• Title/Summary/Keyword: Korean dummy

Search Result 541, Processing Time 0.033 seconds

A Comparison of Tiotropium 18㎍, Once Daily and Ipratropium 40㎍, 4 Times Daily in a Double-Blind, Double-Dummy, Efficacy and Safety Study in Adults with Chronic Obstructive Pulmonary Disease (만성폐쇄성폐질환 환자에서 Tiotropium 1일 1회, 1회 18㎍ 요법과 Ipratropium 1일 4회, 1회 40㎍ 요법의 치료효과 및 안전성 비교)

  • Kim, Seung Joon;Kim, Myung Sook;Lee, Sang Haak;Kim, Young Kyoon;Moon, Hwa Sik;Park, Sung Hak;Lee, Sang Yeub;In, Kwang Ho;Lee, Chang Youl;Kim, Young Sam;Kim, Hyung Jung;Ahn, Chul Min;Kim, Sung Kyu;Kim, Kyung Rok;Cha, Seung Ick;Jung, Tae Hoon;Kim, Mi Ok;Park, Sung Soo;Choi, Cheon Woong;Yoo, Jee Hong;Kang, Hong Mo;Koh, Won Jung;Ham, Hyoung Suk;Kang, Eun Hae;Kwon, O Jung;Lee, Yang Deok;Lee, Heung Bum;Lee, Yong Chul;Rhee, Yang Keun;Shin, Won Hyuk;Kwon, Sung Yeon;Kim, Woo Jin;Yoo, Chul Gyu;Kim, Young Whan;Shim, Young Soo;Han, Sung Koo;Park, Hye Kyung;Kim, Yun Seong;Lee, Min Ki;Park, Soon Kew;Kim, Mi Hye;Lee, Won Yeon;Yong, Suk Joong;Shin, Kye Chul;Choi, Byoung Whui;Oh, Yeon Mok;Lim, Chae Man;Lee, Sang Do;Kim, Woo Sung;Kim, Dong Soon;Jung, Sung Soo;Kim, Ju Ock;Ko, Young Chun
    • Tuberculosis and Respiratory Diseases
    • /
    • v.58 no.5
    • /
    • pp.498-506
    • /
    • 2005
  • Background : This study compared the bronchodilator efficacy and safety of tiotropium inhalation capsules ($18{\mu}g$ once daily) with a ipratropium metered dose inhaler (2 puffs of $20{\mu}g$ q.i.d.) in patients with chronic obstructive pulmonary disease (COPD). Method : After the initial screening assessment and a two-week run-in period, patients received either tiotropium $18{\mu}g$ once daily or ipratropium $40{\mu}g$ four times daily over a period of 4 weeks in a double blind, double dummy, parallel group study. The outcome measures were the lung function, the daily records of the peak expiratory flow rate (PEFR), the patients' questionnaire, and the use of concomitant salbutamol. The forced expiratory volume in one second ($FEV_1$) and the forced vital capacity (FVC) were measured 5 minutes before inhalation, and 0.5, 1, 2 and 3 hours after inhaling the study drug on days 0, 14 and 28. Result : In 16 centers, 134 patients with a mean (SD) age of 66 (7) years and a predicted $FEV_1$ of 42 (12)% were analyzed. The trough $FEV_1$ response was significantly higher in the tiotropium group than in the ipratropium group after a four-week treatment period. The weekly mean morning PEFR of the tiotropium group was consistently higher than that of the ipratropium group during the 4-week treatment period with differences ranging from 12.52 to 13.88 l/min, which were statistically significant. Tiotropium was well tolerated by the COPD patients during the 4-week treatment period and had a similar safety profile to ipratropium. Conclusion : This study shows that tiotropium administrated once daily has a superior bronchodilator effect with a similar safety profile in treating COPD patients compared with ipratropium, inhaled four times daily.

