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Preservative Efficacies according to the Composition of 1, 3-Butylene Glycol and Alkane Diols in Cosmetics (화장품에서 1,3-부틸렌 글라이콜 및 알칸디올계 조성에 따른 방부력에 관한 연구)

  • Suh, Ji Young;Yun, Mid Eum;Lee, Ye Seul;Xuan, Song Hua;Park, Dong Soon;Park, Soo Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.44 no.4
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    • pp.363-373
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    • 2018
  • In recent years, parabens used as preservatives in cosmetics have become a problem of human safety. Therefore, in this study, we tried to evaluate the preservative efficacy of 1,3-butylene glycol, 1,2-hexanediol, and 1,2-pentanediol as a preservative system to replace parabens. 1,3-Butylene glycol was added to cosmetic creams at a concentration of between 5 and 25%. The preservative efficacy of 1,3-butylene glycol was determined using a M-3 challenge test, as recommended by the Personal Care Products Council (formally CTFA). The alkane diols, such as 1,2-hexanediol and 1,2-pentanediol, were assessed in a similar manner. An evaluation of the preservative efficacy of 1,3-butylene glycol revealed that it was effective against all tested microbial strains at a concentration of 25%. We also investigated the efficacy of combinations of 0.3% phenoxyethanol and 0.1% ethylhexylglycerin. Finally, we tested the alkane diols, including 1,2-hexanediol and 1,2-pentanediol, as an alternative to the preservative 0.3% phenoxyethanol. Both 1% 1,2-hexanediol and 1% 1,2-pentanediol demonstrated preservative efficacy. Taken together, our study demonstrated that the formulation of 25% 1,3-butylene glycol and 0.1% ethylhexylglycerin, 1% 1,2-hexanediol, and 1% 1,2-pentanediol had the best preservative efficacy of the compositions tested. Thus, this study suggests that the formulation is a possibility of substituting parabens preservatives, which has been used in cosmetics and has become a safety issue.

A Study on Technological Thinking Disposition of the Specialized and Meister High School Students (특성화 및 마이스터 고등학교 학생들의 기술적 사고성향 연구)

  • Choi, Won-Sik
    • 대한공업교육학회지
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    • v.44 no.1
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    • pp.94-113
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    • 2019
  • This study has been performed for the purpose of providing the basic pedagogical resources to the specialized and meister high school related educational settings in either constructing educational contents suitable for the students'technological thinking disposition or fortifying the disposition required for the students.. A tool of secured validity and reliability has been used to test technological thinking disposition for the specialized and Meister high school students. Followings are the major results of the survey analysis for the subjects. 1. Technological thinking disposition with the most component ratio for the specialized & meister high school was turned out to be Technological Operating Disposition(TOD). The second most was Technological Planning and Reflecting Disposition(TPRD). Technological Curiosity Disposition(TCD), Technological Problem Identifying and Resolving Disposition (TPIRD), Technological Analyzing Disposition(TAD), Technological Creativity and Expressing Disposition(TCED) were in sequence. 2. In comparing the technological disposition of specialized high school students with that of meister high school students, the statistical test showed no evidence for the difference between the two group. 3. Statistical comparison test for the gender difference in technological thinking disposition has also been performed for the students of specialized and meister high school. The result showed that the magnitude of difference between the component ratio of TCD and TPIRD for the boy students was bigger than that for the girl students. In the TPRD, the component ratio for the disposition of the girl students was bigger than that of the boy students on the other hand. 4. For the comparison test of the technological thinking disposition between boys and girls only for the specialized high school students, the results showed the same different component ratio results as the results of the test for the specialized and meister high school students. 5. For the gender difference of meister high school student for the technological thinking disposition, there was no statistical evidence supporting the difference.

