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A Study on Shaker's Free Design from Fashion (유행(流行)으로부터 자유로운 세이커(Shaker) 디자인에 대한 고찰)

  • Choi, Sung-Woon;Huh, Jin
    • Archives of design research
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    • v.20 no.3 s.71
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    • pp.279-288
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    • 2007
  • Today, design is not free from fashion, which emerges and vanishes temporarily, and aims at equalization. As a result, products quickly become obsolete because of fashion. This means that the span of products is determined by a social concept, which is not clarified, regardless of their functions. Usable products will gradually disappear from us and it will cause serious environmental problems, unless we can find out measures against fashion. As such, it is important to study the characteristics of the shaker's design in this circumstance. The Shaker's community has a distinguishable difference from other general societies. Temporary fashion and misled information cannot interfere with their consciousness. Religion, the life and the principle of design have developed on the same level in their community. Especially, any decoration or the difference of materials is not allowed in shaker's design. It reflects their thinking that all people are equal in the sight of God. Therefore, any decoration for social and economical superiority can not be used. Through this consciousness, they can be free from fashion or decoration. They, also, believe that they can reach perfection through practicality and simplicity. The reason why shaker's design is not disturbed by fashion is that their belief is involved in their design. Consequently, if religious or conscious contents are primarily set up, design can be free from fashion and products can be used for a long time.

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Cell Death Study in Embryonic Stem Cell-derived Neurons and Its Applications (배아줄기세포 유래 신경계세포에서의 세포사멸 연구와 그 응용)

  • Lee, Chul-Sang
    • Development and Reproduction
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    • v.12 no.1
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    • pp.1-8
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    • 2008
  • Specific protocols to increase the differentiation of neuronal cells from embryonic stem (ES) cells have been well established, such as retinoic acid induction and lineage selection of neuronal cells. For the neuropathological studies, ES-derived neurons (ES neurons) must show normal physiological characteristics related to cell death and survival and should be maintained in vitro for a sufficient time to show insults-specific cell death without spontaneous death. When mouse ES cells were plated onto astrocytes monolayer after retinoic acid induction, most ES cells differentiated into neuronal cells, which were confirmed by the presence of specific neuronal markers, and the cultures were viable for at least four weeks. When these cultures were examined for vulnerability to glutamate excitotoxicity, ES neurons were vulnerable to excitotoxic insults mediated by agonist-specific receptors. The vulnerability to excitotoxic death increased with developmental age of ES neurons in vitro. Specific receptors for Neurotrophin and GDNF family ligands were present in ES neurons. GDNF and NT-3 could modulate the survival and excitotoxic vulnerability of ES neurons. The vulnerability and resistance to toxic insults, which are essential requirements of model culture systems for neuropathological studies, make ES neurons to a useful model culture system. Especially ES cell are highly amenable to genetic modification unlikely to primary neuronal cells, which will give us a chance to answer more complicated neurophysiological questions. Recently there was an outstanding attempt to explore the cellular toxicity using human ES cells (Schrattenholz & Klemm, 2007) and it suggested that ES cells could be a new model system for neurophysiological studies soon and go further a large-scale screening system for pharmacological compounds in the future.

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A Study on Migration of Monomers from Kitchen Utensils Including PA, PU, ABS, and Acrylic Resin Plastics (폴리아마이드제 등 조리기구 중 모노머의 이행에 관한 연구)

