• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.270-278
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• 2009

Most of previous studies on civil servants' stress factors and job satisfaction have been focused on low job satisfaction caused by stress from role relations and human relations. In case of fire officers, however, their stress is expected to be influenced by their unique job characteristics such as risk, urgency, stand-by, and shift. Thus, this study divided fire officers'stress factors into job-related factors (risk, urgency, stand-by, alternation) and role-related factors (role conflict, role ambiguity, role overload), and empirically analyzed how these factors affect their job satisfaction. According to the results of this study, fire officers' job characteristics and their roles in the organization had a significant effect on their job satisfaction. Particularly, among the job-related factors, urgency and stand-by had a positive effect on job satisfaction, and among role-related factors, role conflict and role overload had a negative effect on job satisfaction. In addition, fire officers' stress and job satisfaction were significantly different according to their job (fire fighting, rescue and first aid, fire administration, others), and according to their workplace (fire fighting headquarters, fire station, 119 safety center).

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2007.05a
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• pp.331-335
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• 2007

본 연구에서는 장기간의 현장관측 수온, 염분자료를 분석하여 동중국해 북부해역에서 계절별 수온, 염분의 변동 특성을 조사하였다. 표층의 경우 춘계 수온상승에는 공간적인 차이가 있다. 또한 서부해역($125^{\circ}E$ 이서)에서는 32 psu 이하의 저염 분포가 나타나고 제주 남서해역에서 33psu 이하의 저염수가 춘계부터 제주 주변해역으로 확장한다. 하계 표층염분은 $28.0{\sim}32.4$ psu로 연중 최저값은 보이며, 전해역 표층 염분이 33psu 이하로 저염의 양자강 희석수가 하계에 동중국해 북부해역 표층 전체에 영향을 미치고 있다. 추계의 표층수온과 염분은 동고서저형의 수평분포를 나타낸다. 수온 하강은 서부해역인 대륙 연안수역이 동부의 대마난류수역에 비해 크고, 서부해역에서 33psu 이하의 설상형 저염분포가 이시기에 남동쪽으로 관입되는 형태로 나타나 동계의 남북방향의 염분전선과 이어지게 된다. 연직해황의 경우 동계 수온과 염분은 활발한 대륙작용에 의해 전수층에서 균일한 분포를 나타내며, 대륙연안수역에서는 저온, 저염($12^{\circ}C$, 33psu 이하)의 분포를, 대마난류수역에서는 고온, 고염($16^{\circ}C$, 34.4psu 이상)분포의 지역적인 특성으로 구별된다. 춘계에는 수온약층이 형성되며, 저층에는 동계에 형성되어 대륙연안수와 외양수 사이에 고립된 $13^{\circ}C$ 이하의 냉수괴가 분포한다. 염분은 표층 저염화가 시작된다. 하계에는 양자강 유출수의 영향으로 전해역 표층에서는 30psu 이하로 전해역에서 저염화 양상이 나타나며, 표층에서 30m 층까지 매우 강한 염분약층이 형성된다. 추계 수온 엽문은 균일한 연직수온분포가 나타나며, 동부해역에서는 수심 $75{\sim}100m$사이에서 수온, 염분약층이 형성된다. 동중국해의 수괴는 뚜렷한 계절 변동을 보이며, 대마난류수역인 동부해역에서는 수괴 계절변동의 요인으로 계절 수온변동이 지배적이고, 수온변동은 춘계와 하계 사이에 가장 크다. 중앙부와 대륙연안역인 서부해역에서는 수괴 계절변동에 수온외에 염분 변화가 주요한 요인으로 작용하며, 염분은 하계와 추계 사이에 가장 변동이 크게 나타난다. 즉, 동중국해의 수괴변동에는 변동요인에 따른 공간적인 차이가 있으며, 수괴변화 특성으로 동중국해는 수온변화가 수괴변동에 직접요인이 되는 동부 대마난류수역과 염분변화가 수괴변동의 직접요인인 서부의 대륙연안수역으로 구분된다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1618-1623
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• 2019

In this paper, inductive couplers realizing broadband powerline communication (PLC) are fabricated using Fe-based nanocrystalline alloy and their performance is analyzed. As a result of the field tests using the distribution automation system (DAS), the couplers achieve comparatively excellent data communication in the principal frequency band of broadband PLC although there is a difference in communication rate depending on the presence or absence of a branch. In addition, it has been confirmed that the communication speed is maintained for a real-time transmission even in a high current environment although there is a difference in the transmission rate depending on the distance. Hence, it is considered that the inductive couplers can be used as a core device to realize the intelligent power network by exploiting them for the monitoring and remote controlling of the power plant equipments for the DAS located in the inaccessible areas.

• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.195-195
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• 2022

도림천의 최상류인 관악산 유역에 서울대학교 관악캠퍼스가 건설되었다. 이로 인해 물순환은 기존의 자연 상태에서 점점 변해 왔는데, 이는 하류 도림천의 홍수 및 수질 오염의 피해를 증가시켰다. 도시화된 서울대학교 관악캠퍼스의 물순환 회복은 하류 홍수피해 방지와 지속 가능한 친환경 캠퍼스를 위해 중요하나, 이에 관한 연구는 미흡한 실정이다. 따라서 본 연구에서는 SWMM(Storm Wastewater Management Model)을 활용하여 캠퍼스 내 물순환 현황을 시간과 공간에 대해 정량적으로 파악하고, 물순환 회복을 위해 지속 가능한 효율적인 시스템을 구현하고자 한다. 먼저 유역 현황 조사와 함께 SWMM 구축에 필요한 수문·기상학적 변수와 물리적 매개변수를 확립하였다. 수문·기상학적 변수로는 기상관측장비 ATMOS-41의 설치와 기상청 자료로부터 수집하였으며, 물리적 매개변수는 환경부의 자료를 활용하였다. 그 후, 서울대-도림천 배수분구에 대해 SWMM을 적용하여 월별로 유출량, 침투량, 그리고 증발산량을 모의하였다. 시간에 따른 물순환 분석의 경우 강수량 자료와 불투수율의 변화 정도에 따라 월별 물수지 비율을 파악하고, 공간에 따른 물순환 분석의 경우 동일한 기간에 대해 분할한 16개의 소유역 별 유출량과 유역의 평균 유출량을 비교하여 분석하였다. 대상 유역의 월별 물수지 비율을 모의하는데 효율성을 높이고자 배수 구역 및 관망을 세밀하게 나눈 경우와 그렇지 않은 경우에 대해 분석하였다. 그 결과, 시간에 따른 연평균 물수지 비율의 차이는 2020년 모의 결과와 최근 5년 평균(2015~2019년) 모의 결과 비교 시 각 물수지 항목별로 0.47~2.34%의 차이를 보였다. 공간적으로는 16개 소유역 중 저류시설을 포함한 9개 소유역의 표면 유출량이 유역의 평균 유출량보다 많게 모의 되었다. 또한, 유역을 구성할 때보다 관망을 구성할 때 높은 정확성이 요구됨을 알 수 있었다. 본 연구는 ATMOS-41을 통한 지속적인 수문·기상학적 요소의 모니터링과 SWMM 모델 구축을 통해 앞으로도 변경사항을 추가함으로써 친환경 캠퍼스로의 전환에 이바지할 것으로 기대한다.

• Phonetics and Speech Sciences
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• v.14 no.2
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• pp.1-10
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• 2022

A wh-phrase positioned in an embedded clause can be interpreted as having a matrix scope if the sentence is produced with proper prosodic structures such as the wh-intonation. In a previous experiment, a sentence with a wh-phrase in an embedded clause was given to 40 speakers of Gyeongsang Korean. A script containing the sentence was provided to induce a matrix scope interpretation for the wh-phrase. These 40 utterances were prepared as stimuli for a perception test to verify whether the wh-phrases in the stimuli were perceived as having matrix scopes. Each utterance was played thrice to 24 subjects. The results showed that more than half of the 72 responses indicated a preference for an embedded scope rather than a matrix scope in 20 of the utterances. A multiple linear regression analysis showed that the matrix scope responses were best predicted by the magnitude of the pitch prominence in a prosodic word consisting of an embedded verb and a complementizer. The pitch prominence was calculated by subtracting the fundamental frequency (F0) at the right edge of the prosodic word from the peak F0 in the same prosodic word. The smaller the magnitude, the more matrix responses there were. These results suggest that the categorical perception of wh-scopes is based on the magnitude of pitch prominence.

• Phonetics and Speech Sciences
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• v.15 no.2
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• pp.1-11
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• 2023

This study investigated the response time and patterns of categorical perception of the wh-scope of an embedded clause with the non-bridge verb, "gung-geum hada 'wonder'," in the matrix verb phrase in Gyeongsang Korean. Using the same procedure as Yun (2022), 72 responses and response times for each stimulus were collected from 24 participants over the course of three trials. The stimuli were recorded readings of 40 speakers (20 male, 20 female). Context was provided to induce a matrix scope interpretation of the embedded wh-phrase in the target sentence. We sorted the 40 stimuli according to the number of matrix scope responses each received, and charted the response times for each stimulus. Although there was considerable overlap for the different types of wh-scope interpretations, there was a clear difference in categorical perception between the matrix and embedded scopes. The 24 participants also differed in their categorical perceptions. The results suggested that response time and wh-scope interpretation were not directly related and that two main weighted factors affected wh-scope interpretation: morpho-syntactic constraints and prosodic structural integrity. The weighting of each of these factors was inversely correlated and varied among subjects.

