• Title/Summary/Keyword: External Exposure Characteristics

Search Result 53, Processing Time 0.031 seconds

Development of a Monte Carlo Simulation Code (CALEFF) for Calibrating Thyroid Internal Dose Measurement and Detection Efficiency Calculation (갑상선 내부피폭선량 측정치 보정을 위한 몬테카를로 모의실험 코드 (CALEFF) 개발 및 검출효율 계산)

  • Ahn, Ki-Soo;Cho1, Hyo-Sung
    • Journal of radiological science and technology
    • /
    • v.28 no.2
    • /
    • pp.117-122
    • /
    • 2005
  • According to the Para. 5 of Art 2 of the Korean Nuclear Safety Regulations, which was revised in 1999, internal dose assessment as well as external one should be performed by law for employees at a nuclear power plant from 2003, and their estimate errors should also be within 50%. Thus, more accurate internal dosimetry becomes important. Corresponding to such regulation revision, we are developing a more accurate thyroid-uptake internal dosimetric system and have developed a Monte Carlo simulation code, the so-called CALEFF, to calculate the detection efficiency of the dosimetric system. In this paper, we calculated detection efficiencies with various test conditions by using the CALEFF code and discussed their characteristics. We may use the detection efficiency calculated by the code in calibrating the thyroid internal dose from measured data.

  • PDF

Intercomparison Exercise at Harshaw 6600, DVG-02TM, and D-Shuttle Dosimeters for the Individual Monitoring of Ionizing Radiation

  • Kim, Dmitriy Spartakovich;Murayama, Kentaro;Nurtazin, Yernat;Koguchi, Yasuhiro;Kenzhin, Yergazy;Kawamura, Hiroshi
    • Journal of Radiation Protection and Research
    • /
    • v.44 no.2
    • /
    • pp.79-88
    • /
    • 2019
  • Background: The main goal of experiments is to compare various operational and technical characteristics of D-Shuttle semiconductor personal dosimeters of the Japanese company "Chiyoda Technol Corporation" and Harshaw thermoluminescent dosimeters (TLD) manufactured by "Thermo Fisher Scientific" and DTL-02 of the Russian Research and Production Enterprise (RPE) "Doza" by their occupational and calibration exposure at various dose equivalents from 0.5 to 20 mSv of gamma-radiation. Materials and Methods: Besides dosimeters DTL-02, D-Shuttle and Harshaw TLD, there were also used: (1) the primary reference radionuclide source Hopewell Designs IAEA: G10-1-12 with $^{137}Cs$ isotope (an error is not more than 6% and activity is 20 Ci), and (2) the verification device UPGD-2M of RPE "Doza" and installed in the National Center for Expertise and Certification of the Republic of Kazakhstan (Kapchagai, the National Center for Expertise and Certification). Results and Discussion: The main results of researches are the following: (1) TLDs for Harshaw 6600 and DVG-02TM have an approximately equal measurement accuracy of the individual dose equivalents in the range from 0.5 to 20 mSv of gamma-radiation. (2) Advantages of dosimeters for Harshaw 6600 are due to the high measurement productivity and opportunity to indicate the dose on the skin $H_p$(0.07). Advantages of DVG-02TM consist of operation simplicity and lower cost than of Harshaw 6600. (3) D-Shuttles are convenient for use in the current and the operational monitoring of ionizing radiation. Measurement accuracy and 10% linearity of measurements are ensured when D-Shuttle is irradiated with dose equivalents below 1 mSv at the equivalent dose rate not higher than $3mSv{\cdot}hr^{-1}$. This allows using D-Shuttle at a routine technological activity. Conclusion: The obtained results of experiments demonstrate advantages and disadvantages of D-Shuttle semiconductor dosimeters in comparison with two TLD systems of DVG-02TM and Harshaw 6600.

