한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

소의 대동맥 내피세포에서 산화저밀도 지단백에 의한 아포프토시스에 백일해 독소 및 콜레라 독소가 미치는 영향

손호영(Ho Young Son),강성구(Sung Ku Kang),강무일(Moo Il Kang),차봉연(Bong Youn Cha),이광우(Kwang Woo Lee),장상아(Sang Ah Chang),최윤희(Yoon Hee Choi),문성대(Sung Dae Moon),안유배(Yoo Bae Ahn),손현식(Hyun Sik Son),윤건호(Kun Ho Yoon) 대한내과학회 1999 대한내과학회지 Vol.56 No.5

N/A Objectives : Oxidized LDL is thought to play a key role in atherogenesis. Among their wide variety of biological properties, oxidized LDL injures the endothelium as an early event of atherogenesis. However, the mechanisms by which oxidized LDL injures endothelial cells are not definitely known. In order to evaluate the involvement of GTP-binding protein on the mechanism of apoptosis, we studied the effects of pertussis and cholera toxin on oxidized LDL-induced apoptosis in bovine aortic endothelial cells(BAECs). Methods : Oxidized LDL elicited apoptosis in cultured BAECs as shown by characteristic morphological and biochemical changes. Chromatin condensation and nucleus fragmentation were visualized by using fluorescence microscopy of intact cells staining by acridine orange/ ethidium bromide. DNA fragmentation was quantified by an ELISA with specific antibody for bromodeoxyuridine- labelled DNA fragments and confirmed with DNA ladder formation. Results : Studies using a combination of bacterial toxins which change the function of GTP-binding protein suggest that oxidized LDL-induced apoptosis was regulated by GTP-binding protein. Oxidized LDL-induced apoptosis was not changed by pretreatment of BAECs with pertussis toxin. In contrast, pretreatment with cholera toxin completely prevented the oxidized LDL- induced apoptosis. Conclusion : These results show that oxidized LDL induces apoptosis of BAECs and suggest that cholera toxin-sensitive G-proteins are involved in signal transduction of oxidized LDL-induced apoptosis of BAEC.

광조사 강도가 복합레진의 중합반응속도에 미치는 영향에 관한 실시간 체적측정법을 이용한 연구

라성호,이인복,김창근,조병훈,이광원,손호현 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.2

Objectives The aim of this study is to evaluate the effect of light intensity variation on the polymerization rate of composite resin using IB system (the experimental equipment designed by DR. IB Lee) by which real-time volumetric change of composite can be measured. Methods Three commercial composite resins [Z100(Z!), AeliteFil(AF), SureFil(SF)] were photopolymerized with Variable Intensity Polymerizer unit (Bisco, U.S.A.) under the variable light intensity (75/150/225/300/375/450mW^2) during 20 sec. Polymerization shrinkage of samples was detected continuously by IB system during 110 sec and the rate of polymerization shrinkage was obtained by its shrinkage data. Peak time(P.T.) showing the maximum rate of polymerization shrinkage was used to compare the polymerization rate. Results Peak time decreased with increasing light intensity(p<0.05). Maximum rate of polymerization shrinkage increased with increasing light intensity(p<0.05). Statistical analysis revealed a significant positive correlation between peak time and inverse square root of the light intensity (AF:R=0.965, Z1:R=0.974, SF:R=0.927). Statistical analysis revealed a significant negative correlation between the maximum rate of polymerization shrinkage and peak time(AF:R=-0.933, Z1:R=-0.892, SF:R=-0.883), and a significant positive correlation between the maximum rate of polymerization shrinkage and square root of the light intensity(AF:R=0.988, Z1:R=0.974, SF:R=0.946). Discussion and Conclusions The polymerization rate of composite resins used in this study was proportional to the square root of light intensity. Maximum rate of polymerization shrinkage as well as peak time can be used to compare the polymerization rate. Real-time volume method using IB system can be a simple, alternative method to obtain the polymerization rate of composite resins.

레진 침투법 후 인공 법랑질 백색 병소의 색과 경도 변화 비교

김지훈,손호현,장주혜 大韓齒科保存學會 2012 Restorative Dentistry & Endodontics Vol.37 No.2

Objectives: The purpose of this study was to determine the effect of resin infiltration technique on color and surface hardness of white spot lesion (WSL) with various degrees of deminerealization. Meterials and methods: Ten human upper premolars were cut and divided into quarters with a 3 * 4 mm window on the enamel surface. Each specimens were separated into four groups (n = 10) and immersed in demineralization solution to create WSL: control, no treatment (baseline); 12 h, 12 hr demineralization; 24 h, 24 hr demineralization; 48 h, 48 hr demineralization. Resin infiltration was performed to the specimens using Icon (DMG). CIEL*a*b color parameters of the enamel-dentin complex were determined using a spectroradiometer at baseline, after caries formation and after resin infiltration. Surface hardness was measured by Vickers Micro Hardness Tester (Shimadzu, HMV-2). The differences in color and hardness among the groups were analyzed with ANOVA followed by Tukey test. Results: Resin infiltration induced color changes and increased the hardness of demineralized enamel. After resin infiltration, there was no difference in color change (△E*) or microhardness among the groups (p < 0.05). Conclusion: There was no difference in the effect of resin infiltration on color and hardness among groups with different extents of demineralization. (Restor Dent Endod 2012;37(2):90-95)

