• Title/Summary/Keyword: 활용법

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Effect of Terephthalaldehyde to Facilitate Electron Transfer in Heme-mimic Catalyst and Its Use in Membraneless Hydrogen Peroxide Fuel Cell (테레프탈알데하이드의 전자전달 강화효과에 따른 헴 단백질 모방 촉매의 성능 향상 및 이를 이용한 비분리막형 과산화수소 연료전지)

  • Jeon, Sieun;An, Heeyeon;Chung, Yongjin
    • Korean Chemical Engineering Research
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    • v.60 no.4
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    • pp.588-593
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    • 2022
  • Terephthalaldehyde (TPA) is introduced as a cross liker to enhance electron transfer of hemin-based cathodic catalyst consisting of polyethyleneimine (PEI), carbon nanotube (CNT) for hydrogen peroxide reduction reaction (HPRR). In the cyclic voltammetry (CV) test with 10 mM H2O2 in phosphate buffer solution (pH 7.4), the current density for HPRR of the suggested catalyst (CNT/PEI/hemin/PEI/TPA) shows 0.2813 mA cm-2 (at 0.2 V vs. Ag/AgCl), which is 2.43 and 1.87 times of non-cross-linked (CNT/PEI/hemin/PEI) and conventional cross liker (glutaraldehyde, GA) used catalyst (CNT/PEI/hemin/PEI/GA), respectively. In the case of onset potential for HPRR, that of CNT/PEI/hemin/PEI/TPA is observed at 0.544 V, while those of CNT/PEI/hemin/PEI and CNT/PEI/hemin/PEI/GA are 0.511 and 0.471 V, respectively. These results indicate that TPA plays a role in facilitating electron transfer between the electrodes and substrates due to the π-conjugated cross-linking bonds, whereas conventional GA cross-linker increases the overpotential by interrupting electron and mass transfer. Electrochemical impedance spectroscopy (EIS) results also display the same tendency. The charge transfer resistance (Rct) of CNT/PEI/hemin/PEI/TPA decreases about 6.2% from that of CNT/PEI/hemin/PEI, while CNT/PEI/hemin/PEI/GA shows the highest Rct. The polarization curve using each catalyst also supports the superiority of TPA cross liker. The maximum power density of CNT/PEI/hemin/PEI/TPA (36.34±1.41 μWcm-2) is significantly higher than those of CNT/PEI/hemin/PEI (27.87±0.95 μWcm-2) and CNT/PEI/hemin/PEI/GA (25.57±1.32 μWcm-2), demonstrating again that the cathode using TPA has the best performance in HPRR.

The Legal Interest of Doctor's Duty to Inform and the Compensation to Damages for Non-pecuniary Loss (의료행위에서 설명의무의 보호법익과 설명의무 위반에 따른 위자료 배상)

  • Yi, Jaekyeong
    • The Korean Society of Law and Medicine
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    • v.21 no.2
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    • pp.37-73
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    • 2020
  • Medical practice with medical adaptability is not illegal. Consent to medical practice is also not intended to exclude causes of Illegality. The patient's consent to medical practice is the exercise of the right to self-determination, and the patient's right to self-determination is take shape through the doctor's information. If a doctor violates his duty to inform, failure to inform or lack of inform constitutes an act of illegality of omission in itself. As a result, the legal interest of self-determination is violated. The patient has the right to know and make decisions on his or her own, even when it is not connected to the benefit of life and body as the subject of the body. If that infringed and lost, the non-property damage shall be recognized and the immaterial damage must be compensated. On the other hand, the violation of the duty of information does not belong to deny the compensation for physical damage. Which the legal interest violated by violation of the obligation to inform is the self-determination, and loss of opportunity of choice is recognized as ordinary damage. However, if the opportunity of choice was lost because of the infringement of the right to self-determination and the patient could not choice the better way, that dose not occur plainly bad results, under the prove of these causal relationship, that bad results could be compensated. But the unexpectable damage could not be compensated, because the physical damage is considered as the special damage due to the violation of the right of the self-determination.

