• Title/Summary/Keyword: Distribution safety

Search Result 3,042, Processing Time 0.037 seconds

A Study of Long-term Trends of SST in the Korean Seas by Reconstructing Historical Oceanic Data (과거 해양자료 복원을 통한 한반도 주변해역 표층수온의 장기변동 연구)

  • Park, Myung-Hee;Song, Ji-Young;Han, In-Seong;Lee, Joon-Soo
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.25 no.7
    • /
    • pp.881-897
    • /
    • 2019
  • We reconstructed and digitized the National Institute of Fisheries Science (NIFS) Serial Oceanographic observations (NSO) and Coastal Oceanographic observations (NCO) data attained prior to 1961 through historical oceanographic observation data rescue projects. Increasing trends of long-term sea surface temperature (SST) were shown from the NSO data of 21 available stations for the past 80 to 92 years. In general agreement with previous research results used in the data of the past 50 years, we calculated the rate of temperature rise. As a result of analyzing the spatial distribution of SST change rate in the Korean of shore region using selected oceanographic data, the West Sea and South Sea showed a higher tendency of temperature rise in the offshore area than in the coastal area. However, unlike the results of previous studies, the East Sea (Gangwon Line and Ulsan Line) showed a lower water temperature rise than the coastal stations. Annual fluctuations of NCO's SST data from 1989 to 1998 for three stations representing the East Sea, South Sea, and West Sea, (Jumunjin, Geomundo and Budo, respectively) revealed that the East Sea showed the highest SST increase for the 10 years. The increases were 1.63 ℃ at Jumunjin, 1.16 ℃ at Geomundo, and 0.79 ℃ at Budo. As a result of the investigation, it can be concluded that SST is repeatedly rising and falling with a period of 3 ~ 6 years. Especially, since the 1980s, most of the stations show positive anomalies of SST. Lastly, to understand ocean_atmosphere interactions, we analyzed the correlations between SST of the NCO stations and air temperature around them and the results were 0.76 for the South Sea (Geomundo), 0.34 for the West Sea (Budo), and 0.32 for the East Sea (Jumunjin) with the highest correlation in the South Sea.

PST Member Behavior Analysis Based on Three-Dimensional Finite Element Analysis According to Load Combination and Thickness of Grouting Layer (하중조합과 충전층 두께에 따른 3차원 유한요소 해석에 의한 PST 부재의 거동 분석)

  • Seo, Hyun-Su;Kim, Jin-Sup;Kwon, Min-Ho
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.22 no.6
    • /
    • pp.53-62
    • /
    • 2018
  • Follofwing the accelerating speed-up of trains and rising demand for large-volume transfer capacity, not only in Korea, but also around the world, track structures for trains have been improving consistently. Precast concrete slab track (PST), a concrete structure track, was developed as a system that can fulfil new safety and economic requirements for railroad traffic. The purpose of this study is to provide the information required for the development and design of the system in the future, by analyzing the behavior of each structural member of the PST system. The stress distribution result for different combinations of appropriate loads according to the KRL-2012 train load and KRC code was analyzed by conducting a three-dimensional finite element analysis, while the result for different thicknesses of the grouting layer is also presented. Among the structural members, the largest stress took place on the grouting layer. The stress changed sensitively following the thickness and the combination of loads. When compared with a case of applying only a vertical KRL-2012 load, the stress increased by 3.3 times and 14.1 times on a concrete panel and HSB, respectively, from the starting load and temperature load. When the thickness of the grouting layer increased from 20 mm to 80 mm, the stress generated on the concrete panel decreased by 4%, while the stress increased by 24% on the grouting layer. As for the cracking condition, tension cracking was caused locally on the grouting layer. Such a result indicates that more attention should be paid to the flexure and tension behavior from horizontal loads rather than from vertical loads when developing PST systems. In addition, the safety of each structural member must be ensured by maintaining the thickness of the grouting layer at 40 mm or more.