Analysis and Satisfaction Survey of Summer Camp Trends of the Education Ministry of Korean Church in the 10th Age of COVID-19 : From 2020 to 2022 (코로나 19시대의 한국교회 교육부 여름 사역 동향 분석 및 만족도 조사 : 2020년부터 2022년까지)

  • Kim, Jaewoo
    • Journal of Christian Education in Korea
    • /
    • v.71
    • /
    • pp.277-303
    • /
    • 2022
  • The COVID-19 Pandemic, which began in 2020, has led to many changes in the Korean church. It created a situation in which not only the change and form of worship time, but also the definition, direction, and philosophy of ministry had to be re-established. In the early days of COVID-19 Pandemic, the Korean church recognized this as a crisis, but gradually regarded these as opportunities and tried to produce positive results. The Department of Education has also undergone many changes, especially in its summer ministry, and is expected to have undergone more dramatic changes in form, location and method than in any other church event or service. However, no accurate data on this has been collected. Accordingly, Mirae with Dreams (CEO: Pastor Kim Eun-ho), a corporation established by the Oryun Church for the next generation of ministry, conducted a survey on the summer ministry of the Korean church, which has been registered as a future member with dreams every year since 2020 when the COVID-19 fan dummy began. A similar survey was conducted in 2022 following 2021, and 260 churches responded, and the results are as follows. In 2022, the summer ministry of the Ministry of Education of the Korean Church returned to the form before the COVID-19 Pandemic. Unlike 2021, when many of them were held online, more than 81 percent said they had conducted summer camps offline, and 31 percent also conducted or attended outdoor camps. In terms of the importance of roles, when online was also the main focus, parents and teachers were equally viewed or emphasized, while in this summer's survey, 90 percent of respondents said that the role of teachers in charge or department was important. Summer events were mainly summer Bible schools and retreats, but 25% of all respondents said they conducted missionary work and evangelism at home and abroad. Compared to 2021, participation in summer camps has increased in all departments, including infant and kindergarten, elementary and middle school, and especially in infant and middle school. While preparing for the summer camp, most of the respondents said that the focus was on content and topics, and the main focus was on children's accessibility compared to 2021. As a result of synthesizing the description of the reason for the respondents who could not conduct the summer camp, about 40% said they could not conduct the summer camp due to a lack of volunteers. This is more than 30% who pointed out COVID-19 as the cause, which can be seen as an urgent problem to be solved at the Korean church and denomination level. In addition, this paper also mentioned detailed changes in each question, referring to the changes in summer camps from 2020 to 2022.

Alcohol Intake in Relation to Cardiovascular Risk Factors among (Middle Age) South Korean Men (한국의 중년기 남성의 심혈관계 질환 위험요인과 음주섭취와의 관련성)

