• Journal of Food Hygiene and Safety
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• v.38 no.6
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• pp.420-429
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• 2023

GC-MS/MS using liquid-liquid extraction (LLE) and C18 cartridges was used to identify and quantify levels of chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin and permethrin in bulk raw milk. A calibration curve spanning 10 ng/mL to 200 ng/mL was obtained with a satisfactory correlation coefficient of 0.99. The limits of detection (LOD) and limits of quantitation (LOQ) for chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin, and permethrin in the matrix ranged from 0.06 to 1.81 ng/mL and 0.19 to 6.04 ng/mL, respectively. The recoveries of 5 pesticides from spiked samples at 37.5-125 ng/mL ranged from 86.1 to 102.1%. The measurement of uncertainty of the GC-MS/MS method for these five pesticides was developed based on the analytical process and quantification. An analysis method that is easier and faster than the method specified in the Korean food standards codes for analyzing these five pesticides in raw material milk was developed. Moreover, the analytical method for chlorpyrifos, chlorpyrifos-methyl, cypermethrin, deltamethrin, and permethrin in bulk raw milk by GC-MS/MS was established.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.1 no.1
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• pp.21-32
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• 1981

Recent trends in design standards development in some European countries and U.S.A. have encouraged the use of probabilistic limit sate design concepts. Reliability based design criteria such as LSD, LRFD, PBLSD, adopted in those advanced countries have the potentials that they afford for symplifying the design process and placing it on a consistent reliability bases for various construction materials. A reliability based design criteria for RC flexural members are proposed in this study. Lind-Hasofer's invariant second-moment reliability theory is used in the derivation of an algorithmic reliability analysis method as well as an iterative determination of load and resistance factors. In addition, Cornell's Mean First-Order Second Moment Method is employed as a practical tool for the approximate reliability analysis and the derivation of design criteria. Uncertainty measures for flexural resistance and load effects are based on the Ellingwood's approach for the evaluation of uncertainties of loads and resistances. The implied relative safety levels of RC flexural members designed by the strength design provisions of the current standard code were evaluated using the second moment reliability analysis method proposed in this study. And then, resistance and load factors corresponding to the target reliability index(${\beta}=4$) which is considered to be appropriate level of reliability considering our practices are calculated by using the proposed methods. These reliability based factors were compared to those specified by our current ultimate strength design provisions. It was found that the reliability levels of flexural members designed by current code are not appropriate, and the code specified resistance and load factors were considerably different from the reliability based resistance and load factors proposed in this study.

• Korean Journal of Ecology and Environment
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• v.38 no.2 s.112
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• pp.225-236
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• 2005

The protection of public health In wastewater reclamation and reuse is one of the most important issues. Monitoring data of Escherichia coli were collected from paddy rice plots in 2003 and 2004 experiments. Five treatments were used and each one was triplicated to evaluate the changes of E. coli: surface water, biofilter effluent (secondary level), UV-disinfected water and pond treatment. Microbial risk was quantified to assess human health risk by exposure to E. coli in paddy rice plots, which were irrigated with reclaimed wastewater. Beta-Poisson model was used to estimate the microbial risk of pathogen ingestion that may occur to farmer and neighbor children. Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. In the following analysis, two scenarios were related to the reduction of risk against direct ingestion and exposure times. Scenarios A and B were assumed that the risk was 1,000 and 10,000 times lower than direct ingestion.'Golfers were assumed to be 0.001 L of reclaimed water by contact with balls and their cloths. Opportunity of contact in paddy rice field with pathogens was more frequent than handing golf balls, because of agricultural activity was practiced in ponded water in paddy rice culture. As a result of microbial risk assessment using total data of experimental period, risk value of E. coli in 2003 and 2004 experiment ranged from $10^{-5}$ to $10^{-8}$ and $10^{-4}$ to $10^{-8}$, respectively. The risk values in biofilter effluent irrigation was the highest, which is $10^{-4}$ in 2003 and $10^{-5}$ in 2004 experiments with scenario A. Ranges of $10^{-6}$ to $10^{-8}$ were considered at reasonable levels of risk for communicable disease transmission from environmental exposure and the risk value above $10^{-4}$ was considered to be attributable to the risk of infection. Irrigation with UV-disinfected water in the paddy field during the agricultural Period showed significantly lower microbial risk than others, and their levels of risk value were within the range of actual paddy rice field with surface water.