Monitoring of Sulfur Dioxide, Carotenoid Contents and Bacillus cereus Contamination of Dried Sweet Potato in Circulating Dried Agricultural Products (국내 유통 건조 농산물 중 고구마 말랭이의 이산화황, 카로티노이드 함량 및 바실러스 세레우스오염 정도 조사)

  • Lee, Hyeon Min;Park, Hyun Ji;Kim, Ji Na;Shin, Weon Sun;Kim, Eun Mi
    • Journal of Food Hygiene and Safety
    • /
    • v.32 no.6
    • /
    • pp.477-484
    • /
    • 2017
  • This study was conducted to investigate the content of sulfur dioxide, carotenoids and the degree of contamination of Bacillus cereus in 33 kinds of dried sweet potato from domestic mainly dried agricultural products in Korea. According to the characteristics of dried sweet potato samples, it was classified into four clusters and as a result of analyzing the contents of sulfur dioxide, carotenoids and the degree of contamination B. cereus was no significant difference among the clusters. The detection ranges of residual sulfur dioxide from 33 dried sweet potatoes ranged from 0.38 to 28.16 mg/kg, three cases (9.09%) were detected at the reference level of 10 mg/kg or more. But no samples exceeding 30 mg/kg, the tolerance level of sulfur dioxide in dried sweet potatoes were detected. Since dried sweet potato does not have a standard for carotenoids, when comparing the national and international standards of carotenoids, the range of detection of carotenoids in dried sweet potato was $46{\sim}2,663{\mu}g$/100 g, which was within the reference range of $0{\sim}9,826{\mu}g$/100 g. In principle colonies suspected to be B. cereus in dried sweet potato were not detected. In 7 cases (21.21%), there were detected in the range of 0.05~1.59 log CFU/g but not more than 3 log CFU/g as the reference value. The results of this study are expected to be used as basic data to establish quality standard for dried sweet potatoes. In order to control the quality of dried sweet potatoes in domestic market, raw materials, drying method and packaging after distribution, it is necessary to maintain and maintain the process steadily.

Investigation of the Lactic Acid Bacteria Content of Probiotic and Lactic Acid Bacteria Products: a Study on Changes in the Preservation Method of Probiotic Products (프로바이오틱스와 유산균 제품의 균수 함량과 보존방법에 따른 변화 연구)

  • Kim, Young-Su;Hwang, Sun-Il;Kim, Sang-Tae;Han, Na-Eun;Kim, Hye-Young;Kim, Hyun-Soo;Park, Kwang-Hee;Yoon, Mi-Hye
    • Journal of Food Hygiene and Safety
    • /
    • v.33 no.6
    • /
    • pp.474-482
    • /
    • 2018
  • The aim of this study was to determine and analyze probiotic contents, pH, and acidity of 120 samples of health functional and processed foods containing lactic acid bacteria distributed in 2017. The changes due to the preservation methods were also determined and analyzed in five probiotic products. Two samples of the 85 health functional food products had lactic acid bacteria at lower levels than the marked amount required to meet Korean food standards, whereas the 35 processed products were all suitable for distribution. The averages for probiotic contents, pH, and acidity were $1.2{\times}10^{10}CFU/g$, 5.35, and 1.29%, respectively. The average count of lactic acid bacteria in the 17 samples with marked amount among the 35 processed foods was $5.8{\times}10^8CFU/g$. The effects of preservation temperature ($-20^{\circ}C$, $4^{\circ}C$, $20^{\circ}C$, and $40^{\circ}C$) and storage period (1, 3, and 6 months) on probiotic content, pH, and acidity were determined for 5 probiotic products. After 1 to 6 months, the average reduction in probiotic content was by 59%; the lowest reduction occurred at $4^{\circ}C$ and the highest reduction occurred at $40^{\circ}C$. In addition, 3 of the 5 products showed a rapid decrease in probiotic content by more than 70% at $40^{\circ}C$ after a storage period of 1 to 3 months. Therefore, from this study results, it is recommended that products containing lactic acid bacteria should be refrigerated and consumed shortly after purchase.