  • Park, Kyung-Min
    • Research in Community and Public Health Nursing
    • /
    • v.9 no.1
    • /
    • pp.232-241
    • /
    • 1998
  • 음주습관과 심혈관계 질환 위험요인사이의 관련성을 파악하기 위하여, 1996년 한국 경북에 있는 도시지역 한 철강회사에서 40-50대(40-59세) 남자 근로자 3444명으로부터 공복시 혈액을 10m1 채취하여 혈청지질, 혈당, Uric acid를 측정하고 신장, 체중, 혈압(10-20분 휴식후 측정)과 EKG를 측정하였다. 과거병력, 현재 건강상태, 음주량과 기간 및 음주종류를 포함한 생활습관, 흡연량/일, 운동시간/주 등의 설문지를 작성하였다. 알콜 소비량은 양-빈도의 Index에 의해 측정되었다. 한국 중년 남자에 대한 음주량, 음주기간, 알콜종류등에 따른 심혈관계 질환의 위험요인 유무 정도를 알아보기 위해, 비음주자를 기준으로하여 비교대상군은 금주자와 음주량(2군) 등에 의해 3군으로 분류하였으며, 음주기간에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주기간(4군)에 따라 5군으로 분류하였다. 알콜종류에 따른 심혈관계 질환의 위험요인 유무정도를 알아보기 위해 비음주자을 기준으로하여 비교 대상군은 금주자와 음주알콜종류(3군)에 따라 4군으로 분류하였다. 심혈관계 질환 위험요인은 기준되는 범주를 2개(Table 1)로 분류하여 2*2표를 이용하여 odds ratio(dummy variable로 처리), ${\beta}$-coefficient와 표준오차를 이용해서 신뢰구간(95% C.I.)을 구하여 유의성 검정을 하였다. 금주자의 정의는 과거 3달 이상 술을 마시지 않는 사람을 말한다. 연구 집단의 평균 연령은 $44.4{\pm}3.9$세 이며, 비음주자는 649명으로 18.9%, 금주자는 70명(2.0%)이며 음주자는 2725명(79.1%)이다. 음주자중 에타놀 섭취를 평균 100.5g/주(median) 미만인 군은 1239명으로 연구집단 3444명중 35.7%이며, 평균 100.5g/주(median) 이상 음주군은 1276명으로 44.5%이었다. 3444명중 1532명(44.5%) 이 맥주와 소주를 섞어서 마시는 사람이었다. 음주 양에서, 연령, 흡연 양, 흡연 기간, 운동, 음주기간, 알콜종류 등을 통제하여 logistic regression한 결과, 비음주자에 비해 중정도 음주자(${\ge}$100.5gm/week ethanol)의 확장기 혈압의 Odds ratio는 1.33배로 유의하게 높았다(P<0.05). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 알콜종류에서도 연령, 흡연 양, 흡연 기간, 운동, 음주양, 음주기간, 등을 통제한, 비음주자에 비해 맥주와 소주를 섞어 마시는 음주자의 확장기 혈압의 Odds ratio는 1.38배로 유의하게 높았다(P<0.01). 다른 요인들은 통계적으로 유의한 차이를 보이지 않았다. 반면에 음주 습관 중 음주기간에서는 연령, 흡연양, 흡연 기간, 운동, 음주양, 알콜종류 등을 통제한 logistic regression 분석 결과 유의한 차이를 보인 것은 없었다. 그러나 음주기간과 심혈관계 질환 위험요인중 수축기와 확장기 혈압과의 관계는 J 모양을 나타내었다 . 수축기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.88) 음주기간이 2-10년인 군의 Odds ratio=1.14, 음주기간이 11-20 년인군의 Odds ratio =1.18, 21년 이상인 군의 Odds ratio=1.20로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다. 확장기 혈압의 금주자군은 비차비가 1.0보다 약간 낮고(Odds ratio=0.91), 음주기간이 1년 이하인 군의 Odds ratio=1.18, 음주기간이 2-10 년인 군의 Odds ratio=1.23, 음주기간이 11-20 년인 군의 Odds ratio=1.27, 21년 이상인 군의 Odds ratio=1.27로 비음주자의 odds ratio=1에 비해 점차적으로 위험이 높아졌다.

  • PDF

Study of the ENC reduction for mobile platform (모바일 플랫폼을 위한 전자해도 소형화 연구)

  • 심우성;박재민;서상현
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
    • /
    • 2003.05a
    • /
    • pp.181-186
    • /
    • 2003
  • The satellite navigation system is widely used for identifying a user's position regardless of weather or geographic conditions and also make effect on new technology of marine LBS(Location Based Service), which has the technology of geographic information such as the ENC. Generally, there are conceivable systems of marine LBS such as ECDIS, or ECS that use the ENC itself with powerful processor in installed type on ships bridge. Since the ENC is relatively heavy structure with dummy format for data transfer between different systems, we should reduce the ENC to small and compact size in order to use it in mobile platform. In this paper, we assumed that the mobile system like PDA, or Webpad can be used for small capability of mobile platform. However, the ENC should be updated periodically by update profile data produced by HO. If we would reduce the ENC without a consideration of update, we could not get newly updated data furthermore. As summary, we studied considerations for ENC reduction with update capability. It will make the ENC be useful in many mobile platforms for various applications.