• Asia Marketing Journal
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• v.15 no.4
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• pp.61-101
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• 2014

This study investigates when and how disagreements in online customer ratings prompt more favorable product evaluations. Among the three metrics of volume, valence, and variance that feature in the research on online customer ratings, volume and valence have exhibited consistently positive patterns in their effects on product sales or evaluations (e.g., Dellarocas, Zhang, and Awad 2007; Liu 2006). Ratings variance, or the degree of disagreement among reviewers, however, has shown rather mixed results, with some studies reporting positive effects on product sales (e.g., Clement, Proppe, and Rott 2007) while others finding negative effects on product evaluations (e.g., Zhu and Zhang 2010). This study aims to resolve these contradictory findings by introducing preference heterogeneity as a possible moderator and causal attribution as a mediator to account for the moderating effect. The main proposition of this study is that when preference heterogeneity is perceived as high, a disagreement in ratings is attributed more to reviewers' different preferences than to unreliable product quality, which in turn prompts better quality evaluations of a product. Because disagreements mostly result from differences in reviewers' tastes or the low reliability of a product's quality (Mizerski 1982; Sen and Lerman 2007), a greater level of attribution to reviewer tastes can mitigate the negative effect of disagreement on product evaluations. Specifically, if consumers infer that reviewers' heterogeneous preferences result in subjectively different experiences and thereby highly diverse ratings, they would not disregard the overall quality of a product. However, if consumers infer that reviewers' preferences are quite homogeneous and thus the low reliability of the product quality contributes to such disagreements, they would discount the overall product quality. Therefore, consumers would respond more favorably to disagreements in ratings when preference heterogeneity is perceived as high rather than low. This study furthermore extends this prediction to the various levels of average ratings. The heuristicsystematic processing model so far indicates that the engagement in effortful systematic processing occurs only when sufficient motivation is present (Hann et al. 2007; Maheswaran and Chaiken 1991; Martin and Davies 1998). One of the key factors affecting this motivation is the aspiration level of the decision maker. Only under conditions that meet or exceed his aspiration level does he tend to engage in systematic processing (Patzelt and Shepherd 2008; Stephanous and Sage 1987). Therefore, systematic causal attribution processing regarding ratings variance is likely more activated when the average rating is high enough to meet the aspiration level than when it is too low to meet it. Considering that the interaction between ratings variance and preference heterogeneity occurs through the mediation of causal attribution, this greater activation of causal attribution in high versus low average ratings would lead to more pronounced interaction between ratings variance and preference heterogeneity in high versus low average ratings. Overall, this study proposes that the interaction between ratings variance and preference heterogeneity is more pronounced when the average rating is high as compared to when it is low. Two laboratory studies lend support to these predictions. Study 1 reveals that participants exposed to a high-preference heterogeneity book title (i.e., a novel) attributed disagreement in ratings more to reviewers' tastes, and thereby more favorably evaluated books with such ratings, compared to those exposed to a low-preference heterogeneity title (i.e., an English listening practice book). Study 2 then extended these findings to the various levels of average ratings and found that this greater preference for disagreement options under high preference heterogeneity is more pronounced when the average rating is high compared to when it is low. This study makes an important theoretical contribution to the online customer ratings literature by showing that preference heterogeneity serves as a key moderator of the effect of ratings variance on product evaluations and that causal attribution acts as a mediator of this moderation effect. A more comprehensive picture of the interplay among ratings variance, preference heterogeneity, and average ratings is also provided by revealing that the interaction between ratings variance and preference heterogeneity varies as a function of the average rating. In addition, this work provides some significant managerial implications for marketers in terms of how they manage word of mouth. Because a lack of consensus creates some uncertainty and anxiety over the given information, consumers experience a psychological burden regarding their choice of a product when ratings show disagreement. The results of this study offer a way to address this problem. By explicitly clarifying that there are many more differences in tastes among reviewers than expected, marketers can allow consumers to speculate that differing tastes of reviewers rather than an uncertain or poor product quality contribute to such conflicts in ratings. Thus, when fierce disagreements are observed in the WOM arena, marketers are advised to communicate to consumers that diverse, rather than uniform, tastes govern reviews and evaluations of products.

