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The Effect of Process Maturity on the Performance of Industrial R&D Projects (프로세스 성숙도가 기업 R&D 프로젝트의 성과에 미치는 영향에 관한 연구)

  • Hong, Soon-Wook
    • IE interfaces
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    • v.16 no.3
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    • pp.362-374
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    • 2003
  • The major objective of this paper is to empirically examine the effect of process maturity on the performance of industrial R&D projects. Process maturity, a fundamental concept of the Capability Maturity Model developed by Software Engineering Institute, represents the essential of Total Quality Management (TQM). Based on literature, our research model constructs process maturity in terms of structured process, goal setting and controlling, metrics, and process learning; and links it to the R&D performance that consists of technical, commercial and managerial successes. The model also includes firm size as a moderator of different effects that process maturity may have across firms. Measures for process maturity are based on the best practices identified in literature. Data are obtained from 77 successful R&D projects carried out by Korean manufacturing firms. Multiple regression and t-test are used to test proposed hypotheses. Findings are as follows. (1) In the R&D process, process maturity partially contributes to the performance of R&D projects. More specifically, goal setting and controlling-related practices drive both technical and commercial successes, while process learning-related practices drive commercial success. In contrast, traditionally emphasized elements such as structured process or metrics are found not to be significant. (2) The degree of process maturity is significantly higher in large firms. (3) Process maturity impacts on commercial success in the case of large firms, whereas it does on technical success in the case of small firms. The results imply that the TQM principles are partially associated with R&D performance, and the nature of benefit from high maturity could vary according to firm size.

Study of Efficacy and Safety of Tianwangbuxin-dan for Poststroke Depression: A Randomized, Double Blinded, Non-inferiority Trial (뇌졸중 후 우울증에 대한 천왕보심단의 유효성 및 안전성 연구 : 무작위 배정, 이중맹검, 비열등성 연구)

  • Lee, Il-Suk;Kim, Mun-Soo;Lee, Sang-Kwan
    • The Journal of Internal Korean Medicine
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    • v.35 no.2
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    • pp.145-156
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    • 2014
  • Objectives : The aim of this study was to compare Tianwangbuxin-dan to Fluoxetine for antidepressive efficacy and safety in poststroke depression (PSD). Methods : A randomized, double blinded, non-inferiority trial was conducted. 113 PSD patients were recruited from a stroke center. Except for the 25 excluded patients, 88 PSD patients were randomly given either Tianwangbuxin-dan 1100 mg or Fluoxetine 20 mg per a day for 16 weeks. PSD was evaluated using Beck's depression inventory (BDI) and Hamilton depression rating scale (HDRS) and followed every fourth week. Repeated measure analysis of variance (ANOVA) was used to compare and contrast the depression scores of the two groups and to compare them among the evaluation times, at the beginning, $4^{th}$, $8^{th}$, $12^{th}$ and $16^{th}$ weeks. In addition, independent t-tests were used to find the difference between two groups at every evaluation time. Results : Finally, 88 PSD patients were included in the study, 63 PSD patients completed the procedure and 25 PSD patients were dropped out by the incompliance or withdrawal of consent. Tianwangbuxin-dan (or Fluoxetine) improved the depression of stroke patients and the efficacy of Tianwangbuxin-dan was not inferior to that of Fluoxetine. In addition, there was no significant side effect in two groups. Conclusions : This study showed that antidepressive efficacy and safety of Tianwangbuxin-dan in PSD patients.

Effect of Cytokines and bFGF on the Osteoclast Differentiation Induced by $1\;{\alpha},25-(OH)_2D_3$ in Primary Murine Bone Marrow Cultures

  • Chae, Han-Jung;Kang, Jang-Sook;Bang, Byung-Gwan;Cho, Seoung-Bum;Han, Jo-Il;Choi, Joo-Young;Kim, Hyung-Min;Chae, Soo-Wan;Kim, Hyung-Ryong
    • The Korean Journal of Physiology and Pharmacology
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    • v.3 no.6
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    • pp.539-546
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    • 1999
  • Bone is a complex tissue in which resorption and formation continue throughout life. The bone tissue contains various types of cells, of which the bone forming osteoblasts and bone resorbing osteoclasts are mainly responsible for bone remodeling. Periodontal disease represents example of abnormal bone remodeling. Osteoclasts are multinucleated cells present only in bone. It is believed that osteoclast progenitors are hematopoietic origin, and they are recruited from hematopoietic tissues such as bone marrow and circulating blood to bone. Cells present in the osteoclast microenvironment include marrow stromal cells, osteoblasts, macrophages, T-lymphocytes, and marrow cells. These cells produce cytokines that can affect osteoclast formation. In vitro model systems using bone marrow cultures have demonstrated that $IL-l{\beta},\;IL-3,\;TNF-{\alpha},$ bFGF can stimulate the formation of osteoclasts. In contrast, IL-4 inhibits osteoclast formation. Knowledge of cytokines and bFGF that affect osteoclast formation and their capacity to modulate the bone-resorbing process should provide critical insights into normal calcium homeostasis and disorders of bone turnover such as periodontal disease, osteoporosis and Paget's disease.