Improvement in Calculating Engineer Standard Wage Rate and Its Appropriate Level Computation (엔지니어링 노임단가 산출기준 개선방안과 적정 노임단가 추정)

  • Lee, Jae Yul;Lee, Hae Kyung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.42 no.6
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    • pp.853-860
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    • 2022
  • The purpose of this study is to suggest an improvement plan for the calculation method of the engineer standard wage rate (ESWR) and to compute a reasonable ESWR. To this end, an adequacy review of theESWR calculation criteria was conducted along with an extensive engineering industry survey. The survey results were analyzed using an effective response sample of 748 companies out of 1,000 survey samples extracted by stratifying the 5,879 survey population. The main results were as follows. ①When calculating the engineering service fee, the prime contractor's engineer wage is suitable for the ESWR. The ESWR can be estimated by the formula 'average wage÷[1-proportion of subcontract orders×(1-subcontract rate)].' ② The field survey showed that the number of monthly working days was 20.35-20.54 days at 99 % confidence interval, which was significantly different from the current standard (22 days). In addition, as a result of a legal review of the ESWR criteria, it was found that the number of working days should be calculated in accordance with the Labor Standards Act after 2022. ③ Applying government guidelines, the time difference between the wage survey and the ESWR application can be corrected by the past ESWR increase rate for a specific period. ④ Using modeling based on the analysis above, the current ESWR was 13.5-14.5 % lower than the appropriate level. A lower ESWR was driven by the non-reflection of subcontract structure (4.1 %), overestimation of monthly work days (6.8-7.8 %), and application of past wage (2.6 %). The proposed model is expected to be widely used in policy making, as it can provide a useful framework for calculating the standard wage rate in similar industries as well as calculating appropriate engineering fees.

Estimation of Stem Taper Equations and Stem Volume Table for Phyllostachys pubescens Mazel in South Korea (맹종죽의 수간곡선식 및 수간재적표 추정)

  • Eun-Ji, Bae;Yeong-Mo, Son;Jin-Taek, Kang
    • Journal of Korean Society of Forest Science
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    • v.111 no.4
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    • pp.622-629
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    • 2022
  • The study aim was to derive a stem taper equation for Phyllostachys pubescens, a type of bamboo in South Korea, and to develop a stem volume table. To derive the stem taper equation, three stem taper models (Max & Burkhart, Kozak, and Lee) were used. Since bamboo stalks are hollow because of its woody characteristics, the outer and inner diameters of the tree were calculated, and connecting them enabled estimating the tree curves. The results of the three equations for estimating the outer and inner diameters led to selection of the Kozak model for determining the optimal stem taper because it had the highest fitness index and lowest error and bias. We used the Kozak model to estimate the diameter of Phyllostachys pubescens by stem height, which proved optimal, and drew the stem curve. After checking the residual degree in the stem taper equation, all residuals were distributed around "0", which proved the suitability of the equation. To calculate the stem volume of Phyllostachys pubescens, a rotating cube was created by rotating the stem curve with the outer diameter at 360°, and the volume was calculated by applying Smalian's method. The volume of Phyllostachys pubescens was calculated by deducting the inner diameter calculated volume from the outer diameter calculated volume. The volume of Phyllostachys pubescens was only 20~30% of the volume of Larix kaempferi, which is a general species. However, considering the current trees/ha of Phyllostachys pubescens and the amount of bamboo shoots generated every year, the individual tree volume was predicted to be small, but the volume/ha was not very different or perhaps more. The significance of this study is the stem taper equation and stem volume table for Phyllostachys pubescens developed for the first time in South Korea. The results are expected to be used as basic data for bamboo trading that is in increasing public and industrial demand and carbon absorption estimation.

