• Title/Summary/Keyword: Safety Performance

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Outcomes of partially covered self-expandable metal stents with different uncovered lengths in endoscopic ultrasound-guided hepaticogastrostomy: a Japanese retrospective study

  • Takeshi Okamoto;Takashi Sasaki;Tsuyoshi Takeda;Tatsuki Hirai;Takahiro Ishitsuka;Manabu Yamada;Hiroki Nakagawa;Takafumi Mie;Takaaki Furukawa;Akiyoshi Kasuga;Masato Ozaka;Naoki Sasahira
    • Clinical Endoscopy
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    • v.57 no.4
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    • pp.515-526
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    • 2024
  • Background/Aims: The optimal length of the uncovered portion of partially covered self-expandable metal stents (PCSEMSs) used in endoscopic ultrasound-guided hepaticogastrostomy (EUS-HGS) remains unclear. This study investigated the safety and efficacy of PCSEMSs with different uncovered lengths, with a focus on stent migration and time to recurrent biliary obstruction (RBO). Methods: Outcomes of patients undergoing EUS-HGS using PCSEMSs with 5-mm and 20-mm uncovered portions at our institution from January 2016 to December 2021 were compared. Results: Sixty-two patients underwent EUS-HGS using PCSEMS (5/20-mm uncovered portions: 32/30). Stent migration occurred only in the 5-mm group. There were no differences in RBO rates (28.1% vs. 40.0%) or median time to RBO (6.8 vs. 7.1 months) between the two groups. Median overall survival (OS) was longer in the 20-mm group (3.1 vs. 4.9 months, p=0.037) due to the higher number of patients that resumed chemotherapy after EUS-HGS (56.7% vs. 28.1%, p=0.029). Good performance status, absence of hepatic metastases, and chemotherapy after EUS-HGS were independent predictors of longer OS. Conclusions: No migration was observed in patients treated with PCSEMS with 20-mm uncovered portions. Patients treated with PCSEMS with 20-mm uncovered portions performed at least as well as those treated with 5-mm uncovered portions in all material respects.

Improving the Cycle Performance of Li Metal Secondary Batteries Using Three-Dimensional Porous Ag/VGCF-Coated Separators (3D 다공성 구조의 Ag-VGCF 코팅 분리막을 이용한 리튬금속 이차전지 수명향상)

  • Beom-Hui Lee;Dong-Wan Ham;Ssendagire Kennedy;Jeong-Tae Kim;Sun-Yul Ryou
    • Journal of the Korean Electrochemical Society
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    • v.27 no.3
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    • pp.88-96
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    • 2024
  • Lithium metal has garnered attention as a promising anode active material thanks to its high specific capacity, energy density, and the lowest reduction potential. However, the formation of dendrites, dendritic crystals that arise during the charge and discharge process, has posed safety and lifetime stability challenges. To resolve this, our study has introduced a novel separator design. This separator features a composite coating of vapor-grown carbon fiber, a conductive material in nanofibers, and silver. We have meticulously studied the impact of this innovative separator on the electrochemical properties of the lithium metal anode, unveiling promising results. To confirm the synergistic effect of VGCF and Ag, a separator with no surface treatment and a separator with only VGCF coated on one side were prepared and compared with the Ag-VGCF-separator. In the case of the bare separator, the Li metal surface is covered with dendrites during the initial charge and discharge process. In contrast, both the VGCF-separator and the Ag-VGCF-separator show Li precipitation inside the conductive coating layer coated on the separator surface. Additionally, the Ag-VGCF-separator showed a more uniform precipitate shape than the VGCF-separator. As a result, the Ag-VGCF-separators show improved electrochemical properties compared to the bare separators and the VGCF-separators.

Fire Risk Prediction and Fire Risk Rating Evaluation of Four Wood Types by Comparing Chung's Equation-IX and Chung's Equation-XII (Chung's Equation-IX과 Chung's Equation-XII의 비교에 의한 목재 4종의 화재위험성 예측 및 화재위험성 등급 평가)