• Journal of Global Scholars of Marketing Science
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• v.17 no.4
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• pp.247-269
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• 2007

In recent years, one of the major reasons for the fierce competition amongst firms is that they strive to increase their own market shares and customer acquisition rate in the same market with similar and apparently undifferentiated products in terms of quality and perceived benefit. Because of this change in recent marketing environment, the differentiated after-sales service and diversified promotion strategies have become more important to gain competitive advantage. Price promotion is the favorite strategy that most retailers use to achieve short-term sales increase, induce consumer's brand switch, in troduce new product into market, and so forth. However, if marketers apply or copy an identical price promotion strategy without considering the characteristic differences in product and consumer preference, it will cause serious problems because discounted price itself could make people skeptical about product quality, and the changes of perceived value might appear differently depending on other factors such as consumer involvement or brand attitude. Previous studies showed that price promotion would certainly increase sales, and the discounted price compared to regular price would enhance the consumer's perceived values. On the other hand, discounted price itself could make people depreciate or skeptical about product quality, and reduce the consumers' positivity bias because consumers might be unsure whether the current price promotion is the retailer's best price offer. Moreover, we cannot say that discounted price absolutely enhances the consumer's perceived values regardless of product category and purchase situations. That is, the factors that affect consumers' value perceptions and buying behavior are so diverse in reality that the results of studies on the same dependent variable come out differently depending on what variable was used or how experiment conditions were designed. Majority of previous researches on the effect of price-comparison advertising have used consumers' buying behavior as dependent variable. In order to figure out consumers' buying behavior theoretically, analysis of value perceptions which influence buying intentions is needed. In addition, they did not combined the independent variables such as brand loyalty and price discount rate together. For this reason, this paper tried to examine the moderating effect of brand loyalty on relationship between the different levels of discounting rate and buyers' value perception. And we provided with theoretical and managerial implications that marketers need to consider such variables as product attributes, brand loyalty, and consumer involvement at the same time, and then establish a differentiated pricing strategy case by case in order to enhance consumer's perceived values properl. Three research concepts were used in our study and each concept based on past researches was defined. The perceived acquisition value in this study was defined as the perceived net gains associated with the products or services acquired. That is, the perceived acquisition value of the product will be positively influenced by the benefits buyers believe they are getting by acquiring and using the product, and negatively influenced by the money given up to acquire the product. And the perceived transaction value was defined as the perception of psychological satisfaction or pleasure obtained from taking advantage of the financial terms of the price deal. Lastly, the brand loyalty was defined as favorable attitude towards a purchased product. Thus, a consumer loyal to a brand has an emotional attachment to the brand or firm. Repeat purchasers continue to buy the same brand even though they do not have an emotional attachment to it. We assumed that if the degree of brand loyalty is high, the perceived acquisition value and the perceived transaction value will increase when higher discount rate is provided. But we found that there are no significant differences in values between two different discount rates as a result of empirical analysis. It means that price reduction did not affect consumer's brand choice significantly because the perceived sacrifice decreased only a little, and customers are satisfied with product's benefits when brand loyalty is high. From the result, we confirmed that consumers with high degree of brand loyalty to a specific product are less sensitive to price change. Thus, using price promotion strategy to merely expect sale increase is not recommendable. Instead of discounting price, marketers need to strengthen consumers' brand loyalty and maintain the skimming strategy. On the contrary, when the degree of brand loyalty is low, the perceived acquisition value and the perceived transaction value decreased significantly when higher discount rate is provided. Generally brands that are considered inferior might be able to draw attention away from the quality of the product by making consumers focus more on the sacrifice component of price. But considering the fact that consumers with low degree of brand loyalty are known to be unsatisfied with product's benefits and have relatively negative brand attitude, bigger price reduction offered in experiment condition of this paper made consumers depreciate product's quality and benefit more and more, and consumer's psychological perceived sacrifice increased while perceived values decreased accordingly. We infer that, in the case of inferior brand, a drastic price-cut or frequent price promotion may increase consumers' uncertainty about overall components of product. Therefore, it appears that reinforcing the augmented product such as after-sale service, delivery and giving credit which is one of the levels consisting of product would be more effective in reality. This will be better rather than competing with product that holds high brand loyalty by reducing sale price. Although this study tried to examine the moderating effect of brand loyalty on relationship between the different levels of discounting rate and buyers' value perception, there are several limitations. This study was conducted in controlled conditions where the high involvement product and two different levels of discount rate were applied. Given the presence of low involvement product, when both pieces of information are available, it is likely that the results we have reported here may have been different. Thus, this research results explain only the specific situation. Second, the sample selected in this study was university students in their twenties, so we cannot say that the results are firmly effective to all generations. Future research that manipulates the level of discount along with the consumer involvement might lead to a more robust understanding of the effects various discount rate. And, we used a cellular phone as a product stimulus, so it would be very interesting to analyze the result when the product stimulus is an intangible product such as service. It could be also valuable to analyze whether the change of perceived value affects consumers' final buying behavior positively or negatively.

