• 한국학교수학회논문집
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• 제13권3호
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• pp.381-395
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• 2010

학령 전 아이들은 형식적인 교육을 받지 않고서도 일상적인 경험이나 비형식적인 방법으로 수를 익히고, 계산을 한다. 따라서 학령 전 아이들의 수학적 능력에 대한 이해는 유치원 교육과 초등학교 저학년의 수학 학습 지도에 시사점을 줄 수 있다는 변에서 중요하다. 본 연구에서는 학령 전인 만 5세의 아이들이 사칙연산 문장제의 의미론적 측면의 문제 유형에 어느 정도의 해결 능력과 방법을 보이는가를 조사하였다. 연구 결과, 만 5세의 학령 전 아이들은 5보다 크고 10보다 작은 수로 구성된 사칙연산 문장제에 대하여 구체물을 이용한 비형식적 연산의 수행과 정신적 암산을 수행하는 방법을 통하여 문제를 해결할 수 있는 능력을 가지고 있음을 알 수 있었다. 이것은 학령 전 아이들의 수학적 경험을 위한 교육과정이나 프로그램을 체계적으로 구성하여 제시할 필요성을 제기한다.

• Communications for Statistical Applications and Methods
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• 제18권4호
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• pp.507-516
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• 2011

상관된 이항자료에 대한 일반화 이항모형들을 비교한 연구들은 고려한 모형과 비교기준에서 결과가 제한적이라는 측면이 있다. 이 연구는 모형선택의 가능한 지침을 제공하기 위해 모의실험을 통하여 모형별 적합도와 베르누이 시행의 성공확률 및 급내상관계수에 대한 ML추정량들을 비교하였다. 모수의 특정영역을 제외하고 포괄적 적합도나 추정량의 MSE 및 편의 등 성분적합에서는 대부분의 모형이 일정 수준의 경쟁적 관계에 있는 것으로 나타났다. 그러나 고려한 모형들 중 특히 일반화 확장베타이항모형 (Prentice, 1986)은 거의 모든 모수영역과 비교기준에 걸쳐 일관되게 양호한 수행력을 가지는 것으로 평가되었다.

• 한국초등과학교육학회지:초등과학교육
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• 제36권1호
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• pp.1-15
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• 2017

The purpose of this study is to analyze the problems of land and sea breeze model experiment that has presented in $5^{th}$ grade curriculum in chapter "Weather and our lives" and makes better model simulation so that learners can have better and more effective way to study it. To survey the opinions from dedicated teachers about land and sea breeze model experiment, we produced the survey through interview with science exclusive teacher from M elementary school. An elementary science education expert, 3 men of science EdD modified and complemented survey and started Delphi survey to 12 science teachers who have career teaching more than 3 years. The problems found in this survey were 'one heat bulb, short heating time, small temperature difference of water and sand, lack of class time, empty space between sand and water, back of transparent boxes, little amount of scent and the location of the it' etc. But the most of all, it is hard to see the successful result of the experiment. Based on these kinds of investigations, and lots of trial and error, redesigned the new model experiment that has the most similarity to the real one and high probability of success. According to this, it was able to see the smoke forms horizontal movement along the sand and the smoke goes in one circulation cycle. through this experiment, we made a conclusion that although those scientific experiments in textbook were developed through lots of considerations of expert, to consider the aspect of consumer, it needs to reach the educational agreement about simulation experiment so that It can lead to successful experiment and high quality education.

• Journal of Korean Neurosurgical Society
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• 제29권7호
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• pp.929-934
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• 2000

Objective : The results of secondary transsphenoidal surgery(TSS) for either residual or recurring pituitary adenomas have been reported to be unfavorable. To evaluate the effectiveness of secondary TSS, we analyzed the surgical results of residual or recurred pituitary adenomas in patients who underwent secondary TSS from 1992 to 1998. Material and Methods : Among the 95 patients who underwent TSS during this period, 14(15%) received repeated TSS. Two of the 14 patients underwent three TSS. Among the 11 patients with pituitary adenomas, three had nonfunctioning tumors ; six prolachnomas ; two GH-secreting adenomas. The remaining three patieats had craniopharyngioma, pituitary abscess and hemangioendothelioma respectively. The interval between the two surgical procedures ranged from one week to 33 months(mean ; 12 months). Causes of the secondary TSS were tumor recurrence in 11 patients, intentional staged operation in three, persistent disease despite medical therapy and CSF leak after initial operation in one respectively. Treatments prior to secondary TSS were medical treatment only in eight patients. Results : During the repeated operationtss some adhesion was noted in septal mucous membrane. The sphenoid cavity was filled with fibrous tissue which correlated with the methods of reconstruction of the sellar floor at the previous operation. There was no statistically significant difference in success rate of surgery between the initial and the second TSS(86% vs 81%). The complication rate was similar between the two procedures. There was no statistically significant factors affecting the results of second TSS. Conclusion : Transsphenoidal reoperation was regarded as a suitable approach for treating recurrent pituitary adenomas in spite of some degree of operative difficulties. In patients with transsphenoidally resectable tumor residuals or recurrences confirmed by magnetic resonance imaging, remissions can be obtained with high probability, especially in secondary surgery after an staged decompression.

