• Title/Summary/Keyword: combination method

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Effect of Pre-treatment and Packaging Method on Freshness Prolongation of Spring Kimchi Cabbage during Low Temperature Storage (봄배추의 전처리 및 포장방법이 저온저장 중 선도유지에 미치는 효과)

  • Se-Jin Park;Ji-Young Kim;Andri Jaya Laksana;Byeong-Sam Kim
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.29 no.2
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    • pp.119-128
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    • 2023
  • This study was examined for investigating the quality changes of spring kimchi cabbage under various treatments (pre-drying/pre-cooling, packaging types, and stacking and loading in container and pallete in the storage room) during cold storage. The results showed that control (upward stacking without pre-drying/pre-cooling and HDPE or PVC film cover) was increased significantly in weight loss and trimming loss, compared to other treatments such as DPDH (downard stacking + pre-drying + HDPE), DPDP (downard stacking + pre-drying + PVC), DPCH (downnard stacking + pre-cooling + HDPE), and UPCH (upward stacking + pre-cooling +HDPE) during storage for three months. In Sensory evaluation, judging from marketable properties, the desirable appearance of spring kimchi cabbage with the modified pallet-unit MA packed, PE, and PVC film wrapping could be maintained until 9 weeks after pre-drying/pre-cooling. Meanwhile, the control without any treatments after 6 weeks, the sensory score was declined, significantly. In general, the low temperature (10℃ and 2℃) of pre-treatment with combination of plastic film packaging in spring kimchi cabbage storage could inhibit the physiological activity and reduce the direct exposure of environmental cold air in the storage. Therefore, these two variables were the key points for extending the shelf-life of spring kimchi cabbage.

A Study on the Numerical Analysis Methods for Predicting Strength Test Result of Box Girder under Bending Moment (휨 모멘트를 받는 박스거더 구조 강도 실험에 대한 수치해석 방법에 관한 연구)

  • Myung-Su Yi;Joo-Shin Park
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.5
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    • pp.488-496
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    • 2023
  • Ship and bridge structures are a type of long box-shaped structure, and resistance to vertical bending moment is a key factor in their structural design. In particular, because box girders are repeatedly exposed to irregular wave loads for a long time, the continuous collapse behavior of structural members must be accurately predicted. In this study, plastic collapse behavior, including buckling according to load changes of the box girder receiving pure bending moments, was analyzed using a numerical analysis method. The analysis targets were selected as three box girders used in the Gordo experiment. The cause of the difference was considered by comparing the results of the structural strength experiment with those of non-linear finite element analysis. This study proposed a combination of the entire and local sagging shape to reflect the effect of the initial sagging caused by welding heat that is inevitably used to manufacture carbon steel materials. The procedures reviewed in the study and the contents of the initial sagging configuration can be used as a good guide for analyzing the final strength of similar structures in the future.

Study on the Evaluation of Ship Collision Risk based on the Dempster-Shafer Theory (Dempster-Shafer 이론 기반의 선박충돌위험성 평가에 관한 연구)

  • Jinwan Park;Jung Sik Jeong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.29 no.5
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    • pp.462-469
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    • 2023
  • In this study, we propose a method for evaluating the risk of collision between ships to support determination on the risk of collision in a situation in which ships encounter each other and to prevent collision accidents. Because several uncertainties are involved in the navigation of a ship, must be considered when evaluating the risk of collision. We apply the Dempster-Shafer theory to manage this uncertainty and evaluate the collision risk of each target vessel in real time. The distance at the closest point approach (DCPA), time to the closest point approach (TCPA), distance from another vessel, relative bearing, and velocity ratio are used as evaluation factors for ship collision risk. The basic probability assignments (BPAs) calculated by membership functions for each evaluation factor are fused through the combination rule of the Dempster-Shafer theory. As a result of the experiment using automatic identification system (AIS) data collected in situations where ships actually encounter each other, the suitability of evaluation was verified. By evaluating the risk of collision in real time in encounter situations between ships, collision accidents caused by human errora can be prevented. This is expected to be used for vessel traffic service systems and collision avoidance systems for autonomous ships.

