• Atmosphere
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• v.33 no.5
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• pp.531-548
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• 2023

We developed the Aviation Convective Index (ACI) for predicting deep convective area using the operational global Numerical Weather Prediction model of the Korea Meteorological Administration. Seasonally optimized ACI (ACI_SnOpt) was developed to consider seasonal variabilities on deep convections in Korea. Yearly optimized ACI (ACI_YrOpt) in Part 1 showed that seasonally averaged values of Area Under the ROC Curve (AUC) and True Skill Statistics (TSS) were decreased by 0.420% and 5.797%, respectively, due to the significant degradation in winter season. In Part 2, we developed new membership function (MF) and weight combination of input variables in the ACI algorithm, which were optimized in each season. Finally, the seasonally optimized ACI (ACI_SnOpt) showed better performance skills with the significant improvements in AUC and TSS by 0.983% and 25.641% respectively, compared with those from the ACI_YrOpt. To confirm the improvements in new algorithm, we also conducted two case studies in winter and spring with observed Convectively-Induced Turbulence (CIT) events from the aircraft data. In these cases, the ACI_SnOpt predicted a better spatial distribution and intensity of deep convection. Enhancements in the forecast fields from the ACI_YrOpt to ACI_SnOpt in the selected cases explained well the changes in overall performance skills of the probability of detection for both "yes" and "no" occurrences of deep convection during 1-yr period of the data. These results imply that the ACI forecast should be optimized seasonally to take into account the variabilities in the background conditions for deep convections in Korea.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.151-152
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• 2020

Recently, concrete expansion anchors which are a type of post-installed mechanical anchors are widely used in reinforcement concrete structures. In order to be used in the reinforced concrete structures designed in accordance with ACI 318-19 or ACI 349-13, the structural performance tests of the concrete expansion anchors should be conducted in accordance with ACI 355.2. The effectiveness factor(k) of concrete expansion anchors should be determined through the reference tests and used for the design of anchorage to concrete according to ACI 318-19 or ACI 349-13. In this study, we will look into the method for determining the effectiveness factor(k) of concrete expansion anchors and anchorage design process of concrete expansion anchors by using the effectiveness factor(k) in accordance with ACI 349-19.

• Proceedings of the Korean Nuclear Society Conference
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• 1999.10a
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• pp.373.1-373
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• 1999

• Journal of the Korea Concrete Institute
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• v.21 no.3
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• pp.377-386
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• 2009

A reference diffusion coefficient model from ACI life-365 is drawn from test results by NT build 443. This test method gives a time-averaged diffusion coefficient during immersion period, thus the ACI model uses the time-averaged diffusion coefficient as a reference value. ACI model needs to be revised, considering the difference between the time-average value and reference value at specified time. In this study, firstly the analytic solutions of diffusion equation are derived considering the initiation time and period of exposure to chloride, and secondly the time-averaged diffusion coefficient from NT build 443 is converted into the diffusion coefficient at reference time. From this study, the reference diffusion coefficient of ACI model should be modified to be about 10% larger values than those of present ACI model. For convenient design of service life, previous relationship between the chloride diffusion coefficient from NT build 443 and that from NT build 492 is also modified. To compare the chloride diffusion coefficients of ACI and JCI models, the reference chloride diffusion coefficient with respect to the JCI model is drawn in the similar form of ACI model's, and service life prediction by ACI life-365 method is confirmed to give a conservative result.

• Structural Engineering and Mechanics
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• v.32 no.6
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• pp.705-724
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• 2009

