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Situating the Anthropocene: The Social Construction of the Pohang 'Triggered' Earthquake (인류세 맥락화하기: 포항 '촉발지진'의 사회적 구성)

  • KIM, Kiheung
    • Journal of Science and Technology Studies
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    • v.19 no.3
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    • pp.51-117
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    • 2019
  • On 15th November 2017, the coastal city of Pohang, located in the Southeastern part of South Korea was shaken by a magnitude 5.4 earthquake. The earthquake displaced more than 1,700 residents and caused more than $ 300 million dollars of economic loss. It was the second most damaging earthquake in the history of Korea. Soon after the earthquake, a group of scientists raised a possible link between the first Enhanced Geothermal System (EGS) project and the earthquake. At the same time, another group of scientists put forward a different hypothesis of the causation of the earthquake claiming that it was caused by the geological movements that were initiated by the Great Tohoku Earthquake in 2011. Since then, there were scientific debates between the two different groups of scientists. The scientific debate on the causation of the earthquake has been concluded temporarily by the Research Investigatory Committee on the Pohang Earthquake in 2019. The research committee concluded that the earthquake was caused by the Pohang EGS system: this means that the earthquake can be defined not as a natural earthquake, but as an artificially triggered earthquake. This article is to examine the Pohang earthquake can be defined as an Anthropocenic event. The newly suggested concept, the Anthropocene is a relatively novel term to classify the earthly strata and their relationship to geological time. The current geological period should be defined by human activities and man-made earthly environment. Although the term is basically related to geological classification, the Anthropocene has been widely debated amongst humanist and social science scholars. The current disastrous situation of our planet also implies with the Anthropocene. This paper is to discuss how to understand anthropogenic events. In particular, the paper pays attention to two different scholarly positions on the Anthropocene: Isabelle Stenger's Gaia theory and Barbara Herrnstein Smith's relativist theory. The former focuses on the earthly inevitable catastrophe of Anthropocene while the latter suggests to situate and contextualise anthropogenic events. On the basis of the theoretical positions, the article is to analyse how the Pohang earthquake can be located and situated.

Effects of Head Posture on the Rotational Torque Movement of Mandible in Patients with Temporomandibular Disorders (두경부 위치에 따른 측두하악장애환자의 하악 torque 회전운동 분석)

  • Park, Hye-Sook;Choi, Jong-Hoon;Kim, Chong-Youl
    • Journal of Oral Medicine and Pain
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    • v.25 no.2
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    • pp.173-189
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    • 2000
  • The purpose of this study was to evaluate the effect of specific head positions on the mandibular rotational torque movements in maximum mouth opening, protrusion and lateral excursion. Thirty dental students without any sign or symptom of temporomandibular disorders(TMDs) were included as a control group and 90 patients with TMDs were selected and examined by routine diagnostic procedure for TMDs including radiographs and were classified into 3 subgroups : disc displacement with reduction, disc displacement without reduction, and degenerative joint disease. Mandibular rotational torque movements were observed in four head postures: upright head posture(NHP), upward head posture(UHP), downward head posture(DHP), and forward head posture(FHP). For UHP, the head was inclined 30 degrees upward: for DHP, the head was inclined 30 degrees downward: for FHP, the head was positioned 4cm forward. These positions were adjusted with the use of cervical range-of-motion instrumentation(CROM, Performance Attainment Inc., St. Paul, U.S.A.). Mandibular rotational torque movements were monitored with the Rotate program of BioPAK system (Bioresearch Inc., WI, U.S.A.). The rotational torque movements in frontal and horizontal plane during mandibular border movement were recorded with two parameters: frontal rotational torque angle and horizontal rotational torque angle. The data obtained was analyzed by the SAS/Stat program. The obtained results were as follows : 1. The control group showed significantly larger mandibular rotational angles in UHP than those in DHP and FHP during maximum mouth opening in both frontal and horizontal planes. Disc displacement with reduction group showed significantly larger mandibular rotational angles in DHP and FHP than those in NHP during lateral excursion to the affected and non-affected sides in both frontal and horizontal planes(p<0.05). 2. Disc displacement without reduction group showed significantly larger mandibular rotational angles in FHP than those in any other head postures during maximum mouth opening as well as lateral excursion to the affected and non-affected sides in both frontal and horizontal planes. Degenerative joint disease group showed significantly larger mandibular rotational angles in FHP than those in any other head postures during maximum mouth opening, protrusion and lateral excursion in both frontal and horizontal planes(p<0.05). 3. In NHP, mandibular rotational angle of the control group was significantly larger than that of any other patient subgroups. Mandibular rotational angle of disc displacement with reduction group was significantly larger than that of disc displacement without reduction group during maximum mouth opening in the frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of disc displacement with reduction group or degenerative joint disease group during maximum mouth opening in the horizontal plane(p<0.05). 4. In NHP, mandibular rotational angles of disc displacement without reduction group were significantly larger than those of the control group or disc displacement with reduction group during lateral excursion to the affected side in both frontal and horizontal planes. Mandibular rotational angle of disc displacement without reduction group was significantly smaller than that of the control group during lateral excursion to the non-affected side in frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of disc displacement with reduction group during lateral excursion to the non-affected side in the horizontal plane(p<0.05). 5. In NHP, mandibular rotational angle of the control group was significantly smaller than that of disc displacement with reduction group or disc displacement without reduction group during protrusion in the frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of the disc displacement with reduction group or degenerative joint disease group during protrusion in the horizontal plane. Mandibular rotational angle of the control group was significantly smaller than that of disc displacement without reduction group or degenerative joint disease group during protrusion in the horizontal plane(p<0.05). 6. In NHP, disc displacement without reduction group and degenerative joint disease group showed significantly larger mandibular rotational angles during lateral excursion to the affected side than during lateral excursion to the non-affected side in both frontal and horizontal planes(p<0.05). The findings indicate that changes in head posture can influence mandibular rotational torque movements. The more advanced state is a progressive stage of TMDs, the more influenced by FHP are mandibular rotational torque movements of the patients with TMDs.

