• Title/Summary/Keyword: HR Data

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Tumor Habitat Analysis Using Longitudinal Physiological MRI to Predict Tumor Recurrence After Stereotactic Radiosurgery for Brain Metastasis

  • Da Hyun Lee;Ji Eun Park;NakYoung Kim;Seo Young Park;Young-Hoon Kim;Young Hyun Cho;Jeong Hoon Kim;Ho Sung Kim
    • Korean Journal of Radiology
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    • v.24 no.3
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    • pp.235-246
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    • 2023
  • Objective: It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. Materials and Methods: Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27-82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrast-enhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. Results: The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46-4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01-2.35; P = 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). Conclusion: After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

The Design and Implementation of GSA(Grid System Account) for an Effective Analyzation of Enterprise Grid Computing system (Enterprise Grid Computing 시스템의 효율적 분석을 위한 GSA 시스템의 설계와 구현)

  • Chung, Moon-Ki
    • Proceedings of the Korea Information Processing Society Conference
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    • 2007.05a
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    • pp.540-543
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    • 2007
  • 최근의 그리드 컴퓨팅 시스템 환경은 단일 환경에서 작게는 2~4CPU, 많게는 수백 CPU 이상의 시스템으로 구축되고 있고, 더욱이 지역적으로도 멀리 떨어져 있다. 따라서 이를 운용하는 기업에서는 시스템의 사용 현황을 신속하게 분석할 필요가 있다. 그러나 이렇게 혼재된 이 기종 및 컴퓨팅 환경하에서의 각 지역별 시스템 사용현황을 효과적으로 분석 한다는 것은 매우 어려운 일이다. 기존에 사용되어 온 그리드 컴퓨팅 시스템 환경에서의 사용율 관리 방법들은 Queueing 시스템이 가지고 있는 Accounting 분석 명령어로 text 형태의 Accounting raw data 의 결과를 추출하여 가공 처리하므로 데이터 증가 시 반응 속도가 현격하게 느려지는 상황이 발생한다. 또한 원격지 그리드 컴퓨팅 시스템 군의 사용율 분석은 데이터 분석 시 매번 원격지접근 절차를 사용하여 그리드 컴퓨팅 시스템 군에 접근한 후 해당 로컬 시스템 분석을 해야 하고 각 원격지시스템군별로 추출 된 데이터를 통합 관리해야 하는 문제점을 가지고 있다. 따라서 이러한 문제점을 해결하고자 하는 것이 본 논문에서 제안하는 3-tier 구조의 GSA(Grid System Account)이다. 제안한 GSA 는 각 원격지 별 데이터를 객체화하여 Database 에 저장 함으로써 데이터 분석 시 효과적으로 처리할 수 있으며, 다수의 원격지 그리드 컴퓨팅 시스템 군에 대한 복합적인 분석이 필요할 때 효율적으로 대처할 수 있다. 본 논문에서는 GSA 의 설계방법을 제안하고 구현하여 실 성능을 시험함으로써 보다 효율적인 그리드 컴퓨팅 시스템의 사용율 분석 관리가 가능함을 보였다.포는 감수성을 보이지 않았다. 따라서 위의 결과로부터 SLT-I에 감수성을 보이지 않은 Raw264.7세포를 대상으로 Gb3 발현 정도와 SLT-I의 세포독성의 관계를 규명하고자 Gb3의 발현을 증가시킨 후 SLT-I의 세포독성을 재차 평가하였다. 이 결과 $TNF-{\alpha}$의 처리에 의하여 6 hrs에 Gb3의 발현이 정점(43.5%)에 이르렀으며 36 hrs에 정상 수준(25.0%)으로 환원되었다. 그러나, Gb3의 발현이 증가함에도 불구하고 SLT-I의 세포독성에는 변화가 관찰되지 않았다. 따라서, SLT-I에 의한 세포독성은 세포의 종류에 따라서 다르며 또한, Gb3의 발현정도에만 의존적이지는 않을 것으로 생각된다. 이와 같은 결과는 E. coli 0157의 감염증 병인 연구에 있어 SLT-I과 Gb3의 발현의 상관관계에 대한 보다 심도 있는 연구가 필요함을 시사한다.만 분할률, 배반포 형성률 및 배반포의 세포수를 증가시키는 것으로 사료된다.수의 유출입 지점에 온도센서를 부착하여 냉각수의 온도를 측정하고 냉각수의 공급량과 대기의 온도 등을 측정하여 대사열의 발생을 추정할 수 있었다. 동시에 이를 이용하여 유가배양시 기질을 공급하는 공정변수로 사용하였다 [8]. 생물학적인 폐수처리장치인 활성 슬러지법에서 미생물의 활성을 측정하는 방법은 아직 그다지 개발되어있지 않다. 본 연구에서는 슬러지의 주 구성원이 미생물인 점에 착안하여 침전시 슬러지층과 상등액의 온도차를 측정하여 대사열량의 발생량을 측정하고 슬러지의 활성을 측정할 수 있는 방법을 개발하였다.enin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이

