• Ocean and Polar Research
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• v.43 no.4
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• pp.321-334
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• 2021

'Marine mammals-based observations' refers to data acquisition activities from marine mammals by instrumenting CTD (Conductivity-Temperature-Depth) sensors on them for recording vertical profiles of ocean variables such as temperature and salinity during animal diving. It is a novel data collecting platform that significantly improves our abilities in observing extreme environments such as the Southern Ocean with low cost compared to the other conventional methods. Furthermore, the system continues to create valuable information until sensors are detached, expanding data coverage in both space and time. Owing to these practical advantages, the marine mammals-based observations become popular to investigate ocean circulation changes in the Southern Ocean. Although these merits may bring us more opportunities to understand ocean changes, the data should be carefully qualified before we interpret it incorporating shipboard/autonomous vehicles/moored CTD data. In particular, we need to pay more attention to salinity correction due to the usage of an unpumped-CTD sensor tagged on marine mammals. In this article, we introduce quality control methods for the marine mammals-based CTD profiles that have been developed in recent studies. In addition, we discuss strategies of quality control specifically for the seal-tagging CTD profiles, successfully having been obtained near Terra Nova Bay, Ross Sea, Antarctica since February 2021. It is the Korea Polar Research Institute's research initiative of animal-borne instruments monitoring in the region. We anticipate that this initiative would facilitate collaborative efforts among Polar physical oceanographers and even marine mammal behavior researchers to understand better rapid changes in marine environments in the warming world.

• Ocean and Polar Research
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• v.31 no.4
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• pp.339-347
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• 2009

It is possible to obtain accurate temperature and salinity profiles of the oceans using a SBE 911plus CTD and accompanying data conversion packages. To obtain highly accurate results, CTD data needs to be carefully processed in addition to proper and regular maintenance of the CTD itself. Since the manufacturer of the CTD provides tools that are necessary for post processing, it is possible to conduct proper processing without too much effort. Some users, however, are not familiar with all of the processes and inadvertently ignore some of these processes at the expense of data quality. To draw attention to these and other similar issues, we show how it is possible to improve data quality by utilizing a few extra processes to the standard or default data process procedures with CTD data obtained from the equatorial Eastern Pacific between 2001 and 2005, and 2007. One easy step that is often ignored in the standard data process procedure is "wild edit", which removes abnormal values from the raw data. If those abnormal values are not removed, the abnormality could spread vertically during subsequent processes and produce abnormal salinity in a range much wider than that of the raw data. To remove spikes in salinity profiles the "align CTD" procedure must be carried out not with the default values included in the data processing software but with a proper time constant. Only when "cell thermal mass" correction is conducted with optimal parameters, we can reduce the difference between upcast and downcast, and obtain results that can satisfy the nominal accuracy of the CTD.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.9 no.4
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• pp.204-211
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• 2004

Autonomous profiling CTD floats are a useful tool for observing the oceans. We, however, cannot perform post-deployment calibration of the CTD's attached to the floats, and the assessment of the accuracy and stability of the profile data from the floats is one of the important issues in the delayed mode quality control of the profiles. Variations in salinity in the intermediate level of East Sea is comparable to the accuracy of salinity data required by the international Argo Program, which is 0.01. Therefore, we can assess the credibility of salinity data from the floats deployed in the East Sea using three independent methods while considering the East Sea as a salinity calibration bath. The methods utilized here are 1) comparison of high quality CTD data and float data obtained at similar locations at similar time, 2) comparison of float data obtained at similar locations at similar time, and 3) investigation of long term stability and accuracy of salinity data from parking depths. All three methods show that without any calibration, the salinity data satisfy the accuracy criterion by the Argo Program. While assuming that the intermediate level temperature in the East Sea is as homogeneous as the salinity, we have applied the three methods to temperature data. We found that the accuracy of temperature reading is 0.01$^{\circ}C$, which is about twice larger than the requirement by the Argo Program, 0.005$^{\circ}C$. This does not mean that the temperature readings are inaccurate, because the intermediate level temperature does vary spacially and temporally more than the accuracy interval required by the Argo Program. If we take into account the variation in the intermediate level temperature, the accuracy of temperature data from the floats is not significantly different from that proposed by the Argo Program. Therefore, one could use both temperature and salinity profiles from the floats assessed in this study without calibration.

• Ocean and Polar Research
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• v.36 no.1
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• pp.77-85
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• 2014

The quality control of ocean observations data is becoming a major issue as real-time observational data and information services have increased recently. Therefore, it is necessary for oceanographic instruments to calibrate. In this paper, we first introduce the CTD calibration system and traceability. Next, CTD calibration procedures and estimation of uncertainty of measurement are described. The expanded uncertainty (k = 2) of the temperature, pressure and conductivity are 0.$0.003^{\circ}C$, $6.0{\times}10^{-5}$ and 0.006 mS/cm respectively. Finally, the excellence of CTD calibration and its measurement capability has been proven by comparing the inter-calibration result of KIOST and Sea-Bird Electronics (SBE). CTD calibration residuals are less than ${\pm}0.0001^{\circ}C$, ${\pm}0.001$ MPa, ${\pm}0.0001$ S/m for SBE 3plus temperature sensor, SBE 19plus pressure sensor and SBE 4C conductivity sensor respectively.

