로드헤더 장비사양 검토 및 굴착효율 예측 모델 개발

정재훈,임주휘,이재원,강한별,김도훈,신영진,Jae Hoon Jung,Ju Hyi Yim,Jae Won Lee,Han Byul Kang,Do Hoon Kim,Young Jin Shin 한국터널지하공간학회 2023 한국터널지하공간학회논문집 Vol.25 No.3

The use of roadheaders has been increasing to mitigate the problems of noise and vibration during tunneling operations in urban area. Since lack of experience of roadheader for hard rock, the selection of appropriate machines and the evaluation of cutting rates have been challenging. Currently, empirical models developed overseas are commonly used to evaluate cutting rates, but their effectiveness has not been verified for domestic rocks. In this paper, a comprehensive literature review was conducted to assess the rock cutting force, cutterhead capacity, and cutting rate to select the appropriate machine and evaluate its performance. The cutterhead capacity was reviewed based on the literature results for the site. Furthermore, a new empirical model and simplified method for predicting cutting rates were proposed through data analysis in relation to operation time and rock strength, and compared with those of the conventional model from the manufacturer. The results show good agreement for high strength range upper 80 MPa of uniaxial compressive strength.

고관절 주위 골절환자에서 술 전 색 도플러 초음파를 이용하여 진단한 심부 정맥 혈전의 빈도

정재훈,이경재,민병우,손은석,구태원,Jung, Jae-Hoon,Lee, Kyung-Jae,Min, Byung-Woo,Son, Eun-Seok,Koo, Tae-Won 대한정형외과초음파학회 2014 대한정형외과 초음파학회지 Vol.7 No.2

목적: 고관절 주위 골절 환자에서 술 전 색 도플러 초음파 검사를 이용하여 심부 정맥 혈전증을 진단하고 그 발생 빈도를 알아 보고자 하였다. 대상 및 방법: 2013년 6월부터 2014년 5월까지 본원에 내원한 고관절 주위 골절 환자 중 이전에 심부 정맥 혈전의 과거력이 없으며 술 전 색 도플러 초음파 검사에 동의한 환자 27예를 대상으로 하였으며 남자가 8예, 여자가 19예이었다. 평균 연령은 74.3세(41-87)였다. 고관절 주위 골절의 진단명은 대퇴 경부 골절 15예, 대퇴 전자간 골절 11예, 비구 골절이 1예였다. 모든 수술은 본원 내원 후 48시간 이내에 시행하는 것을 원칙으로 하였으며 내원 24시간 이내에 색 도플러 초음파 검사를 시행하였다. 결과: 심부 정맥 혈전은 총 6예(22.2%)에서 발견되었다. 이중 2예(7.4%)는 근위 심부 정맥 혈전이었고 4예(14.8%)는 원위 심부 정맥 혈전이었다. 심부 정맥 혈전 발생 군이 평균 79세(75-87), 발생하지 않은 환자 군이 평균 72세(65-86)로 유의하게 많았다(p=0.038). 결론: 고관절 주위 골절 환자에게 수술 이전 실시한 색 도플러 초음파 검사상 22.2%로 비교적 높은 빈도로 심부 정맥 혈전이 발견되었다. 고관절 주위 골절 환자에서 술 전 심부 정맥 혈전증에 대한 보다 적극적인 검사가 필요할 것으로 사료된다. Purpose: To evaluate the incidence of deep vein thrombosis (DVT) before hip fracture by duplex color Doppler ultrasonography. Materials and Methods: From June 2013 to May 2014, 27 patients who had agreed to perform color Doppler ultrasonography before hip fracture surgery were evaluated for the incidence of DVT. Patients who had history of DVT were excluded. Five patients were men and 19 patients were women. The mean age was 74.3 years old (41-87). There were 15 cases of femoral neck fracture, 11 cases of intertrochanteric fractures and one case of acetabular fracture. Surgical intervention underwent within 48 hours from admission and duplex color Doppler ultrasonography was carried out at the day of admission. Results: DVT occurred in six cases (22.2%). Four cases (14.8%) occurred in proximal deep vein and two cases (7.4%) occurred in distal deep vein. The mean period of immobilization was longer in patients who had DVT. But there was no significant difference. The mean age was 79 years old (75-87) in patients who had DVT and 72 years old (65-86) in patients who had not. There was significant difference (p=0.038). Conclusion: The incidence of DVT which was diagnosed by duplex color Doppler ultrasonography before hip fracture surgery was relatively high (22.2%). So it is necessary to undergo duplex color Doppler ultrasonography more aggressively to rule out DVT before hip fracture surgery.

