suffering of the elderly due to feelings of powerlessness.

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사회적 기술 부족과 충동성으로 인해 또래갈등이 심한 분교아동의 상담사례 (Counseling Case Study of a Child with Peer Confliction due to Lack of Social Skills and Impulsiveness)

  • 이인선
    • 초등상담연구
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    • 제5권1호
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    • pp.227-253
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    • 2006
  • It seems common for students living at a small county and islands to experience psychological conflicts and be unaccustomed in the peer society because they are not familiar with peer interaction and social skills. This is a case study of L (hereinafter called L) who was grown up in the sheltered school at a small county. L was psychologically disturbed because he couldn't get along well in the transferred school. It is the reason why he had lived in the sheltered school at a small county, so he had not enough exposure to interact with peer and social skills. Sometimes he was obstinate irrationally and when he had trouble with friends, he threw something out or went out of school and tricked juniors dangerously. The fact of disperse with families, parent's indifference, and hate of older brother made L to have ill feeling against family. He had low motivation and low self confident in learning because of short attention time and accumulated poor learning progress. In this study, he was evaluated at various area, such as, intelligent, affective, personal and inter-personal, before counselling. To evaluated the effect of the counselling, K-WISC-III, KPRC, sentence filling test, social adaptation ability test, etc, were administered right after the counselling was over and 8 weeks later. For specific information gathering and analysing, observation diary and deepen counselling were accomplished by homeroom teacher, his mother, and his peers. To correct his problematic behaviors, 13 counseling sessions were accomplished for 6 months and those counselling sessions were recorded and analysed definitely. Followings are the result of this case study. First, he was recovered from the anxiety of inter-personal interaction and he started to interact with peers. The result of sac scale score of KPRC profile was lower than before as much as average student after counseling and 8 weeks later. This reveals that the distress against interpersonal relation have settled. Especially, through the result of sentence filing test, he seemed to feel attachment to peers and be positive, active in the relation of peer. For instance, he was active in the open class lesson and interacted well with peers. It could be said that he overcame the psychological distress comparing with previous time. Second, he could apologize to his peer and juniors for his fault. His attitude were well shown in the letter from an old friend at the sheltered school, average KPRC profiling score comparing with previous counseling time, and remarkable decrease of attack scale score of teacher and peer. Third, his view toward family turn out positive. He recognized his situation that he lived apart from family and even worried about his parent's financial difficulty. Through solving the confliction with his older brother, he could acquire the feeling of family reunion. Fourth, his learning motivation and self-confidence were increased. He confirmed his future positively and he might be judged more attentive because his intelligence index was higher than before as much as average student. With the main goal of this study, verification for effectiveness of counseling. understanding and helping problematic students such as L who lives at a small county and island through investigation of their real situation and problems with the method of counseling and socio-cultural analysis is worthwhile. Identification of ideal relationship with peer is related with positive self-conception, harmonic social adaptation and development of child. It is time to investigate easy adaptive in classroom and well-organised program to acquire general social skills for sheltered school students at a small county and islands.

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Establishing a Nomogram for Stage IA-IIB Cervical Cancer Patients after Complete Resection

  • Zhou, Hang;Li, Xiong;Zhang, Yuan;Jia, Yao;Hu, Ting;Yang, Ru;Huang, Ke-Cheng;Chen, Zhi-Lan;Wang, Shao-Shuai;Tang, Fang-Xu;Zhou, Jin;Chen, Yi-Le;Wu, Li;Han, Xiao-Bing;Lin, Zhong-Qiu;Lu, Xiao-Mei;Xing, Hui;Qu, Peng-Peng;Cai, Hong-Bing;Song, Xiao-Jie;Tian, Xiao-Yu;Zhang, Qing-Hua;Shen, Jian;Liu, Dan;Wang, Ze-Hua;Xu, Hong-Bing;Wang, Chang-Yu;Xi, Ling;Deng, Dong-Rui;Wang, Hui;Lv, Wei-Guo;Shen, Keng;Wang, Shi-Xuan;Xie, Xing;Cheng, Xiao-Dong;Ma, Ding;Li, Shuang
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권9호
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    • pp.3773-3777
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    • 2015
  • Background: This study aimed to establish a nomogram by combining clinicopathologic factors with overall survival of stage IA-IIB cervical cancer patients after complete resection with pelvic lymphadenectomy. Materials and Methods: This nomogram was based on a retrospective study on 1,563 stage IA-IIB cervical cancer patients who underwent complete resection and lymphadenectomy from 2002 to 2008. The nomogram was constructed based on multivariate analysis using Cox proportional hazard regression. The accuracy and discriminative ability of the nomogram were measured by concordance index (C-index) and calibration curve. Results: Multivariate analysis identified lymph node metastasis (LNM), lymph-vascular space invasion (LVSI), stromal invasion, parametrial invasion, tumor diameter and histology as independent prognostic factors associated with cervical cancer survival. These factors were selected for construction of the nomogram. The C-index of the nomogram was 0.71 (95% CI, 0.65 to 0.77), and calibration of the nomogram showed good agreement between the 5-year predicted survival and the actual observation. Conclusions: We developed a nomogram predicting 5-year overall survival of surgically treated stage IA-IIB cervical cancer patients. More comprehensive information that is provided by this nomogram could provide further insight into personalized therapy selection.