  • JiSun You;Yeong-Jin Chung
    • Applied Chemistry for Engineering
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    • v.35 no.3
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    • pp.200-208
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    • 2024
  • Chung's equations-IX and Chung's equation-XII were utilized to predict the fire risk and evaluate fire risk ratings for four types of wood: camphor, cherry, rubber, and elm trees. The combustion tests were conducted using a cone calorimeter test method by ISO 5660-1 standards. The fire risk and fire risk rating (FRR) were compared for Fire Risk Index-IX (FRI-IX) and Fire Risk Index-XII (FRI-XII). The results yielded Fire Performance Index-XI (FPI-XI) ranging from 0.08 to 11.48 and Fire Growth Index-XI (FGI-XI) ranging from 0.67 to 111.89. The Fire Risk Index-XII (FRI-XII), indicating fire risk rating, exhibited an increasing order of cherry (0.45): Grade A (Ranking 5) < PMMA (1): Grade A (Ranking 4) < elm (1.23): Grade A (Ranking 3) < rubber (1.56): Grade A (Ranking 2) << camphor (148.23): Grade G (Ranking 1). Additionally, the fire risk index-IX (FRI-IX) was cherry (0): Grade A (Ranking 3) ≈ rubber (0): Grade A (Ranking 3) ≈ elm tree (0): Grade A (Ranking 3) < PMMA (1): Grade A (Ranking 2) << camphor tree (66.67): Grade G (Ranking 1). In general, camphor was found to have the highest fire risk. In conclusion, although the expression of the index is different as shown based on the standards of FRI-IX and FRI-XII, predictions based on fire risk assessment of combustible materials showed similar trends.

Application of Laboratory Furniture Drawer Material Development Process Using TRIZ and ARIZ-85C (TRIZ와 ARIZ-85C를 활용한 실험실 가구 서랍 재질 개발 프로세스 적용 사례)

  • Youngjin SON;Sungmin BAE
    • Journal of Korean Society for Quality Management
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    • v.52 no.3
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    • pp.575-591
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    • 2024
  • Purpose: Storage furniture in a laboratory where chemical experiments are conducted should satisfy both the chemical reactivity and stability required in the experimental environment, commonality with general households, and economic feasibility for the mass production system. Therefore, the development of storage furniture used in the laboratory should be done quickly through a process verified by utilizing various ideas and using a method suitable for the special environment called the laboratory. This study deals with the process of developing materials for inner drawers of laboratory furniture that meet these requirements. Methods: TRIZ methodology and ARIZ-85C process were applied to satisfy the requirements arising from the product development process, ARIZ process was applied step by step to resolve the contradictions that occurred during the development process, and 40 invention principles and ideal solutions (Ideal Final Results: IFR) were derived through clear analysis of the problem to select materials suitable for the special environment of the laboratory. Results: This study focused on the selection of materials that meet the durability and chemical stability required in the special environment of laboratory furniture. Through this, various solutions were sought with the aim of reducing cost and increasing productivity, and the process of maximizing useful functions and minimizing irrational parts in use was focused on TRIZ's contradiction resolution method. As a result, we found a way to improve the performance and efficiency of laboratory furniture through the selection of optimized furniture materials and problem solving methods. Conclusion: In this study, a methodology for the development of efficient and safe laboratory furniture materials was found and verified. In the use of furniture products in a laboratory, corrosion or damage caused by chemical generators may occur, making it difficult to use as a product. As a result, a method to reduce cost and increase productivity while maintaining the durability and chemical stability of laboratory furniture was found, and by finding a solution to the two relationships between chemical safety and production efficiency in the process of selecting materials for optimized furniture materials, and applying the ARIZ development process, the effectiveness of the product development process in a special environment could be verified.

Prediction of Fire Risk and Fire Risk Grade of Five Wood Species by Chung's Equation-IX and Chung's Equation-XII (Chung's equation-IX 및 Chung's equation-XII에 의한 목재 5종의 화재위험성과 화재위험성등급 예측)

  • JiSun You;Yeong-Jin Chung
    • Applied Chemistry for Engineering
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    • v.35 no.5
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    • pp.458-467
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    • 2024
  • Chung's equation-IX and Chung's equation-XII were utilized to predict the fire risk and evaluate fire risk ratings for five types of wood: white ash, hard maple, willow, fraxinus mandschurica, and sagent cherrys. The combustion tests were conducted using a cone calorimeter test method by ISO 5660-1 standards. The fire risk and fire risk rating (FRR) were compared with fire risk index-IX (FRI-IX) and fire risk index-XII (FRI-XII). The results yielded a fire performance index-XI (FPI-XI) ranging from 0.44 to 1.05 and a fire growth index-XI (FGI-XI) ranging from 0.89 to 3.11. Also, the fire risk index-XII (FRI-XII), indicated fire risk rating, exhibited an increasing order of sagent cherry (0.85): Grade A ≈ PMMA (1): Grade A ≈ white ash (1.22): Grade A ≈ hard maple (1.53): Grade A < willow (4.00): Grade C < faxinus mandschurica (7.07): Grade D. Additionally, the fire risk index-IX (FRI-IX) was PMMA (1): Grade A ≈ hard maple (2.28): Grade A ≈ sagent cherry (3.24): Grade A < white ash (5.73): Grade B < fraxinus mandschurica (10.29): Grade C ≪ willow (48.30): Grade G. In general, the willow and fraxinus mandschurica showed the highest fire risk. In conclusion, although the expression of the index is different as shown based on the criteria of FRI-IX and FRI-XII, predictions based on fire risk assessment of combustible materials showed a similar tendency.

