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Optimization of Medium for the Carotenoid Production by Rhodobacter sphaeroides PS-24 Using Response Surface Methodology (반응 표면 분석법을 사용한 Rhodobacter sphaeroides PS-24 유래 carotenoid 생산 배지 최적화)

  • Bong, Ki-Moon;Kim, Kong-Min;Seo, Min-Kyoung;Han, Ji-Hee;Park, In-Chul;Lee, Chul-Won;Kim, Pyoung-Il
    • Korean Journal of Organic Agriculture
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    • v.25 no.1
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    • pp.135-148
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    • 2017
  • Response Surface Methodology (RSM), which is combining with Plackett-Burman design and Box-Behnken experimental design, was applied to optimize the ratios of the nutrient components for carotenoid production by Rhodobacter sphaeroides PS-24 in liquid state fermentation. Nine nutrient ingredients containing yeast extract, sodium acetate, NaCl, $K_2HPO_4$, $MgSO_4$, mono-sodium glutamate, $Na_2CO_3$, $NH_4Cl$ and $CaCl_2$ were finally selected for optimizing the medium composition based on their statistical significance and positive effects on carotenoid yield. Box-Behnken design was employed for further optimization of the selected nutrient components in order to increase carotenoid production. Based on the Box-Behnken assay data, the secondary order coefficient model was set up to investigate the relationship between the carotenoid productivity and nutrient ingredients. The important factors having influence on optimal medium constituents for carotenoid production by Rhodobacter sphaeroides PS-24 were determined as follows: yeast extract 1.23 g, sodium acetate 1 g, $NH_4Cl$ 1.75 g, NaCl 2.5 g, $K_2HPO_4$ 2 g, $MgSO_4$ 1.0 g, mono-sodium glutamate 7.5 g, $Na_2CO_3$ 3.71 g, $NH_4Cl$ 3.5g, $CaCl_2$ 0.01 g, per liter. Maximum carotenoid yield of 18.11 mg/L was measured by confirmatory experiment in liquid culture using 500 L fermenter.

A Study on Oxygen Reduction Reaction of PtM Electrocatalysts Synthesized by a Modified Polyol Process (수정된 폴리올 방법을 적용하여 합성한 PtM 촉매들의 산소환원반응성 연구)

  • Yang, Jongwon;Hyun, Kyuwhan;Chu, Cheunho;Kwon, Yongchai
    • Applied Chemistry for Engineering
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    • v.25 no.1
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    • pp.78-83
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    • 2014
  • In this research, we evaluated the performance and characteristics of carbon supported PtM (M = Ni and Y) alloy catalysts (PtM/Cs) synthesized by a modified polyol method. With the PtM/Cs employed as a catalyst for the oxygen reduction reaction (ORR) of cathodes in proton exchange membrane fuel cells (PEMFCs), their catalytic and ORR activities and electrical performance were investigated and compared with those of commercial Pt/C. Their particle sizes, particle distributions and electrochemically active surface areas (EAS) were measured by TEM and cyclic voltammetry (CV), while their ORR activity and electrical performance were explored using linear sweeping voltammetries with rotating disk electrodes and rotating ring-disk electrodes as well as PEMFC single cell tests. TEM and CV measurements show that PtM/Cs have the compatible particle size and EAS with Pt/C. When it comes to ORR activity, PtM/C showed the equivalent or better half-wave potential, kinetic current density, transferred electron number per oxygen molecule and $H_2O_2$ production(%) to or than commerical Pt/C. Based on results gained by the three electrode tests, when the PEMFC single cell tests were carried out, the current density measured at 0.6 V and maximum power density of PEMFC single cell adopting PtM/C catalysts were better than those adopting Pt/C catalyst. It is therefore concluded that PtM/C catalysts synthesized by modified polyol can result in the equivalent or better ORR catalytic capability and PEMFC performance to or than commercial Pt/C catalyst.