A Review on the Hazards of Flavoring Chemicals in Coffee Roasting Proces (커피 로스팅 공정에서 발생되는 향기물질의 유해성 고찰 및 노동자 건강보호 방안)

  • Rim, Kyung-Taek
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.29 no.2
    • /
    • pp.119-140
    • /
    • 2019
  • Objectives: This study was based on the occurrence of a coffee roasting process-related disorder(bronchiolitis obliterans; published by NIOSH in the US) among workers exposed to chemicals called diacetyl in a coffee processing facility. Flavorings added to coffee contain diacetyl and 2,3-pentanedione, all of which are subject to exposure in a number of food manufacturing processes, including coffee roasting, grinding, and packaging. Therefore, this study aims to review the toxicity to workers related to food processing and food additive manufacturing to prevent occupational diseases. Methods: We surveyed the related literature, domestic and international references, and the status of relevant domestic and foreign professional organizations. The present situation of workers was investigated by reviewing literature on the safety and health of workers in the coffee roasting process using domestic and foreign literature and presentations. Expert advisory opinions were reflected, and experts were consulted by participating in domestic and overseas academic conferences. Results: Most of the fragrance materials for coffee were harmful and hazardous substances according to the GHS classification, and research was carried out through a second external consultation. A literature review on the measurement of air pollutant emissions from coffee roasters and the estimation of air pollutant emissions during coffee roasting examined the characteristics of pollutants emitted during coffee roasting. Conclusions: Two chemicals identified as causing bronchiolitis obliterans in the coffee roasting process are believed to explain why the disease is difficult to treat. This information can be used effectively in the future prevention of this disease. Future studies should clearly identify the potential for toxicity of alpha-diketones and the bases of OELs in relation to the occurrence of obstructive bronchiolitis, including measurement of various organic compounds and alpha-diketones from ground coffee, as well as various coffee grinds and coffee bean varieties. In particular, it is necessary to clarify the current understanding of the dose-response relationship between alpha-diketone and lung disease in workers involved in coffee roasting.

Clinical Characteristics of Trauma-Related Chronic Osteomyelitis in 3 Wild Raccoon Dogs (Nyctereutes procyonoides)

  • Ha, Minjong;Ahmed, Sohail;Lee, Do Na;Han, Janghee;Yoon, Junghee;Yeon, Seong-Chan
    • Journal of Veterinary Clinics
    • /
    • v.39 no.3
    • /
    • pp.131-137
    • /
    • 2022
  • Osteomyelitis typically occurs because of the direct inoculation of bacteria or fungi after penetrating trauma or surgical contamination or, by extension, from soft tissue infection. Osteomyelitis is rarely reported in wildlife animals, though severe chronic osteomyelitis cases do exist in wildlife owing to the scarcity of medical support in the wild environment. This report describes three cases of chronic osteomyelitis in wild raccoon dogs related to trauma. The typical symptoms of three reported cases were ataxia, stiffness, muscle atrophy, and lethargy. All three cases were relevant to traumatic or severe external injury, and skin infestation caused by ectoparasites was apparent on an ocular inspection. In the radiographic examination, diffuse sites of osteolytic lesions and remarkable periosteal responses were demonstrated around the injured limb in all three cases. Apparent neutrophilia with a left shift, lymphocytosis, and monocytosis in hematological examinations generally indicated chronic infection as shown in case 1 and 3. Treatment was attempted with broad-spectrum antibiotics and non-steroidal anti-inflammatory drugs, such as amoxicillin/clavulanic acid, enrofloxacin, clindamycin, and meloxicam. These treatment options helped improve the overall prognosis of chronic osteomyelitis, but the outcomes did not meet the treatment goal entirely. Osteomyelitis can be extremely challenging to treat, particularly in wild animals, because of their distinctive traits, such as masking phenomenon and uncontrolled exposure to ectoparasites. Earlier diagnosis with a radiographic examination, hematological examinations, and careful patient monitoring, followed by prolonged antibiotic therapy and restricted exercise, are the key factors leading to a better prognosis.