거대 분자운의 원적외선 특성

정재훈,김현구,김봉규,Jung, Jae-Hoon,Kim, Hyun-Goo,Kim, Bong-Gyu 한국천문학회 2006 天文學論叢 Vol.21 No.2

Infrared color-color diagram of 10 giant molecular clouds are examined to explore the dust property from the COBE Diffuse Infrared Background Experiment of the 100, 140, and $240{\mu}m$ emission. Four of them, Taurus, Mon OB1, Gem OB1, and Chameleon, show the anti-correlation in $R_{100/140}-R_{140/240}$ plot and the horizontal distribution in $R_{100/240}-R_{140/240}$ plot, which disagree with those of theoretical calculation. These could be explained by the depletion of $100{\mu}m$ and the excess of $140{\mu}m$ emission, though no existing dust model could support them. Mean color temperature of the anti-correlation region appears to be lower than that of the linear region, whose temperatures are 15.3, 17.0 K, respectively. And the linear region shows large dispersion in the plot of intensity relation. Both imply that a star formation would be more active, but not homogeneous, in the linear region compared to the anti-correlation region.

Arrayed Waveguide Grating의 스펙트럼해석

정재훈,Jung, Jae-Hoon 한국전기전자학회 2004 전기전자학회논문지 Vol.8 No.1

Arrayed waveguide grating의 스펙트럼을 해석하기 위해 Fresnel Kirchhoff diffraction 식과 Fraunhofer diffraction 근사식을 이용하여 실제로 제작되는 16채널 및 40채널의 arrayed waveguide grating에 대해 적용해 보았으며 Fraunhofer diffraction 근사식을 적용할 때 생기는 문제점을 모델별로 도출하였고 그 오차를 실제의 공정오차와 비교하였다. We performed the spectrum analysis of arrayed waveguide grating using Fresnel Kirchhoff diffraction formula and its approximated Fraunhofer diffraction equation and applied both methods to 16 channel and 40 channel models. We presented the spectra and found out the limitations of Fraunhofer diffraction in analysis of arrayed waveguide grating and compared the errors coming from Fraunhofer diffraction approximation and due to imperfection during the fabrication process.

플라스틱 기판을 이용한 고분자 청색 유기발광다이오드의 발광 특성

정재훈,문대규,Jung, Jae-Hoon,Moon, Dae-Gyu 한국전기전자재료학회 2013 전기전자재료학회논문지 Vol.26 No.9

We have fabricated blue phosphorescent organic light-emitting devices (OLEDs) on a plastic substrate. The solution coated poly (9-vinylcarbazole) (PVK) host doped with Bis (3,5-difluoro-2-(2-pyridyl)phenyl_(2-carboxypyridyl)irdium(III) (FIrPic) guest molecules was used as an hole transporting emission layer. The device structure was ITO/PVK:FIrpic (50 nm, xwt%)/TAZ 50 nm)/LiF (0.5 nm)/Al (100 nm). The concentration of FIrpic molecule was varied from 1 wt% to 10 wt%. The OLED on plastic substrate exhibited maximum current efficiency of 18 cd/A with 5 wt% FIrpic molecules were doped into the PVK layer.