A Study on the Information Gathering Function of Research and Development Laboratories Established within Industrial Firms (산업체 부설연구소의 정보기능에 관한 연구)

  • Cho In Sook
    • Journal of the Korean Society for Library and Information Science
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    • v.16
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    • pp.281-327
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    • 1989
  • This dissertation is presented in two major parts. The first part presented in Chapter 3 attempts to verify the major hypothesis of the present study that the research and development laboratories(hereafter referred to R&D laboratories), establishd withine industrial firms to develop new technologies needed for their own industrial activities, may have another but very important functions to bring information on the externally generated technologies to attention of their respective management decision makers, eventually resulting in the transfer of technology; and such information functions of the R&D laboratories may be better performed by well-organised laboratories than by poorly-organised ones. The second part presented in Chapters 4, 5, 6 and 7 discusses, after the preceding hypotheses has been verified, some desirable situations of the R&D laboratories in facilitating the flow of information on new technologies developed in the world into their industrial firms, centering on the organisational positions and the major fields of interest of the person in charge of the R&D centers, services of the library and technological information office supporting the R&D laboratories, and frequencies of direct contacts of research and development workers with experts in the world and of participation in various conferences, seminars, workshops, exhibitions, etc. Now that there is no recognised instrument and method available for direct measurement of volume of technological information transfered into a particular industrial firm, the number of technologies introduced into a given firm is employed in the present study as an analogous parametre indicating volume of technological information transfered into the firm during a particular period of time. A logical attempt to justify the use of the indirect paramentre is made in Chapter two. vidences needed to verify the hypotheses of the present study are collected through the various publications of the Korea Industrial Research Institutes and other agencies and institutions related to industrial research activities, and through responses to the questionnaire posted to a sample of the 66 R&D laboratories on 6 May 1987 and returned by 30 August of the same year. Some findings and conclusions made in the study are summarised as follows: (1) More information on externally developed technologies flows into the industrial firm with a R&D laboratory of its own than into the industrial firm without one, and naturally, more chances of transfer of technologies are given to the former than to the latter (see 3. 2) (2) After establishing an R&D laboratory, more technological information flows into the industrial firm than before establishing one (see 3. 3) (3) More technological information flows into the industrial firm with a well-organised R&D laboraory than into the firm with a poorly-organised one (see 3. 4) (4) More technological information flows into the ndustrial firm where the director of its R&D laboratory has status qualified to participate in the highest managerial decision making processes of the firm than into the industrial firm where the director does not have such status (see 4. 2) (5) More technological information flows into the industrial firm where the director of R&D laboratory does not hold other positions within the firm than into the industrial firm where the director holds other positions (see 4.3) (6) There is evidence showing that quantities of technological information transfered into industriali firms vary with the case that the major background of the director of the R&D laboratory is the same as the main field of R&D activities of his or her laboratery, the case that the director's background is partly related to the field of R&D activities of the laboratory, and the case that the director's major background is different from the field of R&D activities of the laboratory (see 4.4) (7) More technological information flows into the industrial firm with the director of its R&D laboratory appointed from among professional research and development workers than into the industrial firm with the director of its R&D laboratory appointed from among general managers (see 4.5) (8) More technological information flows into the industrial firm with its R&D laboratory which has established a library service unit within its own jurisdiction than into the industrial firm with its R&D laboratory which has established a library service unit within its own jurisdiction than into the industrial firm with its R&D laboratory which uses a library within the firm but outside the laboratory (see 5. 1) (9) More echnological information flows into the industrial firm with a technological information office of its own than into the industrial firm without such an office (see 5. 2) (10) More technological information flows into the industrial firm with a large research and development staff in its R&D laboratory than into the industrial firm with a small staff in its R&D laboratory (see 5. 2) (11) More technological information flows into the industrial firm with its R&D laboratory whose staff members more frequently contact experts in the conferences, seminars, symposiums, and workshops held in foreign countries and novelties in the world's major exhibitions than into the industrial firm with its R&D laboratory whose staff members less frequently contact such experts and novelties (see 6. 2 ; 6. 3)