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Bioproduction of trans-10,cis-12-Conjugated Linoleic Acid by a Highly Soluble and Conveniently Extracted Linoleic Acid Isomerase and an Extracellularly Expressed Lipase from Recombinant Escherichia coli Strains

  • Huang, Mengnan;Lu, Xinyao;Zong, Hong;Zhuge, Bin;Shen, Wei
    • Journal of Microbiology and Biotechnology
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    • v.28 no.5
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    • pp.739-747
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    • 2018
  • The low solubility and high-cost recovery of Propionibacterium acnes polyunsaturated fatty acid isomerase (PAI) are key problems in the bioproduction of high value-added conjugated linoleic acid (CLA). To improve the solubility of recombinant PAI, six chaperone proteins were coexpressed with PAI. Introduction of GroELS proteins dramatically improved the PAI solubility from 29% to 97%, with increased activity by 57.8%. Combined expression of DnaKJ-GrpE and GroELS proteins increased the activity by 11.9%. In contrast, coexpression of DnaKJ-GrpE proteins significantly reduced the activity by 57.4%. Plasmids pTf16 harboring the tig gene and pG-Tf2 containing the tig and groEL-groES genes had no visible impact on PAI expression. The lytic protein E was then introduced into the recombinant Escherichia coli to develop a cell autolysis system. A 35% activity of total intracellular PAI was released from the cytoplasm by suspending the lysed cells in distilled water. The PAI recovery was further improved to 81% by optimizing the release conditions. The lipase from Rhizopus oryzae was also expressed in E. coli, with an extracellular activity of 110.9 U/ml. By using the free PAI and lipase as catalysts, a joint system was established for producing CLA from sunflower oil. Under the optimized conditions, the maximum titer of t-10,c-12-CLA reached 9.4 g/l. This work provides an effective and low-cost strategy to improve the solubility and recovery of the recombinant intracellular PAI for further large-scale production of CLA.

Fear of Falling, Depression, Physical Fitness and Physical Activity among Community Dwelling Elders (지역사회 노인의 신체활동도와 낙상 두려움, 우울, 신체기능)

  • Lee, Young-Hee;Choi, Mi-Kyoung
    • Korean Journal of Adult Nursing
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    • v.23 no.4
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    • pp.351-362
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    • 2011
  • Purpose: This study was designed to examine fear of falling, depression, physical fitness, and physical activity and further to identify the factors that predict physical activity among community dwelling elders. Methods: This study was a cross-sectional descriptive survey. Participants were 153 community dwelling elders from G city. Data were collected using structured questionnaires and were analyzed using descriptive statistics, ${\chi}^2$-test, t-test, ANOVA, and multinominal logistic regression analysis. Results: Activity levers were coded as inactive, minimal activity and enhancing physical active. Thirty-three point three percent reported inactivity, forty-seven point seven percent reported minimal activity and nineteen percent reported health enhancing physical activity. There were significant differences in physical activity relative to gender, age, falling experience, perceived health, and living situation. Further, there was significant difference in fear of falling, depression, and physical fitness by physical activity. For instance, Fear of falling (OR=1.04, p=.014) was a significant predicting factor for physical activity, In contrast for the enhancing physical active the variables of gender (OR=0.28, p=.046), age (OR=0.86, p=.021), perceived health (fair: OR=13.61, p=.006), fear of falling (OR=1.04, p=.026), and two-minute step (OR=1.04, p=.049) were significant. Conclusion: The results of this study indicate that physical activity intervention programs are needed to increase physical activity for community dwelling elders. Physical activity intervention programs should be developed and evaluated.

The Effects of Internal Polity on Commitment and Relationship Performance between Franchisors and Franchisees (프랜차이즈 본부와 가맹점간의 내부정치가 결속 및 관계성과에 미치는 영향)

  • Cho, Hyun-Jin
    • Journal of Distribution Research
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    • v.10 no.2
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    • pp.27-47
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    • 2005
  • This study is basically focused on the relationship between the franchisors and franchisees. The goal of this study is mainly to inquire the variables of relationship characteristics affecting the commitment which lies in internal polity, and secondly to comprehensively analyze the performance resulting from commitment and examine the efficient alternatives onto relationship management. The practical methodology using in this study has been done in a national representing food franchise system. This study has been resulted in following: First, the variables that show significantly to the commitment are noncoercive influential strategy, dependence, cooperation, and goal divergence. In the contrast the coercive influential strategy hasn't showed significantly; Second, the result has showed that the commitment when it would be related with performance furthered the financial performance and role performance; and. therefore, we finally conclude that it would be more important to make lots of efforts of establishing the win-win relationship through the long-term commitment between the franchisor and franchisee in order to develop the more effective relationship of the franchise system.