Effects of Hwangryunhaedok-Tang and Geongangbuja-Tang on the Change of Interleukin-6 and $TNF-{\alpha}$ Level Induced by LPS I.C.V. Injection in Mice (황연해독탕(黃連解毒湯)과 건강부자탕(乾薑附子湯)이 LPS유도에 의한 마우스 혈중 IL-6와 $TNF-{\alpha}$ 변화에 미치는 영향)

  • Park, Su-Hyun;Kwon, Yong-Uk;Lee, Tae-Hee
    • Herbal Formula Science
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    • v.15 no.1
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    • pp.185-197
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    • 2007
  • Objective : This study was conducted to investigate the effects of Hwangryunhaedok-Tang and Geongangbuja-Tang on the change of interleukin-6 (IL-6) and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$) level induced by LPS I.C.V. injection in mice. Method : We devided group into 6 mice and 6 mice were assingned to each group. In the normal group only saline was administered intragastrically, and in the control group LPS was injected intracerebroventricularly 1 hr after intragastric administration of saline. In the experiment groups Hwangryunhaedok-Tang(0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS(100mg/mouse) I.C.V. injection.. Also Geongangbuja-Tang (0.5g/kg, 1.0g/kg, 3.0g/kg) was administered intragastrically to mice 1 hr prior to LPS(100mg/mouse) I.C.V. injection. To measure the plasma IL-6 and $TNF-{\alpha}$ level of mice, their blood samples were collected from retro-orbital plexus, immediately centrifuged at $4^{\circ}C$, and plasma was removed and stored frozen at $-83^{\circ}C$ for later determination of IL-6 and $TNF-{\alpha}$. The level of IL-6 and $TNF-{\alpha}$ production was measured by enzyme-linked immunosorbent assay in the plasma. Result : Regarding IL-6 level, The 0.5g/kg and the 1g/kg groups of Geongangbuja-Tang decreased IL-6 level. Especially the 3g/kg control group decreased IL-6 level significantly than the normal group(p<0.01). Regarding $TNF-{\alpha}$ level, the 3g/kg group of Geongangbuja-Tang decreased it significantly(p<0.05). Conclusion : These data revealed that Hwangryunhaedok-Tang might not have the anti imflammatory effect and Geongangbuja-Tang(3g/kg)might have the anti imflammatory effect by reducing the plasma IL-6 and $TNF-{\alpha}$ level in mice LPS Injection.EIM (Eighteen Incompatible Medicaments) is an important component in Oriental pharmacology and is directly related to clinical prescriptions. Medical practitioners argued that the definite cause and meaning of EIM was ambiguous and therefore debated the issue of clinical application of the EIM. This study conducted an in-depth literary research on the origin, meaning and contents of EIM with the purpose to contribute in its efforts to be used clinically. Even after thousands of years have past since establishment of Oriental medicine, EIM is still tabooed and was an obstacle that hindered ideologies. Modern herbal medicine texts claim that the use of EIM can reduce treatment effects and promote poisoning and side effects. However, since long ago, there has been medical practitioners who reject this as false. Recently, poisoning caused by EIM has been claimed to be from the toxicity of the drug itself, rather than the result of interaction between the drugs, and therefore they suggest that EIM is not a forbidden domain. In addition, EIM showed a difference in number depending on the era. However, this can be understood not as a definite number, but instead as a warning to be careful during combination of drugs for use as clinical medicine. Historically, there were very few cases in which EIM was used for clinical tests and thus, the clinical value is not, while others applied EIM directly to their bodies, which showed signs for the usefulness and potential of EIM for us. A more concrete and in-depth study must be made on EIM.

