다중처리기 시스템을 위한 적응적 작업할당 방법의 개선

옥기상(Ok Ki Sang),박준석(Park Joon Seok),이원주(Lee won Joo),전창호(Jeon Chang Ho) 한국정보처리학회 1999 정보처리학회논문지 Vol.6 No.6

In adaptive job allocation method for multiprocessor systems a job is folded, or split in two halves, to fit for an available subcube in order to reduce the waiting time of jobs. In this method, however, since a job is folded whenever a subcube with the proper size is not found, the prolonged execution time caused by job split may override the savings in waiting time, in which case the total execution cost of jobs may be increased. In this paper, an improved adaptive job allocation algorithm, called Estimate-fold allocation, is presented and evaluated. The proposed algorithm estimates the costs and takes the better of two alternatives; folding right away and waiting until a bigger subcube becomes available. The average total job execution cost of our algorithm is calculated and compared to those of the conventional adaptive, buddy, and gray-mode algorithms through simulations. The results shows that our proposed algorithm performs better than others.

Effect of Trinexapac-ethyl on Zoysiagrass Quality under a Shade Condition

Chang-Ho Ok(옥창호) 한국잡초학회·한국잔디학회 2006 Weed & Turfgrass Science Vol.20 No.1

'Meyer' zoysiagrass(Zoysia japonica Steud.)는 일반적으로 미국 중부지역에서 골프장 페어웨이 또는 티에 일반적으로 많이 쓰이는 잔디로 적은 시비와 관수와 함께 좋은 플래이를 제공한다. 하지만 그늘 지역에서의 생육이 저하되어 품질을 떨어뜨린다. 감소되어진 광량은 잔디 잎의 웃자람을 일으키며 밀도가 저하되고 약한 잔디 생육과 함께 답압이나 디보트에 따른 재생을 저하시킨다. 이 실험의 목적은 TE의 처리가 그늘 지역에서의 잔디의 웃자람을 억제하고 품질을 향상 시키는가를 알아보기 위함에 있다. 이 실험에서 두 가지 처리는 차광 조건(0%, 79%, 92% 차광막) 과 TE [0, 48(0.5x), 96gㆍha?¹ a.i(1x)]로 적용하였다. 무 차광 처리 시, 0.5x-비율로 TE처리에서 4 주후 무 처리구에 비해 18%의 잔디 예초물의 감소를 보였고 1x-비율의 TE 처리는 30~38%의 예초물 감소를 보였다. 매달 1x-비율의 TE 처리 시 무 차광 처리와 79% 차광에서 zosiagrass의 밀도를 증가 시켰다. 무 처리에 비해 두 TE 비율의 처리가 잔디의 웃자람을 감소시켰으며 1x-비율로 TE 처리 시 79% 차광에서 잔디 품질이 저하되는 것이 지연되었다. 이 실험에서 그늘진 지역에서의 TE 처리가 zoysiagrass 의 웃자람을 줄이고 잔디 품질을 향상 시킨다는 것을 알 수 있었다. 'Meyer' zoysiagrass(Zoysia japonica Steud.) is a popular turfgrass species used for transition zone golf course fairways and tees in mid U.S.A golf coursesbecause it is generally winter hardy while providing an excellent playing surface with minimal chemical and irrigation inputs. However, its functionality declines easily in many of the shaded areas of these courses. Reduced irradiance causes excessive shoot elongation, reduced tillering, and weak plants that are poorly suited to tolerate or recover from traffic and devoting. Trinexapac-ethyl (TE) effectively reduces gibberellic acid (GA) biosynthesis and subsequent shoot cell elongation. This study was initiated to evaluate TE effect on shoot elongation and stand persistence under two levels of shade in 'Meyer' zoysiagrass. A mature stand of 'Meyer' was treated with all combinations of three levels of shade(0%, 79%, and 92%) and three levels of monthly TE [0, 48gㆍha?¹ a.i(0.5x) and 96gㆍha?¹ a.i(1x)]. In full sun, the TE at 48gㆍha?¹ a.i reduced clipping yield by 18% over a four-week period and, whereas the TE at 96gㆍha?¹ a.i by 30% to 38%. Monthly application of TE at the 96gㆍha?¹ a.i increased 'Meyer' tiller density in full sun and under 79% shade. Both rates of TE consistently reduced shoot growth under shade relative to the shaded control. Only the monthly applications of the TE at 96gㆍha?¹ a.i consistently delayed loss of quality under 79% shade. Our results indicate TE can be an effective management practice to increase 'Meyer' zoysiagrass persistence in shaded environments.