  • PDF

A Geographically Weighted Regression on the Effect of Regulation of Space Use on the Residential Land Price - Evidence from Jangyu New Town - (공간사용 규제가 택지가격에 미치는 영향에 대한 공간가중회귀분석 - 장유 신도시지역을 대상으로-)

  • Kang, Sun-Duk;Park, Sae-Woon;Jeong, Tae-Yun
    • Management & Information Systems Review
    • /
    • v.37 no.3
    • /
    • pp.27-47
    • /
    • 2018
  • In this study, we examine how land use zoning affects the land price controlling other variables such as road-facing condition of the land, land form, land age after its development and land size. We employ geographically weighted regression analysis which reflects spatial dependency as methodology with a data sample of land transaction price data of Jangyu, a new town, in Korea. The results of our empirical analysis show that the respective coefficients of traditional regression and geographically weighted regression are not significantly different. However, after calculating Moran's Index with residuals of both OLS and GWR models, we find that Moran's Index of GWR decreases around 26% compared to that of OLS model, thus improving the problem of spatial autoregression of residuals considerably. Unlike our expectation, though, in both traditional regression and geographically weighted regression where residential exclusive area is used as a reference variable, the dummy variable of the residential land for both housing and shops shows a negative sign. This may be because the residential land for both housing and shops is usually located in the level area while the residential exclusive area is located at the foot of a mountain or on a gentle hill where the residents can have good quality air and scenery. Although the utility of the residential land for both housing and shops is higher than its counterpart's since it has higher floor area ratio, amenity which can be explained as high quality of air and scenery in this study seems to have higher impact in purchase of land for housing. On the other hand, land for neighbourhood living facility seems to be valued higher than any other land zonings used in this research since it has much higher floor area ratio than the two land zonings above and can have a building with up to 5 stories constructed on it. With regard to road-facing condition, land buyers seem to prefer land which faces a medium-width road as expected. Land facing a wide-width road may have some disadvantage in that it can be exposed to noise and exhaust gas from cars and that entrance may not be easy due to the high speed traffic of the road. In contrast, land facing a narrow road can be free of noise or fume from cars and have privacy protected while it has some inconvenience in that entrance may be blocked by cars parked in both sides of the narrow road. Finally, land age variable shows a negative sign, which means that the price of land declines over time. This may be because decline of the land price of Jangyu was bigger than that of other regions in Gimhae where Jangyu, a new town, also belong, during the global financial crisis of 2008.

Fabrication of Strain Sensor Based on Graphene/Polyurethane Nanoweb and Respiration Measurement (그래핀/폴리우레탄 나노웹 기반의 스트레인센서 제작 및 호흡측정)

  • Lee, Hyocheol;Cho, Hyeon-seon;Lee, Eugene;Jang, Eunji;Cho, Gilsoo
    • Science of Emotion and Sensibility
    • /
    • v.22 no.1
    • /
    • pp.15-22
    • /
    • 2019
  • The purpose of this study is to develop a strain sensor based on a nanoweb by applying electrical conductivity to a polyurethane nanoweb through the use of Graphene. For this purpose, 1% Graphene ink was pour-coated on a polyurethane nanoweb and post-treated with PDMS (Polydimethylsiloxane) to complete a wearable strain sensor. The surface characteristics of the specimens were evaluated using a field emission scanning electron microscope (FE-SEM) to check whether the conductive material was well coated on the surface of the specimen. Electrical properties of the specimens were measured by using a multimeter to measure the linear resistance of the specimen and comparing how the line resistance changes when 5% and 10% of the specimens are tensioned, respectively. In order to evaluate the performance of the specimen, the gauge factor was obtained. The evaluation of the clothing was performed by attaching the completed strain sensor to the dummy and measuring the respiration signal according to the tension using MP150 (Biopac system Inc., USA) and Acqknowledge (ver. 4.2, Biopac system Inc., U.S.A.). As a result of the evaluation of the surface characteristics, it was confirmed that all the conductive nanoweb specimen were uniformly coated with the Graphen ink. As a result of measuring the resistance value according to the tensile strength, the specimen G, which was treated with just graphene had the lowest resistance value, the specimen G-H had the highest resistance value, and the change of the line resistance value of the specimen G and the specimen G-H is increased to 5% It is found that it increases steadily. Unlike the resistance value results, specimen G showed a higher gauge rate than specimen G-H. As a result of evaluation of the actual clothes, the strain sensor made using the specimen G-H measured the stable peak value and obtained a signal of good quality. Therefore, we confirmed that the polyurethane nanoweb treated with Graphene ink plays a role as a breathing sensor.