Anti-listeria Activity of Lactococcus lactis Strains Isolated from Kimchi and Characteristics of Partially Purified Bacteriocins (김치에서 분리한 Lactococcus lactis 균주의 항리스테리아 활성 및 부분 정제된 박테리오신의 특성)

  • Son, Na-Yeon;Kim, Tae-Woon;Yuk, Hyun-Gyun
    • Journal of Food Hygiene and Safety
    • /
    • v.37 no.2
    • /
    • pp.97-106
    • /
    • 2022
  • Listeria monocytogenes (L. monocytogenes) is one of gram-positive foodborne pathogens with a very high fatality rate. Unlike most foodborne pathogens, L. monocytogenes is capable of growing at low temperatures, such as in refrigerated foods. Thus, various physical and chemical prevention methods are used in the manufacturing, processing and distribution of food. However, there are limitations to the methods such as possible changes to the food quality and the consumer awareness of synthetic preservatives. Thus, the aim of this study was to evaluate the anti-listeria activity of lactic acid bacteria (LAB) isolated from kimchi and characterize the bacteriocin produced by Lactococcuslactis which is one of isolated strains from kimchi. The analysis on the anti-listeria activity of a total of 36 species (Lactobacillus, Weissella, Lactobacillus, and Lactococcus) isolated from kimchi by the agar overlay method revealed that L. lactis NJ 1-10 and NJ 1-16 had the highest anti-listeria activity. For quantitatively analysis on the anti-listeria activity, NJ 1-10 and NJ 1-16 were co-cultured with L. monocytogenes in Brain Heat Infusion (BHI) broth, respectively. As a result, L. monocytogenes was reduced by 3.0 log CFU/mL in 20 h, lowering the number of bacteria to below the detection limit. Both LAB strains showed anti-listeria activity against 24 serotypes of L. monocytogenes, although the sizes of clear zone was slightly different. No clear zone was observed when the supernatants of both LAB cultures were treated with proteinase-K, indicating that their anti-listerial activities might be due to the production of bacteriocins. Heat stability of the partially purified bacteriocins of NJ 1-10 and NJ 1-16 was relatively stable at 60℃ and 80℃. Yet, their anti-listeria activities were completely lost by 60 min of treatment at 100℃ and 15 min of treatment at 121℃. The analysis on the pH stability showed that their anti-listeria activities were the most stable at pH 4.01, and decreased with the increasing pH value, yet, was not completely lost. Partially purified bacteriocins showed relatively stable anti-listeria activities in acetone, ethanol, and methanol, but their activities were reduced after chloroform treatment, yet was not completely lost. Conclusively, this study revealed that the bacteriocins produced by NJ 1-10 and NJ 1-16 effectively reduced L. monocytogenes, and that they were relatively stable against heat, pH, and organic solvents, therefore implying their potential as a natural antibacterial substance for controlling L. monocytogenes in food.

Biological Toxicity Assessment of Sediment at an Ocean Dumping Site in Korea (폐기물 배출해역 퇴적물의 생물학적 독성평가 연구)

  • Seok, Hyeong Ju;Kim, Young Ryun;Kim, Tae Won;Hwang, Choul-Hee;Son, Min Ho;Choi, Ki-young;Kim, Chang-joon
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.28 no.1
    • /
    • pp.1-9
    • /
    • 2022
  • The effect of sediments in a waste dumping area on marine organisms was evaluated using sediment toxicity tests with a benthic amphipod (Monocorophium acherusicum) and bioluminescent bacterium (Vibrio fischeri) in accordance with the Korean Standard Method for Marine Wastes (KSMMW). Nine sites in the East Sea-Byeong, East Sea-Jeong, and Yellow Sea-Byeong areas were sampled from 2016 to 2019. The test results showed that the relative average survival rate (benthic amphipods) and relative luminescence inhibition rate (luminescent bacteria) were below 30%, which were judged to be "non-toxic." However, in the t-test, a total of 12 benthic amphipod samples (6, 1, 1, and 4 in 2016, 2017, 2018, and 2019, respectively) were significantly different (p<0.05) from the control samples. To identify the source of toxicity on benthic amphipods, a simple linear regression analysis was performed between the levels of eight heavy metals (Cr, As, Ni, Cd, Cu, Pb, Zn, and Hg) in sediments and the relative average survival rate. The results indicated that Cr had the highest contribution to the toxicity of benthic amphipods (p = 0.000, R2 = 0.355). In addition, Cr was detected at the highest concentration at the DB-85 station and exceeded the Marine Environment Standards every year. Although the sediments were determined as "not toxic" according to the ecotoxicity criteria of the KSMMW, the results of the statistical significance tests and toxicity identification evaluation indicated that the toxic effect was not acceptable. Therefore, revising the criteria for determining the toxic effect by deriving a reference value through quantitative risk assessment using species sensitivity distribution curves is necessary in the future.

