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Life Cycle Assessment (LCA) of the Wind Turbine : A case study of Korea Yeongdeok Wind Farm (한국 영덕 풍력단지 사례 연구를 통한 풍력 발전의 환경 영향 평가)

  • Jun Heon Lee;Jun Hyung Ryu
    • Korean Chemical Engineering Research
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    • v.61 no.1
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    • pp.142-154
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    • 2023
  • As the importance of the environment has been recognized worldwide, the need to calculate and reduce carbon emissions has been drawing an increasing attention throughout various industrial sections. Thereby the discipline of LCA (Life Cycle Assessment) involving raw material preparation, production processes, transportation and installation has been established. There is a clear research gap between the need and the practice for Korean Case of renewable energy industry, particularly wind power. To bridge the gap, this study conducted LCA research on wind power generation in the Korean area of Yeongdeok, an example of a domestic onshor wind power complex using SimaPro, which is the most widely used LCA system. As a result of the study, the energy recovery period (EPT) of one wind turbine is about 10 months, and the GHG emitted to generate power of 1 kwh is 15 g CO2/kWh, which is competitive compared to other energy sources. In the environmental impact assessment by component, the results showed that the tower of wind turbines had the greatest impact on various environmental impact sectors. The experience gained in this study can be further used in strengthening the introduction of renewable energy and reducing the carbon emission in line with reducing climate change.

Recanalization Rate and Clinical Outcomes of Intravenous Tissue Plasminogen Activator Administration for Large Vessel Occlusion Stroke Patients

  • Min-Hyung Lee;Sang-Hyuk Im;Kwang Wook Jo;Do-Sung Yoo
    • Journal of Korean Neurosurgical Society
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    • v.66 no.2
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    • pp.144-154
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    • 2023
  • Objective : Stroke caused from large vessel occlusion (LVO) has emerged as the most common stroke subtype worldwide. Intravenous tissue plasminogen activator administration (IV-tPA) and additional intraarterial thrombectomy (IA-Tx) is regarded as standard treatment. In this study, the authors try to find the early recanalization rate of IV-tPA in LVO stroke patients. Methods : Total 300 patients undertook IA-Tx with confirmed anterior circulation LVO, were analyzed retrospectively. Brain computed tomography angiography (CTA) was the initial imaging study and acute stroke magnetic resonance angiography (MRA) followed after finished IV-tPA. Early recanalization rate was evaluated by acute stroke MRA within 2 hours after the IV-tPA. In 167 patients undertook IV-tPA only and 133 non-recanalized patients by IV-tPA, additional IA-Tx tried (IV-tPA + IA-Tx group). And 131 patients, non-recanalized by IV-tPA (IV-tPA group) additional IA-Tx recommend and tried according to the patient condition and compliance. Results : Early recanalization rate of LVO after IV-tPA was 12.0% (36/300). In recanalized patients, favorable outcome (modified Rankin Scale, 0-2) was 69.4% (25/36) while it was 32.1% (42/131, p<0.001) in non-recanalized patients. Among 133 patients, non-recanalized after intravenous recombinant tissue plasminogen activator and undertook additional IA-Tx, the clinical outcome was better than not undertaken additional IA-Tx (favorable outcome was 42.9% vs. 32.1%, p=0.046). Analysis according to the perfusion/diffusion (P/D)-mismatching or not, in patient with IV-tPA with IA-Tx (133 patients), favorable outcome was higher in P/D-mismatching patient (52/104; 50.0%) than P/D-matching patients (5/29; 17.2%; p=0.001). Which treatment tired, P/D-mismatching was favored in clinical outcome (iv-tPA only, p=0.008 and IV-tPA with IA-Tx, p=0.001). Conclusion : The P/D-mismatching influences on the recanalization and clinical outcomes of IV-tPA and IA-Tx. The authors would like to propose that we had better prepare IA-Tx when LVO is diagnosed on initial diagnostic imaging. Furthermore, if the patient shows P/D-mismatching on MRA after IV-tPA, additional IA-Tx improves treatment results and lessen the futile recanalization.