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High Temperature Creep Characteristics Evaluation for Degraded Heat Resistance Steel of Power Plant by Mini-Specimen (미소시험편에 의한 재질열화된 내열강의 고온 크리프 특성 평가)

  • Lyu, Dae-Young;Baek, Seung-Se;Yu, Hyo-Sun
    • Korean Journal of Materials Research
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    • v.13 no.7
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    • pp.429-435
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    • 2003
  • In this study the new creep test using miniaturized specimen(10${\times}$10${\times}$0.5 ㎣) was performed to evaluate the creep characteristics for degraded materials of 2.25Cr-1Mo steel. For this creep test, the artificially aged materials for 330 hrs and 1820hrs at $630^{\circ}C$ were used. The test temperatures applied for the creep deformation of miniaturized specimens was X$630^{\circ}C$ and the applied loads were between 45 kg∼80 kg. After creep test, macro- and microscopic observation were conducted by the scanning electron microscope(SEM). The creep curves depended definitely on applied load and microstructure and showed the three stages of creep behavior like uniaxial tensile creep curves. The load exponents of virgin, 330 hrs and 1820 hrs materials based on creep rate showed 14.8, 9.5 and 8.3 at $550^{\circ}C$ respectively, The 1820 hrs material showed the lowest load exponent and this behavior was also observed in the case of load exponent based on creep rupture time. In contrast to virgin material which exhibited fined dimple fractography, a lot of carbides like net structure and voids were observed on the fractography of degraded materials.

Chemo-mechanical Analsis of Bifunctional Linear DGEBA/Linear Amine Resin Casting Systems (DGEBA/선형 아민경화제의 주쇄에 포함된 질소 및 탄소원자 개수에 따른 물성 변화 연구)

  • 명인호;정인재;이재락
    • Polymer(Korea)
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    • v.24 no.2
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    • pp.201-210
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    • 2000
  • To determine the effect of chain length of linear amine curing agents on the thermal and mechanical properties, standard epoxy resin, diglycidyl ether of bisphenol A (DGEBA) was cured with diethylenetriamine (DETA), triethylenetetraamine (TETA) and tetraethylenepentaamine (TEPA) in a stoichiometrically equivalent ratio. From this work, the effect of linear amine curing agents on the thermal and mechanical properties was significantly influenced by chain length of curing agents. In contrast, the results showed that the DGEBA/DETA system had higher values than the DGEBA/TETA and DGEBA/TEPA system in the density, shrinkage (%), thermal expansion coefficient, tensile modulus, and flexural strength. Whereas the DGEBA/DETA cure system had lower values than the DGEBA/TETA and DGEBA/TEPA cure system in the maximum exothermic temperature, conversion (%), and T$_{g}$. These findings imply that the differences in the maximum conversion about the chain length of curing agents affect the thermal and mechanical properties.s.

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Laser lithography system for the fabrication of optical waveguides (광도파로 소자 제작을 위한 레이저 리소그래피 장치)

  • Park, K. H.;Byun, Y. T.;Kim, M. W.;Kim, S. H.;Choi, S. S.;Cho, W. R.;Park, S. H.;Kim. U.
    • Korean Journal of Optics and Photonics
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    • v.8 no.2
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    • pp.169-173
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    • 1997
  • Most conventional lithography systems have been oriented to fabricate electronic devices. Therefore, it is not so easy to fabricate large aspect ratios of waveguide patterns with those systems. When considering costs and efficiencies, a laser lithography system provides number of benefit in realizing waveguide patterns. However, because the conventional laser lithography system could make only positive tone masks, it is inconvenient in determining the direction of the waveguide. A simple and reliable technique to produce negative tone masks was developed by using the laser beam writing. This technique was not sensitive to environmental situations such as dust, vibration, intensity variation. Making use of the technique a variety of device patterns such as Y-branch, directional coupler, and highly smooth S-shape bend could be successfully fabricated with a good contrast.

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Analyzing the Time Use of Rural Daily Life on Farm Couple (농업인 부부의 생활시간 조사 분석)

  • Choi, Yoon-Ji;Gim, Gyung-Mee;Lee, Jin-Young;Kang, Kyung-Ha
    • Journal of Agricultural Extension & Community Development
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    • v.14 no.1
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    • pp.231-247
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    • 2007
  • The purposes of this study were to analyze the structure of time use in farm households, and to compare the time use structure of women farmer with that of their husbands. The data for this study were collected from 276 farm households, selected from 8 provinces in the country. The data were collected at two times of farming season and off-farming season and classified as farm labor and household labor by labor types. SPSS(ver 12.0) statistical package was utilized to analyze the data, and t-test was performed for this study. The major findings are as follows; 1) In the case of work directly related to farming, husband's working hour was significantly longer than that of wife during the farming and off-farming season. In contrast with wife's household working hour was significantly longer than that of husband during both seasons. 2) There existed a severe work time imbalance between wife and husband during the-farming season. Based on the findings of this study, the following implications could be drawn to promote efficient labor and equal labor sharing. First, the consciousness has to be changed because the impartial labor sharing roles. We have to develope many programs to break these fixed ideas. And these programs have to be included to educational course and be instructed continuously. Second, the role of wife that household and farming work is important and will be magnified in the future.

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