• Title/Summary/Keyword: Mid-frequency

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Acoustic Estimate of the Krill (Euphausia superba) Density between South Shetland Islands and South Orkney Islands, Antarctica, During 2002/2003 Austral Summer (음향 조사에 의한 2002/2003 하계 시기의 남극 남쉐틀랜드 군도와 남오크니섬 사이의 크릴 밀도)

  • Kang, Don-Hyung;Shin, Hyoung-Chul;Lee, Yoon-Ho;Kim, Yong-Sin;Kim, Su-Am
    • Ocean and Polar Research
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    • v.27 no.1
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    • pp.75-86
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    • 2005
  • Acoustic survey for density and biomass estimate of Antarctic krill, Euphausia superba, was conducted in the large area between South Shetland Islands and South Orkney Islands, during November 30-December 30, 2002. Considering oceanographic and geographic properties, the study area was divided into six sub-regions. Acoustic system and frequency used in the survey were quantitative echo sounder (Simrad Ek 500) and 38, 120-kHz split beam transducers. In order to discriminate krill aggregations in all acoustic signal, difference of mean volume backscattering strength $({\Delta}MVBS)$ method of the two frequencies was introduced. Averaged krill density for the overall surveyed area was $23.5g/m^2$, and spatially averaged estimates of krill density were $44.9g/m^2$ (north of the South Shetland Islands), $30.3g/m^2$ (Bransfield Strait), $11.3g/m^2$ (near the Elephant Island), $13.6g/m^2$ (north of the Elephant Island), $18.1g/m^2$(between Elephant Island and South Orkney Islands) and $21.7g/m^2$(northwest of the South Orkney Islands) at each sub-area. In the two sub-regions with surveyed area, estimated krill biomass in the north of the Elephant Island was 0.315 million tones with a CV of 18.35% $(6,766mile^2)$, and between Elephant Island and South Orkey Islands was 1.26 million tones with a CV of 9.45% $(20,299mile^2)$. As a whole, the krill density in the early summer season was low level, comparing with that of January-February. This suggested that major krill swarms in the around South Shetland Islands were reached in the mid-summer seasons from western part of the Antarctic Peninsula, and the low krill density also affects the density variation of the krill between Elephant Island and South Orkney Islands.

Transfer Impedence of Trip Chain with a Railway Mode Embedded - Using Seoul Metroplitan Transportation Card Data - (철도수단이 내재된 통행사슬의 환승저항 추정방안 - 수도권 교통카드자료를 활용하여 -)

  • Lee, Mee young;Sohn, Jhieon
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.6
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    • pp.1083-1091
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    • 2016
  • This research uses public transportation card data to analyze the inter-regional transfer times, transfer frequencies, and transfer resistance that passengers experience during transit amongst the metropolitan public transportation modes. Currently, mode transfers between bus and rail are recorded up to five times during one transit movement by Trip Chain, facilitating greater comprehension of intermodal movements. However, lack of information on what arises during these transfers poses a problem in that it leads to an underestimation of transfer resistances on the Trip Chain. As such, a path choice model that reflects passenger movements during transit activities is created, which attains explanatory power on transfer resistance through its inclusion of transfer times and frequencies. The methodology adopted in this research is to first conceptualize the idea of metropolitan public transportation transfer, and in the case that mode transfers include the city-rail, to newly conceptualize the idea of transfer resistance using transportation card data. Also, the city-rail path choice model within the Trip Chain is constructed, with transfer time and frequency used to reevaluate transfer resistance. Further, in order to align bus and city-rail station administrative level small-zone coordinates to state and regional level mid-zone coordinates, the big node methdod is utilized. Finally, case studies on trip chains using at least one transfer onto the city-rail is used to determine the validity of the results obtained.

Dietary Patterns and Prevalence Odds Ratio in Middle-aged Adults of Rural and Mid-size City in Korean Genome Epidemiology Study (40대 이상 농촌 및 중소도시 성인의 식품섭취 패턴 (Pattern)과 질환별 유병위험도 - 한국인유전체역학조사사업 일부 대상자에 대해 -)