Effect of Trinexapac-ethyl on Zoysiagrass Quality under a Shade Condition

옥창호,Ok, Chang-Ho Turfgrass Society of Korea 2006 한국잔디학회지 Vol.20 No.1

'Meyer' zoysiagrass(Zoysia iaponica Steud.)는 일반적으로 미국 중부지역에서 골프장 페어 웨이 또는 티에 일반적으로 많이 쓰이는 잔디로 적은 시비와 관수와 함께 좋은 플래이를 제공한다. 하지만 그늘 지역에서의 생육이 저하되어 품질을 떨어뜨린다. 감소되어진 광량은 잔디 잎의 웃자람을 일으키며 밀도가 저하되고 약한 잔디 생육과 함께 답압이나 디보트에 따른 재생을 저하시킨다. 이 실험의 목적은 TE의 처리가 그늘 지역에서의 잔디의 웃자람을 억제하고 품질을 향상 시키는가를 알아보기 위함에 있다. 이 실험에서 두 가지 처리는 차광 조건(0%, 79%, 92% 차광막) 과 TE [0, 48(0.5x), $96g{\cdot}ha^{-1}\;a.i(1x)$]로 적용하였다. 무 차광 처리 시, 0.5x-비율로 TE처리에서 4 주후 무 처리구에 비해 18%의 잔디 예초물의 감소를 보였고 1x-비율의 TE 처리는 $30{\sim}38%$의 예초물 감소를 보였다. 매달 1x-비율의 TE 처리 시 무 차광 처리와 79% 차광에서 zosiagrass의 밀도를 증가 시켰다. 무 처리에 비해 두 TE 비율의 처리가 잔디의 웃자람을 감소시켰으며 1x-비율로 TE 처리 시 79% 차광에서 잔디 품질이 저하되는 것이 지연되었다. 이 실험에서 그늘진 지역에서의 TE 처리가 zoysiagrass 의 웃자람을 줄이고 잔디 품질을 향상 시킨다는 것을 알 수 있었다. 'Meyer' zoysiagrass(Zoysia japonica Steud.) is a popular turfgrass species used for transition zone golf course fairways and tees in mfd U.S.A golf courses because it is generally winter hardy while providing an excellent playing surface with minimal chemical and irrigation inputs. However, its functionality declines easily in many of the shaded areas of these courses. Reduced irradiance causes excessive shoot elongation, reduced tillering, and weak plants that are poorly suited to tolerate or recover from traffic and devoting. Trinexapac-ethyl (TE) effectively reduces gibberellic acid (GA) biosynthesis and subsequent shoot cell elongation. This study was initiated to evaluate TE effect on shoot elongation and stand persistence under two levels of shade in 'Meyer' zoysiagrass. A mature stand of 'Meyer' was treated with all combinations of three levels of shade(0%, 79%, and 92%) and three levels of monthly TE [0, 48 $g{\cdot}ha^{-1}$ a.i(0.5x) and 96 $g{\cdot}ha^{-1}$ a.i(1x)]. In full sun, the TE at 48 $g{\cdot}ha^{-1}$ a.i reduced clipping yield by 18% over a four-week period and, whereas the TE at 96 $g{\cdot}ha^{-1}$ a.i by 30% to 38%. Monthly application of TE at the 96 $g{\cdot}ha^{-1}$ a.i increased 'Meyer' tiller density in full sun and under 79% shade. Both rates of TE consistently reduced shoot growth under shade relative to the shaded control. Only the monthly applications of the TE at 96 $g{\cdot}ha^{-1}$ a.i consistently delayed loss of quality under 79% shade. Our results indicate TE can be an effective management practice to increase 'Meyer' zoysiagrass persistence in shaded environments.