A Survey on Korean Medicine Doctors' Recognition and Treatment for Developing Korean Medicine Clinical Practice Guideline of Female Infertility (여성 난임 한의표준임상진료지침 개작을 위한 한의사의 인식과 치료에 관한 실태조사)

  • Hyo-Jeong Jung;Dong-Il Kim;Su-Ji Choi;Su-In Hwang;Young-Jin Yoon;Jang-Kyung Park
    • The Journal of Korean Medicine
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    • v.43 no.3
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    • pp.122-138
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    • 2022
  • Objectives: This study was conducted to develop a Korean Medicine(KM) Clinical Practice Guidelines(CPG) of female infertility. We conducted this questionnaire survey to reflect the experiences of Korean Medicine doctors(KMD) and clinical field in Korea. Method: We sent a questionnaire survey to KMD belonging to the Association of Korean Medicine by e-mail. We received 665 responds, and analyzed the answers. Results: 51.2% of respondents knew the previously developed CPG of female infertility, and 18.3% actually used. 83.3% agreed about the necessity of CPG of female infertility, and 80.3% had practical use plan. 90.2% of respondents treated less than 5 infertility woman for a month. 22.7% of respondents treated 50% of patients with collaborative treatment of KM and Western medical treatments. The main age group of patients was '35~40 years'(54.7%), and the most common cause was unexplained infertility(61.7%). The most common pattern identification of female infertility patients was Kidney deficiency(55.4%). KMD used 'a combination of decoction of herbal medicine, acupuncture and moxibustion treatment' the most(43%), and 'a decoction of herbal medicine treatment alone' was next(35%). 84.2% conducted lifestyle modification education about diet, stress, exercise etc. Conclusion: We figured out Korean Medicine doctors' recognition about CPG of female infertility, preference of treatments, and also characteristics of patients visiting Korean Medical clinics to make a practical CPG reflecting clinical situation.

Effect of Water Management on Greenhouse Gas Emissions from Rice Paddies Using a Slow-release Fertilizer (완효성 비료를 시용한 논에서의 물관리에 따른 온실가스 배출량 평가)

  • Eun-Bin Jang;Hyun-Chul Jeong;Hyo-Suk Gwon;Hyoung-Seok Lee;Hye-Ran Park;Jong-Mun Lee;Taek-Keun Oh;Sun-Il Lee
    • Korean Journal of Environmental Agriculture
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    • v.42 no.2
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    • pp.112-120
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    • 2023
  • Methane (CH4) and nitrous oxide (N2O) are significant contributors to greenhouse gas (GHG) emissions from rice fields. Mid-summer drainage is a commonly practiced water management technique that reduces CH4 emissions from rice fields. Slow-release fertilizers gradually release nutrients over an extended period and have been shown to reduce N2O emissions. However, the combined effect of slow-release fertilizer and water management on GHG emissions remains unclear. This study compared GHG emissions from a rice paddy subjected to mid-summer drainage for 10 days (control) with that of a rice paddy subjected to prolonged mid-summer drainage for 20 days combined with slow-release fertilizer (W+S). Gas sampling was conducted weekly using a closed chamber method. During the rice cultivation period, cumulative CH4 and N2O emissions were reduced by 12.3% and 16.2%, respectively, in the W+S treatment compared to the control. Moreover, the W+S treatment exhibited a 1.9% increase in grain yield compared to the control. Under experimental conditions, slow-release fertilizers, in combination with prolonged mid-summer drainage, proved to be the optimal approach for achieving high crop yield while reducing GHG emissions. This represents an effective strategy to mitigate GHG emissions from rice paddy fields.