A Study on the Effectiveness of the Book Delivery and Reading Program for Vulnerable Children: Focusing on the Case of Library A in Gyeonggi-do (취약계층 어린이를 위한 책 배달, 책 읽어주기 프로그램의 효과에 관한 연구 - 경기도 A시 도서관 사례를 중심으로 -)

  • Jeong Ja Kong;Miah Cho;Boomi Lee
    • Journal of Korean Library and Information Science Society
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    • v.54 no.2
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    • pp.131-154
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    • 2023
  • This study analyzed the effectiveness of visiting reading programs for vulnerable children, focusing on the case of libraries in A-si, Gyeonggi-do. Library A utilized a visiting teacher to deliver books that matched the children's levels and interests through non-face-to-face interactions, or to engage in face-to-face reading sessions and deliver books together. In 2022, a total of 158 individuals from 103 families participated in the program, with 103 individuals from 67 families delivering books and 55 individuals from 36 families engaging in book reading activities. Pre- and post-project surveys were conducted to assess the reading effects, and interviews were conducted with the visiting teachers. The analysis revealed that the level and interest of the children during book delivery and reading sessions were identified, and the effects of reading books with high levels of interaction were significant. Infants who were able to easily acquire reading experiences according to their age exhibited better reading effects compared to elementary school students. The program aimed at the new participant group showed slightly greater effectiveness than the group of continuing participants. Furthermore, following the implementation of the program, improvements were observed in reading interest, reading attitude, reading environment, reading interaction, self-esteem, social skills, language ability, reading proficiency, self-directed learning ability, and library utilization rate.

Developing an Attitude Scale for Korean Style Flavors (한국적인 맛 관련 소비자 식태도 성향 분류 척도 개발)

  • Kim, Jin-Young;Cha, Sung-Mi;Chung, La-Na;Kim, Kwang-Ok;Chung, Seo-Jin
    • Journal of the Korean Society of Food Culture
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    • v.24 no.6
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    • pp.805-812
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    • 2009
  • The consumer acceptance of food is not only affected by the sensory characteristics of food but also by the non-food factors, including food experience, consumption frequency, and food attitudes. Therefore, food attitude scales such as the food neophobic scale, VARSEEK scale, Dutch restrained eating scale, health taste attitude scale, etc. have been developed and effectively used to predict consumer liking and behaviors. Since the globalization of Korean food is currently one of the hottest topics in the Korean food industry, the aim of this study was to identify the tastes and flavors that may represent Korean cuisine. Additionally, an attitudinal scale for Korean taste and flavors was developed, which can then be utilized to predict a consumer's liking of Korean food. In the first stage of the experiment, the representative taste and flavors of Korean cuisine was surveyed by a Korean culinary expert group (n=23) and general consumers (n=62). As a result of these surveys, 4 types of flavors, hot pepper flavor, 'goso' flavor, garlic flavor, and fermented flavor were shown to be the most representative flavors of Korean cuisine. Based on these results, the second stage of the experiment was carried out to develop an attitudinal scale for Korean style flavors. Eleven to 17 questionnaires were developed for each of the 4 types of flavors. The survey consisted of a total of 53 questionnaires and 154 female consumers and 158 male consumers participated in the survey. The data was analyzed by factor analysis. For each type of flavor, the final attitudinal questionnaires were selected based on the following criteria: 1. high absolute factor loading value, 2. carrying clear meaning of the corresponding flavor attitude, and 3. delivering the meaning sufficiently when translated into other language. The final Korean style flavor attitude scale consisted of 7 hot pepper flavor, 6 'goso' flavor, 6 garlic flavor, and 7 fermented flavor questionnaires. In the next step of this study, experiments will be carried out to validate the Korean style flavor attitude scale.

Prediction of Postoperative Lung Function in Lung Cancer Patients Using Machine Learning Models

  • Oh Beom Kwon;Solji Han;Hwa Young Lee;Hye Seon Kang;Sung Kyoung Kim;Ju Sang Kim;Chan Kwon Park;Sang Haak Lee;Seung Joon Kim;Jin Woo Kim;Chang Dong Yeo
    • Tuberculosis and Respiratory Diseases
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    • v.86 no.3
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    • pp.203-215
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    • 2023
  • Background: Surgical resection is the standard treatment for early-stage lung cancer. Since postoperative lung function is related to mortality, predicted postoperative lung function is used to determine the treatment modality. The aim of this study was to evaluate the predictive performance of linear regression and machine learning models. Methods: We extracted data from the Clinical Data Warehouse and developed three sets: set I, the linear regression model; set II, machine learning models omitting the missing data: and set III, machine learning models imputing the missing data. Six machine learning models, the least absolute shrinkage and selection operator (LASSO), Ridge regression, ElasticNet, Random Forest, eXtreme gradient boosting (XGBoost), and the light gradient boosting machine (LightGBM) were implemented. The forced expiratory volume in 1 second measured 6 months after surgery was defined as the outcome. Five-fold cross-validation was performed for hyperparameter tuning of the machine learning models. The dataset was split into training and test datasets at a 70:30 ratio. Implementation was done after dataset splitting in set III. Predictive performance was evaluated by R2 and mean squared error (MSE) in the three sets. Results: A total of 1,487 patients were included in sets I and III and 896 patients were included in set II. In set I, the R2 value was 0.27 and in set II, LightGBM was the best model with the highest R2 value of 0.5 and the lowest MSE of 154.95. In set III, LightGBM was the best model with the highest R2 value of 0.56 and the lowest MSE of 174.07. Conclusion: The LightGBM model showed the best performance in predicting postoperative lung function.