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Some Instances of Manchurian Naturalization and Settlement in Choson Dynasty (향화인의 조선 정착 사례 연구 - 여진 향화인을 중심으로 -)

  • Won, Chang-Ae
    • (The)Study of the Eastern Classic
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    • no.37
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    • pp.33-61
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    • 2009
  • In the late Koryo period, until 14th century, there had been at least two groups of Manchurians who were conferred citizenships; one group was living as an original inhabitant in the coastal area of north­eastern part of Korean peninsular, long time ago, and they were over one thousand households. The other was coming down from inland, eastern part of Yoha River, to the area of Tuman River to settle down and they were at least around one hundred and sixty households, including such tribes as Al-tha-ry, Ol-lyang-hap, Ol-jok-hap and others. They were treated courteously, from the early days of Choson dynasty, with governmental policies in an economic, political, and social ways. They were given, for instance, a house, a land, household furniture, and clothes. They were allowed to get marry with a native Korean to settle down. They were educated how to cultivate their lands. It was also possible for them to be given an official position politically or allowed to take a National Civil Official Examination. The fact they could take such an Examination, in particular, means they were treated fairly and equally, because they also had a privilege to improve their social positions through the formal system as much as common people. Two typical families were scrutinized, in this paper, family Chong-hae Lee and family Chon-ju Ju. All of them were successful to settle down with different backgrounds each other. The former were from a headman, Lee Jee-ran, who controlled his tribe, over five hundred households. He was given three titles of a meritorious retainer at the founding of Chosun dynasty, at the retrieval of armies, and an enshrined retainer. His son, Lee Wha-yong, was also given a vassal of merit who kept a close tie successfully with the king's family through a marriage. Upon the foundation of their ancestors, their grandsons, family Lee Hyo-yang and family Lee Hyo-gang, each, had taken solid root as an aristocratic Yang-ban class. The former became a high officer family, generation by generation, while the latter changed into a civil official family through Civil Official Examinations. They lived mainly around Seoul, Kyong-gi Province and some lived in their original places, Ham-kyong Province. Chu-man, the first ancestor, was given a meritorious retainer at the founding of the dynasty and Chu-in was also given a high officer position from the government. They kept living at the original place, Ham-heung, Ham-kyong Province, and then became an outstanding local family there. They began to pass the Civil Official Examinations. After 17th century on the passers were 17 in Civil Official Examinations and 40 were passed in lower civil examinations. The positions in government they attained usually were remonstrance which position was prohibited particularly to North­Western people at that time. The Chosun dynasty was open to Machurians widely through the system of envoy, convoy, and naturalization. It was intended to build up an enclosure policy through a friendly diplomatic relation with them against any possible invasion from outside. This is one reason why they were supported fully that much in a various way.