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OECD High Production Volume Chemicals Program: Ecological Risk Assessment of Copper Cyanide (대량생산화학물질 초기위해성평가: 시안화구리의 초기 생태위해성평가)

  • Baek, Yong-Wook;Kim, Eun-Ju;Yoo, Sun-Kyoung;Ro, Hee-Young;Kim, Hyun-Mi;Eom, Ig-Chun;Kim, Pil-Je
    • Korean Journal of Ecology and Environment
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    • v.44 no.3
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    • pp.272-279
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    • 2011
  • Copper cyanide is a chemical produced in large quantities with 2,500 tonnes being produced in 2006. It is mainly used for electroplating copper, particularly alkali-Cu plate and brass plating. The purpose of this study is to reassess the physicochemical properties and environmental fate of copper cyanide based on reliable data and and to conduct an ecotoxicity test according to the OECD test guidelines as an initial environmental risk assessment (need to state where this was done). Metal containing inorganic substances are not subject to degradation, biodegradation or hydrolysis. Aquatic toxicity tests of copper cyanide were conducted according to OECD test guideline 201, 202 and 203 for green algae, daphnia, and fish, respectively. The following acute toxicity test results were obtained for aquatic species: 0.089 mg $L^{-1}$ (Algae, 72 Hr-$EC_{50}$); 0.21 mg $L^{-1}$ (flea, 48 Hr-$LC_{50}$); 0.62 mg $L^{-1}$ (Fish, 96 Hr-$ErC_{50}$). The chemical possesses properties indicating a hazard for the aquatic environment (acute toxicity in fish, daphnia and algae below 1.0 mg $L^{-1}$). As a result of this study, copper cyanide has become a candidate for detailed risk assessment. Countries that produce this chemical in significant quantities are recommended to perform specific assessments.

The Occurrence of Renal Scarring in Children with Unilateral Vesicoureteral Reflux (일측성 방광 요관 역류 환아에서 신반흔의 발생)

  • Lee, Tae Ho;Son, Mi Ran;Byun, Soon Ok;Moon, Jung Woong
    • Clinical and Experimental Pediatrics
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    • v.48 no.9
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    • pp.998-1003
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    • 2005
  • Purpose : We evaluated the occurrence of renal scarring in children with unilateral vesicoureteral reflux(VUR), and the relationships between renal scar formation and risk factors such as VUR, duration of fever, acute-phase reactant, age, and sex. Methods : We retrospectively analyzed the data of 35 children newly diagnosed with unilateral vesicoureteral reflux after urinary tract infection(UTI) in Wallace Memorial Baptist Hospital between January 1996 and December 2004. Ultrasonography, Erythrocyte sedimentation rate(ESR), and C-reactive protein(CRP) were performed initially. Voiding cystourethrography(VCUG) was performed 1 to 3 weeks after treatment with UTI. $^{99m}Tc$-dimercaptosuccinic acid(DMSA) scan was performed 4 to 6 months after treatment. Results : Scintigraphic renal damage was present in 29 percent of the refluxing and in 3 percent of the nonrefluxing kidneys(P<0.05). The severity of VUR was significantly correlated with renal scar formation(P<0.05). The duration of fever before treatmen($5.0{\pm}1.3$ vs $2.6{\pm}1.3$) and prolonged fever of over 5 days were significantly different between renal scar group and non-renal scar group(P<0.05). ESR($56.3{\pm}23.8$ vs $27.9{\pm}18.1mm/hr$, P<0.05) and CRP($12.8{\pm}7.3$ vs $3.9{\pm}3.8mg/dL$, P<0.05) at the diagnosis of UTI in the renal scar group were higher, compared to those of the non-renal scar group. There were no significant differences in age and sex between the two groups. Conclusion : The presence and grade of VUR, the duration of fever before treatment, prolonged fever over 5 days, ESR, and CRP were risk factors for renal scarring, irrespective of age and sex. Diagnosis and management of VUR, in children with UTI, is important to prevent renal scars.

