• 제목/요약/키워드: prime factors

검색결과 190건 처리시간 0.024초

신경모세포종 -15년간 한 병원에서의 임상적 경험- (Neuroblastoma - Experience in One Center -)

  • 김대연;김성철;김인구
    • Advances in pediatric surgery
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    • 제11권2호
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    • pp.99-106
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    • 2005
  • Neuroblastoma treatment remains challenging, but treatment has become more effective due to the establishment of clinical and biological variables that determine prognostic risks. Initially, stage and age were the prime determinants of survival used in clinical practice. Risk-based therapy currently is the hallmark of neuroblastoma treatment. This study reviews one center's experience with the management of neuroblastoma. Sixty-three patients with neuroblastoma were treated from 1989 to 2003. All patients were graded according to the International Neuroblastoma Staging System (INSS) at diagnosis. There were 37 boys and 26 girls. The median age was 2.14 years (range, 33 days-10.2years). The primary site was the adrenal gland in 47, dumbbell shape extending into spinal canal in 6, retroperitoneum in 5, mediastinum in 3, and other sites in 2. The probability of 5-year overall survival (OS) and event free survival (EFS) were 46.7 % and 44.2 % by Kaplan-Meier method. According to INSS, there were stage 1 in 2 cases, stage 2 in 5, stage 3 in 12, stage 4 in 42, and stage 4s in 2. There were statistically significant differences in the survival rates between patients with stage1, 2 and stage 3, 4(P<0.05). For the stage 3 and 4, the extents of surgical resection, determined from the operative records and pathologies, were complete resection in 17 cases, minimal residual in 15, and partial resection 11, and the 5-year OS rate was 57.8, 51.4, and 13.6 %, respectively. There is a trend toward higher OS with more complete resection (P<0.05). We conclude that age and stage at diagnosis are prognostic factors, and complete excision of the primary tumor can provide better prognosis for patients with stage 3 and 4 neuroblastoma.

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Mutual Authentication and Secure Session Termination Scheme in iATA Protocol

  • Ong, Ivy;Lee, Shirly;Lee, Hoon-Jae;Lim, Hyo-Taek
    • Journal of information and communication convergence engineering
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    • 제8권4호
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    • pp.437-442
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    • 2010
  • Ubiquitous mobile computing is becoming easier and more attractive in this ambient technological Internet world. However, some portable devices such as Personal Digital Assistant (PDAs) and smart phones are still encountering inherent constraints of limited storages and computing resources. To alleviate this problem, we develop a cost-effective protocol, iATA to transfer ATA commands and data over TCP/IP network between mobile appliances and stationary servers. It provides mobile users a virtual storage platform which is physically resided at remote home or office. As communications are made through insecure Internet connections, security risks of adopting this service become a concern. There are many reported cases in the history where attackers masquerade as legitimate users, illegally access to network-based applications or systems by breaking through the poor authentication gates. In this paper, we propose a mutual authentication and secure session termination scheme as the first and last defense steps to combat identity thief and fraud threat in particular for iATA services. Random validation factors, large prime numbers, current timestamps, one-way hash functions and one-time session key are deployed accordingly in the scheme. Moreover, we employ the concept of hard factorization problem (HFP) in the termination phase to against fraud termination requests. Theoretical security analysis discussed in later section indicates the scheme supports mutual authentication and is robust against several attacks such as verifiers' impersonation, replay attack, denial-of-services (DoS) attack and so on.

TI-73 계산기를 활용한 초등 5학년 수학 영재 학급의 수업 분석 (An Analysis of Using TI-73 Calculator for the 5th Grade Students in an Elementary Math Gifted Class)

