• 대한화학회지
• /
• 제32권4호
• /
• pp.342-350
• /
• 1988

$Hg^{2+}$수용액내에서 $[Co(en)_2Cl_2]^+$의 Cl이 $H_2O$로 치환되는 속도를 UV/vis 분광광도계로 측정하여$Hg^{2+}$를 고려했을때의 속도식을 결정하고, 촉매가 관여한 타당한 반응메카니즘을 제안하였다. 그리고 생성물에서 분리 할 수 없는 cis-형과 trans-형이 생성될 때 이들 이성질체의 비율계산식을 만들고 이식에 의하여 이들 이성질체의 비율을 결정하였다. 본 연구에서 $Hg^{2+}$에 대한 반응차수는 cis-$[Co(en)_2Cl_2]^+$경우 1차이고 trans-$[Co(en)_2Cl_2]^+$경우 2차이다. 그리고 cis형 보다는 trans-형의 경우 더 빠른 반응으로 나타났고 생성물은 cis-형이 약 97%이고 trans-형이 약 3%정도 생성되었다. 이러한 속도자료와 활성화파라메타로 부터 본 반응계가 Id 메카니즘으로 반응이 진행되는 타당한 반응메카니즘을 제안하였다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제15권23호
• /
• pp.10061-10066
• /
• 2015

Background: The aetiological relationship between human papillomavirus (HPV) infection and cervical cancer (CC) is widely accepted. Our goal was to determine the prevalence of HPV types in Mexican women attending at the Mexican Institute for Social Security from different areas of Mexico. Materials and Methods: DNAs from 2,956 cervical samples were subjected to HPV genotyping: 1,020 samples with normal cytology, 931 with low-grade squamous intraepithelial lesions (LGSIL), 481 with high grade HGSIL and 524 CC. Results: Overall HPV prevalence was 67.1%. A total of 40 HPV types were found; HPV16 was detected in 39.4% of the HPV-positive samples followed by HPV18 at 7.5%, HPV31 at 7.1%, HPV59 at 4.9%, and HPV58 at 3.2%. HPV16 presented the highest prevalence both in women with altered or normal cytology and HPV 18 presented a minor prevalence as reported worldwide. The prevalence ratio (PR) was calculated for the HPV types. The analysis of PR showed that HPV16 presents the highest association with CC, HPV 31, -33, -45, -52 and -58 also demonstrating a high association. Conclusions: The most prevalent HPV types in cervical cancer samples were -16, -18, -31, but it is important to note that we obtained a minor prevalence of HPV18 as reported worldwide, and that HPV58 and -52 also were genotypes with an important prevalence in CC samples. Determination of HPV genotypes is very important in order to evaluate the impact of vaccine introduction and future cervical cancer prevention strategies.

• 한국의료질향상학회지
• /
• 제17권1호
• /
• pp.79-88
• /
• 2011

Background : Evidence-based guidelines are now used for enteral nutrition(EN) in neurosurgical intensive care unit patients who mostly depend on EN. This study compared and analyzed the nutritive conditions of patients before and after they underwent guideline based nutritional interventions in order to determine whether using these guidelines improved their calorie supply. Methods : Data on the patients' nutritional requirements, maximum calorie supply through EN, serum albumin level, and total lymphocyte count were collected and analyzed using SAS version 9.1.3. All the statistical analyses were performed at a significance level of P<0.05. Result : The maximum calorie supply through EN was $923.1{\pm}359.7$ kcal before the intervention and $1254.4{\pm}196.3$ kcal after the intervention; this difference was statistically significant(P<0.05). The ratio of nutritional requirements to maximum calorie supply through EN was $55.5{\pm}22.4%$ and $74.2{\pm}13.9%$ before and after the intervention, respectively; this difference was statistically significant(P<0.05). This indicates a 19% increase in the ratio after the nutritional intervention. The serum albumin level also significantly increased from $2.7{\pm}0.6g/dL$ before the intervention to $3.2{\pm}0.4g/dL$ after the intervention(P<0.05). The total lymphocyte count slightly increased from $1267.7{\pm}728.2cells/mm^3$ before the intervention to $1801.9{\pm}1211.5cells/mm^3$ after the intervention; this difference was not statistically significant. Conclusion : The results showed that using the evidence-based feeding guidelines for interventions increased the calorie supply and improved the patients' nutritive conditions from moderate malnutrition to mild malnutrition.