• Journal of Global Scholars of Marketing Science
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• v.20 no.2
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• pp.208-218
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• 2010

Internet has grown fast and become one of the most important retail channels now. Various types of Internet retailers, hereafter etailers, have been introduced so far and as one type of Internet shopping mall, 'surrogate Internet shopping mall' has been prosperous and attracting consumers in the domestic market. Surrogate Internet shopping mall is a unique type of etailer that globally purchases well-known brand goods that are not imported in the market, completes delivery in the favor of individual buyers, and collects fees for these specific services. The consumers, who are usually interested in purchasing high-end and unique but not eligible brands, have difficulties to purchase these items overseas directly from the retailers or brands in other countries due to worries of payment failure and no address available for their usually domestic only delivery. In Korea, both numbers of surrogate Internet shopping malls and the magnitude of sales have been growing rapidly up to more than 430 active malls and 500 billion Korean won in 2008 since the population of consumers who want this agent shopping service is also expending. This etail business concept is originated from 'surrogate-mediated purchase' and this type of shopping agent has existed in many different forms and also in wide ranges of context level for quite a long time. As marketers face their individual buyers' representatives instead of a direct contact with them in many occasions, the impact of surrogate shoppers on consumer's decision making has been enormously important and many scholars have explored various range of agent's impact on consumer's purchase decisions in marketing and psychology field. However, not much rigorous research in the Internet commerce has been conveyed yet. Moreover, since as one of the shopping agent surrogate Internet shopping malls specifically connect overseas brands or retailers to domestic consumers, one specific character of the mall's, image of surrogate buying country, where surrogate purchases are conducted in, may play an important role to form consumers' attitude and purchase intention toward products. Furthermore it also possibly affects various dimensions of perceived risk in consumer's information processing. However, though tremendous researches have been carried exploring the effects of diverse dimensions of country of origin, related studies in Internet context has been rarely executed. There have been some studies that prove the positive impact of country of origin on consumer's evaluations as one of information clues in product manufacture descriptions, yet studies detecting the relationship between country image of surrogate buying origin and product evaluations rarely undertaken regarding this specific mall type. Thus, the authors have found it well-worth investigating in this specific retail channel and explored systematic relationships among focal constructs and elaborated their different paths. The authors have proven that country image of surrogate buying origin in the mall, where surrogate malls purchase products in and brings them from for buyers, not only has a positive effect on consumers' product evaluations including attitude and purchase intention but also has a negative effect on all three dimensions of perceived risk: product-related risk, shipping-related risk, and post-purchase risk. Specifically among all the perceived risk, product-related risk which is arisen from high uncertainty of product performance is most affected (${\beta}$= -.30) by negative country image of surrogate buying origin, and also shipping-related risk (${\beta}$= -.18) and post-purchase risk (${\beta}$= -.15) get influenced in order. Its direct effects on product attitude (${\beta}$= .10) and purchase intention (${\beta}$= .14) are also secured. Each of perceived risk dimension is proven to have a negative effect on purchase intention through product attitude as a mediator (${\beta}$= -.57: product-related risk ${\rightarrow}$ product attitude; ${\beta}$= -.24: shipping-related risk ${\rightarrow}$ product attitude; ${\beta}$= -.44: post-purchase risk ${\rightarrow}$ product attitude) as well. From the additional analysis, the paths of consumers' information processing are shown to be different based on their levels of product knowledge. While novice consumers with low level of knowledge consider only perceived risk important, expert consumers with high level of knowledge take both the country image, where surrogate services are conducted in, and perceived risk seriously to build their attitudes and formulate decisions toward products more delicately and systematically, which is in line with previous studies. This study suggests several pieces of academic and practical advice. Precisely, country image of surrogate buying origin does affect on consumer's risk perceptions and behavioral consequences. Therefore a careful selection of surrogate buying origin is recommended. Furthermore, reducing consumers' risk level is required to blossom this new type of retail business whether its consumer are novices or experts. Additionally, since consumer take different paths of elaborating information based on their knowledge levels, sophisticated marketing approaches to each group of consumers are required. For novice buyers strong devices for risk mitigation are needed to induce them to form better attitudes and for experts selections of better and advanced countries as surrogate buying origins are advised while endorsement strategy for the site might work as a reliable information clue to all consumers to mitigate the barriers to purchase goods online. The authors have also explained that the study suffers from some limitations, including generalizability. In future studies, tests of and comparisons among different types of etailers with relevant constructs are recommended to broaden the findings.

