• Journal of electromagnetic engineering and science
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• 제4권2호
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• pp.63-67
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• 2004

DAM(Delay-And-Multiplier) intercept receiver usually detects the symbol rate of the transmitted DS spread spectrum signal for the feature extraction. It is important for secure communication to reduce the normalized output signal-to-noise ratio that is generated at the DAM intercept receiver as a measure of detectability. In this paper, several kinds of chip waveforms are novelly analyzed for LPI(Low-Probability of Intercept) communication against DAM intercept receiver. Consequently, it is shown that the rectangular chip waveform shows the best LPI performance in the bandwidth of 2/$T_c$TEX>, 4/$T_c$TEX>, and 6/$T_c$TEX>/. Except the rectangular waveform, kaiser chip waveform show better LPI performance than the other waveforms in the bandwidth of 4/$T_c$TEX> and 6/$T_c$TEX>.

• 대한화학회지
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• 제10권4호
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• pp.149-152
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• 1966

鹽素置換 anisol과 chloral hydrate를 縮合하면 D.D.T 類의 合成에서와 같이 bis compound의 化合物이 生成될 것이고 D.D.T 系統의 化合物처럼 殺蟲能이 있으리라고 豫測되므로 4-chloro anisol 과 chloral hydrate를 縮合하여 生成物의 構造를 檢討하였던 바 2,2 bis(2-methoxy-5-chlorophenyl) 1.1.1-trichloroethane임을 確認하였으며 反應條件과 「국화꼬마수염진딧물」 및 「귤응애」에 대한 殺충能을 檢討한 結果 前報文$^{(67)}$에서 發表한 바 있는 化合物들의 殺蟲能에 比하여 5培나 强한 殺蟲能을 가졌다는 事實을 알았다.

• Nutrition Research and Practice
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• 제1권4호
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• pp.363-370
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• 2007

Single nucleotide polymorphism (SNP) in adiponectin gene has been associated with insulin resistance, diabetes, and cardiovascular disease (CVD). This study was performed to investigate the association of SNP 276G${\rightarrow}$T at adiponectin gene with CVD risk factors in Korean type 2 diabetes mellitus (DM) patients. The subjects were 351 type 2 DM patients visited a DM clinic in Seoul, and the patients with known CVD were excluded. The adiponectin SNP 276G${\rightarrow}$T was analyzed and dietary intakes were assessed by a Food Frequency Questionnaire. The prevalence of G/G, G/T, and T/T genotype was 47.6%, 43.3%, and 9.1%, respectively. Male subjects with T/T genotype showed significantly lower level of adiponectin and HDL-cholesterol and significantly higher C-reactive protein (CRP) level compared to G/G and G/T genotypes. In G/G genotype, protein intake was negatively correlated to body weight, BMI, and waist circumference, and there were positive correlation between carbohydrate intake and BMI, waist-hip ratio, and ApoB/apoA-1 ratio in G/T genotype. However, in T/T genotype, there was no significant association between macronutrient intakes and anthropometric and hematological values. In conclusion, CVD risk would be high in type 2 DM patients with T/T genotype, and the association of macronutrient intakes with anthropometric and hematologic factors was different among the three adiponectin genotypes. These results may imply the need for different dietary management regime according to adiponectin genotype to lower CVD complications in Korean type 2 DM patients.

• 상하수도학회지
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• 제18권1호
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• pp.37-48
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• 2004

The purpose of this study was to evaluate adaptability of external carbon source using GPS-X program in pilot plant composed with 2-stage denitrification process. The result from analysis of pilot plant operation and GPS-X simulation showed that effluent concentration could be simulated similarly by modifying operation conditions, such as DO concentration, C/N ratio and other calibrated parameter. In order to satisfy the standard of the effluent water quality on T-N of 20mg/L, it required approximately 3.1 of C/N ratio and 50% of nitrogen removal efficiency when influent T-N is 36.9mg/L. To maintain the stable water quality of the receiving water, the effluent T-N concentration should be less than 10-15mg/L and the appropriate C/N ratio to remove nitrogen was 4.27-6.82. The analysis of sensitivity to kinetic coefficient and reaction constant showed that $Y_H$ and ${\mu}_{mAUT}$ were most sensitive to nitrate and ammonia nitrogen, relatively and sensitivity coefficient of their were 1.32, 1.98. It was concluded that as $Y_H$ decreased and ${\mu}_{mAUT}$ increased, the reaction rates of denitrification and nitrification increased and the removal efficiencies of $NO_3{^-}-N$ and $NH_4{^+}-N$ improved.