• 정보처리학회논문지C
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• 제12C권4호
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• pp.465-472
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• 2005

IEEE 802.11 Wireless LAN은 무선 인터넷, 차세대 유무선 통합망, 홈네트워크망을 위한 필수적인 무선 액세스 기술이다. 그러나, IEEE 802.11 무선랜을 더 넓은 영역으로 확장하기 위해서는 사용자의 프라이버시를 제공하여야 한다. 현재 WEP이나 802.11i등의 보안 메커니즘이 MAC 계층에서 제안되어 있지만 이러한 보안 메커니즘이 VPN과 같이 사용될 경우. 보안 메커니즘의 중복적용이라는 결과가 나오게 되어 이를 해결하기 위해 1 비트를 인증비트로 사용하는 방식이 제안되었다. 본 논문에서는 기존의 1 비트를 인증 비트로 사용하는 방안에서 생길 수 있는 비트 동기화 실패와 그에 따른 패킷 낭비 문제를 제시하고, 동일 패킷의 수신 개수에 대한 카운터를 이용해 동기화를 한번에 맞춤으로써 이런 문제점들을 해결한 알고리즘을 제안한다. 또한, 성능 평가를 통해 제안하는 알고리즘이 패킷인증 성공률을 $98\%$까지 증가시킬 수 있으며 패킷 인증 비트 스트림의 효율성에서도 $97\%$까지의 개선된 성능을 나타냄을 검증하였다.

• 정보처리학회논문지B
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• 제15B권5호
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• pp.465-476
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• 2008

이질성, 이동성, 가변성 등의 특징을 갖는 유비쿼터스 컴퓨팅 환경에서 사용자의 의도에 맞도록 자율적이고 동적인 서비스를 제공하기 위해서는, 실시간의 상황을 고려하여 목적 달성에 필요한 서비스들을 합성할 수 있는 기법과, 이를 가능케 하는 효과적인 서비스 기술 및 관리 방법이 전제되어야 한다. 본 연구에서는, 도메인 내의 서비스를 추출하여 서비스 온톨로지로 구조화하는 메커니즘을 제안한다. 추출된 서비스는 제안한 서비스 규격에 따라 기술되고 온톨로지 내에서 계층적인 구조를 이루게 된다. 이를 근간으로 사용자는 다양한 추상화 레벨의 서비스를 사용하여 목표를 기술할 수 있고, 서비스 오버로딩 기법을 통해 실행 시에 가장 적합한 서비스가 선택된다. 또한, 요청한 서비스가 유효하지 않은 경우에도 서비스 온톨로지를 참조하여 대체 서비스를 찾을 수 있는 합성 방법을 제안한다. 구축한 서비스 온톨로지에 대한 실험 결과, 비구 조화된 서비스 리스트를 사용하는 것보다, 서비스 온톨로지를 사용함으로써 사용자의 목적 달성 성공률을 높일 수 있을 뿐만 아니라 서비스의 바인딩 시간도 감소시킬 수 있음을 보였다.

• 대기
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• 제29권4호
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• pp.439-450
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• 2019

Present weather plays an important role not only for atmospheric sciences but also for public welfare and road safety. While the widely used state-of-the-art visibility and present weather sensor yields present weather, a single type of measurement is far from perfect to replace long history of human-eye based observation. Truly automatic present weather observation enables us to increase spatial resolution by an order of magnitude with existing facilities in Korea. 8 years of human-eyed present weather records in 19 sites over Korea are compared with visibility sensors and auxiliary measurements, such as humidity of AWS. As clear condition agrees with high probability, next best categories follow fog, rain, snow, mist, haze and drizzle in comparison with human-eyed observation. Fog, mist and haze are often confused due to nature of machine sensing visibility. Such ambiguous weather conditions are improved with empirically induced criteria in combination with visibility and humidity. Differences between instrument manufacturers are also found indicating nonstandard present weather decision. Analysis shows manufacturer dependent present weather differences are induced by manufacturer's own algorithms, not by visibility measurement. Accuracies of present weather for haze, mist, and fog are all improved by 61.5%, 44.9%, and 26.9% respectively. The result shows that automatic present weather sensing is feasible for operational purpose with minimal human interactions if appropriate algorithm is applied. Further study is ongoing for impact of different sensing types between manufacturers for both visibility and present weather data.