Estimation of grid-type precipitation quantile using satellite based re-analysis precipitation data in Korean peninsula (위성 기반 재분석 강수 자료를 이용한 한반도 격자형 확률강수량 산정)

  • Lee, Jinwook;Jun, Changhyun;Kim, Hyeon-joon;Byun, Jongyun;Baik, Jongjin
    • Journal of Korea Water Resources Association
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    • v.55 no.6
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    • pp.447-459
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    • 2022
  • This study estimated the grid-type precipitation quantile for the Korean Peninsula using PERSIANN-CCS-CDR (Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Cloud Classification System-Climate Data Record), a satellite based re-analysis precipitation data. The period considered is a total of 38 years from 1983 to 2020. The spatial resolution of the data is 0.04° and the temporal resolution is 3 hours. For the probability distribution, the Gumbel distribution which is generally used for frequency analysis was used, and the probability weighted moment method was applied to estimate parameters. The duration ranged from 3 hours to 144 hours, and the return period from 2 years to 500 years was considered. The results were compared and reviewed with the estimated precipitation quantile using precipitation data from the Automated Synoptic Observing System (ASOS) weather station. As a result, the parameter estimates of the Gumbel distribution from the PERSIANN-CCS-CDR showed a similar pattern to the results of the ASOS as the duration increased, and the estimates of precipitation quantiles showed a rather large difference when the duration was short. However, when the duration was 18 h or longer, the difference decreased to less than about 20%. In addition, the difference between results of the South and North Korea was examined, it was confirmed that the location parameters among parameters of the Gumbel distribution was markedly different. As the duration increased, the precipitation quantile in North Korea was relatively smaller than those in South Korea, and it was 84% of that of South Korea for a duration of 3 h, and 70-75% of that of South Korea for a duration of 144 h.

Minimizing Estimation Errors of a Wind Velocity Forecasting Technique That Functions as an Early Warning System in the Agricultural Sector (농업기상재해 조기경보시스템의 풍속 예측 기법 개선 연구)

  • Kim, Soo-ock;Park, Joo-Hyeon;Hwang, Kyu-Hong
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.24 no.2
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    • pp.63-77
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    • 2022
  • Our aim was to reduce estimation errors of a wind velocity model used as an early warning system for weather risk management in the agricultural sector. The Rural Development Administration (RDA) agricultural weather observation network's wind velocity data and its corresponding estimated data from January to December 2020 were used to calculate linear regression equations (Y = aX + b). In each linear regression, the wind estimation error at 87 points and eight time slots per day (00:00, 03:00, 06:00, 09.00, 12.00, 15.00, 18.00, and 21:00) is the dependent variable (Y), while the estimated wind velocity is the independent variable (X). When the correlation coefficient exceeded 0.5, the regression equation was used as the wind velocity correction equation. In contrast, when the correlation coefficient was less than 0.5, the mean error (ME) at the corresponding points and time slots was substituted as the correction value instead of the regression equation. To enable the use of wind velocity model at a national scale, a distribution map with a grid resolution of 250 m was created. This objective was achieved b y performing a spatial interpolation with an inverse distance weighted (IDW) technique using the regression coefficients (a and b), the correlation coefficient (R), and the ME values for the 87 points and eight time slots. Interpolated grid values for 13 weather observation points in rural areas were then extracted. The wind velocity estimation errors for 13 points from January to December 2019 were corrected and compared with the system's values. After correction, the mean ME of the wind velocities reduced from 0.68 m/s to 0.45 m/s, while the mean RMSE reduced from 1.30 m/s to 1.05 m/s. In conclusion, the system's wind velocities were overestimated across all time slots; however, after the correction model was applied, the overestimation reduced in all time slots, except for 15:00. The ME and RMSE improved b y 33% and 19.2%, respectively. In our system, the warning for wind damage risk to crops is driven by the daily maximum wind speed derived from the daily mean wind speed obtained eight times per day. This approach is expected to reduce false alarms within the context of strong wind risk, by reducing the overestimation of wind velocities.

