• Wind and Structures
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• 제10권3호
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• pp.287-300
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• 2007

Wind action is a factor of fundamental importance in the structural design of light or slender constructions. Codes for structural design usually assume that the incident mean wind velocity is parallel to the ground, which constitutes a valid simplification for frequent winds caused by meteorological phenomena such as Extratropical Storms (EPS) or Tropical Storms. Wind effects due to other phenomena, such as thunderstorms, and its combination with EPS winds in so-called squall lines, are simply neglected. In this paper a model that describes the three-dimensional wind velocity field originated from a downburst in a thunderstorm (TS) is proposed. The model is based on a semi empirical representation of an axially-symmetrical flow line pattern that describes a stationary field, modulated by a function that accounts for the evolution of the wind velocity with time. The model allows the generation of a spatially and temporally variable velocity field, which also includes a fluctuating component of the velocity. All parameters employed in the model are related to meteorological variables, which are susceptible of statistical assessment. A background wind is also considered, in order to account for the translational velocity of the thunderstorm, normally due to local wind conditions. When the translation of the TS is caused by an EPS, a squall line is produced, causing the highest wind velocities associated with TS events. The resulting vertical velocity profiles were also studied and compared with existing models, such as the profiles proposed by Vicroy, et al. (1992) and Wood and Kwok (1998). The present model predicts horizontal velocity profiles that depend on the distance to the storm center, effect not considered by previous models, although the various proposals are globally compatible. The model can be applied in any region of interest, once the relevant meteorological variables are known, to simulate the excitation due to TS winds in the design of transmission lines, long-span crossings, cable-stayed bridges, towers or similar structures.

• 한국컴퓨터정보학회논문지
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• 제16권5호
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• pp.135-145
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• 2011

오늘날 센서 기술의 발전 및 보급으로 인해 USN 기반의 실시간 모니터링 응용에서의 센서 데이터 처리 시스템에 대한 연구가 활발히 진행 되고 있다. 센서 데이터는 시간에 따라 빠르게 변화하고 연속적인 저수준 상태의 방대한 양의 데이터를 생성하는 특성을 갖는다. 하지만 엔드유저는 상대적으로 고수준 상태의 데이터에 관심이 있기 때문에 빠르게 변화하고 연속적인 대량의 저수준 센서 데이터를 효과적으로 처리하는 시스템이 필수적이다. 본 논문에서는 USN 기반의 화재감시 응용에서 OLAP(On-Line Analytical Processing) 기술을 이용한 다차원 분석 질의 처리 기능과 학습기반 분류기를 통한 이상치 탐지 기능을 제공하는 센서 데이터 처리 시스템을 제안한다. 실험 시나리오를 통해 우리의 센서 데이터 처리 시스템에 대한 타당성을 검증하며 실험에 필요한 다양한 센서 데이터는 자체 개발한 센서 데이터 생성기를 이용한다.

• 임상간호연구
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• 제26권2호
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• pp.265-273
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• 2020

Purpose: The purpose of this study was to test the predictive validity of the Fall Assessment Scale-Korean version (FAS-K) and to find the most appropriate cutoff score to screen high-risk fall groups in adult patients in general hospitals in Korea. Methods: We performed a prospective evaluation study in medical and surgical ward patients at two major general hospitals in Seoul. Data were collected from Nov. 1, 2018 to Feb. 28, 2019, nurses performed 651 observation series. The researcher measured the fall risk assessment score by applying FAS-K, MFS (Morse Fall Scale), and JHFRAT (Johns Hopkins Hospital Fall Risk Assessment tool) to the patients twice a week between 10 am and 12 noon. Data were analyzed using Pearson's corelation coefficients, and the sensitivity, specificity, predictive value, and the area under the curve (AUC) of the three tools. Results: The FAS-K was positively correlated with the MFS (r=.70, p<.001) and the JHFRAT (r=.82, p<.001). According to the receiver operating characteristics (ROC) curve analysis of the FAS-K, sensitivity, specificity, and positive and negative prediction values were 85.3%, 49.4%, 8.5%, and 98.4%, respectively, when the FAS-K score was 4. Therefore, the cut-off score of the FAS-K to identify groups with high fall risk was 4. Conclusion: The FAS-K is a valid tool for measuring fall risk in adult inpatients. In addition, the FAS-K score, 4, can be used to identify high-risk fall groups and know specific points in time to provide active interventions to prevent falls.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제39권
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• pp.13.1-13.8
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• 2017