Measurements of Trimethylamine (TMA) in air by Tedlar bag sampling and SPME analysis (환경대기 중 Trimethylamine (TMA)의 측정: Tedlar bag 방식의 채취와 SPME 분석법의 특성 연구)

  • Kim, K.H.;Hyum, S.H.;Im, M.S.
    • Analytical Science and Technology
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    • v.19 no.1
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    • pp.96-102
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    • 2006
  • Trimethylamine (TMA) is one of the difficult odorous compounds for the collection and analysis. Although sulfuric acid absorption and/or sulfuric acid impregnated filter method are commonly recommended for its sampling, these methods also suffer from difficulties involved in sample treatment and operational procedures. Hence, as an ancillary approach to measure TMA, we investigated the combination of bag sampling and SPME analysis for TMA measurements. For the purpose of our study, we investigated the following three subjects: 1) temporal variability of standard storage, 2) bag loss effect of TMS, and 3) TMA loss due to repetitive analysis of an identical bag sample. According to our storage test up to 7 or 20 dyas, TMA loss were found to occur up to 40 to 50% within relatively short period of up to 48 hrs depending on its concentration ranges. When the tests were made for bag loss by transferring TMA standards across different size bags, we were able to find that the extent of bag loss are not significant with 5 to 20% loss rate. Finally, the TMA sorptive loss via its exposure to SPME fiber was generally estimated to run from 2 to 3%.

Natural isotopes and trace element analyses in glass samples (판유리 시료에서 동위원소 및 미량원소 분석법)

  • Min, Ji-Sook;Heo, Sangcheol;Kim, Jae-Guin;Kim, Eun-Ho;Kim, Dong-Wook;Chung, Hee-Sun
    • Analytical Science and Technology
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    • v.20 no.3
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    • pp.219-226
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    • 2007
  • Glass is frequently encountered as types of materials that are submitted to forensic science laboratories as a result of trace evidence transfers. The repeatability and the reproducibility of trace element analysis were presented. An analysis of variance (ANOVA) was performed on laser ablation inductively coupled plasma spectrometric analyses of the fragments to identify the source. Pairwise comparisons were completed for all samples. In a pairwise comparison, each sample was compared to each other for a possible [n(n-1)/2] (n : numbers of the samples) total comparison to associate/discriminate samples using Tukey's HSD method. The aim of this study was to determine the utility of LA-ICP-MS for multi-element analysis of forensic samples. The 12 glass fragments from two manufacturers were collected and analyzed to identify the source. An analysis of variance (ANOVA) was performed on 31 elements in NIST 612 Trace elements in Glass. Elements were classified into four categories defined by the combination of precision and variation of inter-samples. We selected 11 elements, 209Bi, 90Zr, 121Sb, 178Hf, 59Co, 238U, 208Pb, 140Ce, 118Sn, 49Ti and 137Ba. 6 pairs out of 66 possible pairs were not distinguished when compared by 137Ba (p<0.05). However, all samples were distinguished using both 49Ti and 137Ba (p<0.05). In conclusion, multi-elemental analysis with LA-ICP-MS is a potential tecnique for the discrimination of forensic samples.

Dewatering of Sewage Sludge by Electrokinetics (동전기를 이용한 슬러지 탈수에 관한 연구)

  • Kim, Ji Tae;Won, Se Yeon;Cho, Won Cheol
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.6B
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    • pp.661-667
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    • 2006
  • In this study, an experiment of sewage sludge dewatering is carried by using electrokinetic method, and the electrokinetic dewatering efficiency of digested sludge is analyzed. Digested sludge without coagulants is selected and gravitational and pressing dewatering methods are applied in combination with electro-osmotic and electro-osmotic pulse technology. After the test of digested sludge, dewatering test of thickened sludge is carried to evaluate the electrokinetic dewatering feasibility of thickened sludge. Under the condition of constantly applied voltage, however, electrical resistance increases with decreasing of water content so that dewatering rate decreases with time. To reduce such a hindrance caused by constantly applied voltage, electro-osmotic pulse technology which is considered to reduce the difference of water content with height, is applied. For the application of electro-osmotic pulse, the dewatered flow rate and the dewatered volume became more increasing from the middle of the dewatering process than that of continuous voltage. Through the test of thickened sludge, electro-osmotic dewatering combined with gravitational and expression also showed high dewatering rate, which proved the possibility of using electrokinetic dewatering.