Glass Dissolution Rates From MCC-1 and Flow-Through Tests

  • Jeong, Seung-Young
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.257-258
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    • 2004
  • The dose from radionuclides released from high-level radioactive waste (HLW) glasses as they corrode must be taken into account when assessing the performance of a disposal system. In the performance assessment (PA) calculations conducted for the proposed Yucca Mountain, Nevada, disposal system, the release of radionuclides is conservatively assumed to occur at the same rate the glass matrix dissolves. A simple model was developed to calculate the glass dissolution rate of HLW glasses in these PA calculations [1]. For the PA calculations that were conducted for Site Recommendation, it was necessary to identify ranges of parameter values that bounded the dissolution rates of the wide range of HLW glass compositions that will be disposed. The values and ranges of the model parameters for the pH and temperature dependencies were extracted from the results of SPFT, static leach tests, and Soxhlet tests available in the literature. Static leach tests were conducted with a range of glass compositions to measure values for the glass composition parameter. The glass dissolution rate depends on temperature, pH, and the compositions of the glass and solution, The dissolution rate is calculated using Eq. 1: $rate{\;}={\;}k_{o}10^{(ph){\eta})}{\cdot}e^{(-Ea/RT)}{\cdot}(1-Q/K){\;}+{\;}k_{long}$ where $k_{0},\;{\eta}$ and Eaare the parameters for glass composition, pH, $\eta$ and temperature dependence, respectively, and R is the gas constant. The term (1-Q/K) is the affinity term, where Q is the ion activity product of the solution and K is the pseudo-equilibrium constant for the glass. Values of the parameters $k_{0},\;{\eta}\;and\;E_{a}$ are the parameters for glass composition, pH, and temperature dependence, respectively, and R is the gas constant. The term (1-Q/C) is the affinity term, where Q is the ion activity product of the solution and K is the pseudo-equilibrium constant for the glass. Values of the parameters $k_0$, and Ea are determined under test conditions where the value of Q is maintained near zero, so that the value of the affinity term remains near 1. The dissolution rate under conditions in which the value of the affinity term is near 1 is referred to as the forward rate. This is the highest dissolution rate that can occur at a particular pH and temperature. The value of the parameter K is determined from experiments in which the value of the ion activity product approaches the value of K. This results in a decrease in the value of the affinity term and the dissolution rate. The highly dilute solutions required to measure the forward rate and extract values for $k_0$, $\eta$, and Ea can be maintained by conducting dynamic tests in which the test solution is removed from the reaction cell and replaced with fresh solution. In the single-pass flow-through (PFT) test method, this is done by continuously pumping the test solution through the reaction cell. Alternatively, static tests can be conducted with sufficient solution volume that the solution concentrations of dissolved glass components do not increase significantly during the test. Both the SPFT and static tests can ve conducted for a wide range of pH values and temperatures. Both static and SPFt tests have short-comings. the SPFT test requires analysis of several solutions (typically 6-10) at each of several flow rates to determine the glass dissolution rate at each pH and temperature. As will be shown, the rate measured in an SPFt test depends on the solution flow rate. The solutions in static tests will eventually become concentrated enough to affect the dissolution rate. In both the SPFt and static test methods. a compromise is required between the need to minimize the effects of dissolved components on the dissolution rate and the need to attain solution concentrations that are high enough to analyze. In the paper, we compare the results of static leach tests and SPFT tests conducted with simple 5-component glass to confirm the equivalence of SPFT tests and static tests conducted with pH buffer solutions. Tests were conducted over the range pH values that are most relevant for waste glass disssolution in a disposal system. The glass and temperature used in the tests were selected to allow direct comparison with SPFT tests conducted previously. The ability to measure parameter values with more than one test method and an understanding of how the rate measured in each test is affected by various test parameters provides added confidence to the measured values. The dissolution rate of a simple 5-component glass was measured at pH values of 6.2, 8.3, and 9.6 and $70^{\circ}C$ using static tests and single-pass flow-through (SPFT) tests. Similar rates were measured with the two methods. However, the measured rates are about 10X higher than the rates measured previously for a glass having the same composition using an SPFT test method. Differences are attributed to effects of the solution flow rate on the glass dissolution reate and how the specific surface area of crushed glass is estimated. This comparison indicates the need to standardize the SPFT test procedure.

