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Combustion Characteristics of Pinus rigida Specimens Treated with Phosphorus-Nitrogen Additives (인-질소 첨가제로 처리된 리기다 소나무 시험편의 연소특성)

  • Chung, Yeong-Jin
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.13-19
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    • 2015
  • This study was performed to test the combustive properties of Pinus rigida specimens treated with phosphorus (P) and nitrogen (N) additives. Each Pinus rigida specimen was painted three times with 15 wt% P-N additive solutions at room temperature. After drying the treated specimens, the combustion properties were examined using a cone calorimeter (ISO 5660-1). The time to ignition (TTI) for the treated specimens was 90 to 148 s except for the specimen treated with PP/$4NH_4^+$, and the time to flameout (TF) was 556 to 633 s, which was longer than that of virgin plate. While the The specimens treated with P-N additives showed 12.5 to 43.4% higher mean heat release rate ($HRR_{mean}$) and 11.8 to 43.1% higher total heat release (THR) than virgin plate. The effective heat of combustion (EHC) was by 2.9 to 17.5% lower than that of virgin plate. It can thus be concluded that the combustion-retardation properties were partially improved compared to those of virgin plate.

Effect of Electrical Preactivation of Recipient Cytoplasm on Nuclear Remodelling in Nuclear Transplant Rabbit Embryos (수핵란의 전 활성화가 토끼 핵이식 수정란의 핵 재구성에 미치는 효과)

  • 전병균;김윤연;정기화;곽대오;이효종;최상용;박충생
    • Korean Journal of Animal Reproduction
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    • v.21 no.3
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    • pp.229-238
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    • 1997
  • Chromosome condensation and swelling of the donor nucleus have been known as the early morphological indicators of chromatin remodelling after injection of a foreign nucleus into an enucleated recipient cytoplasm. The effects of non-preactivation and electrical preactivation of recipient cytoplasm, prior to fusing a donor nucleus, on the profile of nuclear remodelling in the nuclear transplant rabbit embryos were evaluated. The embryos of 16-cell stage were collected and synchronized to G1 phase of 32-cell stage. The recipient cytoplasms were obtained by removing the first polar body and chromosome mass by non-disruptive microsurgical procedure. The separated G1 phase blastomeres of 32-cell stage were injected into non-preactivated recipient cytoplasms. Otherwise, the enucleated recipient cytoplasms were preactivated by electrical stimulation and the separated G1 phase blastomeres of 32-cell stage were injected. After culture until 20h post-hCG injection, the nuclear transplant oocytes were electrofused by electrical stimulation. The nuclei of nuclear transplant embryos fused into non-preactivated and/or preactivated recipient cytoplasm were stained by Hoechst 33342 at 0, 1.5, 2, 4, 6, 8, 10 hrs post-fusion and were observed under an fluorescence microscopy. Accurate measurements of nuclear diameter were revealed with an ocular micrometer at 200$\times$. Upon blastomere fusion into non-preactivated recipient cytoplasm, a prematurely chromosome condensation at 1.5 hrs post-fusion and nuclear swelling at 8 hrs post-fusion were occurred as 91.6% and 86.1%, respectively. But the nuclei of nuclear transplant embryos fused into preactivated recipient cytoplasm, as o, pp.sed to non-preactivated recipient cytoplasm, were not occurred chromosome condensation and extensive nuclear swelling. Nuclear diameter fused into non-preactivated and preactivated recipient cytoplasm at hrs post-fusion was 30.2$\pm$0.74 and 15.2$\pm$1.32${\mu}{\textrm}{m}$, respectively. These results indicated that onset of unclear condensation and swelling which was associated with oocytes activation were critical steps in the process of chromatin swelling. Futhermore, complete reprogramming seemed only possible after remodelling of the donor nucleus by chromosome condensation and nuclear swelling.

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Studies on Phenotype of Reproduction and Production of Human Growth Hormone(hGH) with Transgenic Rats II. Different Reproductive Phenotypes Determined by hGH Levels in hGH Transgenic Rats (Human 성장호르몬을 도입한 Transgenic Rats의 작출과 번식표현형에 관한 연구 II. 형질전환된 Rats의 hGH수준이 번식표현형에 미치는 영향)

  • 장규태;김성현;성환후;주학진;박미령;윤창현
    • Korean Journal of Animal Reproduction
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    • v.22 no.2
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    • pp.137-143
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    • 1998
  • The effects of continuous GH(hGH) secretion on the female reproduction was studies in adults female transgenic rats expressing the hGH gene with a mouse whey acid protein (mWAP) promotor. Two line of transgenic female rats carrying the mWAP/hGH gene were established and used in the study. One was characterized by relatively high levels of serum hGH (high line), and the other had relatively low levels (low line). 1. High line female rats had recurring, Pseudopregancy-like estrous cycles accompanied by increased serum progesterone level for 2 weeks after ovulation, and they were fertile. 2. In the rats, luteinization occurred spontaneously without cervical stimulation, probably due to high levels of serum hGH, which has prolactin (PRL)-like activity in the rat. 3. Low line female rats had recurring, regular 4-days estrous PRL surge following cervical stimulation were not, detected and PRL secretion was not induced by a dopamine antagonist. 4. The ovarian tissue in this line had a much higher number of corpora lutea and grew much heavier than in normal littermates, suggesting impairment of PRL induced structural luteolized. Su, pp.ession of PRL secretion in the low line rats was, at least in part, due to a marked decrease in the number of lactotrophs in the pituitary. The present study shows that the serum hGH level plays a crucial role in regulating luteal function in female transgenic rats expressing the hGH gene.

