• Fire Science and Engineering
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• 제28권1호
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• pp.37-43
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• 2014

The high predictive performance of fire detector models is essentially needed to assure the reliability of fire and evacuation modeling in the process of Performance-Based fire safety Design (PBD). The main objective of the present study is to measure input information in order to predictive the accurate activation time of fixed temperature heat detectors adopted in Fire Dynamics Simulator (FDS) as a representative fire model. To end this, Fire Detector Evaluator (FDE) which could be measured the device properties of detector was used, and the spot-type fixed temperature heat detectors of two thermistor types and one bimetal type were considered as research objectors. Activation temperature and Response Time Index (RTI) of detectors required for the fire modeling were measured, and then the RTI was measured for ceiling jet flow and vertical jet flow in consideration of the install location of detectors. The results of fire modeling using measured device properties were compared and validated with the experimental results of full-scale compartment fires. It was confirmed that, in result, the numerically predicted activation time of detector showed reasonable agreement with the measured activation time.

• The Korean Journal of Nuclear Medicine
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• 제29권1호
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• pp.54-60
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• 1995

Medical Internal Radiation Dose(MIRD) schema was developed for calculating the absorbed dose from the administered radiopharmaceuticals. With the biological distribution data and the physical properties of the radionuclide we can estimate the absorbed dose by the MIRD schema. For the thyroid cancer patients received $^{131}I$ therapy, the absorbed dose to the bone marrow is the limiting factor to the administered dose, and the duration of admission is deter-mined by the retained activity in the whole body. To monitor the whole body radioactivity, we used Eberline Smart 200 system using ionization chamber as a detector. With the time activity curve of the whole body, total body residence time was obtained. From the ICRP publication 53, the residence times of the source organs, such as kidney, urinary bladder content and stomach, were used to calculate the absorbed doses of the target organs, such as stomach, red marrow, bladder wall and remaineder total body. In 8 thyroid cancer patients with 175 mci of $^{131}I$ administered orally, the mean absorbed dose in the bladder wall was 375.1, in the stomach 285.1, red marrow 25.4 and total body 22.4 rad respectively. For the monitoring of the large administered activity, this method seemed to be quite useful.

• Journal of the Korean Magnetics Society
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• 제25권4호
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• pp.123-128
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• 2015

The iron is an element having a high yield strength, mechanical hardness, good electrical conductivity, and also it has been used in various fields because of ease machining. In bridges have been used tendon made of a steel wire for large loads and light weight. Tension measurement of tendon employed in PreStressed Concrete (PSC) bridge is very important for the bridge safety check. NDT (Non-Destructive Testing) is essential for the safety check, however, magnetic NDT is difficult to apply due to the non-linear magnetization curve and hysteresis loop in the magnetic properties. In this work, for basic study of magnetic NDT application, we have constructed a B-H loop measuring system for 7-strand tendon of which diameter is 15.5 mm, and which can apply tensile stress up to 2.0 GPa. We have measured hysteresis loops of two kinds of tendons under different tensile stress. Amplitude permeability and maximum magnetic induction near knee show the most sensitive and high linearity depends on tensile stress. Relative amplitude permeability was decreased from 500 to 200 and maximum magnetic flux density changed 0.6 T.

• Proceedings of the Safety Management and Science Conference
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• 대한안전경영과학회 2011년도 춘계학술대회
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• pp.731-746
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• 2011

The successful and sustainable growth of SMEs depends on their ability of strengthen their competitiveness in quality and cost and service more than anything else as a fundamental of operation. Among these key competitive factors of SMEs, quality is the most critical factor in manufacturing business fields. Because quality strongly influence cost and service performance on this manufacturing business field. There are many different ways to improve the quality performance but it needs proper management decision to choose the best way what can maximize outputs with minimum inputs. And it needs effective measurement methods and some indicators to analysis the quality performance properly. The quality cost is one of the simplest key indicators to measure the quality performance and the effectiveness of quality related management decisions. The major purpose of this study is to diagnose the categorized current level of actual quality cost of local SMEs to maximize their quality management effectiveness through comparing their level with others what's expressed in early studies. In this study, through survey on local SMEs, we found that their average annual quality cost ratio versus turnover - Total amount of annual quality cost divided by annual turnover - is around 3.69% excluded some SME's performances what have different quality control measures with others. And we found some results what corresponded with the early studies on the correlations between those categorized quality costs factors and some discrepancies between some of the literature model and the early case study results as follows. There were negative correlations between the Prevention costs and the External failure costs, and the Appraisal costs and the External failure costs, and there was positive correlation between the Appraisal costs and Internal failure costs same as early studies. But, we couldn't found any strong negative correlations between the Cost of control - Preventive costs & Appraisal costs - and the Cost of Failure of control - Internal & External failure costs -. It reveals not only the lack of effectiveness on their preventive or appraisal activities but also it can reveal there were so many effective ways to prevent the failure costs properly such as some innovative investment on Factory automation includes Error Proofing and more preventive actions to improve the effectiveness of the typical management methods likes CE (Concurrent Engineering), APQP (Advanced Product Quality Planning), FMEA (Failure Mode & Effect Analysis) etc.

