Insulation Coating of Fe–Si–Cr Soft Magnetic Powder by Selective Oxidation

Jae‑Young Park,Kwangsuk Park,Bosung Seo,Julien O. Fadonougbo,Tae‑Wook Na,Ki Beom Park,Hyeon‑Tae Im,Nong‑Moon Hwang,Hyung‑Ki Park 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

This study examines the insulation coating technology of Fe–Si–Cr powder via selective oxidation annealing, which oxidizeselements selectively by controlling the oxidation potential. The study calculated the oxidation driving force of Fe, Si, andCr, and conducted a thermodynamic analysis of oxidation and reduction conditions according to temperature and oxidationpotential. Based on the results, a selective oxidation annealing was performed in an atmosphere in which Fe is reduced andonly Si and Cr are selectively oxidized. The oxidation potential was controlled through the partial pressure ratio of hydrogenand water vapor. The XPS analysis results confirmed that a Si and Cr complex oxide layer formed on the powder surfaceafter the selective oxidation annealing. Afterward, withstanding voltages were analyzed to evaluate the insulation property. Then, the withstanding voltage of the powder applying the selective oxidation annealing increased significantly comparedto that of the initial powder. Further analysis showed that the powder annealed in an air atmosphere had a significantly lowersaturation magnetic flux density than the initial powder, while the powder applying the selective oxidation annealing hadonly a slightly reduced saturation magnetic flux density.

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

콩의 개화기전후 공급과 수용부위의 무기영양성분함량 및 흡수량에 대한 질소의 효과

박재홍,송범헌,이철원,손석용,김홍식,박상일 忠北大學校 農業科學硏究所 2002 農業科學硏究 Vol.19 No.-

This study was conducted to examine the nitrogen effects on the uptaken amounts and utilization of mineral nutrients between source and sink tissues at major growth stages before and after the flowering stage with different nitrogen levels Hwangkeum cultivar(Glycine max L Mereill) was cultivated under five different mtrogen levels, 0, 2, 4, 6, 8 N kg/10a Comparing contents of total-N with different plant tissues at major growth stages before and after the flowering, total-N contents of leaves was gradually decreased from the flowering to the beginning maturity, while it of pod was continuously increased from the full seed to the beginning maturity Total-N content was higher in the treatment of 4 N Kg/10a that those of others The uptaken amount of N determined with different growth stage was rapidly increased maturity Higher proportion of uptaken N were into the leaves at the full seed stage, and they were transported from the leaves into pod at the beginning maturity stage Comparing major mineral elements of the leaves and the pod with different N leaves, in case of the leaves, the content of Fe, Mn, and Zn was decreased throughout the growth stages, whereas the content of Ca and Mg was decreased from the flowering to the full seed and then it was increased after the full seed stage In case of pod, the content of K, Fe, Mn, Zn, and Na was decreased from the flowering to the beginning maturity, while contest of Mg was increased.

폐구리염화물용액의 분무열분해반응에 의한 생성분말의 특성에 관한 연구

박희범,최재권,한진아,유재근 호서대학교 반도체제조장비국산화연구센터 2001 반도체장비학술심포지움 Vol.2001 No.-

본 연구의 목적은 폐 구리염화물 용액을 원료로 사용하여 분무열분해 공정에 의해 평균입도가 1 ㎛ 이하이며 입도분포가 균일하고 치밀한 조직을 나타내는 미립의 구리산화물 분말을 제조하는데 있다.또한 본 연구에서는 분무열분해 공정에 의해 생성되는 분말의 특성에 영향을 미치는 반응 온도, 원료용액의 유입속도, 분위기기체 및 공기의 유입속도, nozzle tip 크기 및 원료용액의 농도 등의 반응인자들의 영향을 검토하였다.