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Characterization of dissociation catalysts for waste plastics (폐플라스틱 분해 촉매의 특성)

  • Kim, Moon-Chan;Lee, Cheal-Gyu
    • Analytical Science and Technology
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    • v.23 no.4
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    • pp.383-388
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    • 2010
  • Catalytic dissociation reaction was studied in order to transform waste plastics to oil by using noble metal supported catalysts. XRD, SEM, and GC/MSD analysis were performed to find the crystalline structure and shape, and product distribution. Generally, dissociation reaction occurs at low temperature compared to pyrolysis. Dissociation reaction has advantage of gasoline yield with respect to pyrolysis which products mainly $C_1\simC_4$. The result of dissociation reaction, gasoline was obtained much as a product. $C_5\simC_{11}$ compounds were produced as a gasoline product on Pt-zeolite among noble metal catalysts at $340^{\circ}C$. The conversion of dissociation reaction of waste plastics on the prepared catalyst was above 70% over $340^{\circ}C$.

Numerical Simulation of Irregular Wave Transformation due to Wave-induced Current over a Submerged Elliptic Shoal (수중타원형 천퇴상 불규칙파의 파랑쇄파류에 의한 변형 수치모의)

  • Choi, Jun-Woo;Baek, Un-Il;Yoon, Sung-Bum
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.19 no.6
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    • pp.565-573
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    • 2007
  • The effect of wave and current interactions on irregular wave transformation over a submerged elliptic shoal is investigated based on numerical simulations of the Vincent and Briggs experiment [Vincent, C.L., Briggs, M.J., 1989. Refraction-diffraction of irregular waves over a mound. Journal of Waterway, Port, Coastal and Ocean Engineering, 115(2), pp. 269-284]. The numerical simulations are conducted by a combination of REF/DIF S(a wave model) and SHORECIRC(a current model) and a time dependent phase-resolving wavecurrent model, FUNWAVE. In the simulations, the breaking-induced currents defocus waves behind the shoal and bring on a wave shadow zone that shows relatively low wave height distributions. The computed results of the combined model system agree better with the measurements than the computed results obtained by neglecting wave-current interaction do. In addition, the results of FUNWAVE show a good agreement with the measurements. The agreement indicates that it is necessary to take into account the effect of breaking-induced current on wave refraction when wave-breaking occurs over a submerged shoal.

Nonthermal Sterilization of Dried Laver by Intense Pulsed Light with Batch System (회분식 광펄스 처리에 의한 마른 김의 비가열 살균)

  • Kim, Ae-Jin;Shin, Jung-Kue
    • Korean Journal of Food Science and Technology
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    • v.46 no.6
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    • pp.778-781
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    • 2014
  • Intense pulsed light (IPL) is a nonthermal technology emerging as an alternative to conventional thermal treatment. The purpose of this study was to investigate the effect of IPL treatment on the microbial inactivation, color alteration, and temperature change of dried laver to evaluate the commercial feasibility of IPL as a sterilization method. IPL treatment (10 min at 1,000 V and 5 pps) resulted in approximately 1.6 log CFU/g decrease in microbial cell viability. After IPL treatment, the surface temperature of dried laver increased by $1.9^{\circ}C$. The color lightness of dried laver increased with increased treatment time, while redness and yellowness decreased. However, these color differences were not significant.

A Streaming System based on Transcoding using the Prediction Period (예측주기를 이용한 트랜스코딩 기반의 스트리밍 시스템)

  • Kim, Sung-Min;Kim, Hyun-Hee;Park, Si-Yong;Chung, Ki-Dong
    • Journal of KIISE:Software and Applications
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    • v.33 no.10
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    • pp.823-835
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    • 2006
  • Multimedia is a very popular service in the Internet. But, we cannot provide multimedia service at a uniform content, because networks and devices are various. Thus, an adaptive service is needed for multimedia transmission. Video Transcoding is the good solution that can service multimedia adaptively. This paper proposes the streaming system that is composed of encoder, transcoder, decoder The encoder enhanced time complexity and PSNR in case of transcoding using PP(Prediction Period). The decoder is almost same as the traditional media player. Transcoder reduced time complexity through combination of prediction period in encoder and skipping period to control frame rate in transcoder. In simulation results, the performances of proposed scheme outperform the system with traditional transcoder in time complexity and PSNR.