• Journal of the Korea Safety Management & Science
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• 제10권4호
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• pp.297-307
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• 2008

At the spots of enterprises experiencing rapid environmental changes, necessity for ceaseless managemental innovation is raised. We can't deny that management quality is also a part of such managemental innovation. Introduction of management quality by an organization is different from introduction of other individual innovative techniques. Management quality is not one time project but complete historical change program to be pursued continuously. Furthermore, it must be understood as a strategic 'Quality Journey' looking for far future of an organization. Malcolm Baldrige Model has been increasingly used in Korea as a global standard for management quality. The model, however, has shown a number of limitations in application due to nonsystematic elements in the implementation process. The deployment process of the model should be detailed through a real world case study. In this research, we proposed a quality evaluation standard model which is suitable for the Korean public enterprise based on the Malcolm Baldrige Non-profit Criteria, and examined the model. A 7-Point Likert Scale was used based on the seven categories within the 2007 Malcolm Baldrige Non-profit Criteria: Leadership, Strategic Planning, Customer and Market Focus, Management Analysis and Knowledge Management, Workforce Focus, Process Management, and Results. Furthermore, we analysed the validity and causal relationship among the factors within the model. Through the above case study, following common factors for successful Malcolm Baldrige Model have been derived. The following is a summary of the results of this study. First, for Malcolm Baldrige Model management, needs powerful support Leadership. Second, for Malcolm Baldrige Model management, needs systematic Strategic Planning. Third, for Malcolm Baldrige Model management, needs the continuous Customer and Market Focus. Fourth, for Malcolm Baldrige Model management, needs systematic Measurement Analysis and Knowledge Management. Five, for Malcolm Baldrige Model management, needs systematic Workforce Focus. Six, for Malcolm Baldrige Model management, needs systematic Process Management. The finding are surely necessary factors to arrange the human resource management for upgraded management quality, those factors help to explain why all enterprises consider human resource as the strategic view.

• Journal of the Korean Institute of Gas
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• 제24권2호
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• pp.44-49
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• 2020

In this paper, a measuring circuit is designed through analyzing manufacture specification of the sensor based on MOS. And the best input-output polynomial are induced that really gas sensors are used in gas safety management industrial fields. Response characteristics of a MOS gas sensor is analysed by through sensor's output voltages are measured after standard gases with six kinds of concentrations are manufactured and are injected to the sensor. A lookup table is created by relations of sensor's output voltages by injecting gases with other concentrations. Because data of the formed lookup table are equal interval, a polynomial can be induced of method of approximation function. So the 5th polynomial of input-output for a sensor is defined, coefficients are calculated by using least squares method, and the 5th polynomial is completed for representing characteristics of the sensor. If the proposed polynomial is applied to gas leak detectors, an inverse transformation of polynomial and programing of array codes are recreated. In this research, polynomial is implemented with array types that intervals of values of a lookup table are one-fifth sampled and interpolated. The performance of proposed 5th calibration equation is verified that errors are reduced than a linear expression when tests are performed by measurement of concentrations against injection of standard gases.