The necessary & method of scrotoplasty in female to male transgender (여성에서 남성으로의 성전환증에서 음낭성형술의 필요성과 방법)

  • Kim, Seok-Kwun;Moon, In-Sun;Kwon, Yong-Seok;Lee, Keun-Cheol
    • Archives of Plastic Surgery
    • /
    • v.36 no.4
    • /
    • pp.437-444
    • /
    • 2009
  • Purpose: Transgender is a disorder of gender identity, who have appropriate chromosomal, hormonal and anatomical characteristics corresponding to their sexual phenotype but feel strongly with respect to their sexual identity, that they belong to the opposite sex. There is a persistence discomfort and sense of inappropriateness about one's assigned sex in a person who has reached puberty. Transgender is a psychiatric problem, but surgical method provides more satisfactory adjustment for patients. In gender reassignment surgery for female to male transgender, mastectomy, nipple reduction, hysterectomy, oophorectomy and phalloplasty are included. And as the final operation, recommended for scrotoplasty and artificial testes insertion. So we investigated the necessity and method of scrotoplasty in the final operation of female to male transgender. Method: The authors have long term follow-up of 75 cases female to male transgender during January, 1991 to February, 2008. Among them, 13 cases were evaluated in this study. During phalloplasty, the labium major skin preserved. And this labium majoral skin flap was made for the neoscrotum. At least six months later, artificial testes were inserted in neoscrotum with local anesthesia. Middle sized (3 cm diameter) artificial testes(silicon gel or carving soft silicone implant) were used because of the limitation of the neoscrotum. We evaluated the questionnaire and interview about the postoperative satisfaction in configuration of reconstructed scrotum, and the necessity of operation, the postoperative psychosocioeconomic improvement and limitation of body exposure activities such as swimming, public bathing. Results: Based on this study, satisfaction of reconstructed scrotum after scrotoplasty was improved(92%). The necessity of scrotoplasty was in 92.3% and the postoperative psychosocioeconomic well - being improvement was 77% in answers. Less limitation of activities requiring body exposure was 54% in answers. Most of the patients were satisfied with the results of surgical operation inspite of the operative procedure had some postoperative complications. Conclusion: This study was reported that the scrotoplasty in female to male transgender is not only a conversion of external genitalia but also an improvement of psychosocial state. Most patients sincerely hope to this operation, so we improve our surgical method for more good results.

The Influence of Ethical Leadership and Collaborative Communication on IS Behavior in Organizations: The Role of Trust and Person-Organization Fit (조직 내 정보보안 행동 관련 윤리적 리더십과 협력적 커뮤니케이션의 영향: 신뢰 및 개인-조직 적합성 역할)

  • In-Ho Hwang
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.18 no.3
    • /
    • pp.465-474
    • /
    • 2023
  • As the effective use and strong protection of an organization's information resources are recognized as a condition for the growth of an organization, they are increasing technological and policy investments in IS(information security). However, information exposure can occur from external invasions such as hacking and incidents related to misuse and abuse by insiders. This study proposes a mechanism that considers the organizational environment and individual characteristics from the viewpoint of promoting employees' IS participation activities. In other words, the study presents the complex effects of organizational environmental factors (ethical leadership, IS collaborative communication) and personal factors (person-organization fit) on organization trust and IS voice behavior. We surveyed office workers who asked for IS-related business activities and tested hypotheses using 422 samples. As a result, ethical leadership influenced organization trust through collaborative communication, and organization trust strengthened IS voice behavior by having an interaction effect with person-organization fit. This study suggests direction for establishing an organizational environment for promoting IS-related activities by office workers, so it provides practical implications for organizations with goals related to internal information exposure control.

Assessment of Internal Radiation Dose Due to Inhalation of Particles by Workers in Coal-Fired Power Plants in Korea (국내 석탄화력발전소 내 작업종사자의 입자 흡입에 따른 내부피폭 방사선량 평가)