Operating characteristics of Floating Gate Organic Memory (플로팅 게이트형 유기메모리 동작특성)

  • Lee, Boong-Joo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.8
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    • pp.5213-5218
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    • 2014
  • Organic memory devices were made using the plasma polymerization method. The memory device consisted of ppMMA(plasma polymerization MMA) thin films as the tunneling and insulating layer, and a Au thin film as the memory layer, which was deposited by thermal evaporation. The organic memory operation theory was developed according to the charging and discharging characteristics of floating gate type memory, which would be measured by the hysteresis voltage and memory voltage with the gate voltage values. The I-V characteristics of the fabricated memory device showed a hysteresis voltage of 26 [V] at 60 ~ -60 [V] double sweep measuring conditions. The programming voltage was applied to the gate electrode in accordance with the result of this theory. A programming voltage of 60[V] equated to a memory voltage of 13[V], and 80[V] equated to a memory voltage of 18[V]. The memory voltage of approximately 40 [%]increased with increasing programming voltage. The charge memory layer charging or discharging according to the theory of the memory was verified experimentally.

A Study on Devided Skirt Pattern for Women's Clothing (디바이디드 스커트원형설계에 관한 연구 -18~24세 여성을 중심으로-)

  • Cho Sung Hee;Rim Won Ja
    • Journal of the Korean Society of Clothing and Textiles
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    • v.8 no.1
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    • pp.57-67
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    • 1984
  • The purpose of this study is to develop a devided skist Pattern drafting method for Korean Women between the ages of 18$\~$24 on the basis of their physical characteristics which differs from those of other races in its size and figure. The study procednras are as follows : 1, A new devided skirt pattern drafting method is developed based on the results of draping to find the essential measuring items for devided skirt construction, 27 items of KAIST measurement data analysis to establish representative and independent items and fitting tests. 2. To establish fittness and comfort in the new pattern comparing it with in a conventional one, asensory evaluation is applied. According to the statistical analysis of the results of the sensory evaluation, the findings are as followings ; 1. Composite reliability coefficient is 0.68. 2. Qut of 30 items, 25 items for fittness show significant differences (pp$\leqq$0.05, p$\leqq$0.01, P$\leqq$0.001) between the two, with the new pattern better fitted, presenting a pleasing appearance in hormony with the figure and contributing to the wearer's sense of wellbeing. 3. Hip crotch and hem dimensions for comfort show significant differences (p$\leqq$0.05) between the two, with the new pattern more comfortable, but no significant difference is showed between the two in activity variable. 4. The new pattern drafting method is shown in figuke 4.

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Study on the Sexing of Mouse Embryos by Chromosomal Analysis (염색체 분석에 의한 생쥐초기부의 성 판별에 관한 연구)

  • 신현동;김정익
    • Korean Journal of Animal Reproduction
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    • v.10 no.1
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    • pp.27-35
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    • 1986
  • As a preliminary experiment to establish the process on the sexing of mouse embryos by chromosomal analysis, present studies were carried out with inbred (ICR, C57BL) and F1 hybrid [(ICR${\times}$C57BL) = F1 ${\times}$ ICR] mice to investigate the blastomere numbers and mitotic indices (M.I.) to the developmental stage of embryos recovered, the optimum periods of anti-mitotic agent administration, the successful rates of sexing and sex-ratio. The results obtained were summarized as follows: 1. The blastomere numbers (mean${\pm}$S.E.) of the morula and blastocyst were 18${\pm}$0.4 and 54${\pm}$0.7, respectively. 2. Whereas the M.I. of F1 hybrid (16${\pm}$0.2%) was higher than that fo inbred ICR (15${\pm}$0.1%) and C57BL (12${\pm}$0.6%) in the different strains, the morula (7${\pm}$0.6%) was higher than that of blastocyst (6${\pm}$0.4%) in the case of embryo stages. 3. Following to anti-mitotic agents treated, the M.I. of embryos cultured with Colcemid (17${\pm}$1.1%) was superior to that fo embryos cultured with Velban (12${\pm}$0.9%) and the Colcemid injection (7${\pm}$0.4%). 4. The successful rate of sexing in the blastocyst (38.7%; 124/320) was superior to the morula (35.9%; 52/145), and the F1 hybrid (48.1%) was higher than that of inbred ICR (42.4%) and C57 BL (28.2%). 5. In the successful rate of sexing to the methods of administration, the embryos cultured with Colcemid (46.0%) was superior to that of embryos cultured with Velban (39.0%) and the Colcemid injection (38.8%). 6. Of 98 embryos sexed after culture with Colcemid, 89(90.8%) were observed between 2 and 4 hrs. In the case of Velban treatment, 83.1% (74/89) was observed between 2$\frac{1}{2}$ and 4$\frac{1}{2}$ hrs. 7. Out of 761 prepared embryos it was possible to sex 311; 157 were male and 154 were female, i.e.a sex-ratio of 50% a, pp.oximately.

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