Characteristics of Marine Algal Communities in Village Fishing Grounds Near Large Wildfires in Uljin-gun (울진군 대형산불 발생 인근 마을어장의 해조류 군집 특성)

  • Jeong Hee Shim;Hee Chan Choi;Hae-Kun Jung;Jong-Ku Gal;Jeong-Min Shim;Sung-Eic Hong;Chul-Hui Kwoun;Sang-Woo Kim
    • Journal of the Korean Society of Marine Environment & Safety
    • /
    • v.29 no.2
    • /
    • pp.87-97
    • /
    • 2023
  • In this study, we examined the effects of a large wildfire in the coastal area of Uljin-gun. The analysis of water quality and the dominant species, species composition, and community structure of marine algal was conducted quarterly in 2022 at Nagok (F-1), Hujeong (F-2), Bongpyeong (F-3), and Gongse Port (F-C) in Uljin-gun. As a result of water quality analysis, the pH, a factor of wildfire impact was 8.07~8.30 and 8.12~8.48 in surface and bottom layers, respectively, which are normal values in coastal waters of the East Sea, suggesting no direct impact from wildfires. By marine algal species composition, the coastal areas show the following order: Rhodophyta (58.1%) > Ochrophyta (25.8%) > Chlorophyta (14.5%) > Magnoliophyta (1.6%). By season, Undaria pinnatifida was the most dominant at Nagok and Hujeong in March and June, which in September and November, Gelidium elegans and Lithophyllum sp. were the most dominant in Bongpyeong and Gongse Port, respectively. In the cluster analysis, the stations were divided into two groups according to presence and absence of specific marine algal by season. The dominant species were U. pinnatifida, G. elegans and D. divaricata in group A, and Lithophyllum sp. was mainly present in group B. Thus, the species composition and group structure reflected the normal seasonal change pattern with water temperature variation and showed little significant difference from the control site, suggesting no direct effects of the wildfire on algae distribution in Uljin.

Heavy concrete shielding properties for carbon therapy

  • Jin-Long Wang;Jiade J Lu;Da-Jun Ding;Wen-Hua Jiang;Ya-Dong Li;Rui Qiu;Hui Zhang;Xiao-Zhong Wang;Huo-Sheng Ruan;Yan-Bing Teng;Xiao-Guang Wu;Yun Zheng;Zi-Hao Zhao;Kai-Zhong Liao;Huan-Cheng Mai;Xiao-Dong Wang;Ke Peng;Wei Wang;Zhan Tang;Zhao-Yan Yu;Zhen Wu;Hong-Hu Song;Shuo-Yang Wei;Sen-Lin Mao;Jun Xu;Jing Tao;Min-Qiang Zhang;Xi-Qiang Xue;Ming Wang
    • Nuclear Engineering and Technology
    • /
    • v.55 no.6
    • /
    • pp.2335-2347
    • /
    • 2023
  • As medical facilities are usually built at urban areas, special concrete aggregates and evaluation methods are needed to optimize the design of concrete walls by balancing density, thickness, material composition, cost, and other factors. Carbon treatment rooms require a high radiation shielding requirement, as the neutron yield from carbon therapy is much higher than the neutron yield of protons. In this case study, the maximum carbon energy is 430 MeV/u and the maximum current is 0.27 nA from a hybrid particle therapy system. Hospital or facility construction should consider this requirement to design a special heavy concrete. In this work, magnetite is adopted as the major aggregate. Density is determined mainly by the major aggregate content of magnetite, and a heavy concrete test block was constructed for structural tests. The compressive strength is 35.7 MPa. The density ranges from 3.65 g/cm3 to 4.14 g/cm3, and the iron mass content ranges from 53.78% to 60.38% from the 12 cored sample measurements. It was found that there is a linear relationship between density and iron content, and mixing impurities should be the major reason leading to the nonuniform element and density distribution. The effect of this nonuniformity on radiation shielding properties for a carbon treatment room is investigated by three groups of Monte Carlo simulations. Higher density dominates to reduce shielding thickness. However, a higher content of high-Z elements will weaken the shielding strength, especially at a lower dose rate threshold and vice versa. The weakened side effect of a high iron content on the shielding property is obvious at 2.5 µSv=h. Therefore, we should not blindly pursue high Z content in engineering. If the thickness is constrained to 2 m, then the density can be reduced to 3.3 g/cm3, which will save cost by reducing the magnetite composition with 50.44% iron content. If a higher density of 3.9 g/cm3 with 57.65% iron content is selected for construction, then the thickness of the wall can be reduced to 174.2 cm, which will save space for equipment installation.