탈회된 법랑질에서 CPP-ACP의 재광화 깊이 (REMINERALIZATION DEPTH OF CPP-ACP ON DEMINERALIZATION HUMAN ENAMEL IN VITRO)

  • 최한주;최영철;김광철;최성철
    • 대한소아치과학회지
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    • 제35권2호
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    • pp.278-286
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    • 2008
  • 이 연구는 Casein phosphopeptides-amorphous calcium phosphate (CPP-ACP)paste에 의해 제공되는 Calcium(Ca)과 Phosphorous(P) 이온이 탈회된 법랑질 표면에 적용된 시간에 따라 침투되는 깊이와 Ca/P의 상대적 정량값을 평가하고자 하였다. Field Emission Scanning Electron Microscopy(FE-SEM)와 Energy Dispersive X-ray Spectrometer(EDS)를 이용하여 Ca/P 이온의 정량적 측정으로 탈회된 법랑질 내로의 침투깊이를 계측하였다. 교정치료를 위해 발거된 제 1소구치 치관 협측면의 중앙 1/3부위에 $4{\times}9mm$의 법랑질 window를 제외한 나머지 치관부위는 nail varnish로 도포하여 window 부위의 법랑질만 노출시킨 후, 모든 치아를 0.1M lactic acid로 7일 동안 탈회시켰다. 탈회된 각 치아의 정중앙을 장축에 따라 절단한 후 그 중 4개의 소구치 절편은 10배 희석된 CPP-ACP paste 용액에 각각 1, 2, 3 및 5주 동안 침지시켰고, 나머지 4개의 소구치 절편은 증류수에 동일 기간 침지시켰다. 각 절편을 window에 대해 수직으로 절단하여 건전 법랑질, 탈회된 법랑질 및 재광화된 법랑질의 깊이에 따른 Ca/P의 Spectrum Density Index(SDI)를 FE-SEM과 EDS로 계측하였다. 각 계측치를 Student's t test로 비교 평가하여 다음과 같은 결과를 얻었다. 1. Ca/P 이온이 법랑질 표면으로부터 약 $1050{\sim}1400{\mu}m$까지 침투하여 탈회 법랑질의 깊이인 $1050{\sim}1350{\mu}m$까지 재 광화되었다. 2. 1주군과 2주군의 재광화된 법랑질의 Ca/P SDI는 건전 법랑질보다 유의성 있게 높았으나(p<0.05), 3주군에서는 건전 법랑질보다 유의하게 낮았고(p<0.05), 5주군은 건전 법랑질과 유의한 차이가 없었다(p>0.05). 3. 모든 재광화된 법랑질 간에 Ca/P의 SDI는 유의한 차이가 없었다(p>0.05).

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변환기(變換期)에 있어서의 국제민간항공기구(國際民間航空機構)(ICAD)와 항공법(航空法) 발전(發展)의 최근(最近) 동향(動向) (The International Civil Aviation Organization and Recent Developments of Air Law in a Changing Environment)