• 한국염색가공학회지
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• 제3권1호
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• pp.8-16
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• 1991

In order to investigate the fine structure of PET films, PET films were stretchd at various draw ratios (2, 3, 4, 5) below $T_g$ ($72^{\circ}C$) and then annealed at various temperatures (125, 150, 175, $200^{\circ}C$) under free-annealed (FA) and taut-annealed (TA) conditions. Such changes as thermal shrinkage, crystallinity, crystallite size, dynamic viscoelasticity and thermal behaviour were measured in relation to the draw ratio and annealing condition.The following results were obtained. 1. Thermal shirinkage increased with increasing annealing temperature and draw ratio, but decreased in case of draw ratio 4 (draw ratio 3 at $200^{\circ}C$) and above it. 2. The degree of crystallinity of FA samples were higher than those of TA samples. 3. Tan 5 of TA samples were less than those of FA samples, and storage moduli (E') and loss moduli (E") of FA samples were less than those of TA samples; moreover, maximum tan '||'&'||' temperature of FA samples were shifted toward higher temperature than those of TA samples. 4. The melting endotherm ($T_m$) and heat of fusion $(\DeltaH)$ of the PET film increased with the draw ratio and annealing temperature; in addition, premelting endotherm ($T_m$) and heat of fusion $(\DeltaH)$ of the local crystallization in the FA samples were larger than those of TA samples. 5. The X-ray diffraction pattern displayed sharp peaks gradually with the draw ratio and annealing temperature. 6. Crystallite sizes of FA samples were larger than those of TA samples.

• 환경영향평가
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• 제21권5호
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• pp.745-755
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• 2012

The relations between tributaries and mainstream were identified with the water qualities measurements in the field. Parameters of water qualities were BOD, T-N, T-P and measurements were performed by 4 events of rainfalls for 2011. The precipitation data influenced on pollutants loads. Pollutants loads were fluctuations with the seasonal variation. Gajoacheon contributed in 18.39% of BOD, 23.79% of T-N, 15.23% of T-P and Nabulcheon contributed in 13.54% of BOD, 13.05% of T-N and 13.66% of T-P in the region from Nam River_C to Nam River_D. In case of the region from Nam River_C to Nam River_D, Yongacheon river inflowed to main stream as 23.65% of BOD, 20.74% of T-N, and 15.05% of T-P.

• Journal of Biosystems Engineering
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• 제15권2호
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• pp.143-150
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• 1990

This study was conducted to estimate the ratio of Repair & Maintenance (R&M) costs to purchasing price that is one of the important factors for calculating the management costs of farm machinery. For this purpose, hour of use and R & M costs of power tiller and its attachments utilized results that were investigated with 400 sample units, 50 units by years of use from 1 to 8 years in 1988. The results obtained are summarized as follows; 1. The ratio of R & M costs per hours and annual R & M costs, accumulated R & M costs when sercice life of power tiller is 7 years were 0.017%, 5.50% and 38.52%, respectively. And in case of rotary, these ratio when its service life is 6 years were 0.072%, 7.16% and 43.0%, respectively. 2. The relationship between accumulated hours of use(t) and accumulated R & M costs(Y) of power tiller and its attachments were $Y=19.3t^{1.3}$ in power tiller, $Y=0.03t^{2.09}$ in plow, $Y=48.84t^{1.25}$ in rotary and $Y=7.45t^{1.15}$ in trailer. 3. The ratio of accumulated R & M costs to purchasing price when service life of power tiller is 7 years was 38.5%, and in case of rotary, this ratio when its service life is 6 years was 43.0%.

• 한국균학회지
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• 제38권2호
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• pp.136-141
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• 2010

본 시험은 버섯 병재배 농가에서 사용하고 있는 배지재료와 혼합배지의 수분함량, pH, 전탄소(T-C), 전질소(T-N), C/N율, 인산, 13종의 양이온 함량 등 이화학적 특성을 파악하여 기초자료로 활용하고자 수행하였다. 전국의 병재배 농가에서 임의로 선정한 35농가 중 팽나무버섯 13개소, 큰느타리버섯 14개소, 느타리버섯 8개소에서 배지재료 143점과 혼합배지 35점의 시료가 수집되었다. 배지재료의 성분함량은 동일한 명칭의 재료라도 2~5배로 차이가 많은 경우도 있었다. 그리고 농가에서 수집한 버섯재배용 혼합배지의 C/N율은 팽나무버섯과 큰 느타리버섯 배지가 $28{\pm}4$, 느타리버섯 병재배용 배지는 $21{\pm}2$의 범위이었으며 중금속 등 특정성분에 특이사항은 없었다. 그리고 배지재료별 성분함량표를 이용하여 버섯 재배용 혼합배지의 성분조성을 산출하기 위한 계산식을 제시하였다.