A Study on the Records Management for the National Assembly Members (국회의원 기록관리 방안 연구)

  • Kim, Jang-hwan
    • The Korean Journal of Archival Studies
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    • no.55
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    • pp.39-71
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    • 2018
  • The purpose of this study is to examine the reality of the records management of the National Assembly members and suggest a desirable alternative. Until the Public Records Management Act was enacted in 1999, the level of the records management in the National Assembly was not beyond that of the document management in both the administration and the legislature. Rather, the National Assembly has maintained a records management tradition that systematically manages the minutes and bills since the Constitutional Assembly. After the Act was legislated in 2000, the National Assembly Records Management Regulation was enacted and enforced, and the Archives was established in the form of a subsidiary organ of the Secretariat of the National Assembly, even though its establishment is not obligatory. In addition, for the first time, an archivist was assigned as a records and archives researcher in Korea, whose role is to respond quickly in accordance with the records schedule of the National Assembly, making its service faster than that of the administration. However, the power of the records management of the National Assembly Archives at the time of the Secretariat of the National Assembly was greatly reduced, so the revision of the regulations in accordance with the revised Act in 2007 was not completed until 2011. In the case of the National Assembly, the direct influence of the executive branch was insignificant. As the National Assembly had little direct influence on the administration, it had little positive influence on records management innovation under Roh Moo-Hyun Administration. Even within the National Assembly, the records management observed by its members is insignificant both in practice and in theory. As the National Assembly members are excluded from the Act, there is no legal basis to enforce a records management method upon them. In this study, we analyze the records management problem of the National Assembly members, which mainly concerns the National Assembly records management plan established in the National Archives. Moreover, this study proposes three kinds of records management methods for the National Assembly members, namely, the legislation and revision of regulations, the records management consulting of the National Assembly members, and the transfer of the dataset of administrative information systems and websites.

A Study on the Necessity Verification of Convex Probe Disinfection (Convex Probe 소독 필요성 검증에 관한 연구)

  • Choi, Kwan-Yong;Yoo, Se-jong;Lee, Jun-ho;Hong, Sung-Yong
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.193-200
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    • 2019
  • The study was conducted surveying ultrasound room workers on hospital infection awareness in Daejeon and Choong-chunng region. The contamination of ultrasonic probes used in clinical trials was measured using ATP, and the results were verified after using 70% alcohol sterilization. It was measured on the group's general characteristics and the specific categories such as academic background, job type, having professional certificate and infection education. After the examination, the gel removal and method, disinfection status of the probe and variable correlation analysis were performed to analyze the recognition of the ultrasonic probe disinfection. After examination in ultrasound room, it was found that towels were used the most for cleaning, and the gel container was not replaced for more than three months. After 70% alcohol disinfection, ATP contamination was reduced from $1055.4{\pm}944.2$ to $133.5{\pm}93.2$ and the result was analyzed to be statistically significant.(${\rho}<0.01$) The found bacteria were CNS, Gram positive bacillus, and Micrococcus specs. In order to solve this problem, 70% alcohol sterilization was applied and the bacteria were not detected after the treatment. The research shows that regular training on infection control and efforts to prevent infection are necessary, and that 70% alcohol is effective in disinfect the bacteria. Therefore, the medical institution should provide active hospital infection control education to improve the awareness of hospital infection among workers and contribute to the prevention of patient infection. It is also understood that proper use of the results of this study will help prevent infection by means of ultrasonic probes.

Study on Standardization of the Environmental Impact Evaluation Method of Extremely Low Frequency Magnetic Fields near High Voltage Overhead Transmission Lines (고압 가공송전선로의 극저주파자기장 환경영향평가 방법 표준화에 관한 연구)

  • Park, Sung-Ae;Jung, Joonsig;Choi, Taebong;Jeong, Minjoo;Kim, Bu-Kyung;Lee, Jongchun
    • Journal of Environmental Impact Assessment
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    • v.27 no.6
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    • pp.658-673
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    • 2018
  • Social conflicts with extremely low frequency magnetic field(ELF-MF) exposures are expected to exacerbate due to continued increase in electric power demand and construction of high voltage transmission lines(HVTL). However, in current environmental impact assessment(EIA) act, specific guidelines have not been included concretely about EIA of ELF-MF. Therefore, this study conducted a standardization study on EIA method through case analysis, field measurement, and expert consultation of the EIA for the ELF-MF near HVTL which is the main cause of exposures. The status of the EIA of the ELF-MF and the problem to be improved are derived and the EIA method which can solve it is suggested. The main contents of the study is that the physical characteristics of the ELF-MF affected by distance and powerload should be considered at all stages of EIA(survey of the current situation - Prediction of the impacts - preparation of mitigation plan ? post EIA planning). Based on this study, we also suggested the 'Measurement method for extremely low frequency magnetic field on transmission line' and 'Table for extremely low frequency magnetic field measurement record on transmission line'. The results of this study can be applied to the EIA that minimizes the damage and conflict to the construction of transmission line and derives rational measures at the present time when the human hazard to long term exposure of the ELF-MF is unclear.