  • 최완식
    • 항공우주정책ㆍ법학회지
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    • 제4권
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    • pp.7-35
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    • 1992
  • The expansion of air transport on a global scale with ever increasing traffic densities has brought about problems that must be solved through new multilateral mechanisms. Looking to the immediate future, air transport will require new forms of international cooperation in technical and economic areas. Air transport by its very nature should have been a counterforce to nationalism. Yet, the regulatory system in civil aviation is still as firmly rooted in the principle of national sovereignty as when it was first proclaimed at t-11e Paris Convention of 1919 and reaffirmed in the Chicago Convention. Sovereignty over the airspace has remained the cornerstone of relations between states in all respects of air transport. The importance of sovereignty over air space embodied in article 1 of the Chicago Conrenton also is responsible for restricting the authority of ICAO as an intergovernmental regulatory agency. The Orgenization, for all its extensive efforts, has only limited authority. ICAO sets standards but cannot enforce them; it devises solutions but cannot impose them. To implement its rules ICAO most rely not so much on legal requirements as on the goodwill of states. It has been forty-eight years since international community set the foundations of the international system in civil aviation action. Profound political, economic and technological changes have taken place in air transport. The Chicago Convention is living proof that staes can work together to make air transport a safe mode of travel. The law governing international civil auiation is principally based on international treaties and on other regulation agreed to by governments, for the most part through the mechanism of ICAO. The role of ICAO international standards and recommended practices and procedures dealing with a broad range of technical matters could hardly be overestimated. The organization's ability to develop these standards and procedures, to adapt them continuously to the rapid sate of change and development of air transport, should be particularly stressed. The role of ICAO in the area of the development of multilateral conventions on international air law has been successful but to a certain degree. From the modest starting-point of the Tokyo Convention, we have seen more adequate international instruments prepared within the scope of ICAO activities, adopted: the Hague Convention of 1970 for the suppression of Unlawful Seizure of Aircraft and the Montreal Convention of 1971 for the Suppression of Unlawful Acts against the Safety of Civil Aviation. The work of ICAO in the new domain of international law conventions concerning what has been loosely termed above as the criminal problems connected with international air transport, in particular the problem of armed aggression against aircraft, should be positively appreciated. But ICAO records in the domain of developing a uniform legal system of international carriage by air are rather disappointing. The problem of maintaining and developing the uniformity of this regulation exceeds the scope of interest and competence of governmental transport agencies. The expectations of mankind linked to it are too great to give up trying to restore the uniform legal system of international air carriage that would create proper conditions for its further growth. It appears that ICAO has, at present, a good opportunity for doing this. The hasty preparation of ICAO draft conventions should be definitely excluded. Every Preliminary draft convention ought to be sent to Governments of all member-States for consideration, So that they could in form ICAO in due time of their observation. The problom of harmonizing a uniform law of international air carriage with that of other branches of international transport should demand more and more of its attention. ICAO cooperation with other international arganization, especially these working in the field of international transport, should be strengthened. ICAO is supposed to act as a link and a mediator among, at times the conflicting interests of member States, serving the happiness and peace of all of the world. The transformation of the contemporary world of developing international relations, stimulated by steadily growing international cooperation in its various dimensions, political, economic, scientific, technological, social and cultural, continuously confronts ICAO with new task.

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미생물을 이용한 자철석으로부터 철 침출에 관한 연구 (Microbial Leaching of Iron from Magnetite)

  • 노열;오종민;서용재;장희동
    • 한국광물학회지
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    • 제19권4호
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    • pp.265-275
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    • 2006
  • 미생물을 이용한 원석 또는 폐석으로부터 인류에 유용한 원소 및 중금속의 용출은 초기 연구단계에 있는 새로운 생물학적 기술 중의 하나이다. 본 연구의 목적은 갯벌 퇴적물에서 분리한 미생물(Microcosm)을 이용하여 자철석으로부터 철의 용출 및 용출된 철의 생광화작용에 따른 2차 물질의 형성을 규명하고자 한다. 갯벌퇴적물에서 분리한 철 환원 박테리아(Microcosm)가 글루코스($10{\sim}20mM$)를 이용하여 성장하는 동안 자철석으로부터 철의 용출 및 2차 물질의 형성을 ICP, XRD, SEM-EDX 및 TEM을 이용하여 연구하였다. 미생물배지에 상업용 자철석(미생물배지 : 자철석 = 100 : 1)과 철환원 박테리아를 넣고 혐기성 및 호기성 조건하에서 철 용출 및 2차 물질의 형성실험을 실시한 결과, 철의 용출 실험동안 미생물배지의 Eh는 호기성 조건에서 +250 mV에서 -520 mV 까지 감소하고, pH 7.3에서 5.5까지 감소하였다. 혐기성 환경에서 박테리아의 활동에 따라 15일째 자철석으로부터 94 ppm의 Fe를 용출하였으며, 박테리아가 없는 혐기성 조건 하에서는 0.9 ppm의 Fe의 용출을 보여 주었다. 호기성 환경에서 박테리아의 활동에 따라 자철석으로부터 15일째 107 ppm의 Fe를 용출하였다. 배양을 시작한지 1개월이 지난 시점에서는 미생물배지에 용출되어 있는 Fe가 혐기성 조건에서는 57ppm의 Fe가, 호기성 조건하에서는 6.5 ppm의 Fe 각각 존재하였다. 박테리아가 배양되는 동안 용출된 철의 감소는 2차물질의 형성에 철이 소비된 것으로 사료되며, 호기성 조건하에서는 적갈색의 2차 물질 형성을 보여주었다. 미생물에 의한 자철석으로부터 철과 망간의 용출은 미생물의 활동에 따른 미생물배지의 열역학적인 조건(Eh/pH)의 변화 및 유기물의 산화에 따른 유기산의 형성에 기인한 것으로 사료된다. 미생물을 이용한 결정질의 자철석으로부터 철의 용출 및 비정질의 2차물질의 형성은 미생물의 퇴적물 내에서 철의 순환에 중요한 역할을 담당할 뿐만 아니라 미생물을 이용한 유용물질의 침출(Bioleaching) 및 생광화작용에 따른 광물의 합성 가능성을 시사한다.

