• Nuclear Engineering and Technology
• /
• v.49 no.5
• /
• pp.1010-1018
• /
• 2017

The European Treatment and Disposal of Irradiated Graphite and other Carbonaceous Waste project sought to develop best practices in the retrieval, treatment, and disposal of irradiated graphite including other irradiated carbonaceous waste such as structural material made of graphite, nongraphitized carbon bricks, and fuel coatings. Emphasis was given on legacy irradiated graphite, as this represents a significant inventory in respective national waste management programs. This paper provides an overview of the characteristics of graphite irradiated during its use, primarily as a moderator material, within nuclear reactors. It describes the potential techniques applicable to the retrieval, treatment, recycling/reuse, and disposal of these graphite wastes. Considering the lifecycle of nuclear graphite, from manufacture to final disposal, a number of waste management options have been developed. These options consider the techniques and technologies required to address each stage of the lifecycle, such as segregation, treatment, recycle, and ultimate disposal in a radioactive waste repository, providing a toolbox to aid operators and regulators to determine the most appropriate management strategy. It is noted that national waste management programs currently have, or are in the process of developing, respective approaches to irradiated graphite management. The output of the Treatment and Disposal of Irradiated Graphite and other Carbonaceous Waste project is intended to aid these considerations, rather than dictate them.

• Safety and Health at Work
• /
• v.10 no.2
• /
• pp.166-171
• /
• 2019

Objective: This study explored personal protective equipment (PPE) availability and PPE utilization among interventionalists in the catheterization laboratory, which is a highly contextualized workplace. Methods: This is a cross-sectional study using mixed methods. Participants (108) completed a survey. A hyperlink was sent to the participants, or they were asked to complete a paper-based survey. Purposively selected participants (54) were selected for individual (30) or group (six) interviews. The interviews were conducted at conferences, or appointments were made to see the participants. Logistic regression analysis was performed. The qualitative data were analyzed thematically. Results: Lead glasses were consistently used 10.2% and never used 61.1% of the time. All forms of PPE were inconsistently used by 92.6% of participants. Women were 4.3 times more likely to report that PPE was not available. PPE compliance was related to fit and availability. Conclusions: PPE use was inconsistent and not always available. Improving the culture of radiation protection in catheterization laboratories is essential to improve PPE compliance with the aim of protecting patients and operators. This culture of radiation protection must include all those involved including the users of PPE and the administrators and managers who are responsible for supplying sufficient, appropriate, fitting PPE for all workers requiring such protection.

• Nuclear Engineering and Technology
• /
• v.53 no.4
• /
• pp.1378-1389
• /
• 2021

TRIUMF, Canada's particle accelerator centre, is constructing a new high-power ISOL (Isotope Separation On-Line) facility called ARIEL (Advanced Rare IsotopE Laboratory). Thick porous targets will be bombarded with up to 48 kW of 480 MeV protons from TRIUMF's cyclotron, or up to 100 kW of 30 MeV electrons from a new e-linac, to produce short-lived radioisotopes for a variety of applications, including nuclear astrophysics, fundamental nuclear structure and nuclear medicine. For efficient release of radioisotopes, the targets are heated to temperatures approaching 2000 ℃, and are exposed to GSv/h level radiation fields resulting from intended fissions and spallations. Due to these conditions, the operational life for each target is only about five weeks, calling for frequent remote target exchanges to limit downtime. A few days after irradiation, the targets have a residual radiation field producing a dose rate on the order of 10 Sv/h at 1 m, requiring several years of decay prior to shipment to a national disposal facility. TRIUMF is installing new remote handling infrastructure dedicated to ARIEL, including hot cells and a remote handling crane. The system design applies learnings from multiple existing facilities, including CERN-ISOLDE, GANIL-SPIRAL II as well as TRIUMF's ISAC (Isotope Separator and ACcelerator).