A Study on the Effect of Social Enterprises Characterics on Financial and Social Performance (사회적기업의 특성이 재무적 성과와 사회적 성과에 미치는 영향: CEO 특성을 중심으로)

  • Hwang, Sooo-Young;Kim, Yong-Duck
    • 한국벤처창업학회:학술대회논문집
    • /
    • 2018.11a
    • /
    • pp.165-175
    • /
    • 2018
  • Since the 1997 financial crisis, large scale unemployment and poverty have become serious, and public and social job creation projects have been carried out. However, with the limitations of low-wage and short-term jobs, the need for long-term and high quality jobs gradually began to attract attention. In recent years, social enterprises have grown both quantitatively and qualitatively and interest in social enterprises has increased. And also it is interested in the determinants of success and failure of social enterprises in the academic field. In this study, we examined the effects of social enterprise characteristics on financial and social performance, and we analyzed empirically by using social enterprises registered in the Korea Social Enterprise Agency. The financial performance of the social enterprise is measured by the net income ratio, operating income ratio, and the return on asset. The social performance of the social enterprise is measured by total number of workers and the employment rate of the vulnerable social groups. The characteristics of the social enterprise include the CEO characteristics (gender, age, experience in operating the social enterprise), the firm size, and the elapsed time of the authentication. The results of the empirical analysis are as follows. First, as a result of analysis for the effect on financial performance, we found that the financial performance have a statistically significant positive relationship with firm size, organizational form, government subsidies and capital adequacy ratio. And it is found that the social performance have a statistically significant negative relationship with CEO age, credit debt dependence. Second, as a result of analysis for the effect on social performance, we foumd that total number of workers have a significant positive relationships with CEO gender, CEO age, and firm size, government subsidies, while total number of workers have a significant negative relationship with certification type and industry dummy. On the other hand, the employment rate of the vulnerable social groups have a siginificant positive relationship with CEO gender and certification type and It have not statistically significant relationship with the government subsidies and the firm size.

  • PDF

The Impact of Social Enterprises on the Financial and Social Performance: An Empirical Analysis in Korea (재무적·사회적 성과를 결정하는 사회적기업의 특성)

  • Hwang, Soo-Young;Kim, Yong-Deok;Koo, Inhyouk
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.14 no.2
    • /
    • pp.61-72
    • /
    • 2019
  • Since the financial crisis in 1997, large scale unemployment and poverty have become serious, but there has been a surge in public and social job creation projects. However, with the limitations of low-wage and short-term jobs, the need for long-term, high quality jobs gradually began to garner attention. In recent years, social enterprises have grown both quantitatively and qualitatively and interest in social enterprises has increased; more specifically, scholars are interested in the determinants of success and failure of social enterprises in the academic field. In this study, we examined the effects of social enterprise characteristics on financial and social performance. In particular, we empirically analyzed social enterprises registered in the Korea Social Enterprise Agency. The financial performance of the social enterprise was measured using the net income ratio, operating income ratio, and the return on asset. The social performance of the social enterprise was measured by the total number of workers and the employment rate of vulnerable social groups. The characteristics of the social enterprise included CEO characteristics (gender, age, experience in operating the social enterprise), firm size, and the elapsed time of authentication. The results of the empirical analysis are as follows. First, as a result of analysis for the effect on financial performance, we found that the financial performance has a statistically significant, positive relationship with firm size, organizational form, government subsidies, and capital adequacy ratio. And we found that the social performance has a statistically significant, negative relationship with CEO age and credit debt dependence. Second, as a result of analysis for the effect on social performance, we found that the total number of workers had a significant, positive relationship with CEO gender and CEO age, as well as firm size, government subsidies; whereas the total number of workers had a significant, negative relationship with certification type and industry dummy. Comparatively, the employment rate of the vulnerable social groups had a significant, positive relationship with CEO gender and certification type, but there was no statistically significant relationship with the government subsidies or firm size.