  • Choi, Jae-Chon;Park, Se-Jong;Park, Geon-Woo;Min, Hye-Kyoung;Yang, Ji-Young;Kim, Meehye
    • Journal of Food Hygiene and Safety
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    • v.30 no.1
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    • pp.81-86
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    • 2015
  • The purpose of our paper was to investigate the migration level of 4,4'-MDA(4,4'-methylenedianiline), 2,4-TDA(2,4-toluenediamine), aniline, acrylonitrile and methylmeth acrylate from plastic cookwares into food simulants and to evaluate the safety of each monomers. The test articles for monomers were PA (polyamide) items for 4,4'-MDA, 2,4-TDA and aniline, PU (polyurethane) items for 4,4'-MDA, ABS (acrylonitrile-butadiene- styrene) items for acrylonitrile, and acrylic resin items for methylmethacrylate. All the article samples of 321 intended for contact with foods were purchased in domestic market. 4,4'-MDA, 2,4-TDA and aniline were analyzed by LC-MS/MS (liquid chromatography -tandem mass spectrometer), acrylonitrile by GC-NPD (gas chromatography-nitrogen phos phorus detector) and methyl methacrylate by GC-FID (gas chromatography-flame ionization detector). The migration level of monomers were within the migration limits of Ministry of Food and Drug Safety (MFDS). As a result of safety evaluation, our results showed that the estimated daily intake (EDI, mg/kg bw/day)s were $2.39{\times}10^{-9}$ and $1.20{\times}10^{-9}$ for 4,4'-MDA and 2,4-TDA of PA, $4.32{\times}10^{-9}$ for acrylonitrile of ABS and $2.27{\times}10^{-7}$ for methylmethacrylate of acrylic resin. Reference Dose (RfD, mg/kg bw/day) of acrylonitrile and tolerable daily intake (TDI, mg/kg bw/day) of methacrylate were established respectively as 0.001 by EPA (US Environmental Protection Agency) and as 1.2 by WHO (World Health Organization). When comparing with RfD and TDI, the EDIs of acrylonitrile and methylmethacrylate accounted for $4.32{\times}10^{-4}%$ and $1.89{\times}10^{-5}%$ respectively.

Quantification of Odorants from Animal Husbandry using Solid-phase Microextraction (고상(固相) 미세 추출법에 의한 축산 관리시설에서 발생하는 악취성 가스 화합물의 정량적 평가)

  • Kim, Jae-Hyuck;Choi, Hong-Lim;Kown, So-Young;Lim, Hong-Lae;McConnell, Laura L.;Arispe, Susana;Park, Chul-Hwi;Kim, Hyun-Ook
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.2
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    • pp.158-164
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    • 2006
  • Offensive odor from CAFO(concentrated animal feeding operation) and its control have become a significant issue in Korea. Control of odors from the CAFO requires to identify major odorant and their generation mechanisms. In this study, an easy method to collect gas sample and to quantify its odorants is proposed. The method involves on-site odorant extraction with solid-phase microextraction and quantitation with GC/MSD or GC/FID. Analytes of the current study include: trimethylamine(TMA), carbon disulfide($CS_2$), dimethyl sulfide(DMS), dimethyl disulfide(DMDS), acetic acid(AA), propionic acid(PA) and n-butyric acid(BA). The resulting linearity($R^2$) of calibration curve for each analyte was good over the range from several ppbv to ppmv; 0.984 for TMA(0.056-1.437), 0.996 for $CS_2$(0.039-0.999), 0.994 for DMS(0.029-0.756), 0.995 for DMDS(0.024-0.623), 0.992 for AA(0.068-1.314), 0.955 for PA(0.047-0.940), and 0.976 for BA(0.036-0.712). Method detection limits were 5.67, 6.39, 5.78, 25.2, 0.098, 0.363 and 0.099 ppbv for AA, PA, BA, TMA, DMS, $CS_2$, and DMDS, respectively. With the developed method, odorants from poultry, swine, and cattle barns were analysed. All the compounds but DMDS were detected from the sample collected in the poultry barn, and their levels exceeded the representative published human olfactory threshold.