Feed Value and Yield Potential of Main Whole-Crop Silage Rice Cultivars with Harvesting Time in the Central Plains of Korea (중부 평야지에서 사료용 벼 주요품종의 수확시기 별 사료가치 및 수량성)

  • Ahn, Eok-Keun;Won, Yong-Jae;Park, Hyang-Mi;Jung, Kuk-Hyun;Hyun, Ung-Jo
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.63 no.4
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    • pp.294-303
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    • 2018
  • To set an optimal harvest time for five main whole-crop silage (WCS) rice cultivars, Nokyang (Ny), Mogwoo (Mw), Mogyang (My), Nokwoo (Nw) and Yeongwoo(Yw), based on feed value and dry matter yield, we analyzed water content (WC), feed values such as percent crude protein (CP), crude fat (CF), crude ash (CA), neutral detergent fiber (NDF), acid detergent fiber (ADF), estimated total digestible nutrients (TDN), and calculated their dry matter yield (DMY). These parameters were estimated at the booting stage and every 10 days from start of heading to 45 days after heading (DAH) to identify the optimal harvest time for these rice varieties. In all varieties, except Ny, the WC was about 65% on the $30^{th}$ DAH. In terms of WC, it is judged that there would be no major problem in preparing high quality silage when harvested between 20~30 DAH for Ny and about 30 days for the other cultivars. The CP and CA decreased significantly as the harvest time was delayed in all varieties (p<0.05). However, the CF in the tested varieties generally declined as DAH increased, and then increased again(p<0.05). The decrease in ADF and NDF was significantly different from the booting stage to 45 DAH in all varieties (p<0.05) and the estimated TDN increased gradually in all varieties as the harvest time was delayed. The TDN of all varieties, except Nw, was over 70% around 30 DAH. As harvest time was delayed, the DMY for all WCS rice increased significantly (p<0.05). The maximum DMY for each cultivar was observed at 45 DAH, however, no significant difference (p<0.05) was seen after 40 DAH for Ny and Yw, 30 DAH for Mw and Nw, and 20 DAH for My. Considering these results and others factors such as lodging, shattering, digestibility of grains, conversion of eating rice, etc., the optimal harvest time for silage use of all WCS rice tested was generally the yellow ripening stage, at about 30 DAH (30~40 DAH for Ny and Mw, and 30 DAH for My, Nw and Yw).

Comparison of Doses of Single Scan PBS and Layered Rescanning PBS Using Moving Phantom in Proton Therapy (양성자 치료에서 Moving Phantom을 이용한 Single Scan PBS와 Layered Rescanning PBS의 선량비교)