Design and Optimization of Pilot-Scale Bunsen Process in Sulfur-Iodine (SI) Cycle for Hydrogen Production (수소 생산을 위한 Sulfur-Iodine Cycle 분젠반응의 Pilot-Scale 공정 모델 개발 및 공정 최적화)

  • Park, Junkyu;Nam, KiJeon;Heo, SungKu;Lee, Jonggyu;Lee, In-Beum;Yoo, ChangKyoo
    • Korean Chemical Engineering Research
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    • v.58 no.2
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    • pp.235-247
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    • 2020
  • Simulation study and validation on 50 L/hr pilot-scale Bunsen process was carried out in order to investigate thermodynamics parameters, suitable reactor type, separator configuration, and the optimal conditions of reactors and separation. Sulfur-Iodine is thermochemical process using iodine and sulfur compounds for producing hydrogen from decomposition of water as net reaction. Understanding in phase separation and reaction of Bunsen Process is crucial since Bunsen Process acts as an intermediate process among three reactions. Electrolyte Non-Random Two-Liquid model is implemented in simulation as thermodynamic model. The simulation results are validated with the thermodynamic parameters and the 50 L/hr pilot-scale experimental data. The SO2 conversions of PFR and CSTR were compared as varying the temperature and reactor volume in order to investigate suitable type of reactor. Impurities in H2SO4 phase and HIX phase were investigated for 3-phase separator (vapor-liquid-liquid) and two 2-phase separators (vapor-liquid & liquid-liquid) in order to select separation configuration with better performance. The process optimization on reactor and phase separator is carried out to find the operating conditions and feed conditions that can reach the maximum SO2 conversion and the minimum H2SO4 impurities in HIX phase. For reactor optimization, the maximum 98% SO2 conversion was obtained with fixed iodine and water inlet flow rate when the diameter and length of PFR reactor are 0.20 m and 7.6m. Inlet water and iodine flow rate is reduced by 17% and 22% to reach the maximum 10% SO2 conversion with fixed temperature and PFR size (diameter: 3/8", length:3 m). When temperature (121℃) and PFR size (diameter: 0.2, length:7.6 m) are applied to the feed composition optimization, inlet water and iodine flow rate is reduced by 17% and 22% to reach the maximum 10% SO2 conversion.

The Effects of Processing Methods of Corn on In vitro DM Digestability and In sacco Degradability in Rumen (옥수수 가공방법이 In vitro 건물소화율 및 In sacco 건물 분해율에 미치는 영향)