콩의 개화기 전후 공급과 수용부위의 생장반응과 수량에 대한 질소의 효과

박재홍,송범헌,이철원,손석용,김홍식,박상일 忠北大學校 農業科學硏究所 2002 農業科學硏究 Vol.19 No.-

This study was conducted to examine the nitrogen effects on the growth responses, the nodulation, and the distribution of dry weight of plant tissues at major growth stages before and after the flowering stage, and to evaluate the yield components and yields with different nitrogen levels. Hwangkeum cultivar(Glycine max L mereill) was cultivated under five different nitrogen levels, 0, 2, 4, 6, 8, N Kg/10a. Stem length and branching number, which were investigated with different N levels at major growth stages, were rapidly increased for 14days for before and after the flowering stage compared to the other growth stages. They were clearly higher with treatment of 2 and 4 N kg/10a than those of other N treatments. Pod number was slightly increased from the flowering to beginning maturity. It was the highest in the treatment of 2 N Kg/10a. Comparing grain number per pod with different N levels, two grains per pod was much higher in all N treatments except for the treatment of 6 N Kg/10a. Dry weight of shoot(including leaf, stem, and pod) was rapidly increased from the flowering stage to the full seed stage and then gradually increased after the full seed stage, whereas the dry weight of root(including the nodule and root) was rapidly increased until to full pod stage and then linearly decreased from the full pod stage until the beginning maturity stage. Comparing dry weight with different N levels, the dry weight of shoot was the highest in the treatment of 4 N Kg/10a, while it of root was the highest in the treatment of 2N Kg/10a. The dry weight of nodule was the highest, 13.1 Kg/10a, at full pod stage. Comparing the dry weight of nodule with different N levels, it was increased to the application amount of 4 N Kg/10a and then clearly decreased with more application amount of N than 4 Kg/10a. The yield components which were mostly affected to the yield were pod number per plant and grain number per plant. They were 57.5 and 106.1, respectively, with treatment of 4 N Kg/10a, which showed the highest yield, about 266 Kg/10a. Comparing yield index with different N levels to the control, the yields with treatment of 2 and 4 Kg/10a were increased to 21% and 34%, respectively.

산업용 로울러기의 협착재해 감소방안

박재범,강동규,김두현 한국안전학회 2003 한국안전학회지 Vol.18 No.2

The roller machines installed in the industrial field are operated under hazardous conditions due to no safety devices available, human error during operation, defective safety devices, and inadequate regulation even in case that safety devices are provided. Up to now, most roller machines installed in domestic field are provides with band breaking system as a safety device. In this study, the emergency stop distance is measured within the limit of domestic regulation but violates a foreign regulation(EN1417). Consequently, it is concluded that the roller machines with a band breaking system have high possibility of death or serious injury of the operator and the system should be improved with the introduction of additional safety devices. This thesis suggests the safety measures suitable for the roller machines with different drive systems based on the experiment results. The use of the newly developed safety system has been tested in many cases.