• Journal of Distribution Science
• /
• v.21 no.6
• /
• pp.119-129
• /
• 2023

Purpose: The study is developed in order to describe the trends of scientific production of blockchain technologies for sustainability within the supply chains. Research design, data and methodology: This study is developed from the documentary field from the application of bibliometric techniques to analyze the trends of scientific production indexed in the Scopus database, for which processing is carried out in the R and VOS Viewer software. Results: The results show a total of 461 documents, of which 58% of the articles, 17% are conference articles and the remaining 25% are made up of other formats. Conclusions: 78% of the articles are concentrated in the years 2020, 2021 and 2022. India, United Kingdom, China, United States and Italy are the countries where 70% of all the publications were published. 23% of the articles have been published in four journals: Sustainability (Switzerland), Journal of Cleaner Production, Computers and Industrial Engineering and Business Strategy and the Environment. Sarkis, J. is the author with the most published articles with fifteen publications and, finally, 13% of the total publications were concentrated in: Uttaranchal University, Yasar University, Malaviya National Institute of Technology, Centro Di Ricerca Ingegneria e Trasformazioni Agroalimentari and University of Hong Kong.

• The Bulletin of The Korean Astronomical Society
• /
• v.45 no.1
• /
• pp.35.3-36
• /
• 2020

The Time Domain Field is one of the future GTO program fields of JWST(JWST/GTO TDS), surveying about 14' diameter field at the North Eliptical Pole(NEP) with NIRCam/NIRISS. As a part of the multi-wavelength study of the field, we have obtained SCUBA-2 850㎛ mapping which reaches a depth of σrms = 0.9mJy/beam and detect 93 sources at S/N > 3.5 ― which are expected to be highly star-forming (SFR>400M◉/yr) galaxies at z ≳ 1.5-4 and pinpoint the location at <0. " 1 accuracy of 68 sub-mm sources by identifying VLA 3GHz radio counterparts. In this talk, we will introduce the SCUBA-2 JWST/GTO TDS project and the newly discovered sub-mm sources in this field.

• ALGAE
• /
• v.26 no.2
• /
• pp.181-192
• /
• 2011

Ballasting and deballasting of shipping vessels in foreign ports have been reported worldwide as a vector of introduction of non-native aquatic plants and animals. Recently, attention has turned to ballast water as a factor in the global increase of harmful algal blooms (HABs). Many species of microalgae, including harmful dinoflagellate species, can remain viable for months in dormant benthic stages (cysts) in ballast sediments. Over a period of four years, we surveyed ballast water and sediment of ships docked in two ports of Tampa Bay, Florida, USA. Sampling conditions encountered while sampling ballast water and sediments were vastly different between vessels. Since no single sample collection protocol could be applied, existing methods for sampling ballast were modified and new methods created to reduce time and labor necessary for the collection of high-quality, qualitative samples. Five methods were refined or developed, including one that allowed for a directed intake of water and sediments. From 63 samples, 1,633 dinoflagellate cysts and cyst-like cells were recovered. A native, cyst-forming, harmful dinoflagellate, Alexandrium balechii (Steidinger) F. J. R. Taylor, was collected, isolated, and cultured from the same vessel six months apart, indicating that ships exchanging ballast water in Tampa Bay have the potential to transport HAB species to other ports with similar ecologies, exposing them to non-native, potentially toxic blooms.

• Journal of the Korean Institute of Gas
• /
• v.22 no.2
• /
• pp.1-20
• /
• 2018

Despite many measures, still from time to time catastrophic events occur, even after reviewing potential scenarios with HAZID tools. Therefore, it is evident that in order to prevent such events, answering the question: "What can go wrong?" requires more enhanced HAZID tools. Recently, new system based approaches have been proposed, such as STPA (system-theoretic process analysis) and Blended Hazid, but for the time being for several reasons their availability for general use is very limited. However, by making use of available advanced software and technology, traditional HAZID tools can still be improved in degree of completeness of identifying possible hazards and in work time efficiency. The new HAZID methodology proposed here, the Data-based semi-Automatic HAZard IDentification (DAHAZID), seeks to identify possible scenarios with a semi-automated system approach. Based on the two traditional HAZID tools, Hazard Operability (HAZOP) Study and Failure Modes, Effects, and Criticality Analysis (FMECA), the new method will minimize the limitations of each method. This will occur by means of a thorough systematic preparation before the tools are applied. Rather than depending on reading drawings to obtain connectivity information of process system equipment elements, this research is generating and presenting in prepopulated work sheets linked components together with all required information and space to note HAZID results. Next, this method can be integrated with proper guidelines regarding process safer design and hazard analysis. To examine its usefulness, the method will be applied to a case study.

