Comparisons of hearing threshold changes in male workers with unilateral conductive hearing loss exposed to workplace noise

Sang Jin Park,Joo Hyun Sung,Chang Sun Sim,Seok Hyeon Yun,Jeong Han Yeom,Joong-Keun Kwon,Jiho Lee 대한직업환경의학회 2016 대한직업환경의학회지 Vol.28 No.-

Background: The purpose of this study was to investigate hearing threshold changes of workers with unilateral conductive hearing loss who were exposed to workplace noise for 8-years. Methods: Among 1819 workers at a shipyard in Ulsan, 78 subjects with an air-bone gap ≥10 ㏈HL in unilateral ears were selected. Factors that could affect hearing were acquired from questionnaires, physical examinations, and biochemistry examinations. Paired t-test was conducted to compare the hearing threshold changes over time between conductive hearing loss (CHL) ear and sensorineural hearing loss (SNHL) ear. Results: The study included male subjects aged 48.7 ± 2.9, having worked for 29.8 ± 2.7 years. Hearing thresholds increased significantly in CHL ears and SNHL ears at all frequencies (0.5–6 ㎑) during follow-up period (p < 0.05). The threshold change at 4 ㎑ was 3.2 ㏈HL higher in SNHL ears which was statistically significant (p < 0.05). When workers were exposed to noise levels of 85 ㏈A and above, threshold change at 4 ㎑ was 5.6 ㏈HL higher in SNHL ears which was statistically significant (p < 0.05). Among workers aged below 50, the threshold change values were lower in low-frequency (0.5–2 ㎑) in SNHL ears, with a small range of changes, whereas in high-frequency (3–6 ㎑), the range of changes was greater SNHL ears (p < 0.05). Among workers aged 50 and above, SNHL ears showed a wider range of changes in both high- and low-frequency areas (p < 0.05). Conclusions: At high-frequencies, particularly at 4 ㎑, the range of hearing threshold changes was lower in ears with conductive hearing loss than in contralateral ears. This is suggested as a protective effect against noise exposure.

Abrupt Morphology Change upon Thermal Annealing in Poly(3-Hexylthiophene)/Soluble Fullerene Blend Films for Polymer Solar Cells

Shin, Minjung,Kim, Hwajeong,Park, Jiho,Nam, Sungho,Heo, Kyuyoung,Ree, Moonhor,Ha, Chang-Sik,Kim, Youngkyoo WILEY-VCH Verlag 2010 Advanced Functional Materials Vol.20 No.5

<P>The in situ morphology change upon thermal annealing in bulk heterojunction blend films of regioregular poly(3-hexylthiophene) (P3HT) and 1-(3-methoxycarbonyl)-propyl-1-phenyl-(6,6)C<SUB>61</SUB> (PCBM) is measured by a grazing incidence X-ray diffraction (GIXD) method using a synchrotron radiation source. The results show that the film morphology—including the size and population of P3HT crystallites—abruptly changes at 140 °C between 5 and 30 min and is then stable up to 120 min. This trend is almost in good agreement with the performance change of polymer solar cells fabricated under the same conditions. The certain morphology change after 5 min annealing at 140 °C is assigned to the on-going thermal transition of P3HT molecules in the presence of PCBM transition. Field-emission scanning electron microscopy measurements show that the crack-like surface of blend films becomes smaller after a very short annealing time, but does not change further with increasing annealing time. These findings indicate that the stability of P3HT:PCBM solar cells cannot be secured by short-time annealing owing to the unsettled morphology, even though the resulting efficiency is high.</P> <B>Graphic Abstract</B> <P>The morphology of P3HT:PCBM blend films, one of the most widely used material blends in polymer solar cells, is monitored using in situ grazing angle X-ray diffraction (GIXD). The study reveals abrupt changes in the nanostructure with annealing time (see image, OOP = out-of-plane), which is in good agreement with variations in device performance (PCE = power conversion efficiency; FF = fill factor). <img src='wiley_img_2010/1616301X-2010-20-5-ADFM200901655-content.gif' alt='wiley_img_2010/1616301X-2010-20-5-ADFM200901655-content'> </P>

표면저항형 ITO 필름 센서의 표면처리 공정에 관한 연구

김동준(Dongjun Kim),안상수(Sangsu An),이창한(Changhan Lee),조영지(Youngji Cho),한민철(Mincheol Han),배찬영(Chanyoung Bae),전준수(Junsu Jeon),송유진(Yujin Song),장지호(Jiho Chang),하윤수(Yun-Su Ha),박재진(Jae-Jin Park),이문진(Moonjin Lee 한국물리학회 2024 새물리 Vol.74 No.1