제주도 주변해역 선망의 어획성능 향상에 관한 연구 -짐줄 체결 중 선망의 용적과 짐줄의 장력 변화 - (Studies on the Improvement of the Fishing Efficiency of Purse Seine in the Sea Area of Cheju Island -The Changes of Seine Volume and Tension in the Purseline During Pursing-)

  • 김석종
    • 수산해양기술연구
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    • 제35권2호
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    • pp.93-101
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    • 1999
  • 실험에는 제주도 주변해역에서 망선 120 톤 (총톤수) 급이 사용하고 있는 고등어 선망을 기준 스케일로 하고 그 축척비를 1/200 로 정하여 제작한 선망 모형을 이용했다. 그물실의 직경 (d : 0.45mm) 과 그물코의 발 길이 ( l : 4.5∼7.7 mm)의 비율 (d/l : 0.105∼0.058)이 다르고, 그 이외재료, 그물실의 굵기 등이 모두 같은 6종류의 무결절 그물감 (PES 28 tex ${\times}$2${\times}$2)을 사용해서 선망의 모형 I, II, III, IV, V 및 Ⅵ 형 그물을 만들었는데 뜸줄의 길이는 450 cm, 그물의 폭은 85 cm였다. 그리고 뜸 160g과 발돌 50g 을 부착해서 그물을 완성했다. 회류 수조의 수로 상에 투망 장치 및 짐줄 체결장치를 설치해서 정지 상태의 수중에 선망 그물을 투망한 후 짐줄을 체결하면서 상방과 전방에 설치한 비디오 카메라를 사용하여 그물의 운동상태를 촬영 녹화했다. 그리고, 용적변화에 대해서는 재생화면에서 그물에 표시한 측정점의 좌표를 화상해석 장치로 읽고 실험값을 구했으며, 장력변화에 대해서는 짐줄 체결장치에 부착된 로오드셀로 측정하고 저장된 자료를 사용하여 해석했는데, 그 결과는 다음과 같다. 1. 짐줄체결중 선망의 용적은 d/l 가 가장 작은 Ⅵ형 그물이 가장 작게 나타났으며 V, IV, III, II 및 I 형 순으로 작은 경향을 보였으며, 짐줄의 장력은 작게 나타났다. 2. 짐줄 체결시의 그물내부의 용적변화에 대해서는 다음의 실험식으로 나타낼 수 있었다. $CV_{t}$= 1- EXP [{2.79(d/l)+0.35}t-{33.37 (d/l)+0.57}] 3. 짐줄 체결시의 짐줄의 장력변화에 대해서는 다음의 실험식으로 나타낼 수 있었다. T=EXP {.57t + 13.36 (d/l)+2.97}모델 등이 있다. 본 연구에서는 인체 volunteer자료를 활용하여 용량-반응자료를 입력하고 용량-반응자료를 토대로 적합한 수학적 모델을 찾아내어, 선별한 모델의 적합도 검정을 실시하는 방법론 연구를 실시하였으며, 노출평가 자료와 용량-반응평가 결과를 연계하여 위해도를 결정하는 과정에 대해 연구하였다 이 밖에도 모델(Food MicroModel)을 이용하여 식품의 염도, 수분활성도, 온도, pH등의 조건에 따른 미생물의 성장률, 사멸률 등 변화를 예측할 수 있는 방법론 연구를 통해 식품의 최적 보관 조건등을 찾아내는 방법을 습득하였다. 미생물 위해성평가는 외국에서도 아직 초기 연구단계에 있으며 현재로서 사후조사자료인 역학자료보다 건강한 성인남자를 대상으로 한 volunteer 자료를 우선적으로 활용하고 있으나 노약자나 민감그룹에 대한 실험은 현실적으로 불가능하여 동물실험을 이용한 평가방법을 연구중에 있다. 추후 연구방향으로는 국내 volunteer들을 대상으로 한 미생물별 용량-반응결과를 토대로 population sensitivity를 비교할 수 있는 기초자료를 확보함으로써 미생물에 대한 인구집단의 반응 민감성 차이를 비교하고 시료채취 후 즉각적인 실험실적 분석이 가능토록하여 정확한 인체노출평가를 수행함으로써 미생물 위해성평가방법론을 식품미생물관리에 적용하는 것이다.으로 사료된다. 또한 재미 한인 사회에서의 대중매체를 통한 명절음식의 홍보와 재교육이 강화되어져야하겠다.m$1$^{\circ}C$에서 유지를 가열하는 경우에는 CLA의 항산화효과가 크게 나타났으며 그 정도는 BHT나 tocopherol과 거의 유사하였고 저온 저장시의 경우 보다 더 높은 항산화효과를 보였다can be used as a criterion where the resources for the investigation should be allotted

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