The association between COVID-19 and changes in food consumption in Korea: analyzing the microdata of household income and expenditure from Statistics Korea 2019-2022 (코로나19와 한국 식품 소비 변화의 관계: 2019-2022년 통계청 소비자 가계동향조사를 활용하여)

  • Haram Eom;Kyounghee Kim;Seonghwan Cho;Junghoon Moon
    • Journal of Nutrition and Health
    • /
    • v.57 no.1
    • /
    • pp.153-169
    • /
    • 2024
  • Purpose: The main goal of this study was to identify the impact of coronavirus disease 2019 (COVID-19) on grocery purchases (i.e., fresh and processed foods by grain, vegetable, fruit, seafood, and meat categories) in Korea. To understand the specific impact of COVID-19, the study period was divided into 3 segments: PRE-COVID-19, INTER-COVID-19, and POST-COVID-19. Methods: We used the microdata of household income and expenditure from Statistics Korea (KOSTAT), representing households across the country. The data comprised monthly grocery expenditure data from January 2019 to September 2022. First, we compared the PRE-COVID-19 period to INTER-COVID-19 and then INTER-COVID-19 to POST-COVID-19 and used multiple regression analysis. The covariates used were the gender and age of the head of the household, the household's monthly income, the number of family members, the price index, and the month (dummy variable). Results: The expenditures on all grocery categories except fresh fruit increased from PRE-COVID-19 to INTER-COVID-19. From INTER-COVID-19 to POST-COVID-19, almost all grocery category spending declined, with processed meat being the only exception. Most purchases of protein sources, increased during INTER-COVID-19 compared to PRE-COVID-19, while ham/sausage/bacon for meat protein, fish cakes and canned seafood for seafood protein, and soy milk for plant-based protein did not decrease during POST-COVID-19 compared to INTER-COVID-19. Conclusion: These results show an overall increase in in-home grocery expenditure during COVID-19 due to an increase in eating at home, followed by a decrease in this expenditure in the POST-COVID-19 period. Among the trends, the protein and highly processed convenience food categories did not see a decline in spending during the POST-COVID-19 period, which is a reflection of the preferences of consumers in the post-COVID-19 period.