표면저항의 변화를 이용하여 수중 유해화학물질 농도를 측정할 수 있는 센서를 금속산화물 나노입자 필름을 이용하여 제작하고 표면처리 공정에 의한 센서 성능의 변화를 연구하였다. 필름 인쇄에 사용한 유기 바인더의 표면 잔류에 의한 영향에 주목하여 필름과 센서의 물성 변화를 관찰하였다. 잔류 바인더를 제거하기 위하여 기존의 소결 공정에 세척 공정을 추가로 도입하여 세척 시간에 따른 ITO:CB 필름의 물성 변화를 관찰하였고, 표면처리 시간을 최적화하였다. 세척 시간을 증가시킴에 따라 센서 응답이 개선됨을 확인하였고 양호한 센서 동작을 확보하기 위한 최적의 표면처리 조건을 결정하였다. A sensor that can measure the concentration of harmful chemicals in water using changes in surface resistance was fabricated using a metal oxide nanoparticle film, and the changes in sensor performance due to surface treatment processes were investigated. The influence of the surface residue of the organic binder used for film printing was focused on, and the changes in the properties of the film and sensor were observed. To remove the residual binder, a cleaning process was additionally introduced to the existing sintering process, and the changes in the properties of the ITO:CB film were observed according to the cleaning time, and the surface treatment time was optimized. It was confirmed that the sensor response improved as the cleaning time increased, and the optimal surface treatment conditions were determined to ensure good sensor operation.

Searching for Antibacterial Materials to Extend the Shelf Life of Salted Fish

JiHo YANG,HyunJung LEE,Hyun Jin JO,Jung Hwan OH,Fatih KARADENIZ,Mi-Soon JANG,Chang-Suk KONG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

Natural seasonings are the recent trend in food industry to replace the synthesized seasonings due to consumer preference. However, unexpected results may occur in terms of sensory evaluation and physico-chemical properties such as reduced flavor and color change by adding natural seasoning. In this study, by evaluating and comparing the antioxidant and antibacterial activities of 10 marine algae extracts, we tried to find a marine alga extract that helps to extend the shelf life of salted pollack roe which also can be applied as a functional material with antibacterial activity. Among tested species, in DPPH free radical scavenging activity and total polyphenols content, Ecklonia cava and Gracilaria verrucosa extracts showed significant antioxidant activity and in paper disc diffusion, MIC and MBC tests, Ecklonia cava, Codium flagile and Gracilaria verrucosa extracts showed significant antibacterial activity. Based on the current results, marine algae extracts were suggested to help to extend the shelf life of salted pollack roe acting as functional materials with antioxidant and antibacterial activities.

Design a switch wrapper for SNA on-chip-network

Jiho Chang,Jongsu Yi,JunSeong Kim 대한전자공학회 2005 ITC-CSCC :International Technical Conference on Ci Vol.2005 No.1

Effects of Artemisia scoparia on Melanin Synthesis in B16F10 Melanoma Cells

JiHo YANG,HyunJung LEE,Hyun Jin JO,Jung Hwan OH,Fatih KARADENIZ,Youngwan SEO,Chang-Suk KONG 한국생물공학회 2021 한국생물공학회 학술대회 Vol.2021 No.10

Natural seasonings are the recent trend in food industry to replace the synthesized seasonings due to consumer preference. However, unexpected results may occur in terms of sensory evaluation and physico-chemical properties such as reduced flavor and color change by adding natural seasoning. In this study, by evaluating and comparing the antioxidant and antibacterial activities of 10 marine algae extracts, we tried to find a marine alga extract that helps to extend the shelf life of salted pollack roe which also can be applied as a functional material with antibacterial activity. Among tested species, in DPPH free radical scavenging activity and total polyphenols content, Ecklonia cava and Gracilaria verrucosa extracts showed significant antioxidant activity and in paper disc diffusion, MIC and MBC tests, Ecklonia cava, Codium flagile and Gracilaria verrucosa extracts showed significant antibacterial activity. Based on the current results, marine algae extracts were suggested to help to extend the shelf life of salted pollack roe acting as functional materials with antioxidant and antibacterial activities.

