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Effect of ${\alpha}-Amylase$ Treatment of Brown Rice(Goami) Alcohol Fermentation By-Product (현미(고아미) 알코올발효 부산물의 ${\alpha}-amylase$처리 효과)

  • Woo, Seung-Mi;Kim, Tae-Young;Yeo, Soo-Hwan;Kim, Sang-Burm;Kim, Mi-Hyun;Woo, Sang-Chel;Jeong, Yong-Jin
    • Food Science and Preservation
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    • v.14 no.6
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    • pp.617-623
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    • 2007
  • To utilize the non-heat treated alcoholic by-products of brown rice(Goami) as food sources, the quality characteristics change according to the treatment conditions of ${\alpha}-amylase$ were evaluated. It resulted that the increase of hydrolysis temperature correspondingly increased the soluble solids, total dietary fiber and total sugar in the by-products of Goami, and the highest reducing sugar content was observed at $80^{\circ}C$. The free amino acids contents were tended to slowly decrease by the hydrolysis temperature more than $70^{\circ}C$, and the highest content of oligosaccharides were detected at the hydrolysis temperature of $80^{\circ}C$. The soluble solid according to the ${\alpha}-amylase$ concentration resulted to increase with the increase of the enzyme concentration and the total dietary fiber revealed similarly showing approximately 0.65%. The high content of reducing sugars was observed at the enzyme concentration around 0.08%(v/w). Total sugars and oligosaccharides contents tend to increase as the concentration of enzyme increased, and the content of oligosaccharides acquired at the enzyme concentration more than 0.10%(v/w) maintained to show rather similar contents. The soluble solids and total dietary fiber by hydrolysis time were found to show 6.66% and 0.65%, respectively at more than 60 min of hydrolysis, and the reducing sugars and total sugars were found to be 3,600 and 4,800 mg% in all treatment groups showing no significant difference. The content of oligosaccharides was increased with the increase of hydrolysis time, and the content was similar at more than 90 min of hydrolysis by ranging around 2,100 mg%. Based upon these results, the by-products of Goami are expected to be used as various food sources showing the highest dietary fiber and oligosaccharides contents by the hydrolysis at $80^{\circ}C$ for 90 min with the addition of 0.10%(v/w) of ${\alpha}-amylase$.

Effect of moisture content on terminal velocities of domestic wheat and foreign materials (함수율에 따른 우리밀과 이물의 종말속도에 미치는 영향)

  • Choi, Eun-Jung;Kim, Hoon;Kim, Sang-Suk;Kim, Oui-Woung
    • Food Science and Preservation
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    • v.23 no.5
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    • pp.746-752
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    • 2016
  • This research was carried out to identify aerodynamic property as a function of moisture content for designing equipment such as for post-harvest management. Terminal velocity of two wheat varieties {Backjjung (B) and Jogyeong (J)} with selected sound, damaged kernel and foreign materials (Wheat stick, Wheat husks) were measured with a designed vertical wind column at different moisture contents from about 9 to 30% wet basis. The results showed that terminal velocity of wheat and foreign materials except of Jogyeong's husks (p<0.05) had a significant difference at p<0.001. With increasing moisture content, the aerodynamic property values of the kernels and foreign materials of the two wheat varieties increased linearly. In detail, terminal velocity of sound and damaged kernel increased from 5.46 to 7.13 m/sec (B) and 7.48 to 8.60 m/sec (J), damaged kernel from 5.91 to 7.00 m/sec (B) and 6.48 to 7.75 m/sec (J). For foreign materials the terminal velocity of wheat stick increased from 2.92 to 4.07 m/sec (B) and 3.74 to 5.22 m/sec (J) whereas that of husks from 1.07 to 1.85 m/sec (B) and 2.02 to 2.33 m/sec (J) each. For air separation of wheat and foreign materials, the air flow should be less than 5.22 m/sec due to the range (1.07~5.22 m/sec) of foreign materials in wheat.