급성 췌장염으로 발현된 낭성 변화를 이릉킨 종격동 부갑상선 선종 1예

이준호,최영식,박진홍,허갑도,윤설영,최소진,권태헌,이창렬,손성표,박영효 대한내분비학회 1998 Endocrinology and metabolism Vol.13 No.3

Hypercalcemia due to hyperparathyroidism is rarely associated with acute pancreatitis. But, the relationship between hypercalcemia and pancreatitis still remains controvesial. Ectopic parathyroid adenoma with cystic change is one of the rare causes of hyperparathyroidism, and is usually located in neck and mediastinum. We report a case of mediastinal parathyroid adenoma with cystic change associated with acute pancreatitis. A 54-year-old male presented with epigastric pain for 3 days. The serum calcium, phosphate, elastase were 16.8mg/dL, 1.1 mg/dL, 2772.0 ng/mL respectively and his parathyroid hormone level in serum was 651.84 pg/mL. Chest CT showed a mediastinal mass with well defined inhomogenously enhanced density located between SVC and aorta. The patient was diagnosed to hyperparathyroidism with acute pancreatitis due to mediastinal parathyroid adenoma with cystic change, and was surgically removed. The surgical biopsy showed parathyroid adenoma with cystic change. After operation his general condition was improved and serum calcium, phosphate, amylase, lipase level were normalized (J Kor Soc Endocrinol 13:473-479, 1998).

Biotransformation of major ginsenosides in ginsenoside model culture by lactic acid bacteria

Park, Seong-Eun,Na, Chang-Su,Yoo, Seon-A,Seo, Seung-Ho,Son, Hong-Seok The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.1

Background: Some differences have been reported in the biotransformation of ginsenosides, probably due to the types of materials used such as ginseng, enzymes, and microorganisms. Moreover, most microorganisms used for transforming ginsenosides do not meet food-grade standards. We investigated the statistical conversion rate of major ginsenosides in ginsenosides model culture during fermentation by lactic acid bacteria (LAB) to estimate possible pathways. Methods: Ginsenosides standard mix was used as a model culture to facilitate clear identification of the metabolic changes. Changes in eight ginsenosides (Rb1, Rb2, Rc, Rd, Re, Rf, Rg1, and Rg2) during fermentation with six strains of LAB were investigated. Results: In most cases, the residual ginsenoside level decreased by 5.9-36.8% compared with the initial ginsenoside level. Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased during fermentation. By contrast, Rd was maintained or slightly increased after 1 d of fermentation. Rg1 and Rg2 reached their lowest values after 1-2 d of fermentation, and then began to increase gradually. The conversion of Rd, Rg1, and Rg2 into smaller deglycosylated forms was more rapid than that of Rd from Rb1, Rb2, and Rc, as well as that of Rg1 and Rg2 from Re during the first 2 d of fermentation with LAB. Conclusion: Ginsenosides Rb1, Rb2, Rc, and Re continuously decreased, whereas ginsenosides Rd, Rg1, and Rg2 increased after 1-2 d of fermentation. This study may provide new insights into the metabolism of ginsenosides and can clarify the metabolic changes in ginsenosides biotransformed by LAB.

Biomechanical analysis of lumbar decompression surgery in relation to degenerative changes in the lumbar spine – Validated finite element analysis

Li, Quan You,Kim, Ho-Joong,Son, Juhyun,Kang, Kyoung-Tak,Chang, Bong-Soon,Lee, Choon-Ki,Seok, Hyun Sik,Yeom, Jin S. Elsevier 2017 Computers in biology and medicine Vol.89 No.-

<P><B>Abstract</B></P> <P><B>Background</B></P> <P>There are no studies about the biomechanical analysis of lumbar decompression surgery in relation to degenerative changes of the lumbar spine. Therefore, the purpose of this study was to compare, by using finite element (FE) analysis, the biomechanical changes of the lumbar spine in terms of annulus stress and nucleus pressure after two different kinds of lumbar decompression surgery in relation to disc degenerative changes.</P> <P><B>Methods</B></P> <P>The validated intact and degenerated FE models (L2-5) were used in this study. In these two models, two different decompression surgical scenarios at L3-4, including conventional laminectomy (ConLa) and the spinous process osteotomy (SpinO), were simulated. Therefore, a total of six models were simulated. Under preloading, 7.5 Nm moments of flexion, extension, lateral bending, and torsion were imposed. In each model, the maximal von Mises stress on the annulus fibrosus and nucleus pressure at the index segment (L3-4) and adjacent segments (L2-3 and L4-5) were analyzed.</P> <P><B>Results</B></P> <P>The ConLa model and disc degeneration model demonstrated a larger annulus stress at the decompression level (L3-4) under all four moments than were seen in the SpinO model and healthy disc model, respectively. Therefore, the ConLa model with moderate disc degeneration showed the highest annulus stress at the decompression level (L3-4). However, the percent change of annulus stress at L3-4 from the intact model to the matched decompression model was less in the moderate disc degeneration model than in the healthy disc model.</P> <P><B>Conclusions</B></P> <P>Although the ConLa model with moderate disc degeneration showed the highest annulus stress, the degenerative models would be less influenced by the decompression technique.</P>