A Study on Home Economics Education Lesson Plan Design Using Gamification: Focusing on 'Eco-friendly Clothing Life Cycle' Theme (게이미피케이션을 활용한 가정과 수업 설계에 관한 연구: '환경친화적 의류 라이프 사이클' 주제를 중심으로)

  • Jang, Eun Ju;Kim, Hye Rin;Lee, Su Kyung;Kim, Eun Jo;Hwang, Shin Hye;Kim, Ji Seul;Kim, Nam Eun
    • Journal of Korean Home Economics Education Association
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    • v.34 no.1
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    • pp.35-57
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    • 2022
  • This study developed an 'Eco-friendly Clothing Life Cycle' class applying gamification. And the effect of and learners' satisfaction on the class were examined after implementation. The developed class was applied to 40 sophomore students from "A" high school in Gyeonggi-do from February 3, 2022, to February 10, 2022, in a total of 4 sessions. The class was conducted in the stages of production-distribution-consumption-disposal, and was conducted in a way that a mission is solved after learning in Gather Town. It is designed so that learners continuously repeat learning until they accomplish the mission. The learners completed pre-class and post-class questionnaires. And a focus group interview was conducted with a randomly selected group of three learners. According to the pre-/post-class test comparison, the gamification class on the theme of "Eco-friendly Clothing Life Cycle" was found not to have a significant effect on learners' immersion or self-directed learning attitudes. However, in the case of the learners with high levels of non-immersion tendency, the level of immersion in the class increased, and the satisfaction level was positively associated with the level of immersion and self-directed attitude. Learners expressed 'concern' and 'expectation' about the gamification class, and said that although the developed class was using a 'new teaching method', 'appropriate use' was necessary. And learners were evaluated this class as a 'student-centered class' and acknowledged that it allowed 'self-directed learning'. The teacher who implemented the class said that this class was more effective in attracting students' expectations and interests compared to the conventional classes, and that the class in the meta-verse environment was perceived as a new type of class in the non-face-to-face era. The teacher also mentioned that when applied to the actual educational field, a detailed design is needed that allows the learners to proceed smoothly, and the role of the teacher in the class was more important. And the teacher also mentioned that the class should be properly designed so that the expectations given by the 'game' do not obscure the essence of the class.

Forward Osmotic Pressure-Free (△𝜋≤0) Reverse Osmosis and Osmotic Pressure Approximation of Concentrated NaCl Solutions (정삼투-무삼투압차(△𝜋≤0) 법 역삼투 해수 담수화 및 고농도 NaCl 용액의 삼투압 근사식)

  • Chang, Ho Nam;Choi, Kyung-Rok;Jung, Kwonsu;Park, Gwon Woo;Kim, Yeu-Chun;Suh, Charles;Kim, Nakjong;Kim, Do Hyun;Kim, Beom Su;Kim, Han Min;Chang, Yoon-Seok;Kim, Nam Uk;Kim, In Ho;Kim, Kunwoo;Lee, Habit;Qiang, Fei
    • Membrane Journal
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    • v.32 no.4
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    • pp.235-252
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    • 2022
  • Forward osmotic pressure-free reverse osmosis (Δ𝜋=0 RO) was invented in 2013. The first patent (US 9,950,297 B2) was registered on April 18, 2018. The "Osmotic Pressure of Concentrated Solutions" in JACS (1908) by G.N. Lewis of MIT was used for the estimation. The Chang's RO system differs from conventional RO (C-RO) in that two-chamber system of osmotic pressure equalizer and a low-pressure RO system while C-RO is based on a single chamber. Chang claimed that all aqueous solutions, including salt water, regardless of its osmotic pressure can be separated into water and salt. The second patent (US 10.953.367B2, March 23, 2021) showed that a low-pressure reverse osmosis is possible for 3.0% input at Δ𝜋 of 10 to 12 bar. Singularity ZERO reverse osmosis from his third patent (Korea patent 10-22322755, US-PCT/KR202003595) for a 3.0% NaCl input, 50% more water recovery, use of 1/3 RO membrane area, and 1/5th of theoretical energy. These numbers come from Chang's laboratory experiments and theoretical analysis. Relative residence time (RRT) of feed and OE chambers makes Δ𝜋 to zero or negative by recycling enriched feed flow. The construction cost by S-ZERO was estimated to be around 50~60% of the current RO system.