  • Ahn, Youn-Jhin;Park, Yun-Ju;Park, Seon-Joo;Min, Hae-Sook;Kwak, Hye-Kyoung;Oh, Kyung-Soo;Park, Chan
    • Journal of Nutrition and Health
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    • v.40 no.3
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    • pp.259-269
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    • 2007
  • Recently, dietary pattern analysis was emerged as an approach to examine the relationships between diet and risk of chronic diseases. This study was to identify groups with population who report similar dietary pattern in Korean genome epidemiology study (KoGES) and association with several chronic diseases. The cohort participants living in Ansung and Ansan (Gyeonggi province) were totally 10,038. Among those, 6,873 subjects with no missing values in food frequency questionnaire were included in this analysis. After combining 103 food items into 17 food groups, 4 dietary factors were obtained by factor analysis based on their weights. Factor 1 showed high factor loadings in vegetables, mushrooms, meats, fish, beverages, and oriental-cereals. Factor 2 had high factor loadings in vegetables, fruits, fish, and factor 3 had high factor loadings in cereal-oriental, cerial-western and snacks. Factor 4 showed positive high factor loadings in rice and Kimchi and negative factor loadings in mushrooms and milk and dairy products. Using factor scores of four factors, subjects were classified into 3 clusters by K-means clustering. We named those 'Rice and Kimchi eating' group, 'Contented eating' group, and 'Healthy and light eating' group depending on their eating characteristics. 'Rice and Kimchi eating' group showed high prevalence in men, farmers and 60s. 'Contented eating' group and 'Healthy and light eating' group had high prevalence in women, people living in urban area (Ansan Citizen), with high-school education and above, and a monthly income of one million won and more. 'Contented eating' group appeared lower distribution proportion in the sixties and 'Healthy and light eating' group does higher in the fifties. 'Contented eating' versus 'Rice and Kimchi eating', odds ratio for hypertension, diabetes, metabolic syndrome and obesity significantly decreased after adjusting age and sex (OR=0.64, 0.73, and 0.85 respectively, 95% CI). Although our results were from a cross-sectional study, these imply that the dietary patterns were related to diseases.

A Study on the Silk Tabbies, Ju(細) and Si(總), Considering the Relationship between Ancient Korea and Ancient Japan (고대 한일 관계에서 본 평직 견직물 세(細), 총(總)에 관한 연구)

  • Jeon, Hyun-Sil;Kang, Soon-Che
    • Journal of the Korean Society of Costume
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    • v.61 no.4
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    • pp.117-137
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    • 2011
  • This study analyzed historical records on silk tabby-ju(細), Si(總)- in a diachronic and spatial point of view. The historical records were written in Samguksagi(三國史記) of Korea, Eastern barbarian[東弟] section of Ershiwush(二十五史) of China and Ritkokusi(六國史)of Japan from the $4^{th}$ century to the early $10^{th}$ century. The study finally could reach the conclusions as follow. Firstly, records that fabrics like Ju were used were found in the Korean historical documents written on Balhae(渤海) of the $8^{th}$ century and Sllla(新羅) of the $9^{th}$ century. On the other hand, no official record on production of fabrics like Ju was found in the Japanese historical documents up to the $10^{th}$ century. Instead, there are some records that Si was produced and used for the first time in the $7^{th}$ century and it was rapidly spread in the $8^{th}$ century. In the $9^{th}$ century, the number of records on Si was sharply decreased and the importance of Si in the foreign-relation point of view also went down gradually. Secondly, records on using and trading with both Ju(細) and Si(總)in the foreign relation of two countries were shown from the $8^{th}$ century to the $9^{th}$ century. In the period, international exchange had been promoted among Balhae, Silla and ancient Japan. In the $9^{th}$ century, fabrics like Ju of ancient Korea was introduced to ancient Japan ancient Japanese people could not manufacture Ju by themselves at that time. On this account, we assumed that ancient Japanese people might consider Ju as high quality fabric rather than Si that had been used as general fabric. Meanwhile, it is found that Japan presented various kinds of Si to Balhae and Silla from the early $8^{th}$ century. As the foreign relation between Sllia and ancient Japan got weaker in the mid-$8^{th}$ century, frequency and amount of supplying Si to Balhae were relatively increased. Besides Si, Balhae was given a lot of silk yarn and floss. These fabrics presumably were used as raw material of Ju in Balhae because Balhae got low output of silk due to its geographical condition.

Analysis of Aggravated Perfusion in Myocardial SPECT after Coronary Artery Bypass Surgery (관동맥우회로술 후에 심근 SPECT에 나타난 관류의 악화 분석)