  • Kim, Kyeong Tae;Kim, Seon Yeong;Kim, Dae Woong;Kim, Jae Won;Park, Ji Yeon;Jeon, Sang Min
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.1
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    • pp.43-49
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    • 2019
  • Purpose : We apply the Layered Rescanning PBS designed to complement the Pencil Beam Scanning(PBS), which is vulnerable to moving organs with the Moving Phantom, and compare the homogeneity with the single scan PBS. Methods and materials: Matrix X (IBA, Belgium) and Moving Phantom (standard imaging, USA) were used. A dose of 200 cGy was measured in the AP direction on a hypothetical tumor $10{\times}10{\times}5cm$. The plan type was planned as 4 kinds of sinlge scan PBS, rescan number 4, 8, 12 times. Were measured three times for each types. During the measurement, the respiratory cycle of the Moving Phantom was generally set to 4 seconds per cycle, and the movement radius in the S-I direction was set to 2 cm. In addition, beam on time was measured. Results : The mean values of $D_{max}$ in the PTV were $246.47{\pm}18.8cGy$, $223.43{\pm}8.92cGy$, and $222.47{\pm}7.7cGy$, $213.9{\pm}6.11cGy$ and the mean values of $D_{min}$ were $165.53{\pm}4.32cGy$, $173.13{\pm}11.94cGy$, $184.13{\pm}8.04cGy$, $182.67{\pm}4.38cGy$ and the mean values of $D_{mean}$ $192.77{\pm}6.98cGy$, $196.7{\pm}4.01cGy$, $198.17{\pm}4.96cGy$, $195.77{\pm}3.15cGy$ respectively. As the number of rescanning increased, the Homogeneity Index converged to 1. The beam on time was measured as 2:15, 3:15, 4:30, 5:37 on average. In the measurement process, in the low dose layer of the MU, the problem was found that it was not rescanned as many times as the set number of rescan. Conclusions : In the treatment of tumors with long-term movements, the application of layered rescanning PBS showed a more uniform dose distribution than single scan PBS. And as the number of rescan increase, the distribution of homogeneity is uniform. Compared with single scan plan and 12 rescan plan, HI value was improved by 0.32. Further studies are expected to be applicable to patients who can not be treated with respiratory synchronous radiation therapy.

A Study on the Guidelines on the Insertion of Metal Stiffeners in the Restoration of Stone Cultural Heritages (석조문화재 복원을 위한 금속보강재 매입방법 표준화 연구)

  • Lee, Dong-sik;Kim, Hyun-yong;Kim, Sa-dug;Hong, Seong-geol
    • Korean Journal of Heritage: History & Science
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    • v.46 no.3
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    • pp.212-228
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    • 2013
  • Stone cultural heritages are repaired by the use of metal stiffeners. The problem is that this type of repair has been based on the experience of workers without specific guidelines and has caused various problems. This is to suggest the structural reinforcement and behavioral characteristics of metal rods to minimize the secondary damage of materials and have the specimens tested and verified to establish the guidelines on how to insert metal stiffeners. When only epoxy resin is applied to the cut surface, only 70% of the properties of the parent material are regenerated and it is required to structurally reinforce the metal stiffener for the remaining 30%. The metal rod is under the structural behavior after the brittle failure of stone material and the structural behavior does not occur when the metal stiffener is below 0.251%. When it accounts for over 0.5%, it achieves structural reinforcement, but causes secondary damage of parent materials. The appropriate ratio of metal stiffener for the stone material with the strength of $1,500kgf/cm^2$, therefore, should be between 0.283% and 0.377% of the cross section of attached surface to achieve reversible fracture and ductility behavior. In addition, it is more effective to position the stiffeners at close intervals to achieve the peak stress of metal rod against bending load and inserting the stiffener into the upper secions is not structurally supportive, but would rather cause damage of the parent material. Thus, most stiffeners should be inserted into the lower part and some into the central part to work as a stable tensile material under the load stress. The dispersion effect of metal rods was influenced by the area of reinforcing rods and unrelated to their diameter. However, it ensures stability under the load stress to increase the number of stiffeners considering the cross section adhered when working on large-scale structures. The development length is engineered based upon the diameter of stiffener using the following formula: $l_d=\frac{a_tf_y}{u{\Sigma}_0}$. Also, helically-threaded reinforcing rods should be used to perform the behaviors as a structural material.

Selective Algicidal Effects of a Newly Developed GreenTD against Red Tide Harmful Alga (GreenTD 물질을 이용한 유해 적조 발생 종의 선택적 살조능 평가)