Media Scholars and Power: The politicized intellectuals hanging on the dangerous rope (언론학자와 권력: 정치화된 지성의 위험한 줄타기)

  • Choi, Nakjin;Kim, Sunghae
    • Korean Journal of Legislative Studies
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    • v.22 no.2
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    • pp.113-156
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    • 2016
  • Media scholars take a lion stake in power circle. Not only do they take a part in media policies but seize prestigious positions like board members in Korea Communication Commission(KCC). Unfortunately, though, little has been known about who they are, what qualifications they have, and whether they meet public interests. This paper attempts to unveil the mechanism of those politicized intellectuals who are specialized on the media. Two categories divided into 'representative' and 'expertise' are employed for this purpose. On the one hand, the representative means the degree of committment into such public services as participation in conferences or non-profit organizations. On the other hand, the number of research articles, books and projects belong to the expertise. Evaluation levels consist of 'excellence, good and average' were allocated to those scholars who are(were) in 'Power Hole,' where decision makings come into being. Some interesting observations were made though this study. First of all, such criteria as representative and expertise vaguely suggested by the laws were hardly fit into those intellectuals, Rarely did they commit into public service let alone showing vigilance in academic activities. Secondly, both ideological loyalty and political activities in line with the government had much to do with taking such positions. Thirdly, not surprisingly, it showed that to graduate from Seoul National University and have Ph.D. degree from U.S.A. was one of the most essential factors. In final, most of them were very good at taking advantage of the press in way of boosting their publicity. To attend at policy making processes either in form of board members or advisers is inevitable for media experts. However, as shown in this study, such qualification of public service and academic eagerness shouldn't be underestimated. Academic integrity not selling intelligence solely for private interests needs to be protected as well. The authors hope this study to provide a valuable opportunity to establish a kind of ethical standards in participating into politics.

A Study on the Consciousness of Landscape Planting Practitioner about the Measurement Criteria of the Root Diameter of Landscape Trees in the Landscape Planting Construction, in Korea (우리나라 조경식재공사의 근원직경 측정기준에 대한 조경식재 실무자들의 의식)

  • Han, Yong-Hee;Min, Jong-Il;Kim, Do-Gyun
    • Journal of the Korean Institute of Landscape Architecture
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    • v.49 no.2
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    • pp.27-40
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    • 2021
  • This study was carried out for the description of the conflicts on the measurement of the root collar diameter of the landscape trees that are currently being produced, distributed, and planted in S. Korea, and for determination of the standard for root collar diameter measurement. The difference in consciousness of appropriate measurement of root collar diameter among different ages of landscape practitioners was statistically significant at p<0.05 level. It seemed to be due to the difference in the amount of field experiences among different age groups. On "the ambiguity of measuring the root collar diameter' of landscape trees", the consciousness was significantly different at p<0.05 level among job positions. On "Improvement of measurement criteria for landscape trees," it was significantly different at p<0.05 level among job types. This was thought to be due to the disagreement between the client and the contractor. On "prevention of topsoil removal" when excavating landscape trees, the consciousness was significantly different at p<0.001 level among different age groups, and different at p<0.01 level among different occupations, and different at p<0.05 level among different working area. The consciousness on "removing top soil when excavating landscape trees and rooting after transplantation" was not significantly different. The consciousness on the conflict caused by "ambiguity in root collar diameter measurement criteria" was high with an average of 3.85 for job type, occupation, jop position, and work experience. It was higher for landscape contractors than public institutions. The higher job positions and more experiences, the more conflicts. The consciousness on the appropriate position of root collar diameter measurement for landscape trees revealed that measuring at above-ground part (66.5%) was prefered to the underground part (33.0%). During the excavation of landscape trees for transplant, topsoil removal up to average depth of -2cm to -4cm was favored by 84.0%, and the purpose of removing topsoil was recognized as 'to increase the size and unit cost' by 59.7%.