  • Lee, Won-Woo;Yoon, Seok-Nam;Kim, Ki-Bong;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Lee, Dong-Soo
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.36-42
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    • 1997
  • Though myocardial perfusion was usually expected to improve after coronary artery bypass graft(CABG) surgery, some myocardial segments were aggravated after operation, as we compared perfusion changes on postoperative SPECT with preoperative ones. In this study, we evaluated perfusion changes after operation in rest and stress myocardial SPECT in 44 patients (M:F=25:19, age 57.1 $year{\pm}8.2$) who had CABG before and 3 months after operation. We tried to find out possible causes for perfusion aggravation with multivariate logistic regression analysis regarding whether bypass graft was artery or vein and which coronary artery territory was operated. Among 616 myocardial segments which were operated, 89(14.4%) aggravated after operation. In the univariate analysis, myocardial segments in the left circumflex arteries(LCx) aggravated more often(p<0.01) than others and segments having operative angioplasty did less often(p<0.01). Multivariate logistic regression revealed that LCx was risk factor for perfusion aggravation [odds ratio=2.54 (95% confidence interval : 1.53-4.22, p<0.01)]. However, this was not the case when we analysed in terms of arterial territories. Among 106 coronary arterial territories which were operated, 27(25.5%) aggravated. The territories having aggravated had similar characteristics regarding whether they received arterial or venous grafts, angioplasty and whether the operated territories were left anterior descending, right coronary or left circumflex arteries. In conclusion, myocardial segments in the left circumflex artery tended to aggravate more often after bypass surgery than the others. In short-term comparison of perfusion after surgery, we could not find any tendency that arterial or venous graft was associated with more frequency of the aggravation of perfusion after operation.

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Morphological and Genetic Stock Identification of Todarodes pacificus in Korean Waters (한국 주변해역에 서식하는 살오징어(Todarodes pacificus)의 형태 및 유전학적 계군분석)

  • Kim, Jeong-Yun;Yoon, Moon-Geun;Moon, Chang-Ho;Kang, Chang-Keun;Choi, Kwang Ho;Lee, Chung Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.18 no.3
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    • pp.131-141
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    • 2013
  • Stock identification of Todarodes pacificus collected in the East Sea, Yellow Sea and East China Sea during the period from September to December in 2011 was analyzed by morphometric characters and mitochondrial DNA (mtDNA) cytochrome oxidase subunit I (COI) gene nucleotide variations. Frequency distributions of mantle length was analyzed by morphological method with measuring size of T. pacificus. Then each stock was estimated to confirm their maturation for mean mantle length comparing with mean mature mantle length 20-22 cm. According to morphologic stock identification, it is estimated that the northern part of East Sea is categorized as summer stock and the rest parts, including mid /southern part of the East Sea, northern part of the East China Sea and northern part of the West Sea were autumn stock. For genetic analysis, a total 49 haplotypes were defined by 33 variable nucleotide sites. From the extensive haplotype diversity, limited nucleotide diversity and star-like shape of haplotype network, T. pacificus appears to have undergone rapid population expansion from an ancestral population with a small effective population size. Although pair-wise Fst estimates which represent genetic difference among groups were low, there are relatively remarkable difference of Fst between middle and southern part of the East Sea. Although middle part of the East Sea and southern part of the East Sea were situated at the East Sea, genetically separated groups were appeared.

Relationship between Social Work Self-efficacy and Career Decision Level and Career Preparation Behavior of University Students Majoring in Social Welfare (사회복지학 전공 대학생의 사회복지 자기효능감과 진로결정수준 및 진로준비행동과의 관계)

  • Jeong, Jin-Hee;Won, Mi-Soon;Lee, Soo-Jin
    • The Journal of the Korea Contents Association
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    • v.13 no.7
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    • pp.228-237
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    • 2013
  • This study was conducted to contribute to career counseling and career guidance for universities students majoring in social welfare by examining how the career decision level and the career preparation behavior of the students are and the relationship between social work self-efficacy and the career decision level and the career preparation behavior of the respondents. For this study, the social work self-efficacy, the levels of career decision making and career preparation-related behavior of 502 students of social welfare in five universities were measured. The frequency analysis, correlation analysis, multiple regression analysis were used for collected data analysis. The research findings are as follows. Firstly, the levels of career decision making and career preparation-related behavior were slightly lower than mid-point on 5 point scale respectively. Secondly, social work self-efficacy was not correlated to their career decision levels while social work self-efficacy positively affected to the career-related behavioral levels. In particular, the client support self-efficacy of the three sub-factors in social work efficacy had a negative influence on the levels of career preparation behavior. Consequently, social work self-efficacy of the participants intensively was correlated with their career preparation-related behavioral levels.