Effect of Rootzone Mixes Amended with Crumb Rubber on the Physical Properties

청쉬콩,옥창호,Chong, She-Kong,Ok, Chang-Ho Turfgrass Society of Korea 2006 한국잔디학회지 Vol.20 No.1

본 연구는 폐 타이어를 미사질 토양에 혼합하여 경기장 식재층으로서의 질을 향상 시키고자 실시하였다. 특히 본 실험을 통해 토양에 혼합되는 폐 타이어의 입경 크기와 혼합량에 따라 식재층의 토양 물리적 특성을 측정하고자 하였다. 실험에서 두 종류의 토양 [Arenzville silt loam(coarse-silty, mixed, nonacid, mesic Typic Udifluvents), Hosmer silty clay loam(fine-silty, mixed, mesic Typic Fragiudalfs)]과 입경 크기(3.5, 6.5, 9.5mm)에 따라 세 가지의 폐 타이어를 사용하였다. 각각 크기별 토양에 혼합된 폐 타이어의 혼합 비율은 0에서 0.4 $g{\cdot}g^{-1}$ 사이였다. 각각의 처리구에 대한 실험 진행 및 물리성 조사는 미국 골프협회 Green Section Record 의 기준 방법에 준해서 실시하였다. 본 실험의 결과 토양에 혼합된 폐 타이어의 비율이 증가 할수록 토양의 총 공극량은 감소하였다. 하지만 입경 크기와 상관없이 폐 타이어의 혼합량이 0.15 $g{\cdot}g^{-1}$ 이하인 경우에는 대공극과 포화투수계수에 차이가 없었다. 반면 폐타이어가 0.15 $g{\cdot}g^{-1}$ 이상으로 혼합된 토양은 대 공극, 포화 투수계수, 그리고 공기 투과율이 대조구에 비해 통계적으로 유의하게 개선되었다. This research was initiated to enhance the tilth of fine-textured soil for turf growth by incorporation of crumb rubber shredded from used tires. A specific objective was to determine the physical properties of soil mixes amended with different grade and amount of crumb rubber in soils. Two soils and three different grades(3.5, 6.5 and 9.5 mm) of crumb rubber were used. The soils selected were an Arenzville silt loam(coarse-silty, mixed, nonacid, mesic Typic Udifluvents) and a Hosmer silty clay loam(fine-silty, mixed, mesic Typic Fragiudalfs). The amount of crumb rubber mixed in soil ranged from 0 to 0.4 $g{\cdot}g^{-1}$(using 0.05 $g{\cdot}g^{-1}$) increments and 0 as a control. For each treatment, soil cores were constructed following the recommendation by the United States Golf Association Green Section Record. Results indicated that porosity of the mixes decreased as the amount of crumb rubber increased. Regardless of the grade of crumb rubber, mixes with less than 0.15 $g{\cdot}g^{-1}$ of crumb rubber in fine-textured soil could not enhance their macro-porosity and hydraulic conductivity. However, as the amendment increased over 0.15 $g{\cdot}g^{-1}$, the tilth of the mixes had improved significantly macro-porosity, hydraulic conductivity and air permeability, as compared with a control.

Evaluation of Fungicides for Dollar Spot Control on Creeping Bentgrass and Annual Bluegrass Putting Green

제임스 팝코,옥창호,정근화,Popko, James,Ok, Chang-Ho,Jung, Geun-Hwa Turfgrass Society of Korea 2010 한국잔디학회지 Vol.24 No.2

Sclerotinia homoeocarpa F.T. Bennett에 의한 동전마름병은 북미에서 가장 흔하며 경제적으로 중요한 잔디병이다. 동전마름병을 관리하기 위해서는 봄부터 가을까지 잦은 약제처리를 요구한다. 본 연구에서는 동전마름병에 대한 농약의 단용 혹은 다른 약제와의 혼용 처리를 통해 약제의 효과를 평가하고, Rhizoctonia solani에 의한 브라운 패치(brown patch)와 Pythium aphanidermatum에 의한 피시움마름병에 대한 이차 방제효과(secondary effect)도 조사하였다. 평가기간동안 동전마름병은 유리한 기상조건으로 인하여 평가하기에 적당한 병 발생을 보였다. 처리한 살균제 중 Rhapsody 단용처리를 제외한 모든 살균제의 단용 혹은 혼용처리에서 동전마름병에 대한 유의성 있는 방제효과가 인정되었다. 또한 동일한 처리구에서 브라운 패치에 대한 병 방제효과도 인정되었다. 모든 살균제에서 약해는 관찰되지 않았다. Dollar spot, caused by Sclerotinia homoeocarpa F.T. Bennett, is the most economically important turfgrass disease on golf courses in North America due to its persistent nature. Fungicides, plant growth regulators, and other products were evaluated for preventative control of dollar spot and the secondary effects on brown patch and Pythium in a mixed stand of creeping bentgrass and annual bluegrass golf course putting green. Most fungicides provided excellent control of dollar spot throughout the trial but Rhapsody alone did not provide adequate control. Civitas applied alone and tank-mixed with Banner MAXX(R) and Daconil Ultrex(R) provided acceptable control throughout the study. No phytotoxicity was observed on any of the treatments applied but a darker green color and reduction in turfgrass growth was observed in a treatment with plant growth regulator, Trimmit. Treatments that contained Civitas and the Civitas Harmonizer also exhibited green pigmentation.

Effect of Rootzone Mixed Amended with Crumb Rubber on the Physical Properties

She-Kong Chong(청쉬콩),Chang-Ho Ok(옥창호) 한국잡초학회·한국잔디학회 2006 Weed & Turfgrass Science Vol.20 No.1

본 연구는 폐 타이어를 미사질 토양에 혼합하여 경기장 식재층으로서의 질을 향상 시키고자 실시하였다. 특히 본 실험을 통해 토양에 혼합되는 폐 타이어의 입경 크기와 혼합량에 따라 식재층의 토양 물리적 특성을 측정하고자 하였다. 실험에서 두 종류의 토양 [Arenzville silt loam(coarse-silty, mixed, nonacid, mesic Typic Udifluvents), Hosmer silty clay loam(fine-silty, mixed, mesic Typic Fragiudalfs)]과 입경 크기(3.5, 6.5, 9.5㎜)에 따라 세 가지의 폐 타이어를 사용하였다. 각각 크기별 토양에 혼합된 폐 타이어의 혼합 비율은 0에서 0.4 gㆍg?¹ 사이였다. 각각의 처리구에 대한 실험 진행 및 물리성 조사는 미국 골프협회 Green Section Record의 기준 방법에 준해서 실시하였다. 본 실험의 결과 토양에 혼합된 폐 타이어의 비율이 증가 할수록 토양의 총 공극량은 감소하였다. 하지만 입경 크기와 상관없이 폐 타이어의 혼합량이 0.15 gㆍg?¹ 이하인 경우에는 대공극과 포화투수계수에 차이가 없었다. 반면 폐타이어가 0.15 gㆍg?¹ 이상으로 혼합된 토양은 대 공극, 포화 투수계수, 그리고 공기 투과율이 대조구에 비해 통계적으로 유의하게 개선되었다. This research was initiated to enhance the tilth of fine-textured soil for turf growth by incorporation of crumb rubber shredded from used tires. A specific objective was to determine the physical properties of soil mixed amended with different grade and amount of crumb rubber in soils. Two soils and three different grades(3.5, 6.5 and 9.5 ㎜) of crumb rubber were used. The soils selected were an Arenzville silt loam(coarse-silty, mixed, nonacid, mesic Typic Udifluvents) and a Hosmer silty clay loam(fine-silty, mixed, mesic Typic Fragiudalfs). The amount of crumb rubber mixed in soil ranged from 0 to 0.4 gㆍg?¹(using 0.05 gㆍg?¹) increments and 0 as a control. For each treatment, soil cores were constructed following the recommendation by the United States Golf Association Green Section Record. Results indicated that porosity of the mixed decreased as the amount of crumb rubber increased. Regardless of the grade of crumb rubber, mixes with less than 0.15 gㆍg?¹ of crumb rubber in fine-textured soil could not enhance their macro-porosity and hydraulic conductivity. However, as the amendment increased over 0.15 gㆍg?¹, the tilth of the mixes had improved significantly macro-porosity, hydraulic conductivity and air permeability, as compared with a control.

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.

환자 만족도 조사를 통한 QI활동의 효과 평가 : 일개 병원을 중심으로

박연옥,김미숙,고은정,김연정,홍창호 한국의료QA학회 1998 한국의료질향상학회지 Vol.5 No.2

Background : Evaluation of patient's satisfaction is one of the most important aspects of quality improvement. If the patient highly satisfies with the medical service provided in the hospital, he/she will be likely to visit the same hospital again. Patient's satisfaction of a particular hospital is directly correlated with hospital profits as well as reputation in the community. For this reason, various kinds of survey measuring satisfaction level have been performed and many kind of QI activities for enhancing the profits as well as reputation in the community. For this reason, various kinds of survey measuring satisfaction level have been performed and many kind of QI activities for enhancing the patient's satisfaction. This study is to find the effect of hospital QI activities on the patient's satisfaction level. Methods : After questionnares were developed, survey of measuring satisfaction level was performed in August. 1998. On the basis of survey results. Ql activities were carried out to attain the target point of 4.0 and subsequent survey was done in November. 1998. Results : With three main principles of "problem solving approach with kindness". "helping patient to participate in medical procedure with sufficient information", and "putting employees into practice of attitude with human respect", the average level of satisfaction was enhanced from 3.45 to 3.55 level. Also kindness level of employees was increased from 3.71 to 3.82. Level of dissatisfaction about insufficient explanation and unkind attitude was dropped from 69% to 48% and from 82% to 46% respectively. Conclusion : With the result of this study overall satisfaction level was enhanced. In order to keep these advantages a operation of Quality Improvement Task Force Team in each subject will be required.

아귀목(Order Lophiiformes)어류의 2 미기록종

윤창호,허성희,조춘옥 한국어류학회 2000 韓國魚類學會誌 Vol.12 No.4

아귀목 어류에 속하는 Lophiodes insidiator(Regan, 1921)과 Halieutaea fumosa Alcock 1894의 한국산 미기록 어류를 부산주변의 해역에서 각각 1개체씩 채집하였다. Lophiodes insidiator의 국명은 "용아귀", Halieutaea fumosa는 "민부치"라 신칭하였으며, 이들 종들의 계수계측형질을 기재하고 검색표와 사진을 제시하였다. Two species of anglerfishes, Lophiodes insidiator (Regan, 1921) and Halieutaea fumosa Alcock 1894 that were unrecorded in Korea, were collected from the adjacent waters of Busan, Korea. These species were described and figured as first record from Korea. New korean names, Yong-Ah-Gui and Min-Bu-Chi were proposed for Lophiodes insidiator and Halieutaea fumosa.

한국산 빙어속(Genus Hypomesus)어류의 분류학적 재검토

김익수,윤창호,이완옥 한국어류학회 1999 韓國魚類學會誌 Vol.11 No.2

To use of the precise scientific name of the genus Hypomesus from Korea, taxonomic revison of the genus Hypomesus was studied based on the specimens collected at 11 sites of the reservoirs and estuaries from Korea. The most population of the Hypomesus nipponensis was taken the pneumatic duct that connected between the anterior part of swim bladder and stomach. The number of pyroric caeca of the specimens was zero to five. The number of chromatophore at isthmus was fifty to one hundred. And authors were confirmed with the membrane structure across the nasal cavity. Then, we think that the scientific name of the pond-smelt at Korea is Hypomesus nipponensis by these characters. The Yangyang population that have the sixty-two to sixty-three of vertebrae, was confirmed with H. japonicus.