Analysis of Permeability Characteristics for Fly Ash Concrete According to Aggregate Size and Mixing Ratio (골재크기와 배합비에 따른 플라이애시 콘크리트의 투기특성 분석)

  • Eun-A Seo;Do-Gyeum Kim;Chul-Woo Jung;Ho-Jae Lee
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.11 no.4
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    • pp.400-406
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    • 2023
  • In this study, the relationship between the material properties and air permeability characteristics was examined, an experimental method to analyze the air permeability characteristics was presented, and experimental results were derived. The effects of compressive strength and apparent density of hardened concrete on air permeability characteristics were evaluated experimentally. Focusing on the mix proportions used in nuclear power plant concrete structures, concrete test specimens were manufactured and air permeability characteristics were measured according to changes in binder, maximum aggregate size, and water-binder ratio. The apparent density was over 2,400 kg/m3 for the OPC mix and the FA-35 mix, and the air permeability for both mixes were low, in the range of 0.1-0.2 L/min. On the other hand, in the case of the combination of FA-40, FA-45, and FA-M, the apparent density was measured to be less than 2,400 kg/m3 and the air permeability was measured to be more than 0.3 L/min, experimentally verifying that the apparent density is an important factor in air permeability characteristics.

Assessment of Combined Administration of Hypoglycemic Agents and Herbal Extracts (Pyeongwi-san or HyangsaPyongwi-san) on Blood Glucose Levels in Type 2 Diabetes Mellitus: A Retrospective Study (표준 치료를 받고 있는 제2형 당뇨병 환자에서 혈당강하제와 평위산 및 향사평위산 병용 투여가 혈당에 미치는 영향 및 안정성 연구)

  • Woo-nyoung Jung;Seung-hyun Oh;Mee-ryoung Song;Ji-won Noh;Young-min Ahn;Se-young Ahn;Byung-cheol Lee
    • The Journal of Internal Korean Medicine
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    • v.44 no.4
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    • pp.661-674
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    • 2023
  • Abstract: This retrospective study delved into the effects and safety considerations associated with the concomitant usage of hypoglycemic agents and herbal extracts, specifically Pyeongwi-san (PWS) or HyangsaPyongwi-san (HSPWS) in the context of type 2 diabetes mellitus management. Methods: The investigation involved 38 inpatients with type 2 diabetes mellitus who received PWS or HSPWS treatment at Kyung Hee University Korean Medical Hospital from January 2012 to December 2022. By investigating clinical attributes and conducting laboratory assessments, this study aimed to discern the impact of these herbal extracts on blood glucose levels, encompassing fasting blood sugar (FBS) and mean 2-hour postprandial glucose (PP2) levels. Furthermore, the safety profile of the herbal extracts was assessed by comparing liver function indicators, including aspartate aminotransferase (AST), alanine aminotransferase (ALT), and γ-glutamyl transferase (GGT), alongside kidney function markers, such as blood urea nitrogen (BUN) and creatinine (Cr). Results: Following the administration of the herbal extracts, no statistically significant alterations in FBS and mean PP2 levels emerged compared to the baseline levels. Notably, the safety evaluation revealed no significant differences in liver and kidney function parameters following herbal extract administration. Conclusion: The results of this research indicate that using PWS or HSPWS alongside hypoglycemic medications could be a beneficial additional method for addressing digestive symptoms in individuals with type 2 diabetes mellitus. Notably, this combination seems to have no negative interactions with other drugs.