Breeding Behavior of Red Fox (Vulpes vulpes) in an Outdoor Breeding Facility (실외 번식시설에서 여우의 번식 행동)

  • Song, Dong-Ju;Song, Byeong-Cheol;Kwon, Jun-Hyeok;Shin, Pyeong-Kang
    • Korean Journal of Environment and Ecology
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    • v.32 no.1
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    • pp.47-54
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    • 2018
  • This study examined the behavior of red fox (Vulpes vulpes) during the estrus period, breeding period, and mating including the estrus period along as well as the effect of environmental factors in an outdoor breeding facility. The average mating duration was 19.95 min (n = 13, range = 1.17-35.25 min). The breeding season was mainly early February (56.6%) for foxes aged more than one year and mid-March (60.0%) for foxes aged less than one year. The mating duration was longest when both male and female were more than one year old ($24.4{\pm}11.08min$), although copulation took place regardless of partner's age. Females that mated twice within two days after estrus started or with two males had 100% pregnancy rate. In addition, the pregnancy rate was highest (87%) when both mating partners were more than one year old. Foxes preferred daytime to nighttime for mating, and thus mating usually took place on sunny days or between 10:00 and 12:00 on partly cloudy days. A male mated with different females for a maximum of five times, and the higher the mating frequency of a male, the longer the mating duration. Interest in mating decreased after three copulations in the case of males and after two copulations in the case of females. Males required at least 4 hours and 46 minutes between the first and second copulation. For this study, we collected reference data that might be applied to breeding programs for the red fox to secure the restoration of individuals of this important species.

Acoustic characteristics of sound field in partially opened rooms - Emphasis on horizontal coupling of diffuse and non-diffuse field - (실내공간의 부분적 개방에 따른 음향특성변화 I - 확산음장과 자유음장의 수평적 결합을 중심으로 -)

  • Jeong, Dae-Up;Choi, Young-Ji;Kim, Ji-Young;Oh, Yang-Ki;Choi, Seok-Ju
    • Journal of Korean Association for Spatial Structures
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    • v.7 no.2 s.24
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    • pp.105-114
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    • 2007
  • Large span spaces have been widely used for various purposes including sports events in other countries. Due to increasing demands on multi-purpose use of such spaces, recently built large span sport facilities such dome stadiums have been required to accommodate sport events as well as performing events. Also, retractable ceilings and/or walls were generally adopted in those spaces for providing various event conditions. It seems obvious that the openings between diffuse fields and free field may cause difficulties in the acoustic design of such spaces In the present work, the acoustic characteristics of non-diffuse field has been investigated using 1/10 acoustic scale models. It was found that RTs at low- and mid-frequencies decayed faster than those at high-frequencies as the percentage of opening area increased. The decay rate of RTs at high frequencies were not influenced by increasing the area of an opening. Also high dependence of EDT on the percentage of opening area was observed at all frequency range. D50 was not improved by increasing the area of an opening up to 12.5% and then sharply increased. The application of Schroeder integration to evaluate the reverberation charateristics of coupled spaces may not be proper, since non-exponential decay process with double or triple decays of those spaces can not be properly defined. EDT seems more appropriate to predict reverberation at the early acoustic design stage of acoustically coupled spaces.

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A COMPARATIVE STUDY ON ALTERATIONS OF FACIAL BONE FRACTURE PATIENTS VISITING PUSAN UNIV.-HOSPITAL EMERGENCY CENTER (응급실을 내원한 구강악안면외과 안면골 골절 환자의 변화에 대한 비교 연구)

  • Lee, Jung-Hoon;Kim, Yong-Deok;Shin, Sang-Hun;Kim, Uk-Kyu;Kim, Jong-Ryoul;Chung, In-Kyo
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.27 no.2
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    • pp.171-176
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    • 2005
  • Although there have been many clinical studies about the facial trauma in the recent as well as in the past, severity and frequency of facial trauma are reported multifarious. It seemed to be because of variety of social, cultural, and environmental factors, and the view point of investigators. In this study, we investigated about the patients visiting emergency room during recent 5 years(1999-2003), and compared with retrospective study during former 5 years(1992-1996) in Dept. OMS Pusan Univ-Hospital. We are assessed the cause, type, demographic ect. And analyzed alterations of facial bone fractures during past 2 periods. the results were as follows. The total number of patients was increased slightly. 429 patients treated for maxillofacial fractures between January 1992 and December 1996 and 466 patients treated between January 1992 and December 1996. The male-to-female ratio reduced in the second period by a factor of 0.7. Patients in the age groups of 10-19 years and 20-29 years increased by a factor of 4.2 and 7.9 in the second period. Assaults and falls in the second period decreased by a factor of 15.4 and 7.9. But, traffic accidents and slip downs in the second period increased by a factor of 6 and 6.6. The mandibular fractures(70.6%) showed the highest incidence, followed by zygomatic bone and arch fractures(7.5%), maxillary bone fractures(4.0%), and nasal bone fractures(4.0%). In the second period, the mid-face fracture was increased slightly. So, the mandibular fractures(69.0%) followed by maxillary bone fractures(12.9%), zygomatic bone and arch fractures(8.0%), nasal bone fractures(7.0%). Ramus fractures and body fractures of mandible was increased slightly in the second period.