한국 성인에서 주관적 인지저하를 동반한 우울증의 특성과 삶의 질 : 제 7기 국민건강영양조사를 중심으로

정재훈,김성진,정도운,문정준,전동욱,김연수,최현석,이민주,전경수,Jeong, Jae-Hoon,Kim, Sung-Jin,Jung, Do-Un,Moon, Jung-Joon,Jeon, Dong-Wook,Kim, Yeon-Sue,Choi, Hyeon-Seok,Lee, Min-Joo,Jeon, Gyeong-Su 한국정신신체의학회 2021 정신신체의학 Vol.29 No.1

Objectives : This study aimed to investigate quality of life, severity of depression, suicidality, subjective health and subjective stress of depression with subjective cognitive decline in Korean adults. Methods : We used the 7th KNHANES data to enroll 415 participants with a score of 10 or higher on Patient Health Questionnaire-9 (PHQ-9), aged 20-64. Depression was divided into two groups based on the presence/absence of subjective cognitive decline. Demographic and psychological characteristics were compared between two groups. Correlation analysis of subjective cognitive decline, quality of life, depression, suicidal idea was carried out. To detect which variables influenced quality of life, a multiple regression analysis was carried out. Results : Among the 415 participants, 98 had depression with subjective cognitive decline. We identified significant differences in age, marital status, education, employment between the two groups. After adjusting for these variables, depression with subjective cognitive decline had lower EuroQol-5D index scores, more severe depressive symptoms without cognition and worse subjective health than depression without cognitive decline. There was a significant correlation between subjective cognitive decline and quality of life (r=-0.236, p<0.001), suicidal idea (r=0.182, p<0.001), depression score without cognition (r=0.108, p=0.028). Through multiple regression analysis, subjective cognitive decline was predictor of reduced quality of life (β=-0.178, p<0.001). Conclusions : Depression with subjective cognitive decline has poor quality of life and severe depression. Cognitive decline should be considered to improve treatment result in depression. 연구목적 국내의 성인을 대상으로 주관적 인지 저하를 동반한 우울증에서 삶의 질, 우울의 심각도, 자살 관련 특성, 주관적 건강 상태 및 스트레스 인지에 대해 조사하고자 하였다. 방 법 국민건강영양조사 제 7기 자료를 이용하여 Patient Health Questionnaire (PHQ-9)에서 10점 이상인 인구 415명을 대상으로 하였다. 주관적 인지 저하 유무에 따라 두 군의 특성 차이를 비교했다. 주관적 인지 저하와 삶의 질, 우울, 자살사고의 상관성을 보기 위해 상관분석 및 회귀 분석을 실시했다. 결 과 주관적 인지 저하를 동반한 우울증 집단이 삶의 질과 주관적 건강이 더 좋지 않았고 우울의 심각도가 심했다. 주관적 인지 저하와 삶의 질은 음의 상관관계, 자살사고와 우울은 양의 상관관계를 보였다. 회귀 분석을 통해 주관적 인지 저하가 삶의 질에 부정적 영향을 미치는 것을 확인했다. 결 론 주관적 인지 저하를 동반한 우울증은 삶의 질을 저해하고 우울의 심각도가 심하며 삶의 질, 자살사고 및 우울을 악화시키는 것으로 확인되었다.