온도변화에 따른 파이버 브래그 격자 필터의 특성에 관한 연구

손용환(Yong-Hwan Son),이종윤(Jong-Youn Lee),허주옥(Ju-ok Huh),배창환(Chang-Hwan Bae),정진호(Jin-Ho Jung) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.11

In this paper, we present thermal characteristics of a fiber Bragg grating(FBG) filter, including peak reflectivity and FWHM bandwidth by various refractive index change. The reflection spectrum of a FBG filter with refractive index change is affected by its thermal stability.

스마트팜 환경 관리를 위한 계측 시스템

이동형(Dong-Hyung Lee),백창대(Chang-Dae Back),윤현성(Hyeon-Seong Yun),손형민(Hyeong-Min Son),차현석(Hyun-Seok Cha),김남호(Nam-Ho Kim) 한국정보통신학회 2021 한국정보통신학회 종합학술대회 논문집 Vol.25 No.2

정보통신기술이 점차 발전함에 따라 기존의 생산 시스템에 네트워크 및 컴퓨팅 기술을 적용하여 효율적인 생산 환경을 유지하는 연구가 많이 진행되고 있다. 고전적인 제어 시스템과 달리 이러한 스마트 생산 시스템은 생산 환경에 대한 데이터를 실시간으로 수집하여 통계화하고, 그 변화에 따라 유동적으로 작동할 필요가 있다. 본 논문에서는 네트워크 기반의 센서를 통해 실시간으로 데이터를 수집하고, 환경 변화에 효과적으로 대응할 수 있는 계측 시스템을 제시한다. 또한 이를 스마트팜에 적용하여 외부의 환경 변화에 대처하고 효과적인 생산 환경을 유지할 수 있음을 확인하였다. As information and communication technologies develop, many studies are being conducted to maintain an efficient production environment by applying network and computing technologies to existing production systems. Unlike classical control systems, these smart production systems need to collect data about the production environment in real time, and operate fluidly as it changes. In this paper, we present a measurement system that can collect data in real time through network-based sensors and respond effectively to environmental changes. We also proved this smart system can cope with external environmental changes and maintain an effective production environment.

Design of a shape memory composite(SMC) using 4D printing technology

Kang, Minkyu,Pyo, Youngjun,Jang, Joon young,Park, Yunchan,Son, Yeon-Ho,Choi, MyungChan,Ha, Joo wan,Chang, Young-Wook,Lee, Caroline Sunyong Elsevier 2018 Sensors and actuators. A Physical Vol.283 No.-

<P><B>Abstract</B></P> <P>A fused deposition modeling (FDM) tool was used to fabricate a shape memory composite (SMC) that combined a shape memory alloy (SMA) with a shape memory polymer (SMP). The SMA caused a shape memory effect due to a phase change between martensite and austenite phases, in turn due to a temperature change. Also, the SMP had a shape memory effect caused by changes in the proportions of hard and soft segments near the glass transition temperature (T<SUB>g</SUB>). Usually, common SMAs and SMPs are not reversible, so these materials do not go back to their original shapes once they are deformed. In this study, we fabricated 4D printing actuator via reversible SMC actuations using 3D printing technology. Nylon 12 was used as the 3D printing material in filament form. Moreover, the volume fraction of SMA to SMP was varied to find the optimum ratio for good operation cycles. A volume fraction of SMA:SMP of 1:5 showed the largest length change, of 8 mm, and the most rapid response time, of 4 s in overall dimension of 140mm×10mm×1mm (length×width×thickness).Thus, the SMC showed promising results for the application of stents and valve controllers that could be manufactured by 3D printing technology.</P> <P><B>Highlights</B></P> <P> <UL> <LI> An 4D printed SMC actuator was fabricated using SMA and SMP with a FDM 3D printer. </LI> <LI> A volume fraction of SMA:SMP of 1:5 showed the largest length change of 8 mm, and the most rapid response time of 4 s. </LI> <LI> The reversible actuator mechanism explains the SMC actuation via each shape memory effect. </LI> <LI> SMC showed potential application for stents and valve controllers via 3D printing technology to achieve customized designs. </LI> </UL> </P>