• 한국정보전자통신기술학회논문지
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• 제9권6호
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• pp.584-590
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• 2016

본 논문에서 제안하는 "도심환경에서 통신 단절 예방을 위한 RRPS(Priority Scheduling and Multi Path Routing Protocol)"에서는 밀집도에 따라 통신의 단절이 빈번하게 일어나는 도심환경의 V2I 및 V2V통신의 단절을 최소화 하기 위하여, RSU의 관리 영역인 Start Line, End Line을 이용하여 End Line에 도달하기 전에 요청 메시지에 대한 우선순위를 적용하여 우선순위가 제일 높은 요청데이터를 먼저 처리할 수 있도록 하는 RRPS(RSU Request Priority Scheduling)알고리즘을 설계를 제안한다. 결과적으로 본 논문에서 제안하는 RRPS는 RSU내에 정보를 요청한 차량의 메시지에 대하여 우선순위 스케줄링을 적용하여 V2I의 처리효율을 향상하고, 통신 단절을 예방하여 전송 성공확률을 향상시키는 효과를 갖는다.

• Childhood Kidney Diseases
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• 제19권1호
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• pp.31-38
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• 2015

Purpose: We evaluated the long-term results of endoscopic Deflux$^{(R)}$ injection for treating vesicoureteral reflux (VUR) in children. Methods: Between September 2004 and September 2014, 243 children (137 boys and 106 girls) with a mean age of 53 months underwent Deflux$^{(R)}$ injection. Our clinical protocol included radionuclide voiding cystography (RNC) at postoperative 3 months, 1 year and 3 years to assess the VUR resolution. Results: The cure rates at 3 months, 1 year, and 3 years by patients were 70.8%, 64.3%, and 65.6% for the total patients and 79.2%, 75.2%, and 76.4%, for the ureters, respectively. The recurrence rate of postoperative febrile urinary tract infection (UTI) was 20% in patients without VUR at postoperative 1 year. Twenty patients undergoing ureteroneocystostomy (UNC) significantly had younger age (P=0.003), higher VUR grade (P<0.001), and lower success rates of Deflux$^{(R)}$ injection (P<0.05). On univariate analysis, older age (P=0.014) and lower grade of VUR (P=0.031) were the significant predictors of a successful outcome. But there was none on multivariate analysis. Younger age, especially age of 0-12 month-old, was the only significant predictor of postoperative febrile UTI recurrence on both univariate and multivariate analysis. Conclusion: Deflux$^{(R)}$ injection is efficacious with a low complication rate for the anti-reflux procedure in children. There is low recurrence rate of UTI though VUR persists, and high probability of no VUR at 3 years if no VUR at 1 year. It is recommendable not to perform follow-up RNC at 3 years routinely if no VUR at 1 year.

• 경영과학
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• 제27권2호
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• pp.81-95
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• 2010

There is an increasing interest in contents such as movie, drama and game using transmedia storytelling. It includes Le Grand Chef, The War of Flower, Dae Jang Geum, The Matrix, Harry Potter and The Lord of the Rings. However, transmedia contents have not always been successful. To study the factors affecting possible outcomes of transmedia storytelling, we analyzed the intention on transmedia of potential consumers who have not been exposed to transmedia contents before. To this end, we investigated two different cases : first, potential customer intention to watch dramas which will be produced after launching comic-based movies; second, potential customer intention to see movies which will be made after broadcasting comic-based TV dramas. In each case, we analyzed the outcomes from potential customers by applying several variables including gender, exposure to the original and components of contents (plot, quality of act and music etc). Our study showed that potential customers prefer movies or TV dramas with quality of acting, directing, casting and storylines. Interestingly, the quality of acting is more important in dramas than in movies and casting is an appealing factor to potential customers in movies. In TV drama cases, potential customers have high watching intentions when they read the original content. Among them, male potential customer have low watching intentions on TV drama when they did not read the original content. However, female potential customers have high watching intentions on TV drama regardless of the previous exposure to the originals. In movie cases, female potential customers have higher intentions on seeing movies than male. These results suggest that one needs to consider several factors such as casting, acting and gender for generating transmedia contents with a high probability of success.