상악전치부 심미에 대한 인식도 평가

정재훈,오상천,Jung Jae-Hoon,Oh Sang-Chun 대한치과보철학회 2003 대한치과보철학회지 Vol.41 No.5

Statement of problem : The beauty has a little different meaning according to a time, culture, and nation. Purpose : This study was undertaken to determine the Korean perception of the altered upper anterior dental esthetics including the lack of symmetry, the midline deviation, the gingival exposure, the inclination of incisal plane, the type of incisal plane, and the type of gingival line. Material and Method : 670 subjects were participated in this survey. A questionnaire accompanied by 12 sets of computer-manipulated images using 3D MAX 4.2 software was used to record the ranking of the geometric preference related to the anterior esthetic discrepancies in three or four degrees of alteration. The statistical significance of the differences between the groups was determined by a one-way ANOVA and a t-test. Results : The results obtained were as follows: 1) The Korean perception of the anterior dental esthetics according to the subjects' occupation, sex, and age was most affected by occupation. 2) The masked image emphasizing the dentition and lips appeared stranger than the non-masked image at the same alteration. 3) The lack of symmetry, which was expressed as a unilateral discoloration of the tooth, showed incongruity in any teeth of the anterior dentition. The incongruity was more severe as the degree occurred closer to the midline. 4) The deviation of midline was showed more severe strangeness as the degree of deviation increased. However, more than half of the subjects did not perceive a deviation of 5mm. 5) During smiling, the exposure of the upper gingiva showed more severe incongruity as the degree of gingival exposure increased. 77% of the subjects perceived strangeness at the gingival exposure of 4.5mm. 6) The inclination of the incisal plane appeared stranger as the degree of inclination increased. 62% of subjects perceived strangeness at the $7.5^{\circ}$ inclination of the incisal plane. 7) The type of incisal plane showed increasing strangeness in the order of convex/downward, straight/horizontal, and concave/upward. 80% of subjects perceived strangeness at concave/upward. 8) The type of gingival line was showed increasing incongruity in the order of the same, a little above, and a little under the zenith of the lateral incisor to the line joining the zenith of the central incisor and the canine. However, less than half the subjects did not perceive strangeness at any alteration of the gingival line. Conclusion : The Korean perception of the upper anterior dental esthetics was different to the westerner's perception in the some respects.

혁신형 중소기업의 조직혁신역량이 기업의 수출성과에 미치는 영향

정재훈,오가영,Jung, Jae Hoon,Oh, Ka Young 강원대학교 경영경제연구소 2022 Asia-Pacific Journal of Business Vol.13 No.3

Purpose - This study investigate the effect of innovative capacity on corporate export performance and moderating flexibility. Design/methodology/approach - For this, hypotheses were established by reviewing previous studies and an empirical analysis was conducted for testing. Using SPSS 22.0, a frequency analysis of related variables was conducted. Through an exploratory factor analysis, validity and reliability tests of measuring tools were conducted and a descriptive statistics was analyzed for collected data result and hypotheses testing. Findings - Finally, with a verified model, the hypotheses and the moderating effects were tested. The results are as follows; The innovationa capacities have a positive effect on export performance and flexibility However, the flexbilitiy was not moderator in the relationship between innovative capacity and export performance. Research implications or Originality - According to the results above, this study presents directions to improve export performance of technological innovative type SMEs. The innovative capabilities, marketing capacity, organization innovative capacity and process innovative capactity, has an positive effect on

안와 상벽 골절과 광대뼈 골절의 임상 양상과 치료 및 동반된 안과적 진단

정재훈,이화,이종미,백세현,Jae Hoon Jung,Hwa Lee,Jongmi Lee,Sehyun Baek 대한안과학회 2012 대한안과학회지 Vol.53 No.4

Purpose: To investigate the clinical manifestations, management, and ophthalmologic complications of orbital roof fractures and zygoma fractures. Methods: A retrospective survey of 119 patients who visited Korea University Medical Center from June 2009 to June 2010 was performed. The sex, age, causes, fracture characteristics, neurologic injury, ocular injury, and combined facial bone fractures of patients who were diagnosed with orbital roof fracture and zygoma fracture were statistically analyzed. Results: The mean age of patients with orbital roof fracture was 33.0 years old. The most common cause of orbital roof fracture was traffic accident (36.1%) with 6 patients receiveing surgical treatement (9.8%). Among the ophthalmologic diagnoses of the patients with orbital roof fracture, traumatic iridocyclitis was the most common (7 eyes) followed by eyeball rupture (2 eyes). The mean age of patients with zygoma fracture was 36.6 years old. The most common cause of zygoma fracture was traffic accident (32.8%), with 51 patients receiving surgical treatement (87.9%). Among the ophthalmologic diagnoses of the patients with zygoma fracture, traumatic iridocyclitis was the most common (6 eyes), followed by commotio retina (4 eyes). Conclusions: The present study regarding clinical characteristics and treatment of orbital roof fracture and zygoma fracture is helpful for ophthalmologists regarding the treatment of accompanying ophthalmologic complications. J Korean Ophthalmol Soc 2012;53(4):577-581