Quality characteristics and antioxidative activity of fermented milk added with hot water extract of Cordyceps militaris grown upon Tenebrio molitor (갈색거저리 유래 밀리타리스 동충하초 열수 추출물을 첨가한 발효유의 품질 특성과 항산화 활성)

  • Gim, Do-Woo;Koo, Hui-Yeon;Kim, Seon-Gon;Park, Jun-Ki;Kim, Yu-Jin;Huh, Chang-Ki;Kim, Yong-Doo;Kim, Hyun-Jin
    • Food Science and Preservation
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    • v.24 no.8
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    • pp.1067-1078
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    • 2017
  • This study was carried out to investigate the physicochemical and antioxidant properties of fermented milk with addition of hot water extract of Cordyceps militaris grown upon Tenebrio molitor. The general components of Cordyceps militaris grown upon Tenebrio molitor are moisture 10.85%, crude protein 18.44%, crude fat 2.07%, crude ash 5.46%. The DPPH radical scavenging activities of different solvents were the highest (74.81 EDA%) with hot water extract sample. The acidity of fermented milk was high with increasing amount of extracts. The pH of fermented milk reached 4.60-4.66 after 4 h of fermentation, and the number of lactic acid bacteria was highest (11.70 log CFU/mL) with 1% fermented milk. The moisture content of fermented milk showed no significant difference. In addition, contents of crude protein were not significantly different according to addition amount. Regarding Hunter's color values, L value decreased as the amount of extract increased, whereas a value and b value increased. The content of free amino acid increased with increasing amount of extract. The DPPH free radical scavenging ability and ABTS free radical scavenging ability of fermented milk were significantly different as the addition amount of extract increased. In the sensory evaluation, fermented milk containing 1% of extract showed the highest preference.

Theoretical Analysis of Bragg-Reflector Type FBAR with Resonance Mode (공진 모드에 따른 Bragg-Reflector Type FBAR 의 이론적 분석)

  • 조문기;윤영섭
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.40 no.11
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    • pp.9-18
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    • 2003
  • Two configurations of Film Bulk Acoustic Wave Resonators with acoustic quater-wave bragg reflector layers are theoretically analyzed using equivalent circuits and the difference of their characteristics are discussed. We compare the characteristics of λ/2 mode to those of ideal FBAR with top and bottom electrode contacting air and the characteristics of λ/4 mode to those of ideal FBAR with top electrode contacting air and bottom electrode clamped. We assume that the piezoelectric film is ZnO, the electrode is A1 and the substrate is Si, ABCD parameters are extracted and input impedance is calculated by converting the equivalent circuit from Mason equivalent circuits to the simplified equivalent circuits that ABCD parameters are extracted possible, From the variation of resonance frequency due to the change of thickness of reflector layers and the variation of electrical Q due to the change of mechanical Q of reflector layers, it is confirmed that the reflector layer just under the bottom electrode have the greatest effect on the varation of resonance frequency and electrical Q. It is shown that the number of reflector layers required for the saturation of electrical Q decreases with the increase of the impedance ratio of reflector layers and electrical Q of λ/2 mode is larger than that of λ/4 mode, Electromechanical coupling factor is independent of the number of layers, The impedance ratio of reflector layers becomes larger as the electromechanical coupling factor becomes larger, The electromechanical coupling factor of the two mode are smaller than those of ideal FBARs because of the trapping of acoustic energy in the reflector layers, The insertion loss of the ladder filter decreases with the increase of the number of reflector layers but the bandwidth is not affected much by the number of reflector layers, As the impedance ratio of reflector layers becomes larger the insertion loss becomes smaller and the bandwidth becomes wider, In our analysis of the two mode, characteristics of λ/2 mode appear to be slightly more favorable than that of λ/4 mode

First Principles Calculations on Magnetism of CrPt3(001) Thin Films (CrPt3(001) 박막의 자성: 제일원리계산)