  • Do Yeon Lee;Yong Ho Jin;Min Woo Kwak;Ji Woo Kim;Kwang Pyo Kim
    • Journal of Radiation Industry
    • /
    • v.17 no.2
    • /
    • pp.161-172
    • /
    • 2023
  • Coal-fired power plants handle large quantities of coal, one of the most prominent NORM, and the coal ash produced after the coal is burned can be tens of times more radioactive than the coal. Workers in these industries may be exposed to internal exposure by inhalation of particles while handling NORM. This study evaluated the size, concentration, particle shape and density, and radioactivity concentrations of airborne suspended particles in the main processes of a coal-fired power plant. Finally, the internal radiation dose to workers from particle inhalation was evaluated. For this purpose, airborne particles were collected by size using a multi-stage particle collector to determine the size, shape, and concentration of particles. Samples of coal and coal ash were collected to measure the density and radioactivity of particles. The dose conversion factor and annual radionuclide inhalation amount were derived based on the characteristics of the particles. Finally, the internal radiation dose due to particle inhalation was evaluated. Overall, the internal radiation dose to workers in the main processes of coalfired power plants A and B ranged from 1.47×10-5~1.12×10-3 mSv y-1. Due to the effect of dust generated during loading operations, the internal radiation dose of fly ash loading processes in both coal-fired power plants A and B was higher than that of other processes. In the case of workers in the coal storage yard at power plants A and B, the characteristic values such as particle size, airborne concentration, and working time were the same, but due to the difference in radioactivity concentration and density depending on the origin of the coal, the internal radiation dose by origin was different, and the highest was found when inhaling coal imported from Australia among the five origins. In addition, the main nuclide contributing the most to the internal radiation dose from the main processes in the coal-fired power plants was thorium due to differences in dose conversion factors. However, considering the external radiation dose of workers in coal-fired power plants presented in overseas research cases, the annual effective dose of workers in the main processes of power plants A and B does not exceed 1mSv y-1, which is the dose limit for the general public notified by the Nuclear Safety Act. The results of this study can be utilized to identify the internal exposure levels of workers in domestic coal-fired power plants and will contribute to the establishment of a data base for a differential safety management system for NORM-handling industries in the future.

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
    • /
    • v.59 no.2
    • /
    • pp.5-38
    • /
    • 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.

  • PDF

The Effect of Barrel Vibration Intensity to the Plating Thickness Distribution

  • Lee, Jun-Ho;Roselle D. Llido
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 1999.10a
    • /
    • pp.15-15
    • /
    • 1999
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

  • PDF

Aesthetic Rhinoplasty for the Improvement of the Lateral Facial Profile; Image-up Rhinoplasty (얼굴의 측면 윤곽선 개선을 위한 미용 코성형술)

  • Min Sung
    • Archives of Plastic Surgery
    • /
    • v.32 no.2
    • /
    • pp.205-213
    • /
    • 2005
  • There are several characteristics of the nose of orientals. The dorsum of nose is flat and low, the skin is thick with severe tension, the nasal tip is bulbous, the nostril is wide, and the projection of the nose is limited due to a poorly developed alar cartilage with a short columella. In order to improve these untoward characteristics of the nose of Orientals aesthetically, plain augmentation of the dorsum and tip-plasty with conventional methods has been performed by many plastic surgeons. However these conventional rhinoplasty is not enough to obtain satisfactory results when transforming into a more beautiful and aesthetically charming appearance. In order to produce the optimal nasal shape and profile, it is extremely important to consider the aesthetic surgical factors, which are; the position of the nasion, the optimal nasolabial angle(95-100 degree in Orientals), the natural exposure of infra-tip lobule with and columella, the position of the tip defining point in harmony with the dorsal profile and the smooth and natural silhouette of the lateral nasal profile as it descends into the inferior portion of the nose. From April, 2003 to August, 2004, a total of 52 patients underwent open rhinoplasty, adhering to the strict aesthetic principles considered and described priorly. Surgical approach was done through a transcolumella incision and an alar rim incision. The nasal dorsum was augmented with a silicone implant and the shape of the columella and the nasolabial angle were finessed with a silicone strut implant which was placed in between the medial crurae in a manner of a non-visible graft. The nasal tip was corrected by alar cartilage suture technique and onlay graft of shield shaped Alloderm and Gore-Tex. Author obtained the optimal nasal shape and profile aesthetically, and the results, considered satisfactory in all patients without any complications, are as follows; 1. the average increase in nasal length was 2.5 mm, 2. the average decrease in nasal width was 2.1 mm, 3. the average increase in nasal tip projection was 3.2 mm, 4. the changes of nasolabial angles were from 85.5 degree to 94.7 degree, 5. the changes of the angle between the long axis of the external naris was from 101.3 degree to 89.5 degree. In conclusion, this surgical procedure is an effective, reliable and a valuable method in improving the nasal shape, tip projection, nasolabial angle and especially, the lateral facial profile of Orientals aesthetically.