  • Lee, Minji;Shin, Juyong;Kim, Jin Ho;Lim, Young Kyun;Cho, Hoon;Baek, Seung Ho
    • Korean Journal of Environmental Biology
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    • v.36 no.3
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    • pp.359-369
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    • 2018
  • Harmful algal blooms (HABs) are a serious problem for public health and fisheries industries, thus there exists a need to investigate the possible ways for effective control of HABs. In the present study, we investigated the algicidal effects of a newly developed GreenTD against the HABs (Chattonella marina, Heterosigma akashiwo, Cochlodinium polykriokides, and Heterocapsa circularisquama) and non-HABs (Chaetoceros simplex, Skeletonema sp. and Tetraselmis sp.), which is focused on the different population density and concentration gradients of algicidal substances. The time series viability of target alga was assessed based on the activity of Chl. a photosynthetic efficiency in terms of $F_v/F_m$, and in vivo fluorescence (FSU). Effective control of Raphidophyta, C. marina and H. akashiwo was achieved at a GreenTD concentration of $0.5{\mu}gL^{-1}$ and $0.2{\mu}gL^{-1}$, respectively, and regrowth of both the species was not observed even after 14 days. The inhibitory ratio of the dinoflagellate, C. polykriokides was more than 80% at $0.2{\mu}gL^{-1}$ of GreenTD. H. circularisquama was constantly affected in the presence of $0.2{\mu}gL^{-1}$ of GreenTD in the high- and low-population density experimental groups. On the other hand, diatoms, C. simplex, and Skeletonema sp. were not significantly affected even in the presence of $0.2{\mu}gL^{-1}$ of GreenTD and exhibited re-growth activity with the passage of incubation time. In particular, green alga Tetraselmis sp. remained unaffected even in the presence of the highest concentration of GreenTD ($1.0{\mu}gL^{-1}$), implying that non-HABs were not greatly influenced by the algicidal substances. As a result, the algicidal activity of GreenTD on the harmful and nonharmful algae was as follows: raphidophyte>dinoflagellates>diatoms>green alga. Consequently, our results indicate that inoculation of GreenTD substances into natural blooms at a threshold concentration ($0.2{\mu}gL^{-1}$) can maximize the algicidal activity against HABs species. If we consider the dilution and diffusion rate in the field application, it is hypothesized that GreenTD will demonstrate economic efficiency, thus leading to effective control against the target HABs in the closed bay.

Review on the Implementation Process and Achievement of ICH Safeguarding System (무형문화재 보호제도의 이행과정과 그 성과에 관한 검토)

  • Lee, Jae Phil
    • Korean Journal of Heritage: History & Science
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    • v.44 no.4
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    • pp.18-41
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    • 2011
  • The Safeguarding of Intangible Cultural Heritage in Korea has begun since1962 when the Cultural Properties Protection Act was established. Korean ICH Safeguarding system is initially derived from Cultural Properties Protection Act in Japan. Japan has started Important ICH Designation System in 1954 to concede the skills and artistic talents holders, thus it could implement the multilateral system management for adopting different ICH protection systems such as Important Intangible Folklore Properties, Selection and Preservation Techniques, and Documenting Records. However, Korea has solely adopted Important ICH Designation System since Cultural Properties Protection Act was introduced. Korean ICH Safeguarding System represented by the Certification System of ICH Skill Holders is to ensure skills and artistic holders who perform the elements of Intangible Cultural Heritage, and manage the safeguarding of intangible cultural heritage in order to let the skills and artistic holders instruct inheritors. As a result, it could build up the internal foundation for the diffusion of inheritors and established the related organizations. However, the inheritor-centered protection system has caused many problems as it is being lasted for more than fifty years. Fragmented designation measures, the cultural power of skill holders, and the research and evaluation methods have pointed out the difficulties of safeguarding and preservation measures of ICH. Moreover,the legitimacy of safeguarding system related in the authenticity of transmission in ICH has emerged to review the safeguarding system of ICH with diverse viewpoints. Therefore, this paper will review the implementation process and achievement of ICH safeguarding system to examine the problem and causes of the safeguarding system. The conference records of Cultural Property Association and articles of cultural properties policies directors, Cultural Property Association members, and professional experts are being used for the initial materials of this paper, and it is examined for the contents of designation system of Important Cultural Heritage, rather than overall cases. Thus such problems the limitation of expansion in ICH lists as inheritor-centered designation system, hierarchical and exclusive transmission system, inappropriate concept of archetype as the principle of ICH transmission are derived from the root of Important ICH designation system. Thus this paper demonstrates that this system must be revised for the expansion of ICH safeguarding system in Korea and points out multilateral protection system should be established as well as Certification System of Important ICH skill holders.