  • Jeong, Tae Sung;Jekal, Soyoung;Rhim, S.H.;Hong, S.C.
    • Journal of the Korean Magnetics Society
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    • v.27 no.2
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    • pp.41-48
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    • 2017
  • Recent study shows that ordered alloy of $L1_2$ $XPt_3$ (M = V, Cr, Mn, Co, and Fe) exhibits various magnetic phases such as ferromagnetic-to-antiferromagnetic transition at the $MnPt_3$ surface. Moreover, it has been argued that $CrPt_3$, in particular, possess large magnetocrystalline anisotropy and Kerr rotation with possible violation of Hund's rule. As such, we extend our work to thickness dependence of the magnetic structure of $CrPt_3$ thin film using density functional theory. Magnetic ground state of the bulk $CrPt_3$ turns out to be ferromagnetic (FM), where other magnetic phases such as A-type (A-AF), C-type (C-AF), and G-type antiferromagnetic (G-AF) state have higher total energies than FM by 0.517, 0.591, and 0.183 eV, respectively, and magnetic moments of Cr in bulk are respectively 2.807 (FM), 2.805 (A-AF), 2.794 (C-AF) and $2.869_{{\mu}_B}$ (G-AF). We extend our study to $CrPt_3$(001) thin films with CrPt-and Pt-termination. The thickness and surface-termination dependences of magnetism are investigated for 3-9 monolayers (ML), where different magnetic phases from bulk emerge: C-AF for CrPt-terminated 3 ML and G-AF for Pt-terminated 5 ML have energy difference relative to FM by 8 and 54 meV, respectively. Furthermore, thickness- and surface-termination-dependent magnetocrystalline anisotropies of the $CrPt_3$(001) films are discussed.

COH-IVF Outcomes for Infertile Patients With Borderline Ovarian Tumor After Conservative Treatment (경계성 난소 종양의 보존적 수술 후 불임 환자에서 체외수정시술의 유용성)

  • Lee, Hyun-Joo;Ahn, Ka-Yougng;Hahn, Ho-Suap;Park, Chan-Woo;Yang, Kwang-Moon;Lee, In-Ho;Kim, Tae-Jin;Lim, Kyung-Taek;Lee, Ki-Heon;Kang, Inn-Soo
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.2
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    • pp.87-94
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    • 2007
  • Objective: To examine determinants of successful pregnancy and evaluate COH-IVF outcomes of infertile patients after conservative surgical treatment of borderline ovarian tumor (BOT). Methods: In women of BOT (n=93), from January 1995 to December 1999, 44 of 93 women underwent conservative surgical treatment. From theses 44 women, patients characteristics, surgical and histological parameters were compared between 14 women who conceived and 30 women who failed to conceive. For 5 infertile women of 30 women who failed to conceive, 10 attempt IVF cycles were analysed; clinical pregnancy rate (CPR), implantation rate (IR) and live birth rate (LBR). Results: Women who conceived tend to be younger (25.9 vs 27.0 years) and lower serum CA-125 level (59.7 vs 72.9) compared to women who failed to conceive without significant difference. For 8 cycles out of 10 attempt IVF cycles, except for 2 cancellation cycles, the mean number of oocytes retrieved was 5.6 (range 2$\sim$16) with a mean fertilization rate of 74.4%. The CPR, IR and LBR per embryo transfer were 50.0% (4/8 cycles), 31.6% (6/19) and 50.0% (4/8 cycles) respectively. During the mean follow-up period after COH-IVF initiation, 29.6 (range 14$\sim$61) months, no recurrence was found. Conclusion: No determinant of successful pregnancy was found after conservative treatment for BOT. COH-IVF may be considered for infertile patients after conservative treatment of BOT. However, larger clinical studies with longer follow-up are necessary to evaluate the safety and efficacy of COH-IVF. All patients should be informed of the potential risks associated with ovarian hyperstimulation and close follow-up is necessary after COH-IVF.