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Evaluation of reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay for detection of infectious hematopoietic necrosis virus (IHNV) (Infectious hematopoietic necrosis virus (IHNV)-검출 Reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) 법의 평가)

  • Kim, Wi-Sik;Jeon, Chan-Hyeok;Kim, Jeong-Ho;Oh, Myung-Joo
    • Journal of fish pathology
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    • v.25 no.3
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    • pp.257-262
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    • 2012
  • A reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) assay was evaluated to monitor infectious hematopoietic necrosis virus (IHNV) from artificially infected rainbow trout Oncorhynchus mykiss. The cumulative mortalities of fish challenged with IHNV at $10^{6.5}\;TCID_{50}$/fish, $10^{5.5}\;TCID_{50}$/fish and $10^{4.5}\;TCID_{50}$/fish were 40%, 0% and 0%, respectively. Dead fish and survivors at 16 and 28 d post-challenge in each group were employed for IHNV detection by RT-LAMP assay and virus isolation using BF-2 cells. IHNV from $10^{4.3}$ to $10^{6.8}\;TCID_{50}/ml$ was isolated from all the dead fish and also detected in all of the examined dead fish by RT-LAMP assay. In survivors at 16 d, 60% (3/5 fish, $10^{2.8}-10^{5.05}\;TCID_{50}/ml$), 20% (1/5 fish, $10^{1.05}\;TCID_{50}/ml$) and 60% (3/5 fish, $10^{1.05}-10^{4.8}\;TCID_{50}/ml$) were found to be IHNV-positive by virus isolation in fish challenged with IHNV at $10^{6.5}\;TCID_{50}$/fish, $10^{5.5}\;TCID_{50}$/fish and $10^{4.5}\;TCID_{50}$/fish, respectively, while 20% (1/5 fish), 0% (0/5 fish) and 20% (1/5 fish) were IHNV-positive by RT-LAMP assay. No IHNV was detected in the survivors at 28 d and control fish. These results indicate that the RT-LAMP assay is useful for detection of IHNV in diseased fish although it is not enough to monitor virus in IHNV-survivors.

Isolation and Characterization of a Marine Bacterium, Pseudomonas sp. YJ-1 with Anti-Methicillin Resistant Staphylococcus aureus Activity (항 Methicillin Resistant Staphylococcus aureus 활성을 가지는 해양미생물 Pseudomonas sp. YJ-1의 분리와 특성)

  • Woo, Ye-Ju;Jeong, Seong-Yun
    • Korean Journal of Environmental Biology
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    • v.35 no.4
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    • pp.694-705
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    • 2017
  • The aim of this study was to isolate and identify marine bacterium with anti-methicillin-resistant Staphylococcus aureus (MRSA) activity, and to purify the anti-MRSA compound, as well as to determine its activity and synergistic effects. Among the marine bacteria isolated in this study, the YJ-1 isolate had the strongest anti-MRSA activity. The YJ-1 isolate was identified on the basis of its biochemical characteristics and an analysis of 16S rRNA gene sequences. The YJ-1 isolate showed over 99.2% homology with Pseudomonas stutzeri, and was designated as a Pseudomonas sp. YJ-1. The optimal culture conditions were $25^{\circ}C$ and initial pH 7.0. For the purification of the anti-MRSA compounds, the YJ-1 was cultured in Pa PES-II medium, and the culture filtrates were extracted by ethyl acetate, hexane, and 80% MeOH. The 80% MeOH fraction was separated by a $C_{18}$ ODS column, silica gel chromatography and a reverse phase HPLC, to yield three anti-MRSA agents, the MR1, MR2, and MR3 compounds. When the MR1 compound of $250{\mu}g\;mL^{-1}$ concentration was applied to the MRSA cells, over 95% of bacterial cells was killed within 48 hr. Compared with vancomycin and ampicillin, the MR1 compound showed significant anti-MRSA activity. In addition, the anti-MRSA activity was increased by dose and time dependent manners. Furthermore, the combination of an MR1 compound with vancomycin produced a more rapid decrease in the MRSA cells than did the MR1 compound alone. Taken together, our results suggest that the Pseudomonas sp. YJ-1 and its anti-MRSA compounds could be employed as a natural antibacterial agent in MRSA infections.