Background: Oronasal/antral communication, loss of teeth and/or tooth-supporting bone, and facial contour deformity may occur as a consequence of maxillectomy for cancer. As a result, speaking, chewing, swallowing, and appearance are variably affected. The restoration is focused on rebuilding the oronasal wall, using either flaps (local or free) for primary closure, either prosthetic obturator. Postoperative radiotherapy surely postpones every dental procedure aimed to set fixed devices, often makes it difficult and risky, even unfeasible. Regular prosthesis, tooth-bearing obturator, and endosseous implants (in native and/or transplanted bone) are used in order to complete dental rehabilitation. Zygomatic implantology (ZI) is a valid, usually delayed, multi-staged procedure, either after having primarily closed the oronasal/antral communication or after left it untreated or amended with obturator. The present paper is an early report of a relatively new, one-stage approach for rehabilitation of patients after tumour resection, with palatal repair with loco-regional flaps and zygomatic implant insertion: supposed advantages are concentration of surgical procedures, reduced time of rehabilitation, and lowered patient discomfort. Cases presentation: We report three patients who underwent alveolo-maxillary resection for cancer and had the resulting oroantral communication directly closed with loco-regional flaps. Simultaneous zygomatic implant insertion was added, in view of granting the optimal dental rehabilitation. Conclusions: All surgical procedures were successful in terms of oroantral separation and implant survival. One patient had the fixed dental restoration just after 3 months, and the others had to receive postoperative radiotherapy; thus, rehabilitation timing was longer, as expected. We think this approach could improve the outcome in selected patients.

• 한국동물학회지
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• 제32권2호
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• pp.75-83
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• 1989

한국 및 일본산 버들치속 어류의 유전적 변이, 종의 분류학적 위치 및 계통변화를 구명하기 위하여 전기영동법을 이용, 26개 유전자를 검출 분석하였다. 버들치속 어류의 평균 유전적 변이 정도는 타 어류군에 비하여 낮은 편이었다. 분류상 문제시 되어 오던 한국산 M. lagowskii와 M. oxycephalus 및 일본산 M. steindachneri와 M. jouyi는 각 종 특유의 genetic markers를 갖고 있어 각기 독립된 별종으로 확인되었다. M. lagowskii의 분포지역인 경포호집단은 유전적으로 뚜렷한 차이가 있고 형태적 특징으로 보아 M. percnurus로 추정된다. 각 종의 분화연대를 추정한 결과 이들은 선신세후기에서 홍종세 초기에 걸처 종분화가 되었고, 고 Amur 하 수계를 통하여 이주, 분포한 것으로 추측된다.

• 한국통신학회논문지
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• 제32권6A호
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• pp.565-572
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• 2007

3G Long Term Evolution (3G LTE)은 OFDMA와 MIMO기반 무선접속 기술을 이용해 다양한 모바일 멀티미디어 서비스를 제공하는 차세대 이동통신 시스템이다. 기존 WCDMA기반 시스템과 여러 면에서 차이가 있지만, 3G LTE는 Physical Resource Block (PRB)을 무선전송 자원으로 사용하고, 모든 서비스가 PS 도메인을 통해 이루어진다는 점에서 새로운 자원관리 방식의 개발을 필요로 한다. 본 논문은 Adaptive Partitioning 기반의 다운링크 호 수락제어 방식을 제안한다. 실시간과 비실시간 호를 구분하여 호 종류별로 최대 사용가능 자원량을 미리 지정하고, 한계 초과시 잉여자원량에 비례하여 확률적으로 호를 수락하는 방식이다. 이러한 adaptive 개념은 이미 다른 호 수락제어에서 사용되어 왔지만, PRB의 특징을 활용한 적용방식을 고안하고 PRB utilization과 payload ratio을 이용해 기지국 자원사용량을 측정하는 것은 본 논문의 특징이다. 시뮬레이션을 통해 다른 방식들과 성능 비교한 결과, 실시간 신규 호의 수락을 우선할 수 있었으며, 전체 시스템 성능 또한 우수한 것으로 확인되었다.