  • Son, K.N.;Kim, Y.K. Kim;Lee, S.K.;Kim, H.S.
    • Journal of Animal Science and Technology
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    • v.45 no.3
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    • pp.433-442
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    • 2003
  • The objective of these studies were to examine the effects of processing methods of corn grains on in vitro dry matter digestability and in sacco degradability in the rumen by three ruminally cannulated dry Holstein cows. The corns for these experiments were untreated; whole corn L(density; 660 g/$\ell$), whole corn H(density; 740 g/$\ell$), and treated by four different types: Ground corn, 3.8 mm, 2.8 mm, and 1.5 mm flaked corns. The results obtained were summarized as follows: The DM degradabilities, after 48 hr incubation by in sacco method, were the highest(94.4, 88.0 and 87.0%, respectively) in 1.5 mm flaked corn, ground corn, and 2.8 mm flaked corn. The 3.8 mm flaked corn was degraded significantly lower than these. Until 12 hr incubation, whole corn L tended to be degraded little more than whole corn H, was not significantly different. However, after 24 hr incubation, the significant differences between whole corn L and whole corn H were shown(P<0.05). The DM digestabilities by in vitro digestion were the highest for 1.5 mm flaked corn and ground corn(92.3 and 91.2%, respectively)(P<0.05), followed by 2.8 mm and 3.8 mm flaked corn(83.9 and 83.4%, respectively), tended to be similar to those by in sacco method. Whole corn L was digested twice more rapidly than whole corn H. Summarizing the experimental data, compared with unprocessed corns, the flaked corns were significantly increased in the degradabilities of dry matter in the rumen. In addition, as increasing the flaking degree of corn, the degradabilities of dry matter were significantly improved. Referring to these kinds of physical characteristics of grain sources in the ruminal degradabilities, it is believed to be possible to optimize the environment of the fermentation in the rumen.

Optimization of Extraction Conditions to Obtain Functional Components from Buckwheat (Fagopyrum esculentum M.) Sprouts, using Response Surface Methodology (반응표면분석법에 의한 메밀(Fagopyrum esculentum M.) 새싹 기능성분의 추출 조건 최적화)

  • Park, Kee-Jai;Lim, Jeong-Ho;Kim, Bum-Keun;Jeong, Jin-Woong;Kim, Jong-Chan;Lee, Myung-Heon;Cho, Young-Sim;Jung, Hee-Yong
    • Food Science and Preservation
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    • v.16 no.5
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    • pp.734-741
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    • 2009
  • Response surface methodology (RSM) was used to optimize extraction conditions for functional components of buckwheat (Fagopyrum esculentum). A central composite design was applied to investigate the effects of three independent variables, namelyextraction temperature (X1), extraction time (X2), and ethanol concentration (X3), on responses including extraction yield (Y1), total phenolic content in the extract (Y2), $\alpha$-glucosidase inhibition activity (Y3), and acetylcholine esterase (ACE) inhibition activity (Y4). Data were analyzed using an expert design strategy and statistical software. The maximum yield was 24.95% (w/w) at $55.75^{\circ}C$ extraction temperature, 8.75 hextraction time, and 15.65% (v/v) ethanol. The maximum total phenolic yield was 222.45 mg/100 g under the conditions of $28.11^{\circ}C$ extraction temperature, 8.65 h extraction time, and 81.72% (v/v) ethanol. The maximum $\alpha$-glucosidase inhibition activity was 85.38% at $9.62^{\circ}C$, 7.86 h, and 57.58% (v/v) ethanol. The maximum ACE inhibition activity was 86.91% under extraction conditions of $10.12^{\circ}C$, 4.86 h, and 44.44% (v/v) ethanol. Based on superimposition of a four-dimensional RSM with respect to levels of total phenolics, $\alpha$-glucosidase inhibition activity, and ACE inhibition activity, obtained under various extraction conditions, the optimum ranges of conditions were an extraction temperature of $0-70^{\circ}C$, an extraction time of 2-8 h, and an ethanol concentration of 30-80% (v/v).