The two major widely used building design code documents of reinforced concrete structures are the ACI 318-05 and Eurocode for the Design of Concrete Structures EC2. Therefore, a thorough comparative analysis of the provisions of these codes is required to confirm their validity and identify discrepancies in either code. In this context, provisions of flexural computations would be particularly attractive for detailed comparison. The provisions of safety concepts, design assumptions, cross-sectional moment capacity, ductility, minimum and maximum reinforcement ratios, and load safety factors of both the ACI 318-05 and EC2 is conducted with parametric analysis. In order to conduct the comparison successfully, the parameters and procedures of EC2 were reformatted and defined in terms of those of ACI 318-05. This paper concluded that although the adopted rationale and methodology of computing the design strength is significantly different between the two codes, the overall EC2 flexural provisions are slightly more conservative with a little of practical difference than those of ACI 318-05. In addition, for the limit of maximum reinforcement ratio, EC2 assures higher sectional ductility than ACI 318-05. Overall, EC2 provisions provide a higher safety factor than those of ACI 318-05 for low values of Live/Dead load ratios. As the ratio increases the difference between the two codes decreases and becomes almost negligible for ratios higher than 4.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.32-32
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• 2001

본 연구는 돼지 난포란의 체외성숙시 Adenylate cyclase(ACi) 첨가가 돼지 수정란의 배발달에 미치는 효과를 검토하기 위하여 수행하였다. 돼지 난포란은 0.1% PVA, 3.05 mM D-Glucose, 0.91 mM sodium pyruvate, 0.57 mM cysteine, 0.5 $\mu\textrm{g}$/$m\ell$ LH, 0.5 $\mu\textrm{g}$/$m\ell$ FSH 그리고 10 ng/$m\ell$ EGF가 첨가된 TCM-199 배양액에서 ACi를 농도별로 첨가하여 42~44 시간 배양함으로써 체외성숙을 유도하였다. 그리고 ACi가 배발달율에 미치는 효과를 알아보기 위하여 체외수정 medium에 0, 0.1, 1% 첨가한 다음, 체외수정을 유도하고 체외배양을 실시하였다 체외성숙시 22시간 동안 ACi를 0, 0.1, 1, 및 10 $\mu\textrm{g}$/$m\ell$로 처리한 결과 33.3, 31.5, 34.1, 및 36.0%로 대조구와 처리구간의 통계학적인 유의한 차이는 나타나지 않았다. 그러나 체외성숙시 ACi을 0, 0.01, 0.1, 1.0 $\mu\textrm{g}$/$m\ell$로 처리한 결과, 25.5%, 33.3, 26.7, 및 25.6%의 배발달율이 확인되어 유의한 ACi의 처리효과가 확인되었다. 이러한 처리효과는 ACi를 0.01%로 첨한 처리구(배발달율, 33.3%)에서 가장 높게 나타났다. 그리고 체외수정시 caffeine과 ACi를 첨가한 실험에서, 1 mM caffeine과 ACi를 0, 1, 10, 20 $\mu\textrm{g}$/$m\ell$로 첨가한 결과, 대조구(30.4%)에 비해 처리구(40.9, 37.9, 및 43.5%)에서 높은 배발달율을 나타냈다. 0.5 mM caffeine과 ACi를 0, 1, 10, 20 $\mu\textrm{g}$/$m\ell$ 로 첨가시는 대조구(37.8%)와 처리구(36.5, 36.0, 및 36.0%)간의 유의한 차이는 나타나지 않았다. 또한 ACi가 배발달율에 미치는 효과를 알아보기 위하여 체외수정 배양액에 0, 0.1, 1% 첨가한 결과는 Table 1에서 보는 바와 같이, 처리구(30.3와 37.0%)가 대조구(22.6%)보다 통계학적으로 유의하게 높은 배발달율을 나타냈다. 따라서 본 연구의 결과는 체외성숙 또는 체외수정용 배양액 내에 ACi을 첨가함으로써 초기배의 발달을 효과적으로 유도할 수 있을 것이며, 앞으로 이러한 기술을 활용한다면 좀더 효율적으로 형질전환 동물이나 복제동물을 생산하게 될 것으로 사료된다.