한 자동차 회사의 남성 사무직 근로자에서 직무스트레스와 우울, 불안 및 스트레스 증상과의 관련성

박규철,이경종,박재범,민경복,이규원 大韓産業醫學會 2008 대한직업환경의학회지 Vol.20 No.3

목적: 직무스트레스와 관련성이 있는 우울증,불안 장애 등의 정신과적 질병이 증가하고 있는 상황에서 한 자동차 회사의 남성 사무직 근로자를 대상으로 우울,불안 및 스트레스 증상의 수준을 파악하고 직무스트레스와 우울,불안,스트레스 증상과의 관련성을 살펴보고자 하였다. 방법: 연구 대상자 286명을 설문조사하였다. 직무스트레스 수준과 우울,불안,스트레스 증상을 평가하기 위해 한국인 직무스트레스 측정도구(Korean Occupational Stress Scale; KOSS)와 우울,불안,스트레스 측정도구(Depression Anxiety Stress Scale; DASS)를 사용 하였다. 설문지의 신뢰도와 타당도를 평가하였고 로지스틱 회귀분석을 시행하여 한국인 직무스트레스 측정도구의 8개 영역에 걸쳐 우울,불안 및 스트레스 증상과의 관련성을 살펴보았다. 결과: 연구 대상자에서 우울,불안 및 스트레스 증상이 있는 경우는 각각 57.7%,37.7%, 42.2%였으며,심각 하거나 매우 심각한 우울,불안 및 스트레스 증상을 보이는 경우도 각각 19.6%, 4.8%,8.0%로 조사되었다. 직무스트레스의 총점수가 높은 군에서 우울,불안 및 스트 레스 증상의 발생 비차비는 각각 4.93(95% C.I. = 2.38∼10.24),2.70(95% C.I.=1.58∼5.11). 3.53 (95% C.I.=1.90∼6.56)이었다. 직무스트레스 요인 중 조직체계가 우울 증상의 발생과 관련성이 가장 높았으며 (OR=4.83, 95% C.I.=2.43∼9.58), 직무요구도는 불안 및 스트레스 증상의 발생과 관련성이 높았다(OR=3.21, 95% C.I.=1.77-5.85; OR=4.66, 95% C.I.=2.53∼8.58). 결론: 자동차 회사의 남성 사무직 근로자에서 직무스트레스가 높은 군이 낮은 군에 비해서 우울,불안 및 스트레스 증상이 발생하는 경우가 많았다. 직무요구도와 조직 체계에 대한 개선을 통해 우울,불안 및 스트레스 증상의 발생을 감소시킬 필요가 있다. Objectives: To investigate the relationship between occupational stress and depression, anxiety, and stress symptoms among white-collar male workers in an automotive company. Methods: A cross-sectional study involving 286 white-collar male workers was conducted with the Korean Occupational Stress Scales (KOSS) and Depression Anxiety Stress Scales (DASS) questionnaire. Results: According to the DASS cut-off value (≥78 percentile scores), the prevalence of depression, anxiety and stress system was 57.7%, 37.7% and 42.2%, respectively. By logistic regression analysis, organizational system was the factor most strongly associated with depression (OR=4.83, 95% C.I.=2.43-9.58), while job demand was strongly associated with anxiety (OR=3.21, 95% C.I.= 1.77-5.85) and stress (OR=4.66, 95% C.I.=2.53-8.58). Conclusions: Occupational stress was positively associated with depression, anxiety, and stress symptoms among white-collar male workers in an automotive company. A prospective study is warranted to delineate the causal relationships between job stress and psychiatric disorders.

척추손상 쥐의 지방유래 줄기세포와 미노사이클린의 운동기능 회복효과

장재혁,고현윤,차영선,박형욱,신용범,손현주 부산대학교 병원 암연구소 2009 부산대병원학술지 Vol.- No.25

fmGA를 이용한 하수관거정비 최적화 모델

류재나,기범준,박규홍,이차돈 대한상하수도학회 2004 상하수도학회지 Vol.18 No.2

A long-term sewer rehabilitation project consuming an enormous budget needs to be conducted systematically using an optimization skill. The optimal budgeting and ordering of priority for sewer rehabilitation projects are very important with respect to the effectiveness of investment. In this study, the sewer rehabilitation optimization model using fast-messy genetic algorithm is developed to suggest a schedule for optimal sewer rehabilitation in a subcatchment area by modifying the existing GOOSER model having been developed using simple genetic algorithm. The sewer rehabilitation optimization model using fast-messy genetic algorithm can improve the speed converging to the optimal solution relative to GOOSE , suggesting that it is more advantageous to the sewer rehabilitation in a larger-scale subcatchment area than GOOSER .

서울의 PPNG 발생 빈도(1991-1992)

김재홍,윤기범,박평원,김영진,전경민,김영태,김중환,곽호,구상완,송민석,유옥,지혜구,김동원,문상은,박영립,정승호,성범진,성순제,엄주용,황정열,이기홍,이주협,전태진 대한화학요법학회 1994 대한화학요법학회지 Vol.12 No.1

The prevalence of PPNG among pretreated gonorrhea cases isolated at the STD clinic of Choong-Ku Public Health Center in Seoul has been studied and reported annually since 1981. In 1991, 123 strains of N.gonorrhoeae were isolated, among which 58(47.1%) were PPNG. In 1992, 98 starains of N.gonorrhoeae were isolated, among which 51(52.0%) were PPNG. In all, 109(49.3%) strains were found to be PPNG among 221 strains isolated between 1991-1992. The prevalence of PPNG in Seoul showed increased tendency till 1989, thereafter, it has been stationary or slightly decreasing.