A Study on Hyangcheong and Jakcheong's Official Duties and Personnel Practices of Anbyeon of Hamgyeong Province in the 19th century - Focusing on an article of 'a list of Hyangcheong and Jakcheong's officials' - (19세기(世紀) 함경도(咸鏡道) 안변(安邊)의 향청(鄕廳)·작청(作廳) 직임(職任)과 인사관행(人事慣行) - '향청·작청 직임 명단' 문서를 중심으로 -)

  • Park, Kyoung ha
    • Journal of Korean Historical Folklife
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    • no.44
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    • pp.145-176
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    • 2014
  • This study analyzed official duties and personnel practices of Hyangcheong(鄕廳), administrative organization in which sajok(士族) participate this office, and Jakcheong(作廳), hyangree(鄕吏)'s office, of Anbyeon of Hamgyeong Province in the 19th century. Although there have beeen somewhat of case study of Gyeongsang, Honam, etc., study on Hamgyeong Province has been almost nonexistent because of the limitation of materials. Hence, this paper specifically examined Hyangcheong and Jakcheong's official duties and personnel practices through an article of 'a list of Hyangcheong and Jakcheong's officials' of Anbyeon, newly found, which is in the possession of this writer. Especially, this study virtually traced individual ststus and family by analyzing Hyangcheong and Jakcheong's 40-official duties and a list of 330-ofiicial duties for sixs years. And then by comparing it against Jokbo(族譜), I have grasped 19-Famlily of them. Executives of Hyangcheong could be grasped as they were status of Yangban(兩班), but members of Jakcheong were hardly identified because they were status of hyangree, thus most of them were not enscrolled in Jokbo. Hyangcheong and Jakcheong's official duties could be found by compare it with other area in Ehubgi(邑誌) Hamgyeong Province. the features of officiak duties are as in the following. On general administrative organization, Sajok's Hayngcheong, Jakcheong as general administrative organization and Jangcheong(將廳) as police work existed. As Pyeongando and Hamgyeongdo were border areas, Jangcheong was independent and led other institutions. However, in Anbyeon, Hojang(戶長) of Hayngcheong and Jakcheong divided dudies and commanded. Hojang'role was higher than any other areas, Because Hojang is in charge of Jangcheong's functions. Jakcheong was centrally operated by Hojang, Eebang(吏房), and Hyeongbang(刑房), so-called 'Samgonghyeong(三公兄)', Whereas Anbyeon was operated by Hojang, Eebang, Chunchong(千摠). In the general areas, While Juasu(座首) Byeolgam(別監), Executive of Hyangcheong, manages each warehouse(倉) where the nation's tax revenues are kept, In Anbyeon besides Joasu, Hyangso(鄕所). The principle of Hyangcheong and Jakcheong's personnel practices was one-period, but there were many consecutive terms, every other year terms, or tranference into other area. Police work was assumed by specific persons because it was relatively specialized job, However in case of Ghamsaek(監色) of each warehouse(倉), Hyangso(鄕所) of Hyangcheong or Hojang of Jakcheong had held plural offices, and was solely responsible it. On the overall features of its operation, Hyangcheong held plural offices, but rotation was made only within Hyangcheong. On the other hand, in the case of Jakcheong, Hojang, Eebang, and even Buriebang circulated their positions, but the other Hyangree rotated each Saek(色) and Guamguan of each warehouse(倉). This writer confirmed that unlike Gyeongsang and Hamgyeong, Hyangcheoung or duties of Hyangree were not handed from generation to generation by several families and, many families shared their work by circulating positions.