• Radiation Oncology Journal
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• 제14권3호
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• pp.229-236
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• 1996

목적 : 방사선 치료시 주기적으로 시행하는 말초 혈액 검사에서 백혈구 성분 중 림프구 수의 감소가 관찰되어, 저자는 방사선 치료 전, 후의 백혈구 성분 및 림프구 아형 분석을 시도하여 방사선 치료가 각 성분에 미치는 영향의 정도를 알아보고자 하였다. 대상 및 방법 : 1994년 12월부터 1995년 5월까지 동아대학교병원 치료방사선과에 내원한 환자 중 16명(폐암, 담관암, 식도암 : 2예, 뇌송과체 종양, 위암, 직장암, 악성 흑색종, 안상 배세포종, 방광암, 전립선 육종, 성상세포종, 다형성교모세포종, 다발성 골전이 폐암 : 1예)을 대상으로 하였다. 방사선 치료는 2700 cGy에서 6660 cGy까지 시행하여 정중앙 총 방사선량이 5400 cGy였다. 백혈구 및 감별계산에서 방사선 치료 전과 후의 백혈구 및 림프구, 단핵구, 과립구의 절대값과 백분을을 구하였고 림프구 아형의 분석은 유세포분석기를 이용하여 총 T 세포, 총 8 세포, 조력유발 T 세포, 억제유발 T 세포, 자연살해세포 등의 절대값과 백분유을 구하였다. 방사선 치료 전후의 절대값파 백분율을 비교하였으며 조력유발T세포에 대한 억제유발 T 세포의 비(Helper/Suppressor T cell ratio)의 변화도 분석하였다. 나아가 방사선량에 따른 각 구성비의 변화 정도를 분석하여 총 방사선량과의 상관 관계를 유추하고자하였다. 결과 : 각 환자에서 방사선 치료 전후에 측정한 값의 비교에서, 백혈구와 그 구성 성분인 림프구, 단핵구및 과립구의 수는 단핵구를 제외하고는 방사선 치료 전에 비하여 감소하였으며 특히 림프구 수의 감소는 통계적으로 유의한 차이를 보였다(p<0.05). 림프구 아형인 총 T 세포, 총 B세포, 조력유발 T 세포, 억제유발 T 세포, 자연살해세포 모두 치료전에 비해 감소하였으며(p$\geq$0.05), 조력유발 T 세포에 대한 억제유발 T 세포의 비(Helper/Suppressor T cell ratio)는 방사선 치료 전 1.52에서 치료후 1.11로 감소하였고(p<0.05) 방사선량에 따른 조력유발 T 세포에 대한 억제유발 T 세포의 비의 방사선 치료 전후에 50 Gy 미만군(5명)과 50 Gy 이상군(11명)에서 각각 0.75와 0.71이었다. 결론 : 방사선 치료 후 림프구 수와 조력유발 T 세포에 대한 억제유발 T 세포의 비는 감소하였고 억제유발 T 세포의 백분율은 증가하였다. 이상의 결과로 림프구 아형 중 조력유발 T 세포가 억제유발 T 세포보다 방사선에 보다 민감한 것으로 사료된다. 본 실험에서 방사선량에 따른 림프구 성분의 변화 분석은 대상군 수가 적고 일회 분할 방사선량이나 치료 부위의 넓이, 환자의 체표 면적의 차이에 따른 제한적 요소가 있었으며 향후 보다 많은 대상군에 대한 심도 깊은 분석이 요구된다.

• 한국환경보건학회지
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• 제37권1호
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• pp.64-72
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• 2011

This study was performed to assess the removal efficiency on nitrogen, phosphorus and organic carbon in wastewater by spatial separation and internal recycling in a modified oxidation ditch process (modified OD). The performances of the modified OD were evaluated via laboratory-scale experiments. The process was operated at hydraulic retention times of 6-48 hours and solid retention times of 17-38 days. We found that organic carbon removal efficiency increased after the modified OD operation period. T-N removal efficiency remained stable; average T-N concentration of effluent was 8.02 mg/l after modified OD operation. In contrast, T-P concentration of effluent was over 1 mg/l. Nitrogen and phosphorus removal efficiency of modified OD at HRT 12 hr were 83.1% and 74.1%, respectively. Also, maximum efficiency was found at SRTs from 20 to 30 days. T-N removal efficiency was 83.1% at a C/N ratio from 3.0 to 3.5. However, T-N removal efficiency decreased at C/N ratios over 3.5. Also, T-P removal efficiency increased with HRT at C/P ratios in the same condition. Maximum efficiency was 74.1% at a C/P ratio from 25 to 28. T-N removal efficiency was 79.2% and T-P removal efficiency was 65.3% after M4 mode operation (added to the internal recycle line connected to the anoxic reactor). The modified OD with spatial separation and internal recycling developed in this study is, therefore, believed to be an improvement for solving problems in the nutrient removal technologies.