• Human Ecology Research
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• 제56권1호
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• pp.33-54
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• 2018

This study devised an instruction that applies the content factors of Family Life Planning to backward design by exploring the fundamental concepts of backward design and the structure of developing a systematic instruction. Furthermore, it was conducted to improve the developed instruction by examining its validity with the help of experts and to find the method of applying it to the curriculum. The lesson design of this study was as follows. 1) Making a unit outline, 2) Identifying the expected results (Shaping the objectives), 3) Deciding acceptable evidence (Planning evaluation), 4) Making a detailed blueprint for class tasks, 5) Planning learning experience, 6) Making a learning experience plan per time, 7) Checking the lesson design. Second, experts participated in this study for the internal validity test about the process of the systematic lesson development of Family Life Design based on a backward design. The results were shown to be valid because the average was 3.7 out of a perfect score 4 and the CVI of all was over 0.9. The result of the IRA was also score 1, meaning that most of the experts agreed on the results of the test. The details of the lesson design were clear at every stage and the tasks and the results of each stage were specific. This study included most of the necessary stages for a backward design.

• 한국가구학회지
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• 제23권4호
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• pp.467-478
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• 2012

Interurban railway is expanded by transportation that population can be centralism and cope efficiently in traffic jam by augmentation of vehicles in the city. Railroad chair departs in space of an existent simple rest and products that can raise human body standard and size by powerful engineering vicinity, quality of the material, psychological satisfaction etc. of users are developed steadily. Specially, study of space that can use various materials efficiently with bodily size government official because various of man and woman old and the young etc.. are using in occasion of the train is urgently required. Specially, railroad chair is a product that material and standard, structure, human body engineering, a finish etc. is studied variously. In the case of advanced nation, in case of design a chair operating time of railroad, is placed as all standards orderly and harmonious because is considered exercise dynamics etc.. and designs. The other side, in the case of our country, study expert of chair is short real and is depending on technological data of overseas railway vehicle. Chair for railroad must consider removal of short-range, long distance. That have to be consider to a lot of uncomfortable such as psychological satisfaction of user because the domestic Motor Companies are defining in fair development study and many researchers but the railroad chair company are not accumulated professional manpower and technological know-how. Railway vehicle can recognize that overseas visitors as well as native is important element as space that space is exposed internationally by product that Public personality which used cultural value is strong. Therefore, wish to plan valid spec relationship presentation of various design and specification, function etc.. and contribute to railroad chair development design process lists and analyzes van instances of railway vehicle chair of inside and outside of the country through this study.

• 대한의용생체공학회:의공학회지
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• 제29권3호
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• pp.198-204
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• 2008

Uroflowmetry is a non-invasive clinical test useful for screening benign prostatic hyperplasia(BPH) common in the aged men. The current standard way to obtain the urinary flow rate is to continuously acquire the urine weight signal proportional to volume over time. The present study proposed an alternative technique measuring pressure to overcome noise problems present in the standard weight measuring technique. Experiments were performed to simultaneously acquire both weight and pressure changes during urination of 9 normal men. Noise components were separated from volume signals converted from both weight and pressure signals based on the polynomial signal model. Signal-to-noise ratio was defined as the ratio of the energies between signal and noise components of the measured volume changes, which was 8.5 times larger in the pressure measuring technique, implying that cleaner signal could be obtained, more immune to noisy environments. When four important diagnostic parameters were estimated, excellent correlation coefficients higher than 0.99 were resulted with mean relative errors less than 5%. Therefore, the present pressure measurement seemed valid as an alternative technique for uroflowmetry.

• 한국정보과학회논문지:시스템및이론
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• 제37권5호
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• pp.272-284
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• 2010

플래시 메모리는 하드 디스크와 여러 면에서 다른데 특히 덮어쓰기가 되지 않는다는 것이 가장 큰 차이점이다. 그로 인해 대부분의 플래시 메모리 파일 시스템들은 파일을 수정할 때 not-in-place 수정 기법을 사용하고 있다. 그 과정에서 가끔 플래시 메모리 파일 시스템들은 가용 공간의 확보를 위해 무효 페이지들이 많은 블록들의 유효 페이지들을 다른 블록으로 옮기고 블록들을 쓸 수 있는 빈 페이지로 만들어 주는 작업인 블록 클리닝 작업을 수행한다. 블록 클리닝 작업은 플래시 메모리의 성능을 직접적으로 좌우하는 요소이다. 그래서 이 논문은 유효 페이지와 무효 페이지를 동시에 가진 블록의 수를 최소화하여 블록 클리닝 비용을 줄일 수 있는 효율적인 페이지 할당 기법을 제안한다. 그리고 실험 결과는 원래의 YAFFS에 비해 블록 클리닝 비용이 확연하게 줄어들었음을 보여 준다.