Prefetching based on the Type-Level Access Pattern in Object-Relational DBMSs (객체관계형 DBMS에서 타입수준 액세스 패턴을 이용한 선인출 전략)

  • Han, Wook-Shin;Moon, Yang-Sae;Whang, Kyu-Young
    • Journal of KIISE:Databases
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    • v.28 no.4
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    • pp.529-544
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    • 2001
  • Prefetching is an effective method to minimize the number of roundtrips between the client and the server in database management systems. In this paper we propose new notions of the type-level access pattern and the type-level access locality and developed an efficient prefetchin policy based on the notions. The type-level access patterns is a sequence of attributes that are referenced in accessing the objects: the type-level access locality a phenomenon that regular and repetitive type-level access patterns exist. Existing prefetching methods are based on object-level or page-level access patterns, which consist of object0ids of page-ids of the objects accessed. However, the drawback of these methods is that they work only when exactly the same objects or pages are accessed repeatedly. In contrast, even though the same objects are not accessed repeatedly, our technique effectively prefetches objects if the same attributes are referenced repeatedly, i,e of there is type-level access locality. Many navigational applications in Object-Relational Database Management System(ORDBMs) have type-level access locality. Therefore our technique can be employed in ORDBMs to effectively reduce the number of roundtrips thereby significantly enhancing the performance. We have conducted extensive experiments in a prototype ORDBMS to show the effectiveness of our algorithm. Experimental results using the 007 benchmark and a real GIS application show that our technique provides orders of magnitude improvements in the roundtrips and several factors of improvements in overall performance over on-demand fetching and context-based prefetching, which a state-of the art prefetching method. These results indicate that our approach significantly and is a practical method that can be implemented in commercial ORDMSs.

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Studies on Chronic Mastitis of Dairy Cattle in Taegu-Kyungpook Provinces (대구(大邱).경북지방(慶北地方)에서 문제되는 젖소의 만성(慢性) 유방염(乳房炎)에 관한 연구(硏究))

  • Kim, Bong Hwan;Park, Hoo Yhul;Chang, In Ho
    • Current Research on Agriculture and Life Sciences
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    • v.2
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    • pp.115-121
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    • 1984
  • Some investigations on chronic mastitis in dairy cattle in Taegu-Kyungpook Provinces from the beginning of October, 1984 till the end of August, 1985 were conducted with the particular regard to the causative agents and their drug susceptibility. Milk samples from 83 isolated cases of chronic mastitis cattle were investigated bacteriologically and the causative organisms recovered were examined for their antibiotic susceptibility by using disc diffusion susceptibility technique against the major antibiotics of current veterinary use. Major causative agents involved in chronic mastitis in Taegu-Kyungpook Provinces were in order of prevalence Staphylococcus spp. (48.2 %), Escherichia coli (18.1 %), Candida spp. (10.8 %) and Corynebacterium spp. (8.4 %), Streptococcus agalactiae (3.6 %), Bacillus cereus (3.6 %) and Pseudomonas aeruginosa (2.4 %) were found to be one of the minor agents. The majority of staphylococcal isolates and E. coli were highly resistant to the most antibiotics tested. The percentages of staphylococcal cultures resistant to penicillin, methicillin, lincomycin, novobiocin, ampicillin and tetracycline were 87.2 %, 78.7 %, 68.1 %, 61.7% and 57.4 %, respectively, while the majority of them were susceptible to gentamicin(78.7 %), cephalothin(76.6 %) and chloramphenicol (74.5%). E. coli isolates were found to be highly resistant to streptomycin, cephalothin, tetracycline and ampicillin while the majority of them were susceptible to colistin (83.3 %), gentamicin (77.8 %) and chloramphenicol (66.7 %). Corynebacterium spp. were susceptible to ampicillin, chloramphenicol, erythromycin, gentamicin, oleandomycin and tetracycline although they showed resistance to novobiocin and penicillin. Two cultures of Pseudomonas aeruginosa recovered from mastitis milk were highly resistant to the antibiotics employed in the present study.