An Experiment and Analysis for Standardize Measurement on CCFL (냉음극 형광램프의 표준화 계측을 위한 실험과 분석)

  • Jin, Dong-Jun;Jeong, Jong-Mun;Jeong, Hee-Suk;Kim, Jin-Shon;Lee, Min-Kyu;Kim, Jung-Hyun;Koo, Je-Huan;Gwon, Gi-Cheong;Kang, June-Gill;Choi, Eun-Ha;Cho, Guang-Sup
    • Journal of the Korean Vacuum Society
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    • v.17 no.4
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    • pp.331-340
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    • 2008
  • A method of measuring the current and voltage is suggested in the circuit of cold cathode fluorescent lamps (CCFLs) which are driven at a high frequency of $50{\sim}100\;kHz$ and a high voltage of several kV. It is difficult to measure the current and voltage in the lamp circuit, because the impedance of the probe at high voltage side causes the leakage current and the variation of luminance. According to the analysis of equivalence circuit with the probe impedance and leakage current, the proper measuring method is to adjust the input DC voltage and to keep the specific luminance when the probe is installed at a high voltage circuit. The lamp current is detected with a current probe or a high frequency current meter at the ground side and the voltage is measured with a high voltage probe at the high voltage side of lamp. The lamp voltage($V_C$) is measured between the ballast capacitor and the lamp electrode, and the output voltage($V_I$) of inverter is measured between inverter output and ballast capacitor. As the phases of lamp voltage($V_C$) and current ($I_G$) are nearly the same values, the real power of lamp is the product of the lamp voltage($V_C$) by the lamp current($I_G$). The measured value of the phase difference between inverter output voltage($V_I$) and lamp current($I_G$) is appreciably deviated from the calculated value at $cos{\theta}=V_C/V_I$.

Bivariate Rainfall Frequency Analysis and Rainfall-runoff Analysis for Independent Rainfall Events (독립 호우사상에 대한 이변량 강우빈도해석 및 강우-유출해석)

  • Park, Cheol-Soon;Yoo, Chul-Sang;Jun, Chang-Hyun
    • Journal of Korea Water Resources Association
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    • v.45 no.7
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    • pp.713-727
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    • 2012
  • In this study, the bivariate frequency analysis of the independent annual rainfall event series was done to be used for the runoff analysis, whose results were also compared with those from the conventional univariate frequency analysis. This study was applied to three differently-sized basins such as the Joongryang Stream, Chunggye Stream, and Ooyi Stream. The Clark model was used as the runoff model, and the SCS method was applied for the calculation of the effective rainfall. The alternating block method and the Huff method were considered to be compared for the temporal distribution of rainfall event. Summarizing the results are as follows. (1) The difference between the univariate and bivariate frequency analysis results were large when the rainfall duration was short, but significantly decreased as the rainfall duration increased. The univariate frequency analysis results were bigger when the rainfall duration was short, but smaller in opposite case. (2) The peak flow derived by applying the alternating block method was bigger than that by the Huff method. Also, the peak flow when applying the alternating block method increased as the rainfall duration increased, but converged smoothly around the rainfall duration of 24 hours. (3) For the Joongryang Stream, when applying the Huff method, the peak flow derived for the bivariate frequency analysis was bigger than that for the univariate case, but for the other two basins, the results were opposite. When applying the alternating block method, the results were consistent for all three basins that the peak flow derived by applying the bivariate frequency analysis was bigger than those by the univariate frequency analysis.

Effect of Sex Education on Middle School Students' Access to the Obscene Online Computer and Video Film Contents (성교육이 중학생의 컴퓨터와 비디오 음란물 접촉에 미치는 효과)