Influence of Accumulated Hours of Low Temperature in Dormant and Changing Temperature after Bud Breaking on Flowering of Main Apple Cultivars in Korea (휴면기 저온 누적 시간 및 발아 후 변온이 국내 주요 사과품종의 개화에 미치는 영향)

  • Kweon, Hun-Joong;Park, Moo-Yong;Song, Yang-Yik;Sagong, Dong-Hoon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.19 no.4
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    • pp.252-269
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    • 2017
  • This study was carried out to examine the base temperature to flowering and the average days to flowering by accumulated hours of low temperature ($5.0^{\circ}C$) or changing temperature after bud breaking. Over-all, the prediction of flowering time in the commercial apple cultivars ('Fuji' and 'Tsugaru') and apple cultivars ('Chukwang', 'Gamhong', 'Hongan', 'Honggeum', 'Hongro', 'Hongso', 'Hwahong', 'Summer dream', 'Sunhong') bred in Korea at the Gunwi region for 4 years (from 2009 to 2012) was investigated. Also, this study estimated the flowering time when the air temperature of Gunwi region rises at $5.0^{\circ}C$ was investigated using the same data. The range of accumulated hours of low temperature (chilling requirement) was from 0 hour to 1,671 hours, and the range of high temperature (heat requirements) to flowering after low temperature treatment was from $5.0^{\circ}C$ to $29.0^{\circ}C$. The treatments of changing temperature after bud breaking were classified as constant temperature treatment (control) and $5.0{\sim}10.0^{\circ}C$ elevation or descent treatments. The results show that the average days to flowering was longer with shorter accumulated hours of low temperature, and the average days from bud breaking to flowering of 0 hour treatment was longer about 2~4 weeks than that of 1,335~1,503 hours treatments. In comparing to apple cultivars, the all cultivars were not flowered under $10.0^{\circ}C$ after bud breaking, and the cultivars with low chilling requirements needed low heat requirements for flowering. The average days to flowering of treatments that the air temperature after bud breaking was controlled about $15.0^{\circ}C$ was shorter about 1~3 weeks than that of treatments was controlled about $10.0^{\circ}C$. In the treatment of changing temperature after bud breaking, the average days from bud breaking to flowering of temperature elevation treatment was shorter than that of constant temperature treatment. By use of these results, the base temperature to flowering of main apple cultivars in Korea was seemed to $10.0^{\circ}C$, and if the air temperature of Gunwi region rises about $5.0^{\circ}C$ than that of current, the flowering time was estimated to be delayed by 1 week.

A Comparison on the Characteristics of Benzene Exposure between the Coal chemical and Petrochemical refining method during Turnaround (석유 및 석탄화학의 대보수작업중 벤젠노출 특성 비교)

  • Chung, Eun-Kyo;Yu, Gye-Muk;Shin, Jung-Ah;Kwon, Ji-Woon;Park, Hyun-Hee;Chung, Kwang-Jae;Lee, Jong-Han;Lee, In-Seop;Kang, Seong-Kyu;Ryu, Hyang-Woo;Kim, Young-Sun;Lee, Byung-Kyu;Jang, Jae-Kil;Kim, Won;Kim, Jung-Man
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.20 no.3
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    • pp.147-155
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    • 2010
  • This study was conducted to investigate the benzene exposure levels in coal chemical and petrochemical refining industries during BTX turnaround (TA) processes where benzene was being produced. Three companies producing benzene were selected, one coal chemical and two petrochemical industries. TA processes were classified into three stages: shut down, maintenance, and start up. Data was analyzed by classifying the refining method into 2 groups (Petrochemistry, Coal chemistry) for 823 workers. Comparing the data from petrochemical industries with data from a coal chemical refining industry, while benzene concentration levels of long-term samples during TA were not statistically different (p> 0.05), those levels of short-term samples were significantly different (p< 0.001). About 4.79 % of data in petrochemical industries exceed the occupational exposure limits (OELs) of benzene, 1 ppm. In a coal refining methods, about 15.7% exceeded the benzene OELs. The benzene concentrations in maintenance and start up stage of TA for petrochemical refineries were higher than those in a coal chemical refinery (p <0.01). These findings suggest that the coal chemical refining site requires more stringent work practice controls compare to petrochemical refining sites during TA processes. Personal protective equipments including organic respirators should be used by TA workers to protect them from benzene overexposure.