• Elastomers and Composites
• /
• v.45 no.4
• /
• pp.263-271
• /
• 2010

Intermittent CSR testing was used to investigate the degradation of an FKM O-ring, also the prediction of its life-time. An intermittent CSR jig was designed taking into consideration the O-ring's environment under use. The testing allowed observation of the effects of friction, heat loss, and stress relaxation by the Mullins effect. Degradation of O-rings by thermal aging was observed between 60 and $160^{\circ}C$. In the high temperature of range ($100-160^{\circ}C$) O-rings showed linear degradation behavior and satisfied the Arrhenius relationship. The activation energy was about 60.2 kJ/mol. From Arrhenius plots, predicted life-times were 43.3 years and 69.9 years for 50% and 40% failure conditions, respectively. Based on TTS (time-temperature superposition) principle, degradation was observed at $60^{\circ}C$, and could save testing time. Between 60 and $100^{\circ}C$ the activation energy decreased to 48.3 kJ/mol. WLF(William-Landel-Ferry) plot confirmed that O-rings show non-linear degradation behavior under $80^{\circ}C$. The life-time of O-rings predicted by TTS principle was 19.1 years and 25.2 years for each failure condition. The life-time predicted by TTS principle is more conservative than that from the Arrhenius relationship.

• Journal of the korean society of oceanography
• /
• v.35 no.3
• /
• pp.129-152
• /
• 2000

The Cheju Current (CC), defined here as a mean eastward flow in the Cheju Strait, mostly carries water of high temperature and salinity originating from the Kuroshio in winter and spring, the Cheju Warm Current Water (CWCW). The strong core of the eastward component of the CC is found close to Cheju Island (Cheju-Do, hereafter) in winter and spring with a peak speed of about 17.0 cm/s. The eastward flow weakens towards the northern Cheju Strait, and a weak westward flow occurs occasionally close to the southern coast of Korea. The volume transport ranges from 0.37 to 0.45 Sv(1 Sv=10$^6$ m$^3$/s) in winter and spring. Seasonal thermocline and harocline are formed in summer and eroded in November. The occurrence of the CWCW is confined in the southern Cheju Strait close to Cheju-Do below the seasonal thermocline in summer and fall, and cold water occupies the lower layer north of the CWCW which is thought to be brought into the area from the area west of Cheju-Do along with the CWCW. Stratification acts to increase both the speed of the CC with a peak speed of greater than 30 cm/s and the vertical shear of the along-strait currents. The strong core of the CC detached from the coast of Cheju-Do and shifted to the north during the stratified seasons. The volume transport in summer and fall ranges 0.510.66 Sv, which is about 1.5 times larger than that in winter and spring. An annual cycle of the cross-strait sea level difference shows its maximum in summer and fall and minimum in winter and spring, whose tendency is consistent with the annual variability of the CC and its transport estimated from the ADCP measurements. Moored current measurements west of Cheju-Do indicate the clockwise turning of the CC, and the moored current measurements in the Cheju Strait for 1530 days show the low-frequency variability of the along-strait flow with a period of about 37 days.

• Parasites, Hosts and Diseases
• /
• v.51 no.3
• /
• pp.319-325
• /
• 2013

This study describes the seasonal distribution of larvae, nymph, and adult life stages for 3 species of ixodid ticks collected by tick drag and sweep methods from various habitats in the Republic of Korea (ROK). Grasses less than 0.5 m in height, including herbaceous and crawling vegetation, and deciduous, conifer, and mixed forests with abundant leaf/needle litter were surveyed at United States (US) and ROK operated military training sites and privately owned lands near the demilitarized zone from April-October, 2004 and 2005. Haemaphysalis longicornis Neumann adults and nymphs were more frequently collected from April-August, while those of Haemaphysalis flava Neumann and Ixodes nipponensis Kitaoka and Saito were collected more frequently from April-July and again during October. H. longicornis was the most frequently collected tick in grass habitats (98.9%), while H. flava was more frequently collected in deciduous (60.2%) and conifer (57.4%) forest habitats. While more H. flava (54.1%) were collected in mixed forest habitats than H. longicornis (35.2%), the differences were not significant. I. nipponensis was more frequently collected from conifer (mean 8.8) compared to deciduous (3.2) and mixed (2.4) forests.