Proposal on for Response System to International Terrorism (국제 테러리즘의 대응체제 구축방안)

  • Suh, Sang-Yul
    • Korean Security Journal
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    • no.9
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    • pp.99-131
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    • 2005
  • Terrorism which became today's common phenomena over the world is one of the most serious threats the world confront. Although International society make and operate outstanding anti-terrorism system, terror would never end without solving fundamental problems. The main body of terrorism converts from nation to organization and from organization to cell, which makes it difficult for us to recognize the main body. Since the target of today's new terrorism is many and unspecified persons, terrorists will never hesitate to use mass destruction weapons such as nuclear, biological, chemical weapons, and also use cyber-technique or cyber-terrorism. So, effective counter-terrorism measures should be performed as follows. First, it must be better for international society should make long-time plan of solving fundamental problems of terrorism other than to operate directly on terror organization and its means. Second, preventive method should be made. The most effective method of eradicating terrorism is prevention. For this, it is necessary to remove environmental elements of terrorism and terrorist bases, and to stop inflow of money and mass destruction weapons to terrorists. Third, integrated anti-terror organization should be organized and operated for continuous counter-terrorism operations. Also international alliance for anti-terrorism should be maintained to share informations and measures. Fourth, concerned department in the government should prepare counter-terrorism plans in their own parts as follows and make efforts to integrate the plans. - Ministry of Government Administration and Home Affairs : conventional terror - Ministry of Health and Welfare : bio-terror - Ministry of Science and Technology : nuclear-terror Especially, they should convert their policy and operation from post-terror actions to pre-terror actions, designate terror as national disaster and organize integrated emergency response organization including civil, government, and military elements. In conclusion, pre-terror activities and remedy of fundamental causes is the best way to prevent terror. Also, strengthening of intelligence activities, international cooperations, and preventive and comprehensive counter-measures must not ignored.

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Retentive bond strength of fiber-reinforced composite posts cemented with different surface treatments (Fiber reinforced composite post의 표면 처리에 따른 접착 강도)

  • Roh, Hyunsik;Noh, Kwantae;Woo, Yi-Hyung;Pae, Ahran
    • The Journal of Korean Academy of Prosthodontics
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    • v.52 no.2
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    • pp.113-120
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    • 2014
  • This study will evaluate the effectiveness of various pretreatments when fiber-reinforced composite (FRC) post is bonded to endodontically treated tooth with resin cement. Materials and methods: Canal shaping of FRC post (DT Light post, Size 3, Bisco Inc., Schaumburg, IL, USA) was performed on endodontically treated premolars at 1.5 cm from CEJ. Samples were divided into 6 groups of surface treatment after conventional washing and drying to the canal. Total of 24 FRC posts were randomly divided into 6 groups of surface treatment as follows: Group C: control - no surface treatment, Group A: airborne-particle abrasion (Cojet sand, 3M ESPE), Group S: silanization (Bis-silane, Bisco Inc.), Group M: universal primer (Monobond-plus primer, Ivoclar Vivadent Inc.), Group AS: silanization after airborne-particle abrasion, Group AM: universal primer treatment after airborne-particle abrasion. Pretreated fiber posts were cemented with resin-based luting material and photo-polymerized and cut to the thickness of 1 mm. Push-out test using a universal testing machine was performed. Bonding failure strength of post dislodgement was measured and the type of bonding failure was classified. Data were analyzed with Kruskal-Wallis test and multiple comparison groups were performed using Tukey HSD value of rank test (${\alpha}=0.05$). Results: Group AS showed significantly highest bonding strength. Group S, group AM, group A, and group M showed lower bonding strength in order. The control group showed the lowest bonding strength. Conclusion: Surface treatment with silane showed to be the most effective of the surface pretreatment methods for cementation of FRC post. Surface treatment with universal primer showed no significant difference compared with no surface treatment group as for bonding strength.

