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.

苦汁으로 부터 炭酸마그네슘과 酸化마그네슘의 最適合成條件에 關한 硏究

鄭東燻,辛宗根,申和雨 圓光大學校 1989 論文集 Vol.23 No.2

고즙과 탄산나트륨을 원료로 1)반응액의 온도, 2)반응액의 농도, 3)혼합비율(〔Bittern〕/〔Na₂CO₃〕), 4)작용시간 및 5)건조온도를 합성요인으로 하여 Box-Wilson 실험계획법에 의해 탄산마그네슘의 최적합성조건을 추구하고 그 중 우수제품에 대해 D.S.C.를 측정하여 이를 기준으로 하소시켜 산화마그네슘을 제조하여 용적시험, 제산도시험 및 광학현미경사진을 관찰한 결과 1. 탄산마그네슘의 최적합성조건의 범위는 ①반응액의 온도범위는 50∼70℃ ②반응액의 농도범위는 고즙은 37.3∼38.1%, 탄산나트륨은 9.9∼10.3%, ③혼합비율(〔Bittern〕/〔Na₂CO₃〕)의 범위는 1.485∼1.503, ④작용시간의 범위는 10∼12분, ⑤건조온도의 범위는 73∼83℃이다. 2. 시료탄산마그네슘의 D.S.C.측정결과 75℃정도에서 결정수의 이탈로 보이는 흡열Peak를 나타냈고, 290℃정도에서 구조수의 이탈로 생각되는 흡열Peak를 나타냈으며, 408℃정도에서 탄산깨스의 이탈로 생각되는 흡열Peak를 나타냈다. 3. 탄산마그네슘의 하소온도는 500∼600℃가 적당하겠으며, 용적시험결과는 모두 경질품이었고, 시판품보다 모두 용적시험치가 큰 결과를 나타냈다. 4. 제산도시험의 결과는 시판품의 제산능보다 모두 크며 광학현미경사진에 의한 관찰을 하였다. Optimal Synthesis Condition of Magnesium Carbonate were investigated from the viewpoint of bulkiness according to a randomized complete block design proposed by G.E.P. Box and K.B. Wilson. Bittern and Sodium Carbonate were utilized as reactants in order to prepare Magnesium Carbonate. It was found that optimum temperature range of reactant solutions was 50∼70℃ and the optimum concentration range of the reactant solutions was 37.3∼38.1%(Bittern), 9.9∼10.3%(Sodium Carbonate), on the viewpoint of bulkiness. The optimum mole ratio of Bittern to Sodium Carbonate was in the range of 1.485∼1.503and the optimum reacting time range was 10∼12minutes. The optimum drying temperature range was 73∼83℃. Magnesium Oxide comes two types of granules when prepared by calcination of Magnesium Carbonate. The outcome of D.S.C. indicated a desolvation of Magnesium Carbonate occurred at about 75℃. The dehydration of the compound ceased at about 290℃ and the decarboxylation ceased at about 408℃. The physical and chemical properties of Magnesium Oxide as medicine were studied by use of Volume Test, Optical microscopic photographs and Acid Consuming Capacity measurments.

전문가 시스템과 유한요소법에 의한 열간단조의 공정설계

정영철,이동근,박종진 弘益大學校 科學技術硏究所 1999 科學技術硏究論文集 Vol.10 No.1

In general, a forging product is produced through buster, blocker and finisher processes. The blocker, a transient shape between the buster and the finisher, is to ease the metal flow in the finisher dies. In general, as the finisher shape becomes complicated, the blocker design becomes quite difficult. In the present study, an expert system is developed for the blocker die design of axisymmetric hot steel forging. It is a rule based system written in Fortran and AutoLISP, operating on a personal computer. In this paper, the major rules considered in the system are summarized and several blockers designed by the system are discussed with results of rigid viscoplastic finite element analysis.

