• Title/Summary/Keyword: Self-exposure

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Evaluation of Clinical Availability for Shoulder Forced Traction Method to Minimize the Beam Hardening Artifact in Cervical-spine Computed Tomography (CT) (경추부 전산화단층촬영에서 선속 경화 인공물을 최소화하기 위한 견부 강제 견인법에 대한 임상적 유용성 평가)

  • Kim, Moonjeung;Cho, Wonjin;Kang, Suyeon;Lee, Wonseok;Park, Jinwoo;Yu, Yunsik;Im, Inchul;Lee, Jaeseung;Kim, Hyeonjin;Kwak, Byungjoon
    • Journal of the Korean Society of Radiology
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    • v.7 no.1
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    • pp.37-44
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    • 2013
  • In study suggested clinical availability to shoulder forced traction method in term of quality of image, the patient's convenience and stability, according to whether to use of shoulder forced traction bend using computed tomography(CT) that X-ray calibration and various mathematic calibration algorithm application can be applied by AEC. To achieve this, 79 patients is complaining of cervical pain oriented that shoulder forced traction bend use the before and after acquires lateral projection scout image and transverse image. transverse image of a fixed size in concern field of pixel and figure the average HU value compare that quantitative analysis. Artifact and pixel and resolution to qualitative clinical estimation image analysis. the patient feel inconvenience degree that self-diagnosis survey that estimate. As a result, lateral projection scout image if you used shoulder forced traction bend for the depicted has been an increase in the number of a cervical vertebrae. transverse image concern field shoulder forced traction bend use the before and after for pixel and the average HU-value changes was judged to be almost irrelevant. Artifact and resolution and contrast, in qualitative analysis of the results relating the observer to the unusual result. So, the patients of 82.27% complained discomfort that use of shoulder forced traction bend in self-diagnosis survey. No merit of medical image by using of bend from result was analyzed quality of image to quantitative and qualitative method judged. Nowadays, CT is supplied possible revision of quality of radiation by reduction of slice and automatic exposure controller, etc and application of preconditioning filter process due to various mathematic revision algorithm. So, image noise by beam hardening artifact should not be a problem. shoulder forced traction bend of use no longer judged clinically availability because have not influence of image quality and give discomfort, have extra dangerousness.

The Effect of Various Coffees on the Color Stability of Self-cured Temporary Crown Resin (커피종류에 따른 자가중합형 임시치관용 레진의 색 안정성에 관한 연구)

  • Hwang, Su-Hyun;Yu, Ji-Su;Han, Yang-Keum
    • Journal of dental hygiene science
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    • v.12 no.4
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    • pp.342-347
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    • 2012
  • This study is a temporary crowns and the period you want to avoid the exposure of the coffee girl polymerization types is difficult given the temporary tolerance by producing resin. 1. Change of brightness ($L^*$) edge in time increases, distilled water, Americano, Cafelatte, Vanillalatte was reduced to a significant level of brightness (p<.001). The most significant decrease in brightness of the Americano, which tend to grow out of a Cafelatte, Vanillalatte, which was followed by distilled water. 2. Change of redness ($a^*$) edge in time tend to increase saturation increases, the redness value of Americano, Cafelatte, redness value was a statistically significant difference in distilled water and Vanillalatte (p<.05) was not significant. 3. Change of yellowness ($b^*$) edge in time tend to increase saturation increases, the yellowness value of Cafelatte, Vanillalatte, Americano, except for distilled water at the saturation of yellowness value were no statistically significant (p<.05). 4. Change of color difference (${\Delta}E^*$) in order of (Americano>Cafelatte>Vanillalatte) as time of immersion increases change of color difference appear and no statistically significant (p<.05). Americano, the edge, since there can be more than chrominance is 3.3 uses station than a Vanillalatte, Cafelatte and discoloration when edge in 28, since even in the one to two difficult to distinguish with the naked eye as a discoloration. It was no difference statistically in color difference (${\Delta}E^*$) value in distilled water (p>.05).

