• 한국산업정보학회논문지
• /
• 제27권5호
• /
• pp.25-36
• /
• 2022

본 논문은 단일 반송파 변조를 위한 공간 주파수 블록 코드에서의 랜덤 부호 반전 기술을 제안한다. 종래의 시공간 그리고 공간 주파수 블록 코드는 전파 환경이 공개되어 있으므로 심각한 전파 탈취 문제를 극복해야 한다. 이러한 전파 공개 문제를 피하기 위해, 시공간 블록 코드를 위한 랜덤 코드 데이터 보호 방법이 제안되어 있지만, 이 알고리즘은 직교 주파수 분할 다중화 블록별로 채널 결합을 바꿀 수 있는데, 이와 같은 종류의 느린 스위칭은 근처의 수신기들이 전송된 데이터를 검출할 확률을 증가시킨다. 이 논문은 데이터 심볼 기반의 빠른 스위칭 알고리즘 즉, 단일 반송파 변조를 위한 공간 주파수 블록 코드에서의 랜덤 부호 반전 기술을 제안한다. 모의실험 결과는 제안하는 알고리즘이 랜덤 부호 반전 타이밍 시퀀스를 모르는 수신기의 성능과 비교하여 우수한 성능을 보유하고 있다는 것을 나타내었다.

• 한국측량학회지
• /
• 제39권6호
• /
• pp.381-392
• /
• 2021

본 연구에서는 UAV (Unmanned Aerial Vehicle)로 촬영한 이미지를 활용하여 수치지도 지형지물 표준 코드에서 정의하고 있는 건물 8종에 대하여 딥러닝 기반의 객체 탐지 분석을 수행하였다. UAV로 촬영한 이미지 509매에 대하여 이미지 라벨링을 하였고 YOLO (You Only Look Once) v5 모델을 적용하여 학습 및 추론을 진행하였다. 실험 및 분석은 오픈소스 기반의 분석 플랫폼과 알고리즘을 적용하여 데이터를 분석하였으며 분석결과 88%~98%의 예측 확률로 건물 객체를 탐지하였다. 또한 학습데이터의 구축 및 반복 학습의 과정에서 건물 객체 탐지의 높은 정확도를 위해 필요한 학습 방식 및 모델 구축방식을 분석하였고, 학습한 모델을 다른 영상자료에 적용하는 방안을 모색하였다. 본 연구를 통해 고효율 심층 신경망과 공간정보데이터가 융합하는 모델을 제안하며 공간정보데이터와 딥러닝 기술의 융합은 향후 공간정보데이터 구축의 효율성, 분석 및 예측의 정확도 향상에 많은 도움을 제공할 것이다.

• Asian Journal for Public Opinion Research
• /
• 제9권2호
• /
• pp.188-211
• /
• 2021

Decreasing response rates to traditional survey methods, like face-to-face and telephone interviews, have led survey practitioners around the world to seek new ways of conducting surveys in recent years." The COVID-19 pandemic exacerbated this problem because it made conducting face-to-face interviews even more difficult than before. For example, it made conducting face-to-face surveys infeasible in 2020 in South Korea, and so the Korean Academic Multimode Open Survey (KAMOS) was unable to conduct a planned face-to-face survey to recruit new panel members. The entire 8,514-member panel, established via two-stage probability-based sampling from 2016 to 2019, was invited to take three online/telephone surveys in 2020. Of these panel members, 1,352 responded to at least one survey in 2020. To test to what extent the panel remained representative of the adult South Korean population, we compared the two groups of panel members: those who responded to at least one survey in 2020 and those who did not. After weighting both groups on the basis of age, sex, and geographical area, we analyzed their responses to some of the questions that were asked during multiple rounds of the face-to-face panel-recruiting interviews. Using Cohen's d for survey items that could be analyzed numerically and Cramér's V for categorical items, we were able to conclude that the respondents to the 2020 surveys were equivalent to the non-respondents in terms of both demographics and in the answers they originally gave to substantive questions on a variety of topics related to social science or public opinion research, including questions about quality of life, societal issue, and politics (Cohen's d items <0.2, 95% CI; Cramér's V items <0.1, 95% CI). This analysis may provide a model for others who wish to test the continued representativeness of their panel or who would like to use a different survey mode or change some other aspect of their methodology and test whether it is equivalent to their former methodology. Our success in building a panel that retained its representativeness may be useful to those in other countries where face-to-face surveys had previously been the norm but are becoming increasingly difficult to conduct.