벡터제어 유도전동기 구동 시스템의 전류제어기 설계

鄭鍾鎭,金興根 경북대학교 산업기술연구소 1994 産業技術硏究誌 Vol.22 No.-

Characteristics of current controllers used for vector controlled induction motor drive system are presented in this paper. Simulation is performed on each different regulators, i.e., hysteresis controller, stator coordinate ramp comparison controller, synchronously rotating coordinate ramp comparison controller. Hysteresis controller showed that actual current error was twice as large as hysteresis band and stator coordinate ramp comparison controller showed phase delay and steady state error. Synchronously rotating coordinate ramp comparison controller showed that steady state error and phase delay were eliminated. On the whole, synchronously rotating coordinate ramp comparison controller is most preferable to CRPWM inverter in view of the dynamic and steady state response. The system transient behavior is very good, especially regarding to the transient response of flux and torque current component.

PWR에 使用되는 우라늄의 精製 및 濃縮에 關한 硏究(Ⅰ) : 國內産 우라늄 鑛石에서 黃酸浸出과 溶媒抽出에 依한 우라늄精製 Uranium concentration from the Domestic Uranium ores by Sulphuric Leaching and Solvent Extraction

金鍾一,朴永錫,丁梧鎭,李秀一,金熙峰,裵相龍,秋相根 조선대학교 동력자원연구소 1986 動力資源硏究所誌 Vol.8 No.2

This research was undertaken to study the mineralogy, and the optimum conditions for uranium leaching and extraction from the Okchon system graphite ores in the Kumsan areas. A research has been needed to study the refining process for the effective leaching and extraction from uranium ores in the Kumsan area which has more uranium deposits than any other area. By the mineralogical study with the powder X-ray diffraction method, primary uranium minerals are uraninite, brannerite, coffinite etc. and secondary uranium minerals are uranocircite, niobium uranium oxide, carnotite, toberite etc. has developed in the studied area uranium ores. The volumetric ratio of the primary and the secondary uranium minerals are approximatly 1 : 5. In this experiment, the uranium-bearing graphite in the Kumsan area was milled with a jaw crusher and ballmill. This milled uranium-bearing graphite was leached by sulfuric acid and from this sulfuric acid-leaching solution, uranium was extracted by Amberlite LA-1 in kerosene. The results are as follows: (1) The optimum results in the leaching process are : acidity pH = 1.0, temperature : 25.0℃, particle size : -80+120 mesh, leaching time : 24 hours, pulp density : 50% solid (2) A good pH range for uranium extraction was between 0.8 and 1.3. (3) The uranium distribution coefficient increases in direct proportional to the concentration of the Amberlite LA-1 as extractive agent. (4) The optimum time at 200rpm was 15 minutes.

만성 재발성 소아 흉통의 원인 질환과 임상양상

최은정,이은아,이창우,최두영,오연균,김종덕,윤향석 대한소아과학회 2004 小兒科 Vol.47 No.6

Aprotinin의 체외순환에 따른 출혈억제효과

이정은,전대근,김종렬 충남대학교 의과대학 지역사회의학연구소 1992 충남의대잡지 Vol.19 No.2

CPB(cardiopulmonary bypass) is a very complex process ad activated many humoral system which include the coagulation system, firbrinolytic system, kallikrein system, and the complement system, are probably all very important and closely interrelated. It has profound effects the number and especially function of platelets because of contact between blood and gaseous or synthetic solid surface during CPB. These changes increase blood loss after cardiac operations and may transfuse a large amounts of banked blood inevitably which may cause very serious complications including hepatitis and AIDS, etc. Aprotinin is a proteolytic enzyme inhibitor and depress the activation of fibrinolytic system via a powerful antiplasmin activity and may preserve von Willebrand platelet interaction. Two groups of patients were prospectively studied to evaluate the hemostatic effects of high dose aporotinin in open heart operation, first group patients(n=10), at the start of anesthesia 2,000,000 kallikrein inactivator units(KIU) of aprotinin was infused over 20 to 30 minutes. Subsequently, 500,000 KIU/h aprotinin was given untill the end of operation. Additionally, 1,000,000 KIU of aprotinin was in the priming solution of the extracorporeal circuit. Second group patients(n=10) served as controls. The results were as follows, 1. The decrease of hemoglobin and serum protein following CPB was reduced significantly(p<0.05) in aprotinin group. 2. The decrease of platelet number and increase of bleeding time following CPB were reduced in aprotinin group. 3. The intraoperative and postoperative blood loss and the amounts of transfusion of banked blood were reduced significantly(p<0.05) in aprotinin group. In the conclusion, we believe that the use of high dose aprotinin decreases blood loss and reduced the need for banked blood in cardiac patients.