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Aspect of the chief of state guard EMP (Electro Magnetic Pulse) protection system for the consideration (국가원수 경호적 측면에서의 EMP(Electro Magnetic Pulse) 방호 시스템에 대한 고찰)

  • Jung, Joo-Sub
    • Korean Security Journal
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    • no.41
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    • pp.37-66
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    • 2014
  • In recent years, with the development of computers and electronics, electronics and communication technology in a growing and each part is dependent on the cross-referencing makes all electronic equipment is obsolete due to direct or indirect damage EMP. Korea and the impending standoff North Korea has a considerable level of technologies related to the EMP, EMP weapons you already have or in a few years, the development of EMP weapons will complete. North Korea launched a long-range missile and conducted a nuclear test on several occasions immediately after, when I saw the high-altitude nuclear blackmail has been strengthening the outright offensive nuclear EMP attacks at any time and practical significance for the EMP will need offensive skills would improve. At this point you can predict the damage situation of Korea's security reality that satisfy the need, more than anything else to build a protective system of the EMP. The scale of the damage that unforeseen but significant military damage and socio-economic damage and fatalities when I looked into the situation which started out as a satellite communications systems and equipment to attack military and security systems and transportation, finance, national emergency system, such as the damage elsewhere. In General, there is no direct casualties reported, but EMP medical devices that rely on lethal damage to people who can show up. In addition, the State power system failure due to a power supply interruption would not have thought the damage would bring State highly dependent on domestic power generation of nuclear plants is a serious nuclear power plant accident in the event of a blackout phenomenon can lead to the plant's internal problems should see a forecast. First of all, a special expert Committee of the EMP, the demand for protective facilities and equipment and conduct an investigation, he takes fits into your budget is under strict criteria by configuring the contractors should be sifting through. He then created the Agency for verification of performance EMP protection after you have verified the performance of maintenance, maintenance, safety and security management, design and construction company organized and systematic process Guard facilities or secret communications equipment and perfect for the EMP, such as protective equipment maneuver system should take.

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Effects of Production Performance, Immunity and Egg Quality by Raising on Exercise Yard in Laying Hens (산란계 운동장 사육이 생산성, 면역성 및 계란의 품질에 미치는 영향)

  • Kim, Ki Soo;Lee, Suk Kyung;Choi, Young Sun;Ha, Chang Ho;Kim, Won Ho
    • Korean Journal of Poultry Science
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    • v.40 no.2
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    • pp.97-103
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    • 2013
  • The present study examined effects of production performance, immune activity and egg quality by raising on exercise yard in laying Hens, the results of which could be used as baseline data to enhance animal welfare and the safety of livestock products. A total of 90 Hy-line-Brown laying hens of 13 weeks old were used in the experiment for 38 weeks. The cage group (Cage group) was raised in a cage, where an area of $0.084m^2$ was assigned to two hens, while hens in the exercise yard $1.1m^2$ group ($1.1m^2$ group) was assigned to a combination of a chicken house ($0.11m^2$) and a exercise yard ($1.1m^2$) per a hen. Hens in the exercise yard $2.2m^2$ group ($2.2m^2$ group) was assigned to a combination of a chicken house ($0.11m^2$) and a exercise yard ($2.2m^2$) per a hen. Treatment was replicated 3 times with ten birds per replication. Ten birds were arranged according to randomized block design. While initial egg production rate was significantly higher in the Cage group, $1.1m^2$ group exhibited a slightly higher rate in the mid- and late-stage of the experiment, although the difference was not statistically significant. Exercise yard treatment groups exhibited a higher feed intake rate than the Cage group up until the hens were 39 weeks old (P<0.05), but the difference dissipated from that age on. The age at first egg in the exercise yard treatment groups was 16 days later than that for the Cage group (P<0.05), although differences in the quality of the eggs were not observed. The results of immune activity test showed that IgA in the exercise yard treatment groups was significantly higher than that in the Cage group (P<0.05). IgG, IgM, and corticosterone were also higher in the exercise yard treatment groups. The soil in exercise yard increased of organic matter and decreased of cation exchange capacity (CEC) in raised hens. In sum, raising hens in a exercise yard raise style decreased the rate of initial egg production, which was followed by a slight increase during the latter part of the experiment. The exercise yard raise hens' immune activity was heightened.