Measuring the Third-Person Effects of Public Opinion Polls: Focusing On Online Polls (여론조사보도에 대한 제3자효과 검증: 온라인 여론조사를 주목하며)

  • Kim, Sung-Tae;Willnat, Las;Weaver, David
    • Korean journal of communication and information
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    • v.32
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    • pp.49-73
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    • 2006
  • During the past decades, public opinion polls have become an ubiquitous tool for probing the complexity of people's beliefs and attitudes on a wide variety of issues. Especially since the late 1970s, the use of polls by news organizations has increased dramatically. Along with the proliferation of traditional polls, in the past few years pollsters and news organizations have come to recognize the advantages of online polls. Increasingly there has been more effort to take the pulse of the public through the Internet. With the Internet's rapid growth during the past years, advocates of online polling often emphasize the relative advantages over traditional polls. Researchers from Harris Black International Ltd., for example, argue that "Internet polling is less expensive and faster and offers higher response rates than telephone surveys." Moreover, since many of the newer online polls draw respondents from large databases of registered Internet users, results of online polls have become more balanced. A series of Harris Black online polls conducted during the 1998 gubernatorial and senatorial elections, for example, has accurately projected the winners in 21 of the 22 races it tracked. Many researchers, however, severely criticize online polls for not being representative of the larger population. Despite the often enormous number of participants, Internet users who participate in online polls tend to be younger, better educated and more affluent than the general population. As Traugott pointed out, the people polled in Internet surveys are a "self selected" group, and thus "have volunteered to be part of the test sample, which could mean they are more comfortable with technology, more informed about news and events ... than Americans who aren't online." The fact that users of online polls are self selected and demographically very different from Americans who have no access to the Internet is likely to influence the estimates of what the majority of people think about social or political issues. One of the goals of this study is therefore to analyze whether people perceive traditional and online public opinion polls differently. While most people might not differentiate sufficiently between traditional random sample polls and non representative online polls, some audiences might perceive online polls as more useful and representative. Since most online polls allow some form of direct participation, mostly in the form of an instant vote by mouse click, and often present their findings based on huge numbers of respondents, consumers of these polls might perceive them as more accurate, representative or reliable than traditional random sample polls. If that is true, perceptions of public opinion in society could be significantly distorted for those who rely on or participate in online polls. In addition to investigating how people perceive random sample and online polls, this study focuses on the perceived impact of public opinion polls. Similar to these past studies, which focused on how public opinion polls can influence the perception of mass opinion, this study will analyze how people perceive the effects of polls on themselves and other people. This interest springs from prior studies of the "third person effect," which have found that people often tend to perceive that persuasive communications exert a stronger influence on others than on themselves. While most studies concerned with the political effects of public opinion polls show that exit polls and early reporting of election returns have only weak or no effects on the outcome of election campaigns, some empirical findings suggest that exposure to polls can move people's opinions both toward and away from perceived majority opinion. Thus, if people indeed believe that polls influence others more than themselves, perceptions of majority opinion could be significantly altered because people might anticipate that others will react more strongly to poll results.

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A Study on Activation Characteristics Generated by 9 MeV Electron Linear Accelerator for Container Security Inspection (컨테이너 보안 검색용 9 MeV 전자 선형가속기에서 발생한 방사화 특성평가에 관한 연구)