Antimicrobial Resistance and Genetic Characterization of Pathogenic Campylobacter spp. Isolated from Distribution Poultry in Gwangju Metropolitan City (광주지역 유통 가금육에서 분리된 캠필로박터균의 유전적 특성 및 항생제 내성)

  • Min Gyou Lee;Hye Jin Jeong;Se mi Lee;Hyang Hee Lee;Eun Jin Seo;Jung Hee Park;Geu Ne Oh;Si Eun Seo;Jung Mi Seo;Ae Gyeong Kim
    • Journal of Food Hygiene and Safety
    • /
    • v.39 no.1
    • /
    • pp.16-25
    • /
    • 2024
  • This study investigated the prevalence of Campylobacter spp. In poultry meat and its association with foodborne illnesses in Gwangju, South Korea. It was found that out of the 307 samples of poultry meat examined, 111 (36.2%) were infected with Campylobacter spp. Among the isolated strains, 102 were identified as Campylobacter jejuni and 14 as Campylobacter coli. The detection rate of Campylobacter spp. was higher in duck meat (63.1%) than in chicken meat (26.0%). In 5 samples (1 chicken, 4 duck), both Campylobacter jejuni and Campylobacter coli were found together. The antimicrobial resistance test showed that 99 strains were resistant to more than one antimicrobial. The most common antimicrobial resistance was seen against ciprofloxacin (84.5%), followed by nalidixic acid (82.8%), tetracycline (44.0%), and gentamicin (2.6%). The isolated Campylobacter spp. were serotyped and the results showed the presence of HS2 (20 strains), HS15 (11 strains), HS19 (9 strains), and HS8 (8 strains). Considering the findings, it is recommended to maintain hygienic practices during the cooking process and to take necessary precautions to prevent the spread of pathogenic bacteria.

Determination of Cost and Measurement of nursing Care Hours for Hospice Patients Hospitalized in one University Hospital (일 대학병원 호스피스 병동 입원 환자의 간호활동시간 측정과 원가산정)