1997년 대청호 藍藻類 水華의 특성

이정호,박종근 大邱大學校附設 基礎科學硏究所 2000 基礎科學硏究 Vol.16 No.2

To investigate dynamic characteristics of cyanobacterial bloom in Daechung dam reservoir, located in Taejon city, algal samples were collected in three sampling stations every week from June from August, 1997. Environmental factors of pH, secchi depth, DO and water temperature were changed irregularly by frequent heavy rainfall for the studying times. A total 78 phytoplankton taxa, composed of 47.8% of Chlorophyceae, 26.9% of Bacillariophyceae, 19.2% of Cyanophyceae and others were collected. Phytoplankton standing crops were changed irregularly without any distinct features according to sampling stations and times. Dominant species were Microcystis and Anabaena taxa in all sampling stations. Especially the bloom has been coused by both Anabaena spiroides var. crassa and Microcystis taxa, mainly M. aeruginosa. Being a physical stability of water column continuously prologed.

남강댐저수지의 식물플랑크톤 군집 동태

이정호,박종근 大邱大學校附設 基礎科學硏究所 2000 基礎科學硏究 Vol.16 No.2

A seasonal dynamics of phytoplankton community in Namgang dam reservoir was studied on March, May, August and October in 1998. Total 94 taxa including 13 unidentified taxa were recorded, which were classified into 77 species and 4 varieties belonging to 57 genera. The maximum of phytoplankton standing crops was 4,338 cells/ml- at st. 3 on October. Diatoms of Aulacoseira distans var. alpigena and A. ambigua were dominant on March and May when water temperature was below 23℃. However, their dominance shifed to green algae of Pandorina morum and blue green algae of Microcystis aeruginosa on August with water temperature greater than 23℃. In this study the algal bloom was not observed in the reservoir on the basis of the standing crops of phytoplankton.

범게, Orithyia sinica 유생의 생존과 성장에 미치는 암모니아와 아질산의 영향

구자근,김종만,장차환,지정훈,강주찬 한국어병학회 2004 한국어병학회지 Vol.17 No.1

범게, Orithyia sinica 유생을 대상으로 암모니아와 아질산에 대한 생존 및 성장에 관한 실험을 실시하였다. 암모니아 노출 실험구에서 zoea기 유생은 노출 20일후, 대조구가 80%의 생존율을 나타내었지만 10㎎/L 이상의 실험구에서는 37-45%의 생존율을 나타내었고, megalopa기 유생에서도 유사한 경향을 나타내었다. 암모니아가 범게 유생의 성장에 미치는 영향을 조사한 결과, zoea기 유생은 20㎎/L 이상의 농도에서 megaloparl 유생은 50㎎/L 이상의 농도에서 유의한 차이를 나타내었다. (P<0.05). 아질산 노출 실험에서는 zoea기 유생과 meglaopa기 유생에서 농도와 노출기간에 비례하여 생존율이 감소하였으며, 특히 150㎎/L 이상의 아질산 농도에 노출된 zoea기 유생가 megalopa기 유생은 대조구와 비교하여 유의한 성장 지연을 나타내었다(P<0.05). This study investigates the influence of waterborne ammonia and nitrite on the zoea and megalopa stage larvae of tiger crab, Orithyiu sinicu under laboratory condition, focusing on the effects on survival and growth as deleterious responses of toxicant. Survival rate of zoea stage larvae exposed to control levels, and to 5, 10,20 and 50 ㎎/L total ammonia-N, using a continuous flow system for 20 days was 80, 77, 45, 40 and 37%, respectively. Growth rate of zoea stage larvae exposed to 20 and 50 ㎎/L total ammonia was significantly lower than in controls after 20 days (P< 0.05). Survival rate and growth rate of megalopa stage larvae exposed to ammonia also decreased at greater than 10 and 50 ㎎/L, respectively. In the nitrite exposure experiment with zoea and megalopa stage larvae of tiger crab, survival rate was decreased in a concentration and exposure period-dependent way. The growth rate of zoea and megalopa stage larvae of tiger crab exposed to nitrite decreased at greater than 150 ㎎/L nitrite concentration.