  • Lee, Chang-Ho;Kim, Jang-Oh;Lee, Yoon-Ji;Jeon, Chan-Hee;Lee, Ji-Eun;Min, Byung-In
    • Journal of the Korean Society of Radiology
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    • v.14 no.5
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    • pp.563-575
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    • 2020
  • The purpose of this study is to evaluate the activation characteristics that occur in a linear accelerator for container security inspection. In the computer simulation design, first, the targets consisted of a tungsten (Z=74) single material target and a tungsten (Z=74) and copper (Z=29) composite target. Second, the fan beam collimator was composed of a single material of lead (Z=82) and a composite material of tungsten (Z-74) and lead (Z=82) depending on the material. Final, the concrete in the room where the linear accelerator was located contained magnetite type and impurities. In the research method, first, the optical neutron flux was calculated using the MCNP6 code as a F4 Tally for the linear accelerator and structure. Second, the photoneutron flux calculated from the MCNP6 code was applied to FISPACT-II to evaluate the activation product. Final, the decommissioning evaluation was conducted through the specific activity of the activation product. As a result, first, it was the most common in photoneutron targets, followed by a collimator and a concrete 10 cm deep. Second, activation products were produced as by-products of W-181 in tungsten targets and collimator, and Co-60, Ni-63, Cs-134, Eu-152, Eu-154 nuclides in impurity-containing concrete. Final, it was found that the tungsten target satisfies the permissible concentration for self-disposal after 90 days upon decommissioning. These results could be confirmed that the photoneutron yield and degree of activation at 9 MeV energy were insignificant. However, it is thought that W-181 generated from the tungsten target and collimator of the linear accelerator may affect the exposure when disassembled for repair. Therefore, this study presents basic data on the management of activated parts of a linear accelerator for container security inspection. In addition, When decommissioning the linear accelerator for container security inspection, it is expected that it can be used to prove the standard that permissible concentration of self-disposal.

A Study of the Evolving Process of Wealthy Major Donors' Sharing Lives in Korea (부유층의 기부과정에 관한 연구)

  • Kang, Chul-Hee;Kim, Mi-Ok
    • Korean Journal of Social Welfare
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    • v.59 no.2
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    • pp.5-38
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    • 2007
  • This study attempts to develop a theory on the evolving process of wealthy major donors' sharing lives in Korea through a grounded theory approach. To conduct this study, the researchers have in-depth interviews with 11 exemplary wealthy major donors who have more than one million US dollars in his or her own asset and donate more than ten thousand US dollars annually. In data analysis, this study identifies 161 concepts on the evolving process of wealthy major donors' sharing lives; and the concepts are categorized with 33 sub-categories and 14 categories. In the paradigm model on the evolving process of wealthy major donors' sharing lives, it is identified that the central phenomenon, 'practicing sharing lives as noblesse oblige', is related with the causal conditions such as 'learning through memories and observation', 'realizing my duties', and 'emphasizing'; and the central phenomenon is related with the contingent conditions such as 'being sensitive to external evaluation', 'having limited information on giving', 'distrusting donation related environments'. The action/interactional sequences such as 'utilizing relationships' and 'strengthening active participation' are accomplished by moderating conditions such as 'having internal and external supports' and 'guiding by firm conviction'. It reveals that as a result, wealthy major donors enjoy the feeling of becoming a ideal and true wealthy person, establish sharing lives as firm and major parts of overall lives, and experience strong desires for better future and society. In this study, 'generous sharing that shares personal heritages and social benefits' is analyzed as a core category; it shows that sharing of wealthy major donors is related to the characteristics of generosity practice based on moral self-benefiting rather than complete altruistic characteristics or self-sacrificial characteristics. The process analysis reveals that it has the following stages: first, initial giving by exposure to causes or requests; second, routine practice of giving; third, evolution of practice of giving with gradual expansion in quantities and qualities; and fourth, living with giving. In the process, the following four types are identified: devoted wealthy donors for sharing, wealthy donors practicing sharing in daily life, wealthy donors practicing sharing with learning on external stimulus, and wealthy donors practicing sharing on empathy. Finally, this study discusses both meanings of identifying and developing a theory on the evolving process of wealthy major donors' sharing lives and implications of the research results in cultivating and developing potential wealthy major donors in Korea.