A Generalized Adaptive Deep Latent Factor Recommendation Model (일반화 적응 심층 잠재요인 추천모형)

  • Kim, Jeongha;Lee, Jipyeong;Jang, Seonghyun;Cho, Yoonho
    • Journal of Intelligence and Information Systems
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    • v.29 no.1
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    • pp.249-263
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    • 2023
  • Collaborative Filtering, a representative recommendation system methodology, consists of two approaches: neighbor methods and latent factor models. Among these, the latent factor model using matrix factorization decomposes the user-item interaction matrix into two lower-dimensional rectangular matrices, predicting the item's rating through the product of these matrices. Due to the factor vectors inferred from rating patterns capturing user and item characteristics, this method is superior in scalability, accuracy, and flexibility compared to neighbor-based methods. However, it has a fundamental drawback: the need to reflect the diversity of preferences of different individuals for items with no ratings. This limitation leads to repetitive and inaccurate recommendations. The Adaptive Deep Latent Factor Model (ADLFM) was developed to address this issue. This model adaptively learns the preferences for each item by using the item description, which provides a detailed summary and explanation of the item. ADLFM takes in item description as input, calculates latent vectors of the user and item, and presents a method that can reflect personal diversity using an attention score. However, due to the requirement of a dataset that includes item descriptions, the domain that can apply ADLFM is limited, resulting in generalization limitations. This study proposes a Generalized Adaptive Deep Latent Factor Recommendation Model, G-ADLFRM, to improve the limitations of ADLFM. Firstly, we use item ID, commonly used in recommendation systems, as input instead of the item description. Additionally, we apply improved deep learning model structures such as Self-Attention, Multi-head Attention, and Multi-Conv1D. We conducted experiments on various datasets with input and model structure changes. The results showed that when only the input was changed, MAE increased slightly compared to ADLFM due to accompanying information loss, resulting in decreased recommendation performance. However, the average learning speed per epoch significantly improved as the amount of information to be processed decreased. When both the input and the model structure were changed, the best-performing Multi-Conv1d structure showed similar performance to ADLFM, sufficiently counteracting the information loss caused by the input change. We conclude that G-ADLFRM is a new, lightweight, and generalizable model that maintains the performance of the existing ADLFM while enabling fast learning and inference.

Association between dietary protein intake and overweight and obesity among Korean children and adolescents: data from the 2014-2019 Korea National Health and Nutrition Examination Survey (한국 아동 및 청소년의 단백질 섭취와 과체중 및 비만과의 연관성: 2014-2019년 국민건강영양조사 자료를 활용하여)

  • Sumin Kim;Kyungho Ha
    • Journal of Nutrition and Health
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    • v.56 no.1
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    • pp.54-69
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    • 2023
  • Purpose: Proteins are major components of the body and essential nutrients for proper growth and development. However, studies on protein intake in children and adolescents are insufficient. A few previous studies have reported the relationship with growth indicators, but results vary depending on the source of protein. Therefore, the current study investigates the relationship between protein intake and overweight and obesity among children and adolescents in Korea. Methods: Based on the 2014-2019 Korea National Health and Nutrition Examination Survey, 5,567 children and adolescents aged 6-18 years, who participated in a 24-hour dietary recall with information on height and weight, were included in this study. Protein intake was estimated as percentage of total energy (% of energy) and was classified into animal and plant protein according to the food source. Overweight and obesity were defined using the 2017 pediatric and adolescent growth chart. Results: Total protein intake of the subjects was estimated as 14.5% of total energy (animal protein 8.3% and plant protein 6.3%). The group with the highest total protein intake had a higher odds ratio (OR) of overweight/obesity than those with the least protein intake (OR, 1.36, 95% confidence interval (CI), 1.10-1.67, p for trend = 0.003). When classified by food source, the group with the highest animal protein intake had a significantly higher OR of overweight/obesity than subjects with the lowest intake (OR, 1.30, 95% CI, 1.05-1.61, p for trend = 0.016). However, plant protein was not significantly associated with overweight/obesity. Conclusions: These findings suggest that a high intake of animal protein in children and adolescents increases the risk of being overweight and obese. In order to develop normal growth and prevent obesity in the future, it is necessary to determine an appropriate protein intake level through nutrition education programs and prospective studies on balanced protein intake.