  • 강영란
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제16권3호
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    • pp.315-331
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    • 2013
  • 본 연구는 포항시에 소재하는 초등학교 5학년 수학 영재 학급 학생 20명을 대상으로 TI-73 계산기를 활용하여 좌표, 백분율, 소인수분해에 대한 수업의 질적 자료를 분석하였다. 이를 통해 계산기 활용이 영재 학생들의 학습에 어떤 영향을 미치는지 살펴보고, 계산기를 활용한 수업에 대한 시사점을 얻고자 하였다. 연구를 위해 이들 각 차시의 내용에 대해 활동지를 각각 제작하였고, 3주에 걸쳐 80분씩 3차례 수업을 진행하였다. 자료 분석을 위해 동영상 촬영, 학생과의 인터뷰, 문서 자료 등을 수집하였으며, 수집된 동영상, 녹음 자료는 녹취록을 작성하여 이를 토대로 코딩 작업을 하였다. 코드의 결합과 분해를 반복함으로써 초등 수학 영재 학생들의 계산기 사용에 대한 주제를 도출하였다. 본 연구 결과에 따르면, 의사소통을 매개하는 계산기, 지필환경의 범위를 넘어선 과제 해결을 위한 계산기, 계산기 활용에 대한 남녀의 성차 존재, 학습에 영향을 주는 계산기의 제한점이라는 네 가지 주제를 도출할 수 있었다.

중소병원 간호사의 비판적 사고성향과 셀프리더십이 임상수행능력에 미치는 영향 (Influence of Nurses' Critical Thinking Disposition and Self-Leadership on Clinical Competency in Medium Sized Hospitals)

  • 이선화;이은자
    • 임상간호연구
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    • 제24권3호
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    • pp.336-346
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    • 2018
  • Purpose: This study was conducted to identify nurses'critical thinking disposition, self-leadership and clinical competency in small to medium sized hospitals less than 300beds. Methods: Data were collected using the questionnaire from 227 nurses in Incheon city and Gyeonggi province from March to April, 2017. The data were analyzed using t-test, ANOVA and $Scheff{\acute{e}}^{\prime}s$ test to identify differences in critical thinking disposition, self-leadership and clinical competency. Pearson correlation coefficients were used to identify the correlation among the study variables, and multiple regression was used to identify factors contributing to clinical competency. Results: There were significant differences in critical thinking disposition according to age, marital status, clinical career, career in currently working department and education about leadership. Significant differences in self-leadership were identified according to marital status, work position, working department, work type, education about leadership, and turnover intention. Clinical competency was significantly different depending on age, education, monthly income, work position, career in currently working department, work type, education about critical thinking disposition and education about leadership. Clinical competency was positively correlated critical thinking disposition and self-leadership. Critical thinking deposition, monthly income and self-leadership explained 30.1% of clinical competency of nurses working in small to medium sized hospitals. Conclusion: The results of this study suggest that we need to improve nurses'critical thinking disposition, self-leadership, and the clinical competency.

Al 첨가 TWIP강에서의 지연파괴에 대한 변형유기 마르텐사이트 변태의 영향 (Effects of the Strain Induced Martensite Transformation on the Delayed Fracture for Al-added TWIP Steel)

  • 김영우;강남현;박영도;최일동;김교성;김성규;조경목
    • 대한금속재료학회지
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    • 제46권12호
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    • pp.780-787
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    • 2008
  • For the advanced high strength steels (AHSS), high-manganese TWIP (twinning induced plasticity) steels exhibit high tensile strength (800-1000 MPa) and high elongation (50-60%). However, the TWIP steels need to be understood of delayed fracture following the cup drawing test. Among the factors to cause delayed fracture, i.e, martensite transformation, hydrogen embrittlement and residual stress, the effects of martensite transformation (${\gamma}{\rightarrow}{\varepsilon}$ or ${\gamma}{\rightarrow}{\alpha}^{\prime}$) were investigated on the delayed fracture phenomenon. Microstructural phase analysis was conducted for cold rolled (20, 60, 80% reduction ratio) steels and tensile deformed (20, 40, 60% strain) steels. For the Al-added TWIP steels, no martensite phase was found in the cold rolled and tensile deformed specimen. But, the TWIP steels with no Al addition indicated the martensite transformation. The cup drawing specimens showed the martensite transformation irrespective of the Al-addition to the TWIP steel. However, the TWIP steel with no Al exhibited the larger amount of martensite than the case of the TWIP steel with Al addition. For the reason, it was possible to conclude that the Al addition suppressed the martensite transformation in TWIP steels, therefore preventing the delayed fracture effectively. However, it was interesting to note that the mechanism of delayed fracture should be incorporated with hydrogen embrittlement and/or residual stress as well as the martensite transformation.