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Evaluation of Roadmap Image Quality by Parameter Change in Angiography (혈관조영검사에서 매개변수 변화에 따른 Roadmap 영상의 화질평가)

  • Kong, Chang gi;Song, Jong Nam;Han, Jae Bok
    • Journal of the Korean Society of Radiology
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    • v.14 no.1
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    • pp.53-60
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    • 2020
  • The purpose of this study is to identify factors affecting picture quality in Roadmap images, which were studied by varying the dilution rate, collimation field and flow rate of contrast medium. For a quantitative evaluation of the quality of the picture, a 3mm vessel model Water Phantom was self-produced using acrylic, a roadmap image was acquired with a self-produced vascular model Water Phantom, and the SNR(Signal to Noise Ratio) and CNR (Contrast to Noise Ratio) were analyzed. CM:N/S In the study on the change of dilution rate, CM:N/S dilution rate changed to (100%~10%:100%), and the measurement of the roadmap image taken using the vascular model Water Phantom showed that the measurement value of SNR gradually decreased as the N/S dilution rate was increased, and the measurement of CNR was gradually reduced. It was confirmed that the higher the dilution rate of CM:N/S, the lower the SNR and CNR, and also significant image can be obtained at the dilution rate of CM:N/S (100%~70:30%). The study showed the value of SNR and CNR in Roadmap image was increased as the Collimation Field was narrowed to the center of the vascular phantom; the Collimation Field was narrowed to the center of the vessel model by 2cm intervals to 0cm through 12cm. To verify the relationship with Roadmap image and Flow Rate, volume of the autoinjector was kept constant at 15 and the flow rate was gradually increased 1, 2, 3, 4, 5, 6, 7, 8, 9, 10. The value of SNR and CNR of images taken by using water Phantom gradually decreased as the Flow Rate increased, but at Flow Rate 9 and 10, the SNR and CNR value was increase. It was not possible to confirm the relationship with SNR and CNR by ROI mean value and Background mean value. It is considered that further study is needed to evaluate the correlation about Roadmap image and Flow Rate. In conclusion, as the dilution rate of N/S in contrast medium was increased, the value of SNR and CNR was decreased. The narrower the Collimation Field, the higher image quality by increasing value of SNR and CNR. However, it is not confirmed the relationship Roadmap image and Flow Rate. It is considered that appropriate contrast medium concentration to minimize the effects of kidney and proper Collimation Field to improve contrast of image and reduce exposure X-ray during procedure is needed.

On the present bamboo groves of Cholla-nam-do and their proper treatment -No. 1. On the growing stock of reprsentative phyllostachys reticulata grove by county (전라남도(全羅南道)의 죽림현황(竹林現況)과 그 개선대책(改善對策) -제일(第一), 각군별대표고죽림(各郡別代表苦竹林)의 몇가지 죽간형질(竹桿形質)과 축적(蓄積)에 대하여)