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Personal Information Overload and User Resistance in the Big Data Age (빅데이터 시대의 개인정보 과잉이 사용자 저항에 미치는 영향)

  • Lee, Hwansoo;Lim, Dongwon;Zo, Hangjung
    • Journal of Intelligence and Information Systems
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    • v.19 no.1
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    • pp.125-139
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    • 2013
  • Big data refers to the data that cannot be processes with conventional contemporary data technologies. As smart devices and social network services produces vast amount of data, big data attracts much attention from researchers. There are strong demands form governments and industries for bib data as it can create new values by drawing business insights from data. Since various new technologies to process big data introduced, academic communities also show much interest to the big data domain. A notable advance related to the big data technology has been in various fields. Big data technology makes it possible to access, collect, and save individual's personal data. These technologies enable the analysis of huge amounts of data with lower cost and less time, which is impossible to achieve with traditional methods. It even detects personal information that people do not want to open. Therefore, people using information technology such as the Internet or online services have some level of privacy concerns, and such feelings can hinder continued use of information systems. For example, SNS offers various benefits, but users are sometimes highly exposed to privacy intrusions because they write too much personal information on it. Even though users post their personal information on the Internet by themselves, the data sometimes is not under control of the users. Once the private data is posed on the Internet, it can be transferred to anywhere by a few clicks, and can be abused to create fake identity. In this way, privacy intrusion happens. This study aims to investigate how perceived personal information overload in SNS affects user's risk perception and information privacy concerns. Also, it examines the relationship between the concerns and user resistance behavior. A survey approach and structural equation modeling method are employed for data collection and analysis. This study contributes meaningful insights for academic researchers and policy makers who are planning to develop guidelines for privacy protection. The study shows that information overload on the social network services can bring the significant increase of users' perceived level of privacy risks. In turn, the perceived privacy risks leads to the increased level of privacy concerns. IF privacy concerns increase, it can affect users to from a negative or resistant attitude toward system use. The resistance attitude may lead users to discontinue the use of social network services. Furthermore, information overload is mediated by perceived risks to affect privacy concerns rather than has direct influence on perceived risk. It implies that resistance to the system use can be diminished by reducing perceived risks of users. Given that users' resistant behavior become salient when they have high privacy concerns, the measures to alleviate users' privacy concerns should be conceived. This study makes academic contribution of integrating traditional information overload theory and user resistance theory to investigate perceived privacy concerns in current IS contexts. There is little big data research which examined the technology with empirical and behavioral approach, as the research topic has just emerged. It also makes practical contributions. Information overload connects to the increased level of perceived privacy risks, and discontinued use of the information system. To keep users from departing the system, organizations should develop a system in which private data is controlled and managed with ease. This study suggests that actions to lower the level of perceived risks and privacy concerns should be taken for information systems continuance.