APPLICATION OF FUZZY SET THEORY IN SAFEGUARDS

  • Fattah, A.;Nishiwaki, Y.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 1993.06a
    • /
    • pp.1051-1054
    • /
    • 1993
  • The International Atomic Energy Agency's Statute in Article III.A.5 allows it“to establish and administer safeguards designed to ensure that special fissionable and other materials, services, equipment, facilities and information made available by the Agency or at its request or under its supervision or control are not used in such a way as to further any military purpose; and to apply safeguards, at the request of the parties, to any bilateral or multilateral arrangement, or at the request of a State, to any of that State's activities in the field of atomic energy”. Safeguards are essentially a technical means of verifying the fulfilment of political obligations undertaken by States and given a legal force in international agreements relating to the peaceful uses of nuclear energy. The main political objectives are: to assure the international community that States are complying with their non-proliferation and other peaceful undertakings; and to deter (a) the diversion of afeguarded nuclear materials to the production of nuclear explosives or for military purposes and (b) the misuse of safeguarded facilities with the aim of producing unsafeguarded nuclear material. It is clear that no international safeguards system can physically prevent diversion. The IAEA safeguards system is basically a verification measure designed to provide assurance in those cases in which diversion has not occurred. Verification is accomplished by two basic means: material accountancy and containment and surveillance measures. Nuclear material accountancy is the fundamental IAEA safeguards mechanism, while containment and surveillance serve as important complementary measures. Material accountancy refers to a collection of measurements and other determinations which enable the State and the Agency to maintain a current picture of the location and movement of nuclear material into and out of material balance areas, i. e. areas where all material entering or leaving is measurab e. A containment measure is one that is designed by taking advantage of structural characteristics, such as containers, tanks or pipes, etc. To establish the physical integrity of an area or item by preventing the undetected movement of nuclear material or equipment. Such measures involve the application of tamper-indicating or surveillance devices. Surveillance refers to both human and instrumental observation aimed at indicating the movement of nuclear material. The verification process consists of three over-lapping elements: (a) Provision by the State of information such as - design information describing nuclear installations; - accounting reports listing nuclear material inventories, receipts and shipments; - documents amplifying and clarifying reports, as applicable; - notification of international transfers of nuclear material. (b) Collection by the IAEA of information through inspection activities such as - verification of design information - examination of records and repo ts - measurement of nuclear material - examination of containment and surveillance measures - follow-up activities in case of unusual findings. (c) Evaluation of the information provided by the State and of that collected by inspectors to determine the completeness, accuracy and validity of the information provided by the State and to resolve any anomalies and discrepancies. To design an effective verification system, one must identify possible ways and means by which nuclear material could be diverted from peaceful uses, including means to conceal such diversions. These theoretical ways and means, which have become known as diversion strategies, are used as one of the basic inputs for the development of safeguards procedures, equipment and instrumentation. For analysis of implementation strategy purposes, it is assumed that non-compliance cannot be excluded a priori and that consequently there is a low but non-zero probability that a diversion could be attempted in all safeguards ituations. An important element of diversion strategies is the identification of various possible diversion paths; the amount, type and location of nuclear material involved, the physical route and conversion of the material that may take place, rate of removal and concealment methods, as appropriate. With regard to the physical route and conversion of nuclear material the following main categories may be considered: - unreported removal of nuclear material from an installation or during transit - unreported introduction of nuclear material into an installation - unreported transfer of nuclear material from one material balance area to another - unreported production of nuclear material, e. g. enrichment of uranium or production of plutonium - undeclared uses of the material within the installation. With respect to the amount of nuclear material that might be diverted in a given time (the diversion rate), the continuum between the following two limiting cases is cons dered: - one significant quantity or more in a short time, often known as abrupt diversion; and - one significant quantity or more per year, for example, by accumulation of smaller amounts each time to add up to a significant quantity over a period of one year, often called protracted diversion. Concealment methods may include: - restriction of access of inspectors - falsification of records, reports and other material balance areas - replacement of nuclear material, e. g. use of dummy objects - falsification of measurements or of their evaluation - interference with IAEA installed equipment.As a result of diversion and its concealment or other actions, anomalies will occur. All reasonable diversion routes, scenarios/strategies and concealment methods have to be taken into account in designing safeguards implementation strategies so as to provide sufficient opportunities for the IAEA to observe such anomalies. The safeguards approach for each facility will make a different use of these procedures, equipment and instrumentation according to the various diversion strategies which could be applicable to that facility and according to the detection and inspection goals which are applied. Postulated pathways sets of scenarios comprise those elements of diversion strategies which might be carried out at a facility or across a State's fuel cycle with declared or undeclared activities. All such factors, however, contain a degree of fuzziness that need a human judgment to make the ultimate conclusion that all material is being used for peaceful purposes. Safeguards has been traditionally based on verification of declared material and facilities using material accountancy as a fundamental measure. The strength of material accountancy is based on the fact that it allows to detect any diversion independent of the diversion route taken. Material accountancy detects a diversion after it actually happened and thus is powerless to physically prevent it and can only deter by the risk of early detection any contemplation by State authorities to carry out a diversion. Recently the IAEA has been faced with new challenges. To deal with these, various measures are being reconsidered to strengthen the safeguards system such as enhanced assessment of the completeness of the State's initial declaration of nuclear material and installations under its jurisdiction enhanced monitoring and analysis of open information and analysis of open information that may indicate inconsistencies with the State's safeguards obligations. Precise information vital for such enhanced assessments and analyses is normally not available or, if available, difficult and expensive collection of information would be necessary. Above all, realistic appraisal of truth needs sound human judgment.

  • PDF