• 한국토양비료학회지
• /
• 제44권3호
• /
• pp.321-330
• /
• 2011

원예용 상토 생산 시 자재의 혼합으로 결정되는 상토의 물리적 특성은 화학적 특성과는 달리 식물생육기간동안 변화가 거의 없고, 식물 생육에 직접적인 영향을 미친다. 따라서 자재의 혼합비율 설정은 매우 중요하며, 이에 대한 분석 연구는 지속적으로 이뤄져야 한다. 하지만 우리나라의 상토 분석법과 국제적으로 표준화되어 있는 분석법간의 차이로 인해 외국의 분석결과와 국내의 분석결과를 비교 해석하는데 어려움이 있다. 따라서 본 연구에서는 EN 분석법과 RDA 분석법에 따라 피트모스, 펄라이트, 버미큘라이트의 혼합비율에 따른 물리적 특성 변화를 관찰하고, 분석법 간의 차이점을 조사하였다. 연구결과, 각각의 분석법에 따른 상토의 물리적 특성에 차이가 있었으며, 이는 상토 분석 시 전처리 과정의 차이에 의한 것으로 보인다. 또한 원예용 상토 자재로 널리 사용 중인 펄라이트는 내부 공극은 많으나 겉이 막혀있는 특성 때문에 농촌진흥청 상토 분석법에 제시된 입자밀도 항목 중 기존 Pycnometer를 응용한 입자밀도의 측정으로 분석할 경우 EN 분석법과 다른 경향의 결과를 나타냈다. 식물 생육에 적합한 물리성인 공극률 85% 이상, 기상 20-30% 등과 비교 시 EN 분석법으로 분석한 결과에서 피트모스가 혼합된 상토 중 8:2:0과 6:4:0 (peatmoss:perlite: vermiculite)의 상토가 적정기준을 만족하였고, RDA 분석법으로 분석한 결과에서는 6:2:2로 혼합된 상토가 적정기준을 만족하였다. 하지만 RDA 분석법에 제시된 전처리 과정 중 건조처리의 영향으로 인해 EAW와 WBC의 기준까지 만족하는 상토는 없었으며, 분석 방법 전처리 과정에 대한 수정이 필요할 것으로 판단된다. 본 연구에서 제시한 결과를 바탕으로 상토 자재 혼합에 따른 물리적 특성 변화를 삼각도에 응용하게 되면 향후 상토 물리성 연구 및 분석 방법 간의 관계 연구에 많은 도움을 줄 것으로 생각한다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1998년도 가을 학술발표회 논문집(I)
• /
• pp.36-41
• /
• 1998

Recently, it has been reported that recycling of wasted glasses should be a hot issue in related business field. Thus, the purpose of this experimental research is to recycle wasted glasses by substituting for the cement in mortar and concrete. As a pilot test, workability and the strength of mortar with recycled glass have been tested and analyzed according to replacement ratio of recycled glass with grain size of them. As a result, considering the workability and the strength of mortar containing recycled glass, the existence of the optimum replacement ratio and grain size of them have been obtained.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2001년도 추계학술발표대회 개요집
• /
• pp.15-18
• /
• 2001

• Journal of Welding and Joining
• /
• 제35권1호
• /
• pp.74-78
• /
• 2017

In auto ancillary fabrication industry, GMAW is a very useful & important welding process and EN10025 S 235 Grade is common material used for manufacturing of two wheeler chassis. This research gives the detail influence of welding process parameters such as welding current, welding voltage, wire speed on the penetration in EN10025 S 235 Grade mild steel material. The experimentation of this research has been carried out by using three factors, three level Taguchi DOE method. To analyze & optimize the welding parameters & characteristics, analysis of variance, L9 orthogonal array & signal to noise ratio are used. Length of Penetration in addition to the depth of penetration is major concern in fillet welded joints, as the penetration decides the strength of the welded joint. After analysis of penetration in all 9 welded samples, optimize parameters readings verified & found probability value within 0.05.From this research it is come to know that welding current & welding voltage is major parameters which affects the penetration in welded joints.

• International Journal of Computer Science & Network Security
• /
• 제23권12호
• /
• pp.213-219
• /
• 2023

In recent years, popularity of deep learning (DL) is increased due to its ability to extract features from Hyperspectral images. A lack of discrimination power in the features produced by traditional machine learning algorithms has resulted in poor classification results. It's also a study topic to find out how to get excellent classification results with limited samples without getting overfitting issues in hyperspectral images (HSIs). These issues can be addressed by utilising a new learning network structure developed in this study.EfficientNet-B4-Based Convolutional network (EN-B4), which is why it is critical to maintain a constant ratio between the dimensions of network resolution, width, and depth in order to achieve a balance. The weight of the proposed model is optimized by Search and Rescue Operations (SRO), which is inspired by the explorations carried out by humans during search and rescue processes. Tests were conducted on two datasets to verify the efficacy of EN-B4, with Indian Pines (IP) and the University of Pavia (UP) dataset. Experiments show that EN-B4 outperforms other state-of-the-art approaches in terms of classification accuracy.

• Journal of Welding and Joining
• /
• 제23권1호
• /
• pp.69-76
• /
• 2005

Recently, application of arc welding to galvanized carbon steel sheet is on the increasing Ould in the fields of automobile and construction industries. In arc welding process, zinc is evaporated in weld pool, even under the appropriate welding condition and produce blowhole and/or pit. Zinc gas cause instability of arc and increase spatter and fume. This research is purposed to minimize the heat-input and the formation of porosities in the welded joint of the galvanized carbon steel sheet using variable polarity AC wave pulse MIG welding system. An appropriate welding condition which showed low spatter and good bead appearance was acquired by applying the AC pulse MIG welding machine to DC duplicated MIG welding with the solid wire. When oxygen gas was added to shield gas of MIG welding for galvanized steel sheet, arc length was increased and arc stability was improved. In the AC duplicated welding, the loss of galvanized layer was decreased as the amount of heat-input was decreased when the EN ratio was increased under the condition that average welding current was evenly set.

• 한국안전학회지
• /
• 제32권5호
• /
• pp.8-12
• /
• 2017

Bicycles are very popular sporting goods in these days. Thus, the durability of bicycles is very important for the safety of bicyclists. It is well known that a bicycle frame is a major component which is essential to the safety and performance of a complete bicycle. In this study, the durability of bicycle frames were experimentally investigated under the fatigue load. Eighty bicycle frames with different types and materials were prepared and tested according to EN standards. Three kinds of fatigue loads, that is, pedalling, vertical and horizontal fatigue load, which occur constantly during riding a bicycle, were applied to the bicycle frames. The experimental results show that the horizontal fatigue load was the severest mode to pass EN standard. The pass ratio of horizontal fatigue load test was 45.2%, while the pass ratio of vertical fatigue load test was 100%. Most of cracks were found at the right side of bottom bracket shell and at the intersection area between head tube and down tube. It seems that the experimental results can be applied to improve the safety and performance of a bicycle frame.