• Phonetics and Speech Sciences
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• v.16 no.2
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• pp.37-47
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• 2024

This study was conducted on 27 male students majoring in or preparing for popular music vocals to determine whether they were aware of their voice classification and vocal range. Additionally, differences in the fundamental frequency and average speaking fundamental frequency were compared among the voice classifications. Moreover, considering that they may differ in their ability to produce high frequencies depending on the vowel, differences in voice ranges among the cardinal vowels, /a/, /i/, and /u/, were examined, and differences in voice ranges between vowels were compared by voice classification. The results showed that more than half of the male students majoring in or preparing for popular music vocals were not accurately aware of their voice types. In addition, statistically significant differences were found in the maximum fundamental frequency and frequency range among vowels, indicating differences in the voice range that can be produced depending on the vowel type. In particular, the voice range decreased in the following order: /a/>/u/>/i/. This suggests that while the vowel /a/ is easier to articulate in the high register compared to other vowels, vowels /u/ and /i/ as high vowels involve narrowing of the oral cavity due to the raised position of the tongue, accompanied by raising of the larynx, resulting in a decrease in voice range and difficulty in vocalizing in the high register.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.330-342
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• 1998

Benthic environmental parameters were analysed at 40 stations during the period from April 1995 to February 1996. such as water temperature, salinity, and dissolved oxygen (DO)-concentration in the surface and bottom water layers, grain size, chemical oxygen demand (COD), ignition loss, particulate organic carbon (POC) in the sediment of Youngsan River estuary. The water temperature ranged from 4.1 to $29.8^{\circ}C$ in the surface and 4.0 to $20.7^{\circ}C$ in the bottom layers. Salinity ranged from 15.1 to $33.6\%_{\circ}$ in the surface and 31.5 to $33.2\%_{\circ}$ in the bottom layer. The salinity in the outer pan of the study area was higher than that of inner area from autumn to spring, whereas they remained lower in summer. Dissolved oxygen concentration ranged from 5,1 to 11.2 $mg/\ell$ in the surface, and 0.79 to 10,2 $mg/{\ell}$ in the bottom layers. Hypoxic condition ($\le2.0mg/\ell$) was developed in the bottom water layer from Youngsan dike to Mokpo Harhour in summer due to the summer stratification. The surface sediment type was silty clay with a mean grain size of $9.12{\pm}0.45\phi$. The range of COD was from 6.15 to $15.49mgO_2/g$ with a mean of $10.59{\pm}12.64mgO_2/g$. The COD in the inner stations was relatively higher than that of outer stations, and decreased toward the outer part of the study area. Ignition loss (IL) ranged from 3.35 to $15.45\%$ with a mean of $5.96{\pm}1.91\%$. Principal component analysis was carried out from the following five environmental parameters: water temperature, dissolved oxygen in the bottom layer and mean grain size, clay content and COD in the sediment. The forty stations in the study area were classified into three stational groups. Group I was located in the inner part of the estuary characterised by relatively low surface salinity and bottom water temperature, fine sedimemt texture, high organic matter and low dissolved oxygen concentration during the summer. Meanwhile, Group III showing relatively high bottom salinity and water temperature was located in the outer part of the estuary characterising coarse sediment and low organic content in sediment. Group II was between Group I and Group III. The division of the areal groups had high correlations to the DO in the bottom layer and clay content in the sediment.

• Korean Journal of Ichthyology
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• v.30 no.4
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• pp.224-231
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• 2018

Dietary niches can support the coexistence of sympatric species in marine ecosystems, which can lead to the presence of greater abundances of those species. Stomach contents of silver croaker (Pennahia argentata) and Japanese sillago (Sillago japonica) inhabiting the Nakdong River estuary, Korea were analyzed to determine diet compositions and the presence of any size-related and inter-specific feeding relationships. These species were bottom-feeding predators that consumed mainly benthic crustaceans and mollusks, but polychaetes were also important in the S. japonica diets. Non-metric multidimensional scaling (nMDS) ordination and multivariate analyses based on weight contributions of the different prey taxa to stomach contents revealed significant inter-specific dietary differences. Size-related change was also significant for P. argentata diets, but not for S. japonica. Canonical analysis of principal coordinate (CAP) ordination plot further demonstrated that differences in the type and range of prey ingested by the two species contributed such an inter-specific difference in the diet compositions. The results from this study provide clear evidence of niche segregation between co-occurring P. argentata and S. japonica in the Nakdong River estuary, which would reduce the likelihood of inter-specific competition for food resources.

• Journal of the korean academy of Pediatric Dentistry
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• v.38 no.2
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• pp.161-169
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• 2011

Longitudinal serial cephalometric films in the every second year from fifty girls were used for the analysis of growth pattern of maxillary alveolar bone (MAE). Six parameters regarding MAB height were measured and were compared with stature and chronological age. Descriptive analysis. correlation coefficient test and linear regression analysis were done for the statistical analyses. 1. The height of MAE increased until 14 years although growth velocity was gradually decreased. which was different with stature growth pattern. 2. The correlation coefficients between chronological age and MAB height were high and had no statistical differences with those of stature and MAB height. In addition. the correlation coefficients between chronological age groups within each parameter of MAB were very high. 3. The growth amount of MAB could be predicted using linear regression analysis on the basis of chronological age data. The growth pattern between MAE and statue was quite different because of the growth pattern difference between skeletal and neuronal system. Therefore. growth pattern of Korean MAB must be considered in dental treatment of youth. Also. close relationship between chronological age and MAB height would be useful when clinicians want to predict growth amount of MAE for the dental implant treatment.