Usefulness of Data Mining in Criminal Investigation (데이터 마이닝의 범죄수사 적용 가능성)

  • Kim, Joon-Woo;Sohn, Joong-Kweon;Lee, Sang-Han
    • Journal of forensic and investigative science
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    • v.1 no.2
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    • pp.5-19
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    • 2006
  • Data mining is an information extraction activity to discover hidden facts contained in databases. Using a combination of machine learning, statistical analysis, modeling techniques and database technology, data mining finds patterns and subtle relationships in data and infers rules that allow the prediction of future results. Typical applications include market segmentation, customer profiling, fraud detection, evaluation of retail promotions, and credit risk analysis. Law enforcement agencies deal with mass data to investigate the crime and its amount is increasing due to the development of processing the data by using computer. Now new challenge to discover knowledge in that data is confronted to us. It can be applied in criminal investigation to find offenders by analysis of complex and relational data structures and free texts using their criminal records or statement texts. This study was aimed to evaluate possibile application of data mining and its limitation in practical criminal investigation. Clustering of the criminal cases will be possible in habitual crimes such as fraud and burglary when using data mining to identify the crime pattern. Neural network modelling, one of tools in data mining, can be applied to differentiating suspect's photograph or handwriting with that of convict or criminal profiling. A case study of in practical insurance fraud showed that data mining was useful in organized crimes such as gang, terrorism and money laundering. But the products of data mining in criminal investigation should be cautious for evaluating because data mining just offer a clue instead of conclusion. The legal regulation is needed to control the abuse of law enforcement agencies and to protect personal privacy or human rights.

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The Usefulness of Diffusion-weighted MR Imaging for Differentiation between Degenerative Spines and Infectious Spondylitis (퇴행성 척추와 감염성 척추염의 감별에 있어서 확산강조영상의 유용성)

  • 박원규;변우목;최준혁
    • Investigative Magnetic Resonance Imaging
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    • v.6 no.2
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    • pp.152-157
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    • 2002
  • Purpose : The differential diagnosis between Modic type I degenerative spine and infectious spondylitis sometimes is difficult, because the affected bone marrows in both disease show similar signal intensity on conventional MR imaging. We evaluate the usefulness of diffusion-wighted MR imaging for differential diagnosis between Modic type I degenerative spine and infectious spondylitis. Materials and methods : The spin-echo and diffusion-weighted MR images of eight patients with Modic type I degenerative spines and 14 patients with infectious spondylitis diagnosed by clinical findings or CT-guided biopsies we re analyzed. The diffusion-weighted imaging sequence was based on reversed fast imaging with steady-state precession (PSIF). Signal intensity changes of the vertebral bone marrow on conventional spin-echo and diffusion-weighted MR imaging were compared between degenerative spine and infectious spondylitis. Results : On T1-weighte d images, the affeted bone marrow in both disease showed hypointense signals. On T 2-weighted images, all of type I degenerative spine and 11 of infectious spondylitis showed hyperintensity, and three of infectious spondylitis showed heterogeneo us mixed signal intensity. On diffusion-weighted MR images, all of type I degenerative spine were hypointense with peripheral high signal intensity to normal vertebral body, but infectious spondylitis was hyperintense (n = 11) and hypointense (n=3). Conclusion : Diffusion-weighted MR imaging is useful to differentiate Modic type I degenerative spine from infectious spondylitis. On diffusion-weighted images, the high singal intensity of bone marrow suggests infectious spondylitis, whereas the low signal intensity of bone marrow with peripheral focal high signal intensity suggests type I degenerative spine.

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Availability of 2mm videothoracoscope in Bullectomy of Primary Spontaneous Pneumothorax (원발성 자연 기휴의 기포절제술에서 2mm 비디오 흉강경의 유효성)