  • Chung, Dong Oh
    • Journal of Korean Society of Forest Science
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    • v.2 no.1
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    • pp.19-28
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    • 1962
  • Total area of bamboo groves in Korea which is limited to $37^{\circ}$ north latitude, i.e., to southern part of Chungchung-nam-do Province and Kangwon-do Province, is 3,235ha., but this country must import about 3,000 metric ton's bamboo culms from Japan every year. It may be true that the country is not so fit for economical cultivation of bamboo groves from the view point of climatic condition, but the author believes that self-sufficiency in bamboo is not impossible if some scientific method for improving bamboo groves is introduced to our primitive groves. Keeping this point in his mind the auther tried to study on the bamboo groves in the country, and as the first step set about to investigate the actual state of twenty good bamboo groves located in Cholla-nam-do Province from March, 1961 to January, 1962. This is a report on some characters of bamboo culms and growing stock with samples collected in the present investigation. 1) Numbers of bamboo culm per 0.1ha. are 1,183 in average, 1,840 in maximum and 87.5 in minimum before harvesting. 2) According to owners' saying, 1960 was such an off-year that they could hardly see any yearling bamboos in groves, but in 1961 very many new bamboos are produced as follows: the proportion of the number of yearling bamboos produced this year to that of mature bamboos (over 2 years old) is 58.7% in average; the highest 110.5% and the lowest 16.8%. 3) the average diameter of culms at eye height is 6.5cm, but the biggest diameter comes to 11.2 cm, and the average diameters of yearling and mature bamboos are 6.5cm and 6.6cm respectively. 4) Internode length records 29.4 cm in average, the shortest 21.3 cm and the longest 38.4 cm. Average internode lengths of new culms and mature culms are 27.6 cm and 29.4 cm respectively. This shows that the internode length of new culms is in the decrease to that of maturer's. 5) Through this investigation, it was found that internode length is in the influence of the exposure and density of bamboo groves, i. e., the more the dencity of bamboo groves is and the more the exposure nears the north-east, the longer the internode length becomes (see Table 7 and 8). 6) In the growing stock of bamboo groves, bundles per 0.1ha. amount to 271 sok (unit of bundle) in total average, 445 sok in maximum and 126 sok in minimum. 7) Among twenty typical bamboo groves, chosen in each County in Cholla-nam-do Province, only one passes perfectly by Veda's standard rule* prescribing the good bamboo grove, but the eight groves shown in Table 9 could be recommended as good ones in Cholla-nam-do Province, because the auther believes that those groves may be improved better, if we pay more attention to the management of them. 8) Considering that they have managed their groves carelessly and primitively, and that unfortunately their groves must have faced almost on clear felling over the entire area at the time of the Korean War, we can surely expect much more increments in bamboo groves, if we introduce some scientific methods in managing their groves.

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The Relationship between Insomnia and Somatization According to Types of Work of Firefighters (소방공무원의 직무유형에 따른 불면과 신체화증상과의 관계)

  • Yoon, Heesoo;Ju, Gawon;Lee, Sang Ick;Shin, Chul-Jin;Son, Jung-Woo;Kim, Siekyeong;Park, Hyemi;Lee, Jeong Hwan
    • Korean Journal of Psychosomatic Medicine
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    • v.28 no.1
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    • pp.42-52
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    • 2020
  • Objectives : Firefighters are always under stress due to their job environment, and they are likely to become psychologically vulnerable due to continuous exposure to traumatic events, which is a stressful situation that requires emergency standby at all times. The aims of this study were to examine mental health factors for each division of firefighters and to see the relationship between sleep and somatization symptoms among them. Methods : General characteristics and related inspections were conducted through self-reporting questionnaires for 1,264 firefighters working at Chungbuk fire stations. Several mental health factors were investigated by the Insomnia Severity Index, Severity of somatic symptoms, Impact of Event Scale, Perceived Stress Scale, Resilience Scale, Alcohol Dependent Screening Scale, and the Center for Epidemiologic Studies Depression Scale Depression Scale and Mini-International Neuropsychiatric Interview. Results : Among the mental health variables, the relationship between insomnia and somatization varies significantly depending on types of work. It was reported that the first aid team was significantly higher than the fire suppression and rescue team. Post-traumatic stress, depression and drinking also differ significantly depending on types of work. The first aid team reported more posttraumatic stress than the fire suppression team and more depressed mood than the rescue team. The administration part had more alcohol consumption than the fire suppression or first aid team. Resilience was significantly higher in the rescue team than the first aid team. No significant differences between the types of work about stress and suicide risks. Insomnia, stress, and post-traumatic stress were significant predictors of somatization among firefighters. Above all, insomnia was significant mental health variable affecting somatization. Conclusions : Various mental health factors were different according to the types of work in firefighters. The First aid team was more vulnerable to mental health variables such as insomnia and somatization than other divisions. Insomnia is the most important cause of somatization in firefighters, so it is recommended that they be treated for insomnia and to prepare institutional policies.