WAP에서 사용 가능한 ElGamal 기반의 비대화형 불확정 전송 프로토콜 (Non-Interactive Oblivious Transfer Protocol based on EIGamal in WAP)

  • 정경숙;홍석미;정태충
    • 정보보호학회논문지
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    • 제13권1호
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    • pp.11-18
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    • 2003
  • 인터넷이 무선 구간으로 확대됨에 따라 보안측면에서도 효율적이고 안전한 새로운 보안 프로토콜이 필요하게 되었다. 본 논문에서는 이러한 요구를 해결하기 위해 통신량이 적을 뿐만 아니라 신뢰 기관이 비밀키를 보유함으로 인해서 발생하는 문제점을 해결할 수 있는 새로운 프로토콜을 제안하고자 한다. 이 프로토콜은 비대화형 불확정 전송 프로토콜로서 기존의 안전도가 검증된 EIGamal 공개키 알고리즘을 기반으로 하였다. 제안된 프로토콜은 불확정 전송 프로토콜이므로 서버와 클라이언트간의 통신량을 줄일 수 있고, 챌린지 선택 비트(challenge selection bit)를 사용하여 클라이언트가 서버에 인증되는 확률을 줄임으로서 프로토콜의 효율성을 높였다. 또한 이중지수승(double exponentitation)을 사용함으로써 메시지를 복호화 할 경우 기존의 이산대수나 소인수문제보다 어렵게 되므로 프로토콜의 안정성을 높일 수 있다.

위치종속임분조사(位置從屬林分調査)에 의한 개체목(個體木)의 경쟁지수(競爭指數) 및 흉고직경생장(胸高直徑生長) 추정(推定) (Estimating the Competition Indices and Diameter Growth of Individual Trees through Position-dependent Stand Survey)

  • 이우균
    • 한국산림과학회지
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    • 제85권3호
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    • pp.539-551
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    • 1996
  • 본 연구에서는 위치종속조사가법에 의해 소나무임분에서 조사된 자료로부터 임목의 크기 및 경쟁목과의 거리를 함께 고려한 개체목차원의 거리종속경쟁지수와 전통적인 임분차원의 밀도척도를 추정하고 이들을 흉고직경생장과 비교하여 경쟁상태에 대한 설명력을 검토하였으며, 경쟁지수가 영향변수로 고려된 개체목 흉고직경생장식을 유도하였다. 경쟁목선정방법에 있어 경쟁치단각도를 30도로 설정했을 때의 경쟁지수가 흉고직경생장과 기장 높은 상관관계를 보인 반면, 경쟁구역거리는 흉고직경생장추정에 대한 경쟁지수의 설명력에 미미한 영향을 미치는 것으로 나타났다. 개체목별 거리종속경쟁지수에 근거한 대부분의 임분경쟁지수들은 임분의 경쟁상태를 비슷하게 나타내는 것으로 평가되었다. 임령과 지위지수의 영향을 배제한 상태에서의 편상관분석결과 Alemdag의 평균경쟁지수 및 상대공간지수가 흉고직경과 가장 높은 연관성을 나타냈는데, 이중 개체목의 위치를 파악하지 않고도 비교적 손쉽게 파악될 수 있는 상대공간지수가 임분의 평균흉고직경을 추정하는데는 좀더 적합한 것으로 판단되었다. 개체목차원의 거리종속 경쟁지수중에서, 지위 및 흉고직경의 영향을 배제시킨다면 Hegyi의 경쟁지수가 흉고직경생장과 가장 밀접한 영향관계에 있는 것으로 밝혀졌다. 이로부터 Hegyi경쟁지수 및 임령, 우세목수고, 개체목의 흉고직경을 영향인자로 하는 다음과 같은 흉고직경생장식을 유도하였다. $$dbh^{\prime}=3.975362676{\cdot}age^{-1.099274613}{\cdot}ho^{0.199893990}{\cdot}dbh^{0.269430865}{\cdot}HgCI^{-0.353643587}$$ 위의 식은 다른 조건이 같다면 지위지수는 흉고직경생장에 유리한 영향을 미치는 반면 임령 및 경쟁지수의 증가에 의해서는 흉고직경생장이 둔화된다는 일반생장법칙에 부합되어 흉고직경생장식으로 적합하다고 판단되며, 단목생장모델을 위한 함수식으로 활용될 수 있다.