• 한국전문물리치료학회지
• /
• 제30권3호
• /
• pp.230-236
• /
• 2023

Background: The globalization of the healthcare industry and the increasing demand for skilled professionals in the global healthcare industry have opened up opportunities for specialized biotech healthcare professionals to seek overseas employment and career advancement. Objects: This study aimed to develop educational content essential for the overseas employment of digital bio-health professionals. Methods: A survey was conducted among 196 participants. Google Forms (Google) were utilized to create and administer the survey, employing purposive sampling, a non-probability sampling method. Data analysis was performed using IBM SPSS 25.0 (IBM Co.), including Cronbach's α and independent sample t-tests to assess significant differences. Results: About half of college students are interested in overseas employment and international careers, while the other half had not. The most common reason for wanting to work or go overseas was "foreign experience will be useful for future activities in Korea." Students who had experience taking courses from the Bio-health Convergence Open Sharing University preferred overseas programs more than those who did not have that experience. In terms of the degree of desire for overseas education courses provided by universities, contents related to human health were the highest, followed by bio-health big data. Conclusion: Many students wanted to work and go overseas if there is sufficient support from the university. The findings in this study suggest that universities are necessary to play an important role in supporting students' aspirations to work or go overseas by providing language education, education and training programs, information on overseas jobs, and mentoring programs.

• 국제학술발표논문집
• /
• The 5th International Conference on Construction Engineering and Project Management
• /
• pp.338-343
• /
• 2013

Integrated Project Delivery (IPD) as a delivery method fully capitalizes on an integrated project team that takes advantage of the knowledge of all team members to maximize project outcomes. IPD is currently the highest form of collaboration available because all three core project stakeholders, owner, designer and contractor, are aligned to the same purpose. Compared with traditional project delivery approaches such as Design-Bid-Build (DBB), Design-Build (DB), and CM at-Risk, IPD is distinguished in that it eliminates the adversarial nature of the business by encouraging transparency, open communication, honesty and collaboration among all project stakeholders. The team appropriately shares the project risk and reward. Sharing reward is easy, while it is hard to fairly share a failure. So the compensation structure and the contingency in IPD are very different from those in traditional delivery methods and they are expected to encourage motivation, inspiration and creativity of all project stakeholders to achieve project success. This paper investigates the compensation structure in IPD and provides a method to determine the proper level of contingency allocation to reduce the risk of cost overrun. It also proposes a method in which contingency could be used as a functional monetary incentive when established to produce the desired level of collaboration in IPD. Based on the compensation structure scenario discovered, a probabilistic contingency calculation model was created by evaluating the random nature of changes and various risk drivers. The model can be used by the IPD team to forecast the probability of the cost overrun and equip the IPD team with confidence to really enjoy the benefits of collaborative team work.

• Steel and Composite Structures
• /
• 제50권3호
• /
• pp.249-263
• /
• 2024

This article presents a comparative analysis of seismic behavior in steel-beam reinforced concrete column (RCS) frames versus steel and reinforced concrete frames. The study evaluates the seismic response and collapse behavior of RCS frames of varying heights through nonlinear modeling. RCS, steel, and reinforced concrete special moment frames are considered in three height categories: 5, 10, and 20 stories. Two-dimensional frames are extracted from the three-dimensional structures, and nonlinear static analyses are conducted in the OpenSEES software to evaluate seismic response in post-yield regions. Incremental dynamic analysis is then performed on models, and collapse conditions are compared using fragility curves. Research findings indicate that the seismic intensity index in steel frames is 1.35 times greater than in RCS frames and 1.14 times greater than in reinforced concrete frames. As the number of stories increases, RCS frames exhibit more favorable collapse behavior compared to reinforced concrete frames. RCS frames demonstrate stable behavior and maintain capacity at high displacement levels, with uniform drift curves and lower damage levels compared to steel and reinforced concrete frames. Steel frames show superior strength and ductility, particularly in taller structures. RCS frames outperform reinforced concrete frames, displaying improved collapse behavior and higher capacity. Incremental Dynamic Analysis results confirm satisfactory collapse capacity for RCS frames. Steel frames collapse at higher intensity levels but perform better overall. RCS frames have a higher collapse capacity than reinforced concrete frames. Fragility curves show a lower likelihood of collapse for steel structures, while RCS frames perform better with an increase in the number of stories.