Hwangsang's Exchanges with Chusa Family and Poetic Embodiment (황상(黃裳)의 추사가(秋史家)와의 교류와 시적 형상화)

  • Gu, sawhae;Kim, gyusun
    • (The)Study of the Eastern Classic
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    • no.59
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    • pp.157-181
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    • 2015
  • This thesis pursued exchanges of Hwangsang with Chusa Family, who existed in the 19th century. What was Chusa to Hwangsang and what was Hwangsang to Chusa? The answer is concluded to the question of which existence Chusa was to Hwangsang but not of which existence Hwangsang was to Chusa. However, disregarding social positions of the nobles and the commoners, brothers of Chusa also cherished Hwangsang and respectfully treated him as a poet at all times. Chusa was a critic who recognized Hwangsang as a successor to Dasan poetics and became a patron of the literary circles on the other hand. Hwangsang's Chinese poems related to Chusa Family are counted as 45 JE 52 SU in total which consist of 31 JE 34 SU in "CHIWONYUGO" and 14 JE 18 SU in "CHIWONSOGO", On the other hand, Chinese poems which Chusa wrote for Hwangsang are only a few pieces shown in "WANDANGJEONJIP". Hwangsang first met three brothers including Chusa in September 1853 when he came up to the capital for the 4th time. Jeong Hak-yeon, the oldest son of Dasan Jeang Yak-yong, played an important role in the whole process that Hwangsang met Chusa's three brothers and was recognized as a poet. As the oldest son of Dasan Family, Jeong Hak-yeon made efforts in various ways for Hwangsang. Hwangsang tried his efforts to exhibit his ability as a poet to Chusa and to get Chusa's introduction of his poetical works. Considering Chusa's importance in then literary circles, the introduction seemed to reflect recognition by the literary circles in the metropolis and it also showed that Hwangsang was no more than an obscure poet in the provincial area. Poetical composition of Hwangsang for Chusa three brothers commonly contained friendship, intimacy and special respect at all times. Seeing from exchange process between Hwangsang and Dasan Family or Chusa Family, it is found that mutual exchanges were actively made in the mid-nineteenth century overcoming regional differentiation between capital and province, or feudalism class distinction of social positions of the nobles and the commoners.

Dynamic Equilibrium Position Prediction Model for the Confluence Area of Nakdong River (낙동강 합류부 삼각주의 동적 평형 위치 예측 모델: 감천-낙동강 합류점 중심 분석 연구)

  • Minsik Kim;Haein Shin;Wook-Hyun Nahm;Wonsuck Kim
    • Economic and Environmental Geology
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    • v.56 no.4
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    • pp.435-445
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    • 2023
  • A delta is a depositional landform that is formed when sediment transported by a river is deposited in a relatively low-energy environment, such as a lake, sea, or a main channel. Among these, a delta formed at the confluence of rivers has a great importance in river management and research because it has a significant impact on the hydraulic and sedimentological characteristics of the river. Recently, the equilibrium state of the confluence area has been disrupted by large-scale dredging and construction of levees in the Nakdong River. However, due to the natural recovery of the river, the confluence area is returning to its pre-dredging natural state through ongoing sedimentation. The time-series data show that the confluence delta has been steadily growing since the dredging, but once it reaches a certain size, it repeats growth and retreat, and the overall size does not change significantly. In this study, we developed a model to explain the sedimentation-erosion processes in the confluence area based on the assumption that the confluence delta reaches a dynamic equilibrium. The model is based on two fundamental principles: sedimentation due to supply from the tributary and erosion due to the main channel. The erosion coefficient that represents the Nakdong River confluence areas, was obtained using data from the tributaries of the Nakdong River. Sensitivity analyses were conducted using the developed model to understand how the confluence delta responds to changes in the sediment and water discharges of the tributary and the main channel, respectively. We then used annual average discharge of the Nakdong River's tributaries to predict the dynamic equilibrium positions of the confluence deltas. Finally, we conducted a simulation experiment on the development of the Gamcheon-Nakdong River delta using recorded daily discharge. The results showed that even though it is a simple model, it accurately predicted the dynamic equilibrium positions of the confluence deltas in the Nakdong River, including the areas where the delta had not formed, and those where the delta had already formed and predicted the trend of the response of the Gamcheon-Nakdong River delta. However, the actual retreat in the Gamcheon-Nakdong River delta was not captured fully due to errors and limitations in the simplification process. The insights through this study provide basic information on the sediment supply of the Nakdong River through the confluence areas, which can be implemented as a basic model for river maintenance and management.