• Smart Structures and Systems
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• 제20권5호
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• pp.549-562
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• 2017

The US railroad network carries 40% of the nation's total freight. Railroad bridges are the most critical part of the network infrastructure and, therefore, must be properly maintained for the operational safety. Railroad managers inspect bridges by measuring displacements under train crossing events to assess their structural condition and prioritize bridge management and safety decisions accordingly. The displacement of a railroad bridge under train crossings is one parameter of interest to railroad bridge owners, as it quantifies a bridge's ability to perform safely and addresses its serviceability. Railroad bridges with poor track conditions will have amplified displacements under heavy loads due to impacts between the wheels and rail joints. Under these circumstances, vehicle-track-bridge interactions could cause excessive bridge displacements, and hence, unsafe train crossings. If displacements during train crossings could be measured objectively, owners could repair or replace less safe bridges first. However, data on bridge displacements is difficult to collect in the field as a fixed point of reference is required for measurement. Accelerations can be used to estimate dynamic displacements, but to date, the pseudo-static displacements cannot be measured using reference-free sensors. This study proposes a method to estimate total transverse displacements of a railroad bridge under live train loads using acceleration and tilt data at the top of the exterior pile bent of a standard timber trestle, where train derailment due to excessive lateral movement is the main concern. Researchers used real bridge transverse displacement data under train traffic from varying bridge serviceability levels. This study explores the design of a new bridge deck-pier experimental model that simulates the vibrations of railroad bridges under traffic using a shake table for the input of train crossing data collected from the field into a laboratory model of a standard timber railroad pile bent. Reference-free sensors measured both the inclination angle and accelerations of the pile cap. Various readings are used to estimate the total displacements of the bridge using data filtering. The estimated displacements are then compared to the true responses of the model measured with displacement sensors. An average peak error of 10% and a root mean square error average of 5% resulted, concluding that this method can cost-effectively measure the total displacement of railroad bridges without a fixed reference.

• Journal of the Society of Cosmetic Scientists of Korea
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• 제39권3호
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• pp.251-257
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• 2013

In this study, ultraviolet protection factor (Sun Protection Factor, SPF) was investigated to provide basic data for subject safety and research of ultraviolet (UV) irradiation test in the future. Trial subjects (395 people) of skin type I, II, and III were evaluated according to skin type standard table. After measuring the skin color using a colorimeter, ITA (Individual Typology Angle) value was calculated. Subjects with 28 and above ITA value were positioned comfortably to be UV irradiated for 60 s and erythema was evaluated 24 hours after application. MED (Minimal Erythema Dose) was investigated where the minimal amount of erythema existed among UVB irradiated area. Statistical analysis was investigated using Statistical Package the Social Sciences program. As a result, the darker skin color results in the higher MED value since the higher skin type number results increased MED value and female has higher MED value than male since female has darker skin type than male. There was no relation between MED difference by ages in all different ages. However, it is hard to draw a conclusion as above since the number of subjects were not sufficient to support statistical significance for MED values by different ages. However, MED values by skin types obtained through this study can be used as a standard when MED value is expected to evaluate efficacy of sunscreen product and as basic data for further safety of clinical researches.

• Journal of the Korean Society of Marine Environment & Safety
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• 제23권2호
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• pp.177-186
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• 2017

This paper attempts to quantitatively assess the public value that has been assigned to this government plan by employing a contingent valuation technique. Data gathering performed that professional research firm administrated a face-to-face national survey of 1,000 randomly-selected households. A one-and-one-half-bound model was adopted to elicit willingness to pay (WTP) responses, and the payment vehicle used was income tax. The WTP model used in this study is based on a utility difference approach and the spike model. The results showed that the public value of conserving green turtles was estimated to be 2,570 Korean Won per household over the next 10 years as of 2016, statistically significant at the 1% level. Expanding the values considered to include the national population gives a public value of 48.7 billion Korean Won. Thus, the public value of rescuing, rehabilitating, and releasing green turtles that have been caught by fishermen, collided with fishing boats, and died in nets through the government program is not small.

• Fire Science and Engineering
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• 제27권4호
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• pp.27-34
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• 2013

The high prediction performance of fire detector models is essentially needed to assure the reliability of fire and evacuation modeling in the process of PBD (Performance Based fire safety Design). The main objective of the present study is to measure input information in order to predict the accurate activation time of smoke detector into a Large Eddy Simulation (LES) fire model such as FDS (Fire Dynamics Simulator). To end this, FDE (Fire Detector Evaluator) which can measure the device properties of detector was developed, and the input information of Heskestad and Cleary's models was measured for a ionization smoke detector. In addition, the activation times of smoke detectors predicted using default values into FDS and measured values in the present study were systematically compared. As a result, the device properties of smoke detector examined in the present study showed a significant difference compared to the default values used into FDS, which resulted in the considerable difference of up to 15 minutes or more in terms of the activation time of smoke detector. The database (DB) on device properties of various smoke and heat detectors will be built to improve the reliability of PBD in future studies.