The Study on Effects of "the Unsafe Food Program" designed For Improving Children's Eating Habits (유아들의 식습관 개선을 위한 "위험한 먹거리 프로그램"의 효과에 대한 연구)

  • Seo, Sun Suk;Lee, Ju Rhee
    • Korean Journal of Childcare and Education
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    • v.6 no.1
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    • pp.157-176
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    • 2010
  • The purpose of this study was to estimate the effect of "The unsafe food program" designed for improving children's biased eating habits coming from defenceless exposure to the instant food, fast food and adulterated food with MSG and artificial additives with analyzing the current condition of children's biased eating habits and preference for the unsafe foods. This program was performed for 5 year old children who was attending the kindergarten run by the author every day for two months. "The unsafe food program" consisted of the surveys on the parents' attitude towards food and health and children's eating habits, and of programs that was designed to attract children's attention to their daily food intake and to provide physical fitness, information about differences between wholesome food and junk food, and junk food's bad impacts on human body for children. In order to see the changes of children's body through this program, two physical examinations was preformed: SH pharmaceutical company's hair test to measure the accumulation level of toxic metal in children's hair and children's nutrition level before starting the program, and Ilsan Health Center's 'INBODY' test to analyze children's body composition such as body weight, skeletal muscle mass, body fat mass, BMI, body fat percentage and so on before and after the program. The results from this program follow as below. First, the unsafe foods were excluded from children's diet after parents came to recognize the negative effects of the unsafe foods. Second, children became highly interested in their daily diet through the course of gathering information by themselves and discussions together while testing and analyzing foods, and children demonstrated more self-restraint on fast food and instant food. Third, children's body constitution turned out to be improved by physical fitness in addition to this program. Fourth, children formed a good habit of eating well-balanced diet consisting of vegetables, staple food and fruits through this program designed to improve children's biased eating habits. From the results of this study it was confirmed that "the unsafe food project" had effects on improving children's eating habits.

Managing Technological Risk and Risk Conflict : Public Debates on Health Risks of Mobile Phones EMF (기술위험 관리와 위험갈등 : 휴대전화 전자파의 인체유해성 논란)

  • Jung, Byung-Kul
    • Journal of Science and Technology Studies
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    • v.8 no.1
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    • pp.97-129
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    • 2008
  • We are living in the time of high probability of technological risk due to increased rate of technology development and diffusion of new technologies. Resolving uncertainties, the basic attribution of risk, by accumulating knowledge over the risk factors of certain technology is critical to management of technological risk. In many cases of technological risks, high uncertainty of knowledge is commonly mentioned reason for public controversies on risk management. However, the type of technological risk with low social agreement and low uncertainty of knowledge, the main reason for public controversy is absence of social agreement. Public debates on the risks of mobile phones electromagnetic fields(EMF) to human health comes under this category. The knowledge uncertainty on human health effect of mobile phones EMF has been lowered increasingly by accumulating enormous volume of knowledge though scientists have not reached a final conclusion whether it pose a risk to the physical and mental health of the general population or not. In contrast with civil organizations calling for precautionary approach based regulation, the mobile phone industry is cling to the position of no-regulation-needed by arguing no clear evidence to prove health risks of mobile phone EMF has found. In Korea, government set exposure standards based on a measurement called the 'specific absorption rate'(SAR) and require the mobile phone industry to open SAR information to the public by their own decision. From the view of pro-regulation side based on precautionary approach, technology risk managament of mobile phones EMF in Korea is highly limited and formalized one with limited measuring of SAR on head part only and problematic self-regulated opening of information about SAR to the public. As far as the government keeps having priority on protecting interest of mobile phone industry over precautionary regulation of mobile phones EMF, the disagreement between civil organizations and the government will not resolved. The risk of mobile phones EMF to human health have high probability of being underestimated in the rate and damage of risk than objectively estimated ones due to familiarity of mobile phone technology. And this can be the cause of destructive social dispute or devastating disaster. To prevent such disastrous results, technology risk management, which integrating the goals of safety with economic growth in public policy and designing and promoting risk communication, is required.

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