• 한국환경보건학회지
• /
• 제42권3호
• /
• pp.147-159
• /
• 2016

In South Korea, many cases of humidifier disinfectant-associated lung injury (HDLI) have been reported among people who used humidifier products containing humidifier disinfectant (HD). The objective of this study is to characterize exposure to HD among a total of 221 HDLI patients who used HD. Information and data on the HDs used were collected through a structured questionnaire and home environmental investigations. The conditions of these 221 HDLI patients were clinically confirmed to be caused by the use of HD. Children aged under 5 years old made up the highest proportion of HDLI cases (n=125, 56.6 %), followed by pregnant women (n=35, 15.8%). Forty-three percent (n=95) of the victims died. There were three cases of fetuses and 35 pregnant women among the victims. The number of HDLI patients who used only the Oxy Saksak brand of HD was found to be 85 (38.5%), followed by the HD brands Cefu (n=24, 10.9%), Lottemart Wiselect (n=9, 4.1%) and Aekyung (n=3). Patients who exclusively used HD brands containing polyhexamethylene guanidine phosphate (PHMG) (n=13, 55.7%) as an active ingredient made up the largest share, followed by those who exclusively used HD containing only oligo(2-(2-ethoxy) ethoxyethyl guanidinium (PGH) (n=24, 10.9%) and by those who only used a mixture of chloromethylisothiazolinone (CMIT) and methylisothiazolinone (MIT) (n=3, 1.4%). HD products containing PHMG were found to be the most commonly used among the confirmed HDLI patients. Three exposed fetuses who never used HD after birth developed lung injuries, indicating a probability of exposure to HD during gestation. All HDLI patients responded that they used HD while sleeping and for longer than 10 hours per day. In conclusion, the development of HDLI was clinically found to be associated with the use of several HD products containing PHMG, PGH and CMIT/MIT.

• 한국산림과학회지
• /
• 제66권1호
• /
• pp.109-117
• /
• 1984

잡종채종원상(雜種採種園上)의 리기다소나무 49가계(家系)로부터 종자(種字)를 채취하여 종자(種字)의 배유(胚乳) 및 배(胚)에 대한 Aspartate aminotransferase(AAT), Glutamate dehydrogenase(GDH) 및 Leucine aminopeptidase(LAP)등의 Allozyme 변이(變異)를 조사하여 다음과 같은 결과를 얻었다. 이들 세 가지 Allozyme system에서 AAT에 5개, GDH에 1개 및 LAP에 2개, 모두 8개의 유전자좌(遺傳子座)(Locus)가 발견되었으며 GDH를 제외한 모든 유전자좌에서 Allozyme Polymorpshism을 발견하였다. 각 유전자좌에 있어서 평균 대입유전자(對立遺傳子) 수(數)는 종자모수집단(種子母樹集團)에서 2.33개, 차대집단(次代集團)에서 2.67개였다. 평균이형접합성(平均異型接合性) 종자모수집단이 0.235, 차대집단(次代集團)이 0.238이었고 유전자의 유전적(遺傳的) 다양성(多樣性)은 종자모수집단이 5.409, 차대집단(次代集團)이 5.569로서 같은 수종의 다른 집단 또는 다른 침엽수 수종에 비하여 비교적 낮은 값을 나타냈다. Allozyme분석에 의하여 잡종채종원의 리기다소나무에 있어서 일대잡종(一代雜種) 종자(種子) 발생율(發生率)을 추정해 본 결과 일대잡종 종자의 발생빈도는 0.77%로서 묘포에서 조사한 일대잡종묘의 발생율 0.73%와 거의 일치하였다. 잡종채종원상의 종자모수 리기다소나무 및 이대 차대들 Allozyme변이에 있어서 Wahlund 효과(效果), 비교적 높은 수준의 자가수정(自家受精) 및 Non-random mating 등의 가능성이 발견되어 이들에 대한 Allozyme 변이 연구에 깊은 주의가 필요하다.