Effects of dietary supplementation with fermented spent mushroom substrates of the winter mushroom (Flammulina velutipes) on growth performance, carcass traits, and economic characteristics of Hanwoo steers (발효 팽이버섯 수확후배지의 급여 수준이 한우 거세우의 비육과 도체성적 및 경제성 분석에 미치는 영향)

  • Moon, Yea-Hwang;Cho, Woong-Ki;Kim, Hyun-Jung;Kim, Ji-Eun;Kim, Bo-Ram;Kim, Hye-Soo;Cho, Soo-Jeong
    • Journal of Mushroom
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    • v.15 no.4
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    • pp.223-228
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    • 2017
  • This study was conducted to investigate the effects of fermented spent mushroom substrates (F-SMS) of Flammulina velutipes on growth performance, carcass traits, and economic characteristics of Hanwoo steers. A yeast strain (Saccharomyces sp. UJ14) and Bacillus strain (Bacillus sp. UJ03) isolated from fresh spent mushroom substrates of Flammulina velutipes were used as probiotics to prepare F-SMS. Twenty-four Hanwoo steers (14 months old) were allocated to three dietary treatments via a randomized block design and were slaughtered at 30 months of age. These treatment groups included Control (TMR), T1 (TMR containing 10% of F-SMS) group, and T2 (TMR containing 30% of F-SMS). Body weight gain was not influenced by the experimental diets. DM and TDN intakes in the finishing period were significantly (p < 0.05) greater in group T1 than in other groups. CP intake was significantly (p < 0.05) greater in group T2 than in other groups during the whole experimental period. Among carcass traits, rib-eye area and back fat thickness tended to increase with F-SMS supplementation. The appearance rate (%) of a meat yield more than grade A was the highest in group T1. The net profits increased by 1.2% and 13.3% in groups T1 and T2, respectively. In conclusion, if a proper feeding program (including feed safety) can be ensured, spent mushroom substrates of Flammulina velutipes can prove to be a highly profitable feed source for Hanwoo steers.

Characteristics of Low Density Fiberboards Bonded with Different Adhesives for Thermal Insulation (II) - Formaldehyde·Total Volatile Organic Compounds Emission Properties and Combustion Shapes - (다양한 접착제로 제조한 단열재용 저밀도섬유판의 특성(II) - 폼알데하이드·총휘발성유기화합물 방출 특성 및 연소 형상 -)

  • Jang, Jae-Hyuk;Lee, Min;Kang, Eun-Chang;Lee, Sang-Min
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.5
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    • pp.580-587
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    • 2017
  • Woodfiber insulation board can be considered as a one of the key material for low energy consumption, comfortable and safety construction of residential space because of its eco-friendly and high thermal insulation performance. This study was carried out to investigate the formaldehyde (HCHO) total volatile organic compounds (TVOC) emission properties and combustion shapes by flame test of low density fiberboards (LDFs) prepared with different adhesives. HCHO TVOC emission and combustion properties of LDFs prepared by melamine urea formaldehyde (MUF), phenol formaldehyde (PF), emulsified methylene diphenyl diisocyanate (eMDI) and latex resin adhesives were measured by desiccator method, 20 L chamber method, and flame test, respectively. As results, LDFs manufactured by MUF, eMDI and latex resin adhesives satisfied the Super $E_0$ grade of HCHO emission performance except PF resin. Furthermore, TVOC emission of all LDFs were satisfied the Korean indoor air quality standard (below $400{\mu}g/m^2{\cdot}h$). Especially, LDF with eMDI resin adhesive showed the lowest HCHO and TVOC emissivity, that $0.14mg/{\ell}$, $12{\mu}g/m^2{\cdot}h$, respectively. However, eMDI emitted the small amount ($3{\mu}g/m^2{\cdot}h$) of toluene in VOC components. In the flame test, LDF with MUF resin adhesives showed the most favorable shape after flame test compare to LDFs prepared other adhesives. Based on HCHO and TVOC emission, and combustion shapes, MUF resin adhesive may be recommended to prepare LDF for insulation purpose.