개화기 사과 '후지'와 '홍로'의 품종간 저온 피해율, 호르몬과 유리당 분석

정재훈,한점화,류수현,조정건,이슬기,Jeong, Jae Hoon,Han, Jeom Hwa,Ryu, Suhyun,Cho, Jung Gun,Lee, Seul-Ki 한국생물환경조절학회 2021 생물환경조절학회지 Vol.30 No.4

최근 지구온난화에 의한 이상기상으로 겨울철 한파와 봄철 저온에 의한 농작물 피해가 심각하게 발생하고 있다. 특히 과수의 개화기 저온피해는 꽃눈의 생육단계에 따라 차이가 있으며 발육이 진전될수록 내한성이 약해져 개화 직전부터 낙화 후 1주까지 한계온도가 다르게 발생한다. 따라서 개화기가 빠른 사과 '홍로'가 '후지'보다 피해가 심각한 것이 일반적이나 2020년 4월 저온피해는 개화기가 늦은 '후지'의 피해가 심하게 발생하여그 원인을 분석하고자 본 연구를 수행하였다. 충북 보은군 사과나무 '후지'와 '홍로'를 동시에 재배하는 2농가를 대상으로 품종 간 피해율 실태조사를 실시하였다. 또한 정확한 품종 간 비교 분석을 위하여 생육단계가 동일한 시료를 선택하여 인위적으로 저온처리(-2.0℃, -4.0℃)를 하여 피해 정도를 조사하고, 원인 분석을 위해 조직 내 유리당과 호르몬 함량을 분석하였다. 실태조사 결과 2농가 모두 '후지'가 '홍로'보다 피해율이 높았으며, 특히 B농가(저지대, 평지) '후지'의 경우 피해율이 60.5%로 가장 높았다. 또한 동일한 생육단계의 시료를 사용한 인위적 저온 처리 시험결과에서도 '후지'와 '홍로' 품종 간 피해율에 유의한 차이가 있었다. 유리당 함량은 저온 피해율이 낮았던 '홍로'가'후지'보다 높았으며, 호르몬 분석 결과 정상 꽃눈보다 손상된 조직에서 ABA, IAA와 SA 함량이 높게 나타났다. 따라서 본 연구 결과 조직내 유리당 함량이 높으면 저온 피해율이 낮은 것을 확인할 수 있었으며, 특히 저온 피해율은 sorbitol 함량과 부의 상관관계를 이루고 있다. Freezing damage to fruit trees is frequently occurring due to cold in winter and low temperature in spring to abnormal weather caused by global warming. In particular, the freezing injury of deciduous fruit trees is highly dependent on the developmental stages of the flower buds. And the cold resistance is weakened as the growth progresses, so it is most vulnerable period from flowering to petal fall(post-bloom). Therefore, this study was conducted to analyze the cause of the freezing injury caused by severe low temperature to 'Fuji', which has a late flowering period more than 'Hongro' in April 2020. We investigated freezing injury rate in 'Fuji' and 'Hongro' apple trees damaged by natural low temperature at Boeun-gun, Chungbuk province in Korea. In addition, flower buds in the same developmental stage (tight cluster) were treated artificially low temperature to investigate the injury rate for accurate comparative analysis between varieties, and to analyze the soluble sugar and hormone contents in the flower buds. As a result of survey in natural low temperature, 'Fuji' had a higher injury rate than 'Hongro' in both orchards, and in particular, B orchard 'Fuji' had the highest injury rate of 60.5%. Also there were significantly difference in the freezing injury rate between 'Fuji' and 'Hongro' in artificially low temperature treatments. As a result of analyzing the soluble sugar contents in 'Hongro' was higher than 'Fuji'. Also ABA, IAA and SA contents were more increased in the damaged tissue than in the normal flower buds by low temperature treatments. Consequently, it was assumed that the freezing injury was closely related to soluble sugar contents in the flower buds. In particular, the freezing injury rate was negatively correlated with the sorbitol contents.