  • Kim, Kyeong-Uoon
    • Journal of Korean Academy of Nursing Administration
    • /
    • v.6 no.3
    • /
    • pp.389-404
    • /
    • 2000
  • This study was designed to determine the cost and measurement of nursing care hours for hospice patients hostpitalized in one university hospital. 314 inpatients in the hospice unit 11 nursing manpower were enrolled. Study was taken place in C University Hospital from 8th to 28th, Nov, 1999. Researcher and investigator did pilot study for selecting compatible hospice patient classification indicators. After modifying patient classification indicators and nursing care details for general ward, approved of content validity by specialist. Using hospice patient classification indicators and per 5 min continuing observation method, researcher and investigator recorded direct nursing care hours, indirect nursing care hours, and personnel time on hospice nursing care hours, and personnel time on hospice nursing care activities sheet. All of the patients were classified into Class I(mildly ill), Class II (moderately ill), Class III (acutely ill), and Class IV (critically ill) by patient classification system (PCS) which had been carefully developed to be suitable for the Korean hospice ward. And then the elements of the nursing care cost was investigated. Based on the data from an accounting section (Riccolo, 1988), nursing care hours per patient per day in each class and nursing care cost per patient per hour were multiplied. And then the mean of the nursing care cost per patient per day in each class was calculated. Using SAS, The number of patients in class and nursing activities in duty for nursing care hours were calculated the percent, the mean, the standard deviation respectively. According to the ANOVA and the $Scheff{\'{e}$ test, direct nursing care hours per patient per day for the each class were analyzed. The results of this study were summarized as follows : 1. Distribution of patient class : class IN(33.5%) was the largest class the rest were class II(26.1%) class III(22.6%), class I(17.8%). Nursing care requirements of the inpatients in hospice ward were greater than that of the inpatients in general ward. 2. Direct nursing care activities : Measurement ${\cdot}$ observation 41.7%, medication 16.6%, exercise ${\cdot}$ safety 12.5%, education ${\cdot}$ communication 7.2% etc. The mean hours of direct nursing care per patient per day per duty were needed ; 69.3 min for day duty, 64.7 min for evening duty, 88.2 min for night duty, 38.7 min for shift duty. The mean hours of direct nursing care of night duty was longer than that of the other duty. Direct nursing care hours per patient per day in each class were needed ; 3.1 hrs for class I, 3.9 hrs for class II, 4.7 hrs for class III, and 5.2 hrs for class IV. The mean hours of direct nursing care per patient per day without the PCS was 4.1 hours. The mean hours of direct nursing care per patient per day in class was increased significantly according to increasing nursing care requirements of the inpatients(F=49.04, p=.0001). The each class was significantly different(p<0.05). The mean hours of direct nursing care of several direct nursing care activities in each class were increased according to increasing nursing care requirements of the inpatients(p<0.05) ; class III and class IV for medication and education ${\cdot}$ communication, class I, class III and class IV for measurement ${\cdot}$ observation, class I, class II and class IV for elimination ${\cdot}$ irrigation, all of class for exercise ${\cdot}$ safety. 3. Indirect nursing care activities and personnel time : Recognization 24.2%, house keeping activity 22.7%, charting 17.2%, personnel time 11.8% etc. The mean hours of indirect nursing care and personnel time per nursing manpower was 4.7 hrs. The mean hours of indirect nursing care and personnel time per duty were 294.8 min for day duty, 212.3 min for evening duty, 387.9 min for night duty, 143.3 min for shift duty. The mean of indirect nursing care hours and personnel time of night duty was longer than that of the other duty. 4. The mean hours of indirect nursing care and personnel time per patient per day was 2.5 hrs. 5. The mean hours of nursing care per patient per day in each class were class I 5.6 hrs, class II 6.4 hrs, class III 7.2 hrs, class IV 7.7 hrs. 6. The elements of the nursing care cost were composed of 2,212 won for direct nursing care cost, 267 won for direct material cost and 307 won for indirect cost. Sum of the elements of the nursing care cost was 2,786 won. 7. The mean cost of the nursing care per patient per day in each class were 15,601.6 won for class I, 17,830.4 won for class II, 20,259.2 won for class III, 21,452.2 won for class IV. As above, using modified hospice patient classification indicators and nursing care activity details, many critical ill patients were hospitalized in the hospice unit and it reflected that the more nursing care requirements of the patients, the more direct nursing care hours. Emotional ${\cdot}$ spiritual care, pain ${\cdot}$ symptom control, terminal care, education ${\cdot}$ communication, narcotics management and delivery, attending funeral ceremony, the major nursing care activities, were also the independent hospice service. But it is not compensated by the present medical insurance system. Exercise ${\cdot}$ safety, elimination ${\cdot}$ irrigation needed more nursing care hours as equal to that of intensive care units. The present nursing management fee in the medical insurance system compensated only a part of nursing car service in hospice unit, which rewarded lower cost that that of nursing care.

  • PDF