• Food Science and Preservation
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• v.24 no.2
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• pp.303-311
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• 2017

This study was performed to evaluate the quality characteristics and the antioxidant activities of yanggeng added with the aged black chestnut inner shells (ACI). The levels of ACI addition to Yanggeng were 0%, 1%, 3%, or 5%. The moisture content and the reducing sugar contents of Yanggeng increased with the amount of ACI. The pH of Yanggeng with ACI decreased with the amount of ACI, but the acidity increased. Depending on the amount of ACI added, the lightness (L) and yellowness (b) values of Yanggeng with ACI decreased in the Hunter color system, and the redness (a) value increased. Textural properties by TPA showed that hardness, springiness and chewiness decreased as increase in the amount of ACI added. Total phenol content in the Yanggeng added with ACI increased with the amount of ACI added. Increasing amount of ACI addition enhanced antioxidant activities of Yanggeng, as evidenced by DPPH radical scavenging activity and hydroxyl radical scavenging activity assays. In the preference test, Yanggeng added with 3% ACI showed the highest overall preference and texture. Based on these results, when 3% ACI was added to Yanggeng the quality characteristics, antioxidant property and sensory properties were excellent.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.909-914
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• 2001

It is important to consider an effect of concrete member sizes when estimating the ACI rectangular stress block of a reinforced concrete flexural member. However, the experimental data and analytical analyses are still not available for a proper evaluation. For all types of loading conditions, the trend is that the size of an ACI rectangular stress block tends to change when the member sizes change. In this paper, the size variations of strength coefficients for ACI rectangular stress block and actual stress distribution have been studied. Results of a series of C-shaped specimens subjected to axial compressive load and bending moment were adopted from references 1 and 2. The analysis results show that the effect of specimen sizes on strength coefficients for ACI rectangular stress block and actual stress distribution of concrete member was apparent. Thus, the results suggest that the current strength criteria based design practice should be reviewed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2406-2413
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• 2014

Since clear span-to-depth ratio is used to define what is so called a deep beam, it is an important parameter ratio for study about deep beam. Deep beams can be designed by flexure design method, and shear provided by concrete ($v_c$) and by steel ($v_s$) for deep flexure members are provided in ACI 318-99 [1]. But in later version of ACI (from ACI 318-02) it is not provided and deep beams shall be designed either by taking into account nonlinear distribution of strain or by Appendix A of Strut-and-Tie Models (STM). The trend of deep beam design seems to be familiar with strut-and-tie model, but ACI traditional design is not forgotten. By comparing these two method, there should a point which definitely explain the different between the two methods. In this study, 68 samples result of steel, after reinforcement arrangement, are taken to be analyzed.

• Journal of Chest Surgery
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• v.32 no.11
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• pp.984-988
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• 1999

Background: Donor-specific blood transfusion(DSBT) before organ transplantation has been demonstrated to prolong allograft survival; the mechanism of this effect has remained unclear. Only a few researches have been performed on this subject in our country. Material and Method: To investigate the effect of DSBT, we selected 5 donor recipient combinations using rats of pure strain such as PVG, ACI, and LEW. One ml of donor whole blood was transfused to each recipient through the femoral vein 7 days prior to transplantation. The donor heart was transplanted to the recipient's abdominal vessels heterotopically using modified Ono and Lindsey's microsurgical technique. Five transplantations were done for each combination. Postoperatively, donor heart beat was palpated everyday through the recipent's abdominal wall. Rejection was defined as complete cessation of donor heart beat. Result: The allogeneic heart grafts transplanted from PVG strain to ACI strain(PVG ACI) without DSBT were acutely rejected(mean survival 10.2 days). With pretransplant DSBT, the cardiac allografts in PVG ACI and LEW PVG combinations survived indefinitely(more than 100 days), those in ACI PVG combination survived 12 to 66 days(mean 31.8 days), those in PVG LEW survived 8 to 11 days(mean 10.0 days), and those in ACI LEW survived 7 to 9 days(mean 8.0 days). In brief, DSBT prior to heart transplantation was definitely effective in PVG ACI and LEW PVG combinations and moderately effective in ACI PVG combination, but not effective in PVG LEW and ACI LEW combinations. Conclusion: DSBT prior to heart transplantation showed variable effects, but might prolong cardiac allograft survival indefinitely in some donor recipient strain combinations. The mechanism of this effect should be further investigated.