Effects of vowel types and sentence positions in standard passage on auditory and cepstral and spectral measures in patients with voice disorders (모음 유형과 표준문단의 문장 위치가 음성장애 환자의 청지각적 및 켑스트럼 및 스펙트럼 분석에 미치는 효과)

  • Mi-Hyeon Choi;Seong Hee Choi
    • Phonetics and Speech Sciences
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    • v.15 no.4
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    • pp.81-90
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    • 2023
  • Auditory perceptual assessment and acoustic analysis are commonly used in clinical practice for voice evaluation. This study aims to explore the effects of speech task context on auditory perceptual assessment and acoustic measures in patients with voice disorders. Sustained vowel phonations (/a/, /e/, /i/, /o/, /u/, /ɯ/, /ʌ/) and connected speech (a standardized paragraph 'kaeul' and nine sub-sentences) were obtained from a total of 22 patients with voice disorders. GRBAS ('G', 'R', 'B', 'A', 'S') and CAPE-V ('OS', 'R', 'B', 'S', 'P', 'L') auditory-perceptual assessment were evaluated by two certified speech language pathologists specializing in voice disorders using blind and random voice samples. Additionally, spectral and cepstral measures were analyzed using the analysis of dysphonia in speech and voice model (ADSV).When assessing voice quality with the GRBAS scale, it was not significantly affected by the vowel type except for 'B', while the 'OS', 'R' and 'B' in CAPE-V were affected by the vowel type (p<.05). In addition, measurements of CPP and L/H ratio were influenced by vowel types and sentence positions. CPP values in the standard paragraph showed significant negative correlations with all vowels, with the highest correlation observed for /e/ vowel (r=-.739). The CPP of the second sentence had the strongest correlation with all vowels. Depending on the speech stimulus, CAPE-V may have a greater impact on auditory-perceptual assessment than GRBAS, vowel types and sentence position with consonants influenced the 'B' scale, CPP, and L/H ratio. When using vowels in the voice assessment of patients with voice disorders, it would be beneficial to use not only /a/, but also the vowel /i/, which is acoustically highly correlated with 'breathy'. In addition, the /e/ vowel was highly correlated acoustically with the standardized passage and sub-sentences. Furthermore, given that most dysphonic signals are aperiodic, 2nd sentence of the 'kaeul' passage, which is the most acoustically correlated with all vowels, can be used with CPP. These results provide clinical evidence of the impact of speech tasks on auditory perceptual and acoustic measures, which may help to provide guidelines for voice evaluation in patients with voice disorders.

Analysis of Ventilation Characteristics in Ship Fuel-Preparation Rooms During Ammonia Leakage (암모니아 누출 시 선박 연료 준비실의 환기 특성 분석)

  • Jin-Woo Bae;Bo Rim Ryu;Kweon-Ha Park
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.30 no.5
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    • pp.490-498
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    • 2024
  • Ammonia is an eco-friendly marine fuel that does not emit carbon dioxide and is a primary contributor to global warming. Despite its benefits, ammonia poses significant risks owing to its toxicity, explosiveness, and corrosiveness, thus necessitating robust safety measures to manage its potential leaks on ships. This study investigates the characteristics of ammonia leaks and ventilation dynamics in a ship fuel-preparation room, with emphasis on the ef ect of varying the positions of air supply and exhaust outlets. The leakage rate is set at 0.1 kg/s, with a ventilation rate of 30 ACH (air changes per hour). The scenario with air supply at Aft - Top - Stbd and exhaust at Fwd - Top - Stbd (Case 1) results in the highest average ammonia concentration after 100 s. Conversely, the scenario with air supply at Aft - Bottom - Stbd and exhaust at Fwd - Bottom - Port (Case 14) results in the lowest concentration. After 50 s, Case 1 indicate ammonia concentrations exceeding 1500 ppm toward Aft, whereas Case 14 indicate a consistent stagnation zone along the Fwd wall. The distribution of ammonia concentration and velocity varies by height owing to the positioning of the air supply and exhaust outlets as well as the equipment configuration, thus resulting in higher concentrations in areas with slower airflow. When a small amount of ammonia leaked at 0.1 kg/s for 10 s, explosive gas formed near the leak point at a height of approximately 1 m, thus indicating an extremely low risk of explosion from slight ammonia leaks. This study confirms that the optimal combination of air supply and exhaust-duct positions can effectively control ammonia concentration. This finding is expected to contribute to the establishment of design standards and ensure safety when using ammonia as marine fuel.