Comparison of Laparoscopic and Open Gastrectomy for Patients With Gastric Cancer Treated With Neoadjuvant Chemotherapy: A Multicenter Retrospective Study Based on the Korean Gastric Cancer Association Nationwide Survey

  • Seul Ki Oh;Chang Seok Ko;Seong-A Jeong;Jeong Hwan Yook;Moon-Won Yoo;Beom Su Kim;In-Seob Lee;Chung Sik Gong;Sa-Hong Min;Na Young Kim;the Information Committee of the Korean Gastric Cancer Association
    • Journal of Gastric Cancer
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    • v.23 no.3
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    • pp.499-508
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    • 2023
  • Purpose: Despite scientific evidence regarding laparoscopic gastrectomy (LG) for advanced gastric cancer treatment, its application in patients receiving neoadjuvant chemotherapy remains uncertain. Materials and Methods: We used the 2019 Korean Gastric Cancer Association nationwide survey database to extract data from 489 patients with primary gastric cancer who received neoadjuvant chemotherapy. After propensity score matching analysis, we compared the surgical outcomes of 97 patients who underwent LG and 97 patients who underwent open gastrectomy (OG). We investigated the risk factors for postoperative complications using multivariate analysis. Results: The operative time was significantly shorter in the OG group. Patients in the LG group had significantly less blood loss than those in the OG group. Hospital stay and overall postoperative complications were similar between the two groups. The incidence of Clavien-Dindo grade ≥3 complications in the LG group was comparable with that in the OG group (1.03% vs. 4.12%, P=0.215). No statistically significant difference was observed in the number of harvested lymph nodes between the two groups (38.60 vs. 35.79, P=0.182). Multivariate analysis identified body mass index (odds ratio [OR], 1.824; 95% confidence interval [CI], 1.029-3.234; P=0.040) and extent of resection (OR, 3.154; 95% CI, 1.084-9.174; P=0.035) as independent risk factors for overall postoperative complications. Conclusions: Using a large nationwide multicenter survey database, we demonstrated that LG and OG had comparable short-term outcomes in patients with gastric cancer who received neoadjuvant chemotherapy.

The study on the measurement of formaldehyde in saliva and urine by GC-MS (가스크로마토그래프-질량분석기에 의한 타액 및 뇨 중 포름알데하이드 분석법 연구)

  • Shin, Ho-Sang;Ahn, Hye-Sil
    • Analytical Science and Technology
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    • v.19 no.2
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    • pp.149-154
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    • 2006
  • A gas chromatography-mass spectrometric method was developed for the determination of formaldehyde in urine and saliva. In a 20 mL glass tube, 0.2 mL of urine or saliva was taken. Further, 1.8 mL of 0.1 M HCl, 0.1 mL of 2,000 mg/L 2,4-dinitrophenyl hydrazine and $20{\mu}l$ of 500 mg/L acetone-$d_6$ as internal standard were added in the tube and sealed tightly with cap. The solution was shaken for 20 min at room temperature and extracted using 4 mL of toluene. The extract was concentrated and redissolved with $100{\mu}l$ of acetonitrile, and then measured by gas chromatography-mass spectrometer (selected ion monitoring). The detection limit was 2.0 ng/mL and 0.5 ng/mL in saliva and urine, respectively. The calibration curves showed good linearity with r = 0.997 and 0.998 for saliva and urine, respectively. The method was used to analyze formaldehyde in rat urine after oral exposure. The developed method may be use ful to the monitoring for formaldehyde exposure in human.

Study of sweat content analysis and latent fingerprint developing (땀의 성분 분석과 잠재지문 현출에 관한 연구)

  • Choi, Mi-Jung;Sun, Yale-Shik;Kim, Chang-Seong;Choi, Man-Sik;Sung, Nack-Do;Park, Sung-Woo
    • Analytical Science and Technology
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    • v.20 no.2
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    • pp.147-154
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    • 2007
  • Sweat contents were investigated for using those data to forensic purpose. The experiments of identifying sweat contents were as follow: 1) measurement of amino acids (aspartic acid, serine, glycine etc) by HPLC, 2) anions ($Cl^-$, $F^-$, and $SO{_4}^{2-}$) by IC and 3) trace elements (Cu, Zn, Li, B, etc.) by ICP-MS. Amino acid contents in sweat are varied with individual samples and glycine, threonine, alanine, valine and histidine are detected as the prime one. The detected anions are $Cl^-$(2167~4073 ppm) and $F^-$(454~582 ppm) mostly. Trace elements of Rb, Zn and Cu are detected and those concentrations are relatively very high. The compositions of sweat can be influenced by various factors (diet, anthropometric, characteristics, physical fitness, age, gender and the state of the health).