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인삼재배 분야의 과거 20년 연구 (Research on Ginseng Production During the Past 20 years)

  • 밝훈
    • Journal of Ginseng Research
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    • 제20권4호
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    • pp.472-500
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    • 1996
  • Researches on mineral nutrition, physiology and phyrsiological diseases, . cultivaction methods. brceding. pest control quality management and extension during 1976-1995 in Korea were reviewed Review in brceding and pest control was restricted to the researches directely related to cultivaction. Mineral nulrient up take. partion and varicos factors such as top dreasing. Light intersity etc. and interrelationship between minerals were investigated. Top dressing was not effective due to low minera1 requorement Physiological characteristics on tempelature light and water were well elucidated and applied to assess traditional cultivation method and its inovation. Photosyrnthetic pigments. light harvest proteins and activity of related enzymes were studied. In nitrogen metabolism arginine, praline, ammonium, threonine appeared to have important role in re growth of shoot Saponin metabolism was studied in relation to growth and new ginsenosides were found but physiological role of saponin was not clearly elucidated yet Endogenous growth regulators were reported and various erogenous growth regulators were studied for growth stimulation. short stem and seed pruning etc. Various physiological diseases were investigated for cause and control measures were established. Water culture was little studied Forest culture was studied but not retched the recommendable stage Drip irrigation straw mulching. seasonal shading and soil preparation method including soil fertility adjustment were established for practical application. Shading materials completely changed to polyethylene net and materials of polymers The research on ginseng cultivation in paddy field opened the way to establish the permanent ginseng cultivation plantation Ginseng harvester and seeder were developed in the late 1950s. Transplanted and many other machines were developed in the early 1990s. In ginseng breeding only pure line selection was of practical significance several verities were at the stage of seed propagation at ginseng plantations. Mutation breeding (${\gamma}$-ray. X-ray chemicals) was not successful. The research on plantlet formation through tissue culture was a little progressed but still far behind to vegetative propagation. Disease control research was concentrated in the isolation and identification of pathogans. their ecological charactelistics and biological control and soil humigation. Potato root rot nematodes was found and control method was established. Insect and small animal control research was greatly progresses in identification, ecological investigation, and ecological and physical control. Weed control was less important due to the development of mulching method of ridge and ditch. Quality factors of raw ginseng in relation to red ginseng process were extensively studied. Traditional quality measures were elucidated in accordance with modern analytical chemistry resulting in the importance of peptides in the centrat part rather than ginsenosides For large root production growth promoting rootzone micrcorganisms (PGPRM) were isolated and active compounds were identified. Field test on PGPRM was on going. Varictus methods formality improvement through cultivation were developed. Management research of ginseng production was rare Extension was active throuch official and private organizations and through workshop for the extension specialists, and direct lectures to grower's. Extension services made the researcher to understand the existing problems at grower's fields. Research environment for ginseng production was in prime time only for three years when Korea Ginseng Research Institute was established then gradually aggravated.

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해운산업 수익성 제고 투자의사결정 모델구축에 관한 연구 - 부정기선 영업을 중심으로 - (A Building of Investment Decision Model for Improving Profitabilty of Tramper Shipping Business)