• 미생물학회지
• /
• 제40권2호
• /
• pp.81-86
• /
• 2004

Streptomyces coelicolor의 전 유전체 청보를 분석한 결과(7), 유전자 ID1103135가 코드 하는 open reading frame SCO7697이 phytase[myo-inositol hexakisphosphate phosphohydrolase상동성 (3-6,8,23)]에 유의하게 유사한 것으로 판단되었다. S. coelicolor A3(2)M의 염색체 DNA를 주형으로 PCR 방법으로 SCO7697 전체를 포함하는 DNA 단편을 클로닝하였다. 두 가지의 서로 다른 길이를 갖는 클로닝 된 ID1103135 DNA 단편을 E. coli 발현용 벡터pET728a(+)에 삽입하여,두 종의 재조합 벡터 pET28-SP와 pET28-LP를 얻었다. pET28-SP 와 pET28-LP를 각각 E. coli BL2l에 도입하여, IPTG로 발현 유도된 단백질을 SDS-polyacrylamide 전기영동으로 확인한 결과, 발현은 성공적으로 이루어 졌으나 대부분불용체를 형성하고 분자량은 예상보다 약간 큰 것으로 나타났다. 불용체 형성은 단백질의 불활성화를 수반 함으로서, 배양 온도를 $37^{\circ}C$에서 $30^{\circ}C$로 변화시켜 배양하는 방법으로 발현된 단백질을 가용화 시켰다. 발현된 단백질을 추출하여 조추출물 또는 정제한 상태로 phytase활성을 측청하였으나 효소활성은 관찰할 수 없었다. 대장균 시스템에서의 발현이 효소 활성의 소실을 초래했을 가능성이 있으므로, ID1103135 유전자를 자신의 promoter를 함유하도록 PCR 클로닝하여, E. coli - Streptomyces의 shuttle vector인 pWHM3에 삽입하고, 이를 방선균 호스트인 S. lividans에 도입하였다. 형질 전환체의 세포조추출액 및 세포배양액의 phytase 활성을 측청하였으나, 역시 활성을 확인할수 없었다. 이와 같은 결과는 SCO7697이 아주 높은 확률(E value; $6e^{-89}$)로 phytase일 것으로 annotation 되었으나, 실제는 이와는 다른 기능을 함유하고 있음을 시사하고 있다.

• 한국가금학회지
• /
• 제22권3호
• /
• pp.133-144
• /
• 1995

One metabolism trial(Experiment I) and another respiration trial(Experiment II) were conducted to investigate the effects of dietary fiber supplementation(20% wheat bran) on the water balance, blood acid-base balance, body temperature, and metabolic rate of heat-stressed adult roosters. In Experiment I, twenty 20-wk-old SCWL roosters(BW 1.6 kg) were randomly alloted to 4 treatments with 5 birds per treatment and one per replicate. The 4 treatments were consisted of two temperature(21~22˚C vs. 34~35˚C) and two dietary fiber treatment(0% and 20% wheat bran), making Experiment I a 2x2 factorial. After 4 d of preliminary period, birds we subjected to 3-d collection period. Sixteen 20-wk-old SCWL roosters(BW 1.6 kg) were employed Experiment H, with two temperature(21~22˚C vs. 34~35˚C) and two wheat bran levels(0% and 20%). Brids were housed in individual metabolism cages under normal temperature(21~22˚C), at fed one of the experimental diet. After 4 d of preliminary period, a respiration trial with open-circuit gravimetric respiratory apparatus was carried out for each bird for 6 h, one by one, normal(20~21˚C) and hot(34~35˚C) temperatures. The ANOVA test and comparisons among treatment means were done at 5% probability level for both experiments. Results obtained from Experiment I and, II were summarized as follows, 1.The amounts of DM intake and excretion were significantly(P<.05) decreased by heat stress. The DM intake was not affected by the addition of 20% wheat bran, however, the amount of DM excretion was significantly increased by the high fiber diet. Thus, the DM metabolizability decreased significantly by the addition of 20% wheat bran. 2. The heat-stressed roosters increased the water intake and excreta moisture content significantly. Although not significant, the water intake tended to increase in roosters fed the 20% wheat bran diet. 3. The amounts of total water input and evaporative water loss were increased significantly by heat stress, and the addition of 20% wheat bran did not exert any influence on the total water input and evaporative water loss. However, roosters fed the 20% wheat bran diet increased the excreta water output significantly. 4. Neither the heat stress nor the dietary fiber did affect the blood pH, pCO2, and HCO$_3$- significantly. 5. The body temperature increased significantly by the heat stress. However, the high fiber deit failed to decrease the body temperature. 6. The heat-stressed roosters decreased the 02 consumption and C0$_2$ production, and increased the evaporative water loss significantly. However, the high fiber diet did not exert any infulence in this regard. It appears that the beneficial effect, if any, of high fibrous diet during heat stress episode may be due to the increased heat loss through the enhanced excreta water.