A study on environmental status, FIM and Illness intrusiveness of home stayed stroke patients (재가 노졸중 환자의 환경상태, 기능적 독립, 질병으로 인한 장애영향에 관한 연구)

  • Kim, Keum Soon;Roh, Kook Hee
    • 한국노년학
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    • v.25 no.2
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    • pp.143-154
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    • 2005
  • This study was conducted to examine the environmental status, FIM(Function Independence Measure), Illness intrusiveness of home stayed stroke patients. Data were collected on 145 patients living in K city and the neighborhood located in southern part of Korea. The data were analyzed by means of SPSS program. Results : In assessment of environmental safety, 46.2%(67) felt unsafe around their residential area. The most dangerous facilities in their residence was stairs(58.2%), gas/electric facilities(14.9%). For sanitary problems, 28.2%(41) felt they have problems at their home. The most important problems were outdoor polluted toilet(22.0%) and scattered and dirty residential circumstances(22.0%). The average FIM score was 74.52(4.14) of total score 126(7). In motor area FIM was lowest at stair walking(3.01) and bathing(3.16). In cognitive area FIM was lowest at social activities(3.36). The mean score of Illness intrusiveness was 58.86(4.52) of total score 91(7). The major area largely impacted by stroke were health(5.61), working(5.68), active leisure activities(5.56). There was significant reverse correlation between FIM and illness intrusiveness(r=-0.66, p=0.00). Conclusion : It was needed environmental improvement and rehabilitation program for stroke patients, and repeated follow up study.

An Examination of the Effectiveness of Crisis Response Strategies for Repairing Competence and Integrity Violations

  • Sung, Yen-yi;Lee, Han-joon;Park, Jong-chul
    • Asia Marketing Journal
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    • v.15 no.1
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    • pp.129-154
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    • 2013
  • Product-harm crises, which are connected to defective or dangerous products, are perceived as the most common threats to a company. Product harm crises can distort long standing favorable equality perceptions, tarnish a company's reputation, cause major revenue and market-share losses, lead to costly product recalls, and devastate a carefully nurtured brand equity. However, in spite of the devastating impact of product-harm crises, little systematic research exists to asses its marketing consequences. So, the purpose of this study is to investigate how Koreans react to the crisis response in the aftermath of different crises(competence violation vs. integrity violation) and inspire additional research in crisis communication. This study has three main findings which run counter to the assumptions of Kim et al.(2007). Namely, the current study expands on the research of Kim et al. (2004, 2007) by examining how companies repair customers' trust and corporate attitude after crises. Different from previous studies, this study assumes that apology for an integrity-based crisis is the most appropriate way to repair consumer trust and corporate attitude. As for competence-based crisis, similarly, apology for competence-based crisis can be more successful repairing consumer trust and corporate attitude. Concerning silence strategy, remaining silent dose not admit or deny guilt right away, but instead of asking the perceiver to withhold judgment, suggesting that, silence could be expected to be superior to apology but inferior to denial. Finally, apology for competence violation will be expected to bemore effective than apology for integrity violation. Research conceptual model was as follows: According to the results, apology is found to be the most effective strategy to repair corporate attitude no matter the crisis is perceived as a violation of competence or integrity. Second, company may consider keeping silent as a desirable response because they does not admit nor deny responsibility but ask the public to withhold judgment. However, the result of this study shows that, in the overall crisis situations, silence strategy did not differ significantly from the denial strategy, which suggested that the public wants explanation instead of uncertainty. Third, there was the interaction effect between crisis type and crisis response strategies. In this study, apology is more effective for the competence violated situation in terms of regaining consumer trust and repairing their attitude toward company, while the apology's effectiveness is lower for the integrity-violated situation. More specifically, when the crisis is perceived due to company's lack of ability(competence violation), consumer's trust belief and attitude toward the company is more easily to repair when the company issued a sincere apology. Damaged product is perceived less intentional so participants are more likely to give the company second chance when they apology to the public. By contrast, exaggerated advertisement(integrity violation) is perceived intentionally and thus makes participants angrier toward the accused company. Although apology is perceived as the most effective strategy, when issuing apology, it also means the company admitted their intention. Therefore, in this kind of crisis situation, trust repair needs not only a sincere apology but additional efforts.

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