  • Woo, Hae-Ja;Kim, Chung-Nam;Park, Kyung-Min
    • Research in Community and Public Health Nursing
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    • v.12 no.3
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    • pp.795-814
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    • 2001
  • To evaluate the effect of sex education on middle school students' access to the obscene online computer and video film contents. 154 students were selected as experimental group. and 154 students were selected as control group, sampled randomly from Andong. Kyungbook, Korea. An analysis was performed. A non-equivalent control group pre test-post test research design was used. The data were collected from April 2nd to April 19th. 2001. A pre-survey was done on general characteristics and the condition of accessing obscene online computer and video film contents on both experimental and control group. From the survey results information. sex education contents were put together. The researcher organized 3 ready-made sex education program and explained to the four school health nurses about the ready-made sex education program step by step and they educated their selected students with three classes of 45 minutes lecture. Two weeks after the last lecture, a post-test was conducted. Four weeks from the last lecture, another post-test was conducted. The existing studies by Choi Yongseon(1998) and Kim Hyeok(1998) were reviewed and two professors in the department of community health nursing advised on the study questionnaire writing. An SPSS Win 10.0 was used. The data of respondents' general characteristics were analyzed using frequency and percentage. $X^2$ test was used to verify the homogeneity of the experimental group and the control group. Repeated Measures ANOVA was used to find out whether sex education had an effect on the awareness of obscene online computer and video film contents and under-age prostitution through the online computer networks. and time and frequency of access to the obscene online computer and video film contents. The results of the study are as follow. 1. The results of the verification of homogeneity between the experimental group and the control group showed that there was no significant difference between the experimental group and the control group. 2. The first hypothesis, 'the experimental group which received sex education would have a higher level of awareness of accessing obscene contents than the control group which did not receive the education' was supported at p<0.0001. 3. The second hypothesis. 'the experimental group which received sex education would have a higher level of awareness of underage prostitution on computer networks than the control group which did not receive the education' was supported at p<0.05. 4. The third hypothesis, 'the experimental group which received sex education would spend time less accessing obscene video and computer contents than the control group which did not receive the education' was rejected at p>.05. 5. The 4-1 hypothesis. 'the experimental group which received sex education would access obscene computer contents less frequently than the control group which did not receive the education' was supported at p<0.0001. 6. The 4-2 hypothesis, 'the experimental group which received sex education would access obscene video contents less frequently than the control group which did not receive the education' was supported at p<0.0001. In conclusion, a systematic step-by-step sex education program should be developed to protect middle school students from the harmful online computer and video film access. An effective teaching material for sex education should be prepared to decrease middle school students' access to obscene online computer and video film contents.

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Ingredients and cytotoxicity of MTA and 3 kinds of Portland cements (MTA와 포틀랜드 시멘트의 구성성분분석과 세포독성에 관한 연구)

  • Chang, Seok-Woo;Yoo, Hyun-Mi;Park, Dong-Sung;Oh, Tae-Seok;Bae, Kwang-Shik
    • Restorative Dentistry and Endodontics
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    • v.33 no.4
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    • pp.369-376
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    • 2008
  • The aim of this study was to compare the compositions and cytotoxicity of white ProRoot MTA (white mineral trioxide aggregate) and 3 kinds of Portland cements. The elements, simple oxides and phase compositions of white MTA (WMTA), gray Portland cement (GPC), white Portland cement (WPC) and fast setting cement (FSC) were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES), X-ray fluorescence spectrometry (XRF) and X-ray diffractometry (XRD). Agar diffusion test was carried out to evaluate the cytotoxicity of WMTA and 3 kinds of Portland cements. The results showed that WMTA and WPC contained far less magnesium (Mg), iron (Fe), manganese (Mn), and zinc (Zn) than GPC and FSC. FSC contained far more aluminum oxide ($Al_2O_3$) than WMTA, GPC, and WPC. WMTA, GPC, WPC and FSC were composed of main phases. such as tricalcicium silicate ($3CaO{\cdot}SiO_2$), dicalcium silicate ($2CaO{\cdot}SiO_2$), tricalcium aluminate ($3CaO{\cdot}Al_2O_3$), and tetracalcium aluminoferrite ($4CaO{\cdot}Al_2O_3{\cdot}Fe_2O_3$). The significance of the differences in cellular response between WMTA, GPC, WPC and FSC was statistically analyzed by Kruskal-Wallis Exact test with Bonferroni' s correction. The result showed no statistically significant difference (p > 0.05). WMTA, GPC, WPC and FSC showed similar compositions. However there were notable differences in the content of minor elements. such as aluminum (Al), magnesium, iron, manganese, and zinc. These differences might influence the physical properties of cements.