• Journal of Preventive Medicine and Public Health
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• v.27 no.4 s.48
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• pp.711-734
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• 1994

Among chemical agents in herbicides, dioxin (2, 3, 7, 8-tetrachloro dibenzo-$\rho$-dioxin : TCDD), a chemical contaminant in herbicides sprayed during the Vietnam War has been known to be the major agent causing toxic effects. Approximately 320,000 korean soldiers participated the Vietnam War from 1964 to 1974. Although the potential hazards of the herbicides among Korean veterans exposed were implicated, the problem had not been a public issue until 1991 when Korean veterans were informed U.S. companies, the herbicides manufacturer payed fund, from which a trust fund for New Zealand and Australian Class members were established in 1985. After a series of appeals and demonstration by the Korean Veterans demanding medical care and compensation for their serious health damages, a bill of medical care and compensation for herbicides victims was promulgated in March 1993 and become effective from May 1993, This study was carried out with two major objectives : the first to understand the health problems caused from the herbicides by reviewing literatures published, and the second to examine the nature and extent of health impacts among Korean veterans exposed and to develop valid study methods for the major study by interviewing and reviewing records on a part of veterans (638 persons) registered and completed medical examination in Seoul Veterans Administration Hospital from June to October 1993. The results obtained are as followings: 1. The literature review of 107 papers revealed that 1) Dioxin is teratogenic, carcinogenic and affects almost all organs including nervous, endocrine, and reproductive systems in animal experiments. 2) The diseases showing evidence of causal association were Hodgkin's disease, non-Hodgkin's disease, lung cancer, lymphoma, soft tissue sarcoma, chloroacne and polyneuropathy when judged on the basis of consistency in study results and biological plausibility. 2. Interview and medical record review study on 638 veterans, though limited validity owing to lack of control group, crude estimates of dioxin exposure levels (no biomarkers measurable), and uncertainty of diagnosis, showed that: 1) Most of the study subject's were in their 40's of age and had been dispatched to Vietnam during the period from $1965{\sim}1970$ around one year. 2) Most frequently complained symptoms in medical examination were motor weakness (32%), sensory abnormalities in extremities (23%), skin diseases (22%), and pain in extremities (20%) whereas in Interview they were more frequent in order of skin problem (44%), motor weakness (38%), sensory abnormalities and pain in extremities(17% and 19% each). Kappa indices on the same category of complaints between two sources of information were variable and relatively low. 3) On medical examination, only a part of the 638 subjects had initial impression (442 pts) and final diagnosis (218 pts) suggesting decision making on diagnosis appeared to be difficult even with all available modern medical technologies: in initial impression disorders from peripheral and central neuropathy were predominant whereas in final diagnosis various types of skin disorder were most frequent 4) When dose-response relationship between several conditions (from questionnaire) and arbitrary exposure scores were examined by CMH linear trend test, spontaneous abortion, sexual problems and health problem of offsprings showed statistically significant linear trends. However, pregnancy, accident and suicidal attempts did not show any relationship in this study capacity. 5) Among complaints, psychosis and neurosis (anxiety, phobia) in interview study, and memory disorder and psychosis in medical record study revealed linear trend. 6) Skin disorder was the only condition showing linear trend in initial impression and none in final diagnosis on medical examination. Even though objective to select out dioxin-related disease or group of diseases from this study was not achieved the research experiences provided firm basis for developing various methodological approaches. 3. From this preliminary study we concluded that a larger scale major epidemiologic study on health impacts of herbicides among Korean veterans exposed is not only Indispensible but also well designed study with more valid exposure information and diagnosis may be able to establish causal relationship between certain groups of diseases and exposure to the herbicides among Korean veterans.