  • 김원재
    • 한국항만경제학회지
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    • 제27권2호
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    • pp.297-311
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    • 2011
  • 본 논문은 투자수익성을 극대화 할 수 있는 건화물선 운항기업의 해운투자 의사결정 모델을 제시하는 것이 핵심 내용이다. 얼마전 우리나라 4위 해운기업인 대한 해운(주)가 법정 관리를 신청해 큰 충격을 주었는데, 그 이유를 살펴보면 전적으로 투자 의사결정이 잘못된 데 기인한다. 즉 대한해운(주)는 해운 경기가 피크에 이른 2007, 8년도에 집중적으로 산물선을 장기용선 방식의 투자확충 의사결정을 내렸으나, 2009, 10년도에 부정기선 운임지수가 거의 1/10 수준으로 폭락하여 막대한 손실을 보아 결국 자금압박으로 회사가 부도 상태에 이르게 되었다. 이러한 문제는 지난 1980년대 초에도 발생된 바 있으나 여전히 반복되고 있다는 사실이 안타깝다. 따라서 본 논문은 해운 경기가 호황에 있을 때 오히려 일정 선박을 매각하고 필요한 선복량은 단기 용선하여 향후의 경기변동 상황에 대처하도록 하는 의사결정을 말한다. 즉, 해운 경기가 불황국면에 있을 때는 조선경기도 하락 하는 만큼 저가로 선박을 매수 또는 발주하고 서서히 해운 경기가 회복되고 본격적인 상승기에 역시 선가도 급격히 상승하는 시점에 일정 비율의 보유선박을 매각 처분하여 선박 매매차익을 실현하고 다시 경기가 하강한 시점에서 선박을 재매입하는 순환적인 투자 의사결정 모델이 건화물선 해운기업의 수익성 제고에 크게 기여할 수 있다고 본다. 이때 고객서비스 유지를 위해 필요한 선복량은 단기 용선으로 대체하여 가급적 선박 보유 비중을 낮추는 의사결정이 매우 중요한데, 이러한 전략적 투자의사결정 모델은 자본집약적 산업인 해운기업의 재무위험과 영업위험을 모두 낮출 수 있게 된다는 것이 논문의 핵심이다.

티벳의학에 대한 연구 - "사부의전(四部醫典).근본의전(根本醫典)"을 중심으로 (Study on "Four Tantras", the Prime Textbook of Tibetan Medicine)

  • 장은영;윤창열
    • 대한한의학원전학회지
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    • 제11권1호
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    • pp.416-512
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    • 1998
  • The following conclusions are obtained from the studies on the chapters concerning phisiology, pathology, daily conduct, materia medica, pulse, and urinalysis from , of the "Four Tantras". 1. The theoretical basis forming the Tibetan Medicine is the substance of phlegm, bile, and wind each of which is divided into five kinds. These phisiological substances can be transformed into pathological factors when certain environment is formed. 2. In embryology, the semen of the father and menstral blood of mother is considered the most important condition in conception, and the Five factors are regarded as important. There is a detailed explanation of development of the fetus while it stays in the womb of mother during 38weeks, such as the formation of the viscera, channels, sense organs, etc. 3. There is metaphor which compares the human body with the king's palace. With the development of human anatomy, there is the detailed anatomical picture of anterior and posterior aspects of human body. And also there is the measurement of physiological constitution and the three fluids. 4. In division of the channels, they concerned the now of the blood and distribution of the nerve fibers, and each channel is connected with one another. The division of the cannel is namely embryonic channel, channel of existence, channel of connection, and the course of life principle. 5. The seven bodily constituents and three factors of phlegm, bile, and wind are important in sustaining the life of human body as well as growth and maturization, and when their equilibrium is broken, the human body is degnerated, and finally death comes. 6. The signs of death is divided into distant sign, remote sign, certain sign. and uncertain sign, and is used as a clue in diagnosis of the disease. Especially there is a mention about the mechanism of the dreams, and different dreams according to the condition of the patient. 7. In pathology, there is the cause of the disease, the environmental factors which can induce disease, the path by which disease come into the human body, the characteristics of the disease, and the kinds of disease. 8. There is a mention about the conduct, and it is divided into the daily conduct, the mental attitude, and the side-effects which can occur when one puts up with the physiological actions of the body. 9. The daily diet is divided into food and beverage. The food is divided again into grain, meat, fat, boiled food, and spiced food, and the beverage into milk, water, and wine. 10. The pulsation should be taken in lift hand to diagnose heart, small intestine, stomach, spleen, kidney, reproductive organ, and in right hand jungs, large intestine, liver, gall bladder, kidney, and bladder. In the healthy person, the pulse moves 5times in one perspiration, and the type of pulse is constant while the pulse moves 100times. But unhealthy person's pulse is different from this. The urinalysis is the unique part of Tibetan Medicine, and is important in examination of the disease. One should decide which of the three factors are dominant by the obervation of the color, amount of the steam and how long it lasts, odour, foam, and the shape of the swirl in three different states when the urine is hot, warm, and cold. One can determine the life of the patient and which viscera is the cause of the disease by the pulse, and whether the nature of the disease is hot or cold by the urinalysis. 11. The materia medica contains gemstones, minerals, plateau medication, and meat products.

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