  • Lee, Yuen-Jae;Park, Chul;Kim, Jong-Seok;Kim, Han-Yong;Yoo, Byung-Ha
    • Journal of Chest Surgery
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    • v.34 no.8
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    • pp.621-625
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    • 2001
  • For many years, 10mm videothoracoscope has been widely used in bullectomy of primary spontaneous pneumothorax. However we used a 2mm videothoracoscope to minimize operative wound. Thus, we compared the clinical results of bulllectomy using 2mm videothoracoscope with bullectomy using 10mm videothoracoscope. Material and method: We analyzed 118 patients who underwent VATS for primary spontaneous pneumothorax from April, 1998 to December, 2000. 2mm videothoracoscope was used in 53 patients(Group A) and 10mm videothoracoscope was used in 65 patients(Group B). The mean age was 20.2$\pm$6.9 years old in group A and 20.1$\pm$6.1 years old in group B. The mean follow up was 10.9$\pm$3.8 months in group A and 11.4$\pm$4.3 months in group B. Result: The operation time was shorter in group A than group B(55.7$\pm$22.9 minutes, 71.2$\pm$21.4 minutes, p<0.05). The duration of postoperative hospital stay was shorter in group A than group B(7.2$\pm$3.2 days, 9.2$\pm$3.6 days, p<0.05). The duration of postoperative chest tube indwelling was shorter in group A than group B(4.7$\pm$3.1 days, 6.3$\pm$2.8 days, p<0.05). The duration of postoperative air leakage(0.6$\pm$2.1 days, 1.0$\pm$2.4 days, p>0.05), the amount of analgesics(1.38$\pm$1.0 ampules, 1.7$\pm$1.4 ampules, p>0.05), the amount of analgesics(1.38$\pm$1.0 ampules, 1.7$\pm$1.4 ampules, p>0.05), postperative complications(2 cases, 7cases, p>0.05) and recurrences(1 case, 1 case, p>0.05) were not statistically different between two groups. Operative wound was smaller in group A than B. Conclusion: There were non adverse results in group A than group B. Furthermore, bullectomy using 2mm videothoracoscope brought us minimized operative wound and good cosmetic results. Thus, we could recommend bullectomy using 2mm videothoracoscope in primary spontaneous penumothorax.

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Enhancing Science Self-efficacy and Science Intrinsic Motivation through Simulated Teaching-learning for Pre-service Teachers (탐구 기반 모의 수업 실연이 예비 교사들의 과학적 자기 효능감, 과학 내재 동기에 미치는 영향)

  • Lee, Hyundong
    • Journal of Korean Elementary Science Education
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    • v.42 no.4
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    • pp.560-576
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    • 2023
  • The purpose of this investigation is to: (1) to derive an improvement factor for inquiry-based simulated teaching-learning in pre-service teacher training programs, and pre-service teachers practice simulated teaching that reflect the improvement factor, (2) to analyze the difference in science intrinsic motivation according to science self-efficacy and inquiry-based simulated teaching-learning experience. To achieve these goals, we recruited five elementary and secondary teachers as experts to help us develop an improvement factor based on expert interviews. Subsequently, third-year pre-service teachers of a university of education participated in our analysis of differences in science intrinsic motivation, according to their level of science self-efficacy and experience with inquiry-based simulated teaching-learning. Our methodology involved applying the analytic hierarchy process to expert interviews to derive improvement factor for inquiry-based simulated teaching-learning, followed by a two-way ANOVA to identify significant differences in science intrinsic motivation between groups with varying levels of science self-efficacy. We also conducted post-analysis through MANOVA statements. The results of our study indicate that inquiry-based simulated teaching-learning can be improved through activities that foster digital literacy, ecological literacy, democratic citizenship, and scientific inquiry skills. Moreover, small group activities and student-centered teaching-learning approaches were found to be effective in developing core competencies and promoting science achievements. Specifically, pre-service teachers prepared a teaching-learning course plan and inquiry-based simulated teaching-learning in seventh-grade in the Earth and Space subject area. Pre-service teachers' science intrinsic motivation analyze significant differences in all levels of science self-efficacy before and after simulated teaching-learning and significant difference in the interaction effect between simulated teaching-learning and scientific self-efficacy. Particularly, group with low scientific self-efficacy, the difference in science intrinsic motivation according to simulated teaching-learning was most significant. Teachers' scientific self-efficacy and intrinsic motivation are needed to improve science achievement and affective domains of students in class. Therefore, this study contributes to suggest inquiry-based simulated teaching-learning reflecting school practices from the pre-service teacher curriculum.