• Korean Journal of Ecology and Environment
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• v.39 no.1 s.115
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• pp.110-118
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• 2006

The Namyang Stream in Hwaong polder was planned for several water uses including recreation, where people can contact the water and consume some amount during the recreational activity. A human health risk was assessed from exposure to E. coli in the Namyang Stream, which receives partially treated wastewater from watershed. The QUAL2E model was applied to simulate stream water quality, and this model was calibrated and verified with field monitoring data. The calibration result showed a high correlation coefficient of greater than 0.9. The mean concentration of E. coli in the Namyang Stream from the QUAL2E output was in the range of 5,000 ${\sim}$ 8,000 MPN 100 mL^{-1}$, which exceeded national and international guidelines. The Beta-Poisson was used to estimate the microbial risk of pathogens ingestion and the Monte-Carlo analysis (10,000 trials) was used to estimate the risk characterization of uncertainty. The Microbial risk assessment showed that the risk ranged from 7.9 ${\times}\;10^{-6}\;to\;9.4\;{\times}10^{-6}$. Based on USEPA guidelines, the range of $10^{-6}\;to\;10^{-8}$ was considered reasonable levels of risk for communicable disease transmission from environmental exposure, and the risk above $10^{-4}$ was considered to be in the danger of infection. Therefore, water quality of the Namyang Stream might not be in the danger of infection although it exceeded national and international guidelines. However, it was in the range of communicable disease transmission, and thorough wastewater collection and treatment at the source is recommended to secure safe recreation water quality.

• Journal of the Korean Society for Library and Information Science
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• v.4
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• pp.43-71
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• 1975

Operations research has developed rapidly since its origins in World War II. Practitioners of O. R. have contributed to almost every aspect of government and business. More recently, a number of operations researchers have turned their attention to library and information systems, and the author believes that significant research has resulted. It is the purpose of this essay to introduce the library audience to some of these accomplishments, to present some of the author's hypotheses on the subject of library management to which he belives O. R. has great potential, and to suggest some future research directions. Some problem areas in librianship where O. R. may play a part have been discussed and are summarized below. (1) Library location. It is usually necessary to make balance between accessibility and cost In location problems. Many mathematical methods are available for identifying the optimal locations once the balance between these two criteria has been decided. The major difficulties lie in relating cost to size and in taking future change into account when discriminating possible solutions. (2) Planning new facilities. Standard approaches to using mathematical models for simple investment decisions are well established. If the problem is one of choosing the most economical way of achieving a certain objective, one may compare th althenatives by using one of the discounted cash flow techniques. In other situations it may be necessary to use of cost-benefit approach. (3) Allocating library resources. In order to allocate the resources to best advantage the librarian needs to know how the effectiveness of the services he offers depends on the way he puts his resources. The O. R. approach to the problems is to construct a model representing effectiveness as a mathematical function of levels of different inputs(e.g., numbers of people in different jobs, acquisitions of different types, physical resources). (4) Long term planning. Resource allocation problems are generally concerned with up to one and a half years ahead. The longer term certainly offers both greater freedom of action and greater uncertainty. Thus it is difficult to generalize about long term planning problems. In other fields, however, O. R. has made a significant contribution to long range planning and it is likely to have one to make in librarianship as well. (5) Public relations. It is generally accepted that actual and potential users are too ignorant both of the range of library services provided and of how to make use of them. How should services be brought to the attention of potential users? The answer seems to lie in obtaining empirical evidence by controlled experiments in which a group of libraries participated. (6) Acquisition policy. In comparing alternative policies for acquisition of materials one needs to know the implications of each service which depends on the stock. Second is the relative importance to be ascribed to each service for each class of user. By reducing the level of the first, formal models will allow the librarian to concentrate his attention upon the value judgements which will be necessary for the second. (7) Loan policy. The approach to choosing between loan policies is much the same as the previous approach. (8) Manpower planning. For large library systems one should consider constructing models which will permit the skills necessary in the future with predictions of the skills that will be available, so as to allow informed decisions. (9) Management information system for libraries. A great deal of data can be available in libraries as a by-product of all recording activities. It is particularly tempting when procedures are computerized to make summary statistics available as a management information system. The values of information to particular decisions that may have to be taken future is best assessed in terms of a model of the relevant problem. (10) Management gaming. One of the most common uses of a management game is as a means of developing staff's to take decisions. The value of such exercises depends upon the validity of the computerized model. If the model were sufficiently simple to take the form of a mathematical equation, decision-makers would probably able to learn adequately from a graph. More complex situations require simulation models. (11) Diagnostics tools. Libraries are sufficiently complex systems that it would be useful to have available simple means of telling whether performance could be regarded as satisfactory which, if it could not, would also provide pointers to what was wrong. (12) Data banks. It would appear to be worth considering establishing a bank for certain types of data. It certain items on questionnaires were to take a standard form, a greater pool of data would de available for various analysis. (13) Effectiveness measures. The meaning of a library performