• Title/Summary/Keyword: production stability

Search Result 1,374, Processing Time 0.026 seconds

A Case Study on Teacher Recruitment Experience of Private Kindergarten Director (사립유치원장의 교사 채용 경험에 관한 사례연구)

  • Pyun, Young-Shin
    • Journal of Digital Convergence
    • /
    • v.16 no.10
    • /
    • pp.199-204
    • /
    • 2018
  • The purpose of this study is to investigate the factors and reasons for hiring kindergarten teachers and to provide information for successful employment to the college. 12 private kindergarten chiefs over 10 years of experience were conducted in - depth interviews. In-depth interview data were analyzed using open coding analysis. 11 sub - factors of each core concept were derived, and they were nominated as 4 outline (character, sociality, personality & professionalism factors). All of the researchers perceived the sincerity, interpersonal stability, honesty, and ability to perform the curriculum as the most important factors to consider, and the teacher with good personality was perceived as the precondition of successful teacher's job performance. In the college, through the production of portfolios by subject, we raised the necessity of institutionalization of educational volunteer activities such as vacation - based education in addition to on - the - spot education at school and development of liberal arts curriculum to develop capacity for community life. And to develop and operate a field-oriented comparative education program to strengthen the competence of the majors.

Physicochemical Properties of Carrot Juice Fermented by Leuconostoc mesenteroides SM (김치젖산균에 의한 당근 발효음료의 물리화학적 성질)

  • Jo, Sun-Ja;Oh, Soo-Myung;Jang, Eun-Kyung;Hwang, Ki;Lee, Sam-Pin
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.37 no.2
    • /
    • pp.210-216
    • /
    • 2008
  • Leuconostoc mesenteroides SM isolated from a raw carrot was used for the fermentation of carrot juice (CJ). Lactic acid fermentation of CJ was performed at $25^{\circ}C$ for 24 hr with $0{\sim}20%$ sucrose concentration, resulting in the production of mucilage. The fermented CJ showed the complete conversion of sugar into dextran after fermentation for 24 hr in the presence of sucrose below 15% concentration. With 15% sucrose, the fermented CJ had pH 3.8, 0.9% acidity, consistency index of $3.5\;Pa{\cdot}s^n$. After cold storage for 3 weeks, fermented CJ showed slight increase in acidity and relatively constant value in pH; however, the consistency index, red color value and viable cell counts were slightly decreased for 3 weeks. The ${\beta}-carotene$ content in CJ was drastically decreased by lactic acid fermentation for 24 hr, indicating $72\;{\mu}g/mL$ as compared to $142\;{\mu}g/mL$. The fermented CJ had improved body texture, red color and stability without sedimentation.

Neoliberal Urbanization and Urban Enclosure (I): A Theoretical Intervention (신자유주의 도시화와 도시 인클로저(I): 이론적 검토)

  • Kim, Yongchang
    • Journal of the Korean Geographical Society
    • /
    • v.50 no.4
    • /
    • pp.431-449
    • /
    • 2015
  • Philosophical roots and discussion frames of neoliberalism are very heterogeneous and approaches to neoliberalism including anarchism, post-neoliberalism also take diverse stances. Even if neoliberalism is losing legitimacy and stability through the global financial crisis, 2008, spatial perspective is becoming more and more important as neoliberalism constantly evolve with creating immense variations. Especially, urban space has become strategically crucial arenas as spatio-temporal strategies and generative nodes for reproduction of neoliberalism. Urban enclosure plays a key role in the specific process of neoliberal urbanization as a kind of capitalist formal and real subsumption. Contemporary capitalism continuously has been sustaining the accumulation by dispossession based on urban enclosure through reshaping the primitive accumulation mechanism. These enclosures are embodied by the change of public use concept from public ownership to economic benefits and public-private taking for private capital. Urban enclosure promotes reification deepening the separation and alienation of workers from the means of production and survival, and interdiction from free place appropriation, transformation of urban economy to patrimonial forms. Also it is pervasive in a daily life space and everyday experience in the city, and private tangled social rules dominate public space and the publicity of space.

  • PDF

Immobilization of Bacillus sp. Strains, Catalase Producing Bacteria and Their Hydrogen Peroxide Removal Characteristics (카탈라제를 생산하는 고초균 (Bacillus sp.)의 고정화 및 과산화수소 분해 특성)

  • Han, Kyung-Ah;Jang, Yun-Hee;Rhee, Jong-Il
    • KSBB Journal
    • /
    • v.25 no.6
    • /
    • pp.520-526
    • /
    • 2010
  • In this work we have investigated the production of catalase from Bacillus sp. strains, which were screened and identified from soil. These strains were cultivated in shaking flasks with tryptic soy broth (TSB) at $30^{\circ}C$ and 200 rpm. Effects of the temperature and pH on the stability of the native catalase and whole cell viability were studied in the temperature range of $25-60^{\circ}C$ and the pH range of 7-13. Korean natural zeolite was added to culture medium and mixed with microorganisms for 24 hours. The native catalase maintained its activity over $50^{\circ}C$. The enzyme acitiviy of the catalase from Bacillus flexus BKBChE-3 was highest among the Bacillus sp. strains studied. Bacillus flexus BKBChE-3 and immobilized Bacillus cells have survived under extreme conditions of over $50^{\circ}C$ and pH 12. 60 mL of 10.5 mM $H_2O_2$ solution were entirely removed within 1 hour with catalase produced from Bacillus sp. on the flask. When Bacillus cells were immobilized on Korean natural zeolite, colony forming unit of Bacillus flexus BKBChE-3 was increased and high efficiency of hydrogen peroxide removal was observed.

Optimization of Esterification of Jatropha Oil by Amberlyst-15 and Biodiesel Production (Amberlyst-15를 이용한 자트로파 오일의 에스테르화 반응 최적화 및 바이오디젤 생산)

  • Choi, Jong-Doo;Kim, Deog-Keun;Park, Ji-Yeon;Rhee, Young-Woo;Lee, Jin-Suk
    • Korean Chemical Engineering Research
    • /
    • v.46 no.1
    • /
    • pp.194-199
    • /
    • 2008
  • In this study, the effective method to esterify the free fatty acids in jatropha oil was examined. Compared to other plant oils, the acid value of jatropha oil was remarkably high, 11.5 mgKOH/g. So direct transesterification by a base catalyst was not suitable for the oil. After the free fatty acids were esterified with methanol, jatropha oil was transesterified. The activities of four solid acid catalysts were tested and Amberlyst-15 showed the best activity for the esterification. After constructing the experiment matrix based on RSM and analyzing the statistical data, the optimal esterification conditions were determined to be 6.79% of methanol and 17.14% of Amberlyst-15. After the pretreatment, jatropha biodiesel was produced by the transesterification using KOH in a pressurized batch reactor. Jatropha biodiesel produced could meet the major specifications of Korean biodiesel standards; 97.35% of FAME, 8.17 h of oxidation stability, 0.125% of total glycerol and $0^{\circ}C$ of CFPP.

Electrochemical Treatment of Dyeing Wastewater using Insoluble Catalyst Electrode (불용성 촉매전극을 이용한 염색폐수의 전기화학적 처리)

  • Um, Myeong-Heon;Ha, Bum-Yong;Kang, Hak-Chul
    • Clean Technology
    • /
    • v.9 no.3
    • /
    • pp.133-144
    • /
    • 2003
  • In this study, Insoluble catalyst electrode for oxide systems were manufactured, by using of them, carried out experiments on electrolytic treatment of dyeing wastewater containing persistent organic compounds, and then made a comparative study of the efficiency of treatment for environmental pollutants and whether each of them is valuable of not as an electrode for soluble electrode(Fe, Al) and insoluble electrode(SUS, R.C.E; Replaced Catalyst Electrode) which were used in the electrolytic system. Besides, it was investigated the conditions for electrolytic treatment to find the maximum efficiency of electrolytic treatment. As the result of this study, by using of insoluble catalyst electrode for oxide can solved the stability of electrode that is one of the greatest problems in order to put to practical use of electrolysis process in the treatment of the sewage and wastewater and the result runs as follows; 1. The durability of insoluble catalyst electrode(R.C.E) can be verified the most favorable when the molar ratio of $RuO_2-SnO_2-IrO_2-TiO_2$(4 compounds system) is 70/20/5/5. 2. The efficiency of treatment was obtained a more than 90% goodness for CODMn and also a good results for T-N removal in the experimental conditions of the distance of electrode 5 mm, time of electrolysis 60 minutes, permissible voltage 10V, processing capacity $0.5{\ell}$.

  • PDF

Production and High Temperature Mechanical Properties of Ti-TiC Composite by Reaction Milling (반응밀링법에 의한 Ti-TiC 복합재료의 제조 및 고온 기계적 특성)

  • Jin, Sang-Bok;Choe, Cheol-Jin;Lee, Sang-Yun;Lee, Jun-Hui;Kim, Sun-Guk
    • Korean Journal of Materials Research
    • /
    • v.8 no.10
    • /
    • pp.918-924
    • /
    • 1998
  • This study has been carried out to investigate the effect of reaction milling time on the synthesis of Ti- TiC p powder synthesised from the elemental titanium and activated carbon by reaction milling(RM), and the effect of vacu­u urn hot pressing temperature and TiC volume fraction on microstructural and mechanical properties of Ti- TiC com­p posite $\infty$ns이idated by vacuum hot pressing(VHP).T The elemental powders of titanium and activated carbon can be converted into Ti- TiC composite powders by reac­t tion milling for about 300hours, and were the average grain size of the as- milled powders has been measured to be a about $5\mu\textrm{m}$. The relative density of Ti- TiC VHPed above $1000^{\circ}C$ during Ihr is about 98% and the mechanical properties o of In- situ Ti- TiC composites are improved by TiC particle dispersed uniformly on titanium matrix. In order to investi­g gate thermal stability of Ti- TiC composite, after annealing at $600^{\circ}C$ for 80hrs micro- Vickers hardness have been per­f formed, and the values have been shown little changed as compared with those before annealing. The compact has b been tested on high temperature compressive test at $700^{\circ}C$ and has showed a high temperature compressive strength of 330MPa in a Ti- 20vol% TiC.

  • PDF

An Experimental Study on the Properties of Engineering and Shrinkage Cracking Reduction of Fiber Reinforced Concrete Using Recycled Fine Aggregate (섬유보강 순환잔골재 콘크리트의 공학적 특성 및 수축균열저감특성에 관한 실험적 연구)

  • Kim, Gyu-Yong;Nam, Jeong-Soo;Kim, Moo-Han;Lee, Do-Heun;Song, Ha-Young
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.4 no.3
    • /
    • pp.82-89
    • /
    • 2009
  • Recently, the study is progressing actively about manufacture skill of concrete for promoted recycled aggregate and concrete made into recycled aggregate in the construction production field. But, application and study about recycled fine aggregate insufficient compared to recycled coarse aggregate. So, in this study, it presents basic data for development of environmental load reduction fiber reinforcement recycled fine aggregate concrete by comparison and investigation about engineering properties and shrinkage cracking of fiber reinforcement recycled find aggregate concrete for increasing shrinkage cracking reduction and long term stability of environmental load reduction concrete used recycled fine aggregate. In the result of the study, compared to natural fine aggregate, a crack-extent increased by applying recycled fine aggregate, moreover, as a water cement ratio increased, the crack size increased, as well. In addition, it's shown that the specimen mixed with PVA and Nylon, among all kinds of fibers, showed the smallest crack size, so it's verified that the mix of fiber had an effect on decreasing crack-extent.

  • PDF

A study on job-satisfaction and Turn-over(Transferability) of Dental Technicians in Korea (한국 치과기공사의 직무만족과 직장이동에 관한 연구)

  • Lim, Byung-Chul
    • Journal of Technologic Dentistry
    • /
    • v.11 no.1
    • /
    • pp.71-81
    • /
    • 1989
  • This study was aimed for bettering productivity and technical level of the dental 1 aboratory, and helping the dental technician's benefits and rights, and then endowing them some belonged atmospher and stability on their post by Improving job- satisfaction and maintaining the transferability of one's post at a proper limitation. Therefore, 320 dental technicians extracted randomly from all the technicians working at 494 dental laboratories were subjected for this study. The approach to the study was a way through some postal questionaires executed from March 29, 1988 until May 4, the same year, in which total 254 technicians answered, showing 79% resp"nserate. responserate. The data-analysis was done by a model of the dental technician's transferability from their post, as considering Mobley's(1978)-model of post-transferability, and results through the study are as follows : 1. Satisfaction at a given post showed that the married is better than the unmarried(<0.05), and the experienced is better than the inexperienced(P<0.01). 2. Age, sex, educational experience, and one's service-duration did not affect significantly to the respondent's satisfaction on their post, statistically. 3. Satisfaction at a given post differed in adccordance with given conditions of one's post, i. e.,it stowed high when the monthly payment was good(P<0.05), and when too much duty on their job was given, it was the worst as shown in an example of the next order, too much

  • PDF

Cost-Benefit Analysis Method for Ageing Equipment of Chemical Plants Using Risk Assessment (위험성평가를 이용한 노후설비에 대한 비용 편익분석 방법)

  • Jung, Soomin;Jung, Changmo;Kang, Seok-Min;Chae, Seungbeen;Kang, Seung-Gyun;Ko, Jae Wook
    • Journal of the Korean Institute of Gas
    • /
    • v.24 no.4
    • /
    • pp.84-92
    • /
    • 2020
  • Most facilities in chemical plants operate in environments that are outside the range of temperature and pressure that can be encountered on a daily basis, and are vulnerable to aging due to these stresses and environmental conditions. The facilities exposed to these conditions are not only likely to fail due to cumulative damage, but also lead to accidents if maintenance and replacement are not performed.Recommendation guidelines called risk-based inspection are widely used around the world-wide. However, limits exist for facilities that have already elapsed for a certain. As a result of the survey on the aging of Ulsan industrial complex in Korea, which carries out proper inspection, many of the facilities have been used for 20 years. Also, most of the facilities where the accident occurred have been in operation for more than 20 years. Therefore, this study suggested criteria for classifying devices that have exceeded a certain period of use as obsolete facilities. In addition, quantitative risk assessment was conducted. The safety investment method using the cost-benefit analysis method was proposed in order to calculate the loss cost and reduce the risk by expressing the risks of the corresponding aged facility as an Economic index. By utilizing the method of cost-benefit analysis of old facilities using the quantitative risk assessment presented in this study, it can be expected to improve the performance and life of old facilities, improve production efficiency and reliability of the system of facilities, change the recognition of safety management costs, increase employee stability, and reduce loss costs.