Studies on the Energy and Protein Requirement Determination for Broiler Production -4. Effect of Iso-calorie and Different Protein Level on Broiler Production- (Broiler 생산(生産)에 있어서 Energy와 Protein 요구량(要求量) 결정(決定)에 관한 연구(硏究) (제4보(第4報)) -동일(同一)Energy수준(水準)에서의 Protein 수준이 Broiler 생산(生産)에 미치는 영향(影響)-)

  • Kim, Dae Jin;Kim, Young Kil;Ko, Yong Du
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.12 no.4
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    • pp.395-400
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    • 1983
  • The experiment was conducted to study the effect of protein level on weight gain, feed consumption and the efficiencies of feed, energy and protein when the broiler chick was fed the diet of different protein level with the iso-calorie content. The energy and protein level of the basal ration was 3200 kcal and 22.85% for starter period and 3265 Kcal and 18.58% for finisher period, respectively. In order to increase the protein level of the experimental diet, the basal diet was substituted by fish meal by the ratio of 3, 6, 9, and 12%. The male Abor Acre broiler chicks were employed for 8 weeks and the result obtained were as follows. 1. The weekly body weight gain was significantly greater for Diet C than for Diet A and E in the starter period and greater for Diet A than for Diet E in the finisher period (P<0.05). 2. In stater period the feed intake was not affected by the protein level but in finisher period the feed intake for Diet C, D, and E was significantly reduced compared with Diet A. 3. As for feed conversion ratio, Diet C of 1.43 was improved significantly compared with Diet A of 1.58(P<0.05). 4. As the protein level of diet increased, the energy efficiency ratio increased and however, the protein efficiency ratio decreased in starter and finisher period. In conclusion the best performance of broiler is thought to be realized when the protein and energy level was 23% and 3200 Kcal for starter period and 20% and 3250 Kcal for finisher period, respectively.

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Evaluation of TQM(Total Quality Management) of Home Economics Education Department in the University by Students (가정교육과 교사교육의 TQM(Total Quality Management: 총체적 질 관리) 구성요소에 대한 재학생들의 평가)

  • Kim, Sung-Gyo;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.20 no.3
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    • pp.179-200
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    • 2008
  • This study is aimed at contributing to the future development of Home Economics Education Department by suggesting basic data of TQM(Total Qualify Management) for evaluating TQM of Home Economics Education Departmeut in education colleges. A survey was conducted involving all junior(3rd year) students of Home Economics Education Department in education colleges either by making a visit to 3 different schools or by sending it in the mail to 10 different schools. Responding answer-sheets, 302 copies(88.3%) out of 342 copies in total were returned. Finally, we used 285 copies(83.3%) as data for analysis. The results of this study are as follows: In terms of Professional Qualification of Home Economics Teachers, the students had passion for their Home Economics Education and also had a great pride and mission to be future Home Economics teachers. However, their ability proved to be poor and low in presenting a vision for Home Economics, in conducting extra-curricular activities, and the computer skills. In the case of college students, their satisfaction showed an average point 3.15 on a scale of 5. Those students who entered school voluntarily or those who hoped for re-entrance showed more satisfaction than those who entered school with good academic records or those who do not hope for re-entrance into school. In terms of professors' leadership, Students are perceived to choose 'Transactional Leadership' instead of 'Transformational Leadership'. Students', who have higher satisfaction and hopes for re-entrance, perception level about their professors' leadership style showed higher satisfaction than average. The students empowerment level showed average point 3.52, which is considered relatively high. Students at the college where professors majored in Home Economics Education are employed showed higher empowerment level than students at the college with professors who did not major in Home Economics Education. The result of evaluating general demand for renovating of Home Economics Education Dept. showed that: they perceived the "Teacher Education Course" of Home Economics Education Dept. as in need of cultivating practical skills in secondary school. They also said, "Teaching Method" is in great need of renovation. In the case of teaching method, they preferred laboratory work, and practical training. In earning credits, they emphasized the importance of faithfully completing the "Study of Content". For the Subject Matter Education, they required a training course to be set up in the secondary school. Finally they claimed that the teachers and students need to take the initiative in developing a Curriculum of Home Economics Education Dept. Based on the findings mentioned above, I would like to suggest further research on how to adopt and evaluate TQM in Home Economics Education, and faculty-centered evaluation methods. I also would like to suggest to vitalize quality research through the form of narrative research.

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