A Mixed-order Ambisonics for Improving Horizontal Performances

Jiho Chang(장지호),Marton Marschall 한국소음진동공학회 2016 한국소음진동공학회 학술대회논문집 Vol.2016 No.10

투영된 패턴과 원영상의 합성을 이용한 스테레오 매칭

장지호 ( Jiho Chang ),정재찬 ( Jae-chan Jeong ),조재일 ( Jae-il Cho ) 한국정보처리학회 2013 한국정보처리학회 학술대회논문집 Vol.20 No.2

기존의 스테레오 매칭 시스템은 얻어지는 영상에 따라 disparity의 결과가 크게 차이를 나타내게 된다. 이러한 오류를 줄이고자 일정한 패턴을 주사하여 스테레오 매칭을 계산하는 방식인 액티브 스테레오 기법이 대두되고 있다. 본 논문에서는 이러한 액티브 스테레오 매칭을 사용시에 얻어질 수 있는 패턴영상과 패턴이 없는 원영상을 서로 조합하여 스테레오 매칭을 수행함으로서 정확한 disparity를 얻고자 한다. 이러한 영상의 합성시에 두 영상의 비율에 따라서, 얻어지는 영상의 밝기 구성에 따라서 disparity결과의 차이와 이를 실제 시스템을 구성시에 필요한 점에 대해서 확인하고자 한다.

트랜스포머 구조를 사용한 이미지 캡셔닝에서 객체 관계 인코딩 방법

장지호(Jiho Chang) 대한전자공학회 2020 대한전자공학회 학술대회 Vol.2020 No.8

이미지 캡셔닝은 주어진 이미지를 가장 잘 설명하는 문장을 생성하는 문제로서 최근에는 bottom-up 및 top-down attention 및 트랜스포머 구조의 조합이 널리 사용되고 있다. 트랜스포머는 자연어 처리와 같은 시퀀스-시퀀스 전환에서 사용되는 것으로 이를 이미지 캡셔닝에서제성능을 향상시키기 위해 다양한 방법이 제안되었다. 이 논문에서는 기존의 자연어 처리를 위한 트랜스포머의 위치 인코딩(posional encoding)과 같은 어텐션 모듈(attention module)을 대체하기 위해 검출된 객체 사이의 관계 인코딩을 사용하여 성능을 향상하고자 한다. 검출된 물체 사이의 관계를 사용하는 방법이 정량적 및 정성적 평가를 통해 이미지 캡셔닝 결과에 어떻게 영향을 미치는지 확인하고 트렌스포머 구조를 사용할 때 성능을 개선하는 방법을 제안하고자 한다. 이 논문에서는 Facebook에서 시퀀스 모델링 툴킷으로 제공되는 FAIRSEQ를 기반으로 MS-coco 2014 캡션 데이터 세트를 사용하여 실험을 수행하여, 다양한 관계를 사용하여 인코딩을 적용한 결과, 정량적 평가에서 개선이 기본 트랜스포머 위치 인코딩보다 크지 않지만 정성적 평가에서 이미지가 훨씬 잘 설명됨을 확인하였다.

디즈니 애니메이션 <뮬란>을 통해 본 중국전통 서사에 대한 미국의 인식과 해석의 차이연구

장침 ( Chang Chim ),신지호 ( Shin Jiho ) 한국디지털영상학회 2016 디지털영상학술지 Vol.13 No.-

The poem of Mulan is a famous literary works in China. The story of Mulan was spread by words of mouth and reproduced by performance, which was brought forth the new and expanded. Mulan`s impact on people is still respected. Mulan`s loyalty and filial piety are deep-rooted in our minds. In 1998, the cartoon Mulan made by Disney Corporation got a box-office success all over the world, which has aroused significant attention. The story was performed not all the same with Chinese, but it was enjoyed and accepted by the audience all over the world .The cartoon displays Chinese culture to Americans and make Chinese audience increase knowledge of American culture and Chinese elements in their eyes. The Mulan`s story in the Disney`s version was based on accepting and reserving the Chinese traditional culture. Instilling American value into it which combines western free thought and eastern mystery classic perfectly . The film not only catered to the audience in China and the USA, even meet the taste of the global audience. When the cartoon Mulan made by Disney was released in China, the evaluation of the cartoon is mixed. But there`s no doubt that the Chinese elements in cartoon have changed . The article regards the cartoon Mulan made by Disney as research object and contrast as research methods. Trying to study the cognitive competence of culture between China and America. From that we can make communication and fusion of different cultures in the East and West and we can get clear with that.