• Journal of Environmental Science International
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• v.17 no.12
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• pp.1353-1361
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• 2008

Quality control of Argo(Array for Real-time Geostrophic Oceanography) data is crucial by reason that salinity measurements are liable to experience some drift and offset due to biofouling, contamination of sensor and wash-out of biocide. The automated Argo real-time quality control has a limit of sorting data quality, so that WJO program is adopted as standardized method of Argo delayed mode quality control (DMQc) in the world that is a precise quality control method. We conducted DMQC on pressure, temperature and salinity measured by Argo floats in the Pacific Ocean including expert evaluation. Particularly, salinity data were corrected using WJO program. 4 salinity profiles of Argo delayed mode were compared with nearby in situ CTD data and other Argo data in deep layer where oceanographic conditions are stable in time and space. The differences of both salinities were lower than target accuracy of Argo. As compared with the difference of salinities before DMQC, those after DMQC decreased by 60-80 percent. Quality of delayed mode salinity data seemed to be improved correcting salinity data suggested by WJO program.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.249-258
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• 2010

This study seeks to improve NFRDI Serial Oceanographic observation (NSO) system which has been operated at current observation stations in the Korean Seas since 1961 and suggests the direction of NSO for practical use of Korean operational oceanographic system. For improvement, data handling by human after CTD (Conductivity-Temperature-Depth) observation on the deck, data transmission, data reception in the land station, and file storage into database need to be automated. Software development to execute QA/QC (Quality Assurance/Quality Control) of real-time oceanographic observation data and to transmit the data with conversion to appropriate format automatically will help to accomplish the automation. Inmarsat satellite telecommunication systems with which have already been equipped on board the current observation vessels can realize the real-time transmission of the data. For the near real-time data transmission, CDMA (Code Division Multiple Access) wireless telecommunication can provide efficient transmission in coastal area. Real-time QA/QC procedure after CTD observation will help to prevent errors which can be derived from various causes.

• Journal of Preventive Medicine and Public Health
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• v.32 no.1
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• pp.48-59
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• 1999

Objectives. This study was conducted to evaluate the association between upper extremity musculoskeletal symptoms and Rapid Upper Limb Assessment(RULA) in vehicle assembly line workers. The goal of this study is to show the feasibility of RULA as a checklist for work related musculoskeletal symptoms (WMSDs) in Korean workers. Methods. The total number of 199 people from the department of assembly and 115 people from the department of Quality Control(QC) in automotive plant were subjects for this cross sectional study. A standard symptom questionnaire survey has been used for the individual characteristics, work history, musculosketal symptoms and non-occupational covariates. The data were obtained by applying one-on-one interview for the all subjects. RULA has been applied for ergonomic work posture analysis and the primary ergonomic risk sure was computed by RULA method. Association between upper extremity musculoskeletal symptoms and RULA were assessed by multiple logistic regression analysis. Results. A total of 314 workers was examined. The prevalence of musculoskeletal symptoms by NIOSH case definition was 62.4%. The distribution of musculoskeletal symptoms by the part of the body turned out to be following; back:41.4%, neck: 32.8%, shoulder: 26.4%, arm: 10.5% and hand:29.3%. The relationship of the individual RULA scores were statistically significant for the prevalence of musculoskeletal symptoms. As the result of the multiple logistic regressioin analysis, grand final score (OR=2.250 95% CI: 1.402-3.612) was associated with musculoskeletal symptoms in any part of the body.; upper arm score(OR=1.786 95% CI: 1.036-3.079) and posture score A(OR=1.634 95% CI: 1.016-2.626) in neck; muscel use score(OR=3.076 95% CI:1.782-5.310) and posture score A(OR=1.798 95% CI: 1.072-3.017) in shoulder; upper arm score(OR=1.715 95% CI: 1.083-2.715) and muscel use score(OR=2.057 95% CI:1.303-3.248) in neck & shoulder; muscle use score(OR=10.662 95% CI: 3.180-35.742) in arm; writst/wist score(OR=2.068 95% CI: 1.130-3.786) and muscle use score(OR=2.215 95% CI: 1.284-3.819) in hand & wrist.; muscle use score of trunk (OR=2.601 95% CI: 1.147-5.901) in back. Conclusions. Musculoskeletal symptoms of the extremities were strongly associated with individual RULA body score. These results show that RULA can be used as a useful assessment tool for the evaluation of musculoskeletal loading which is known to contribute to work-related musculoskeletal disorders. RULA also can be used as a screening tool or incorporated into a wider ergonomic assessment of epidemiological, physical, mental, environmental and organizational factors. As shown in this study, complement of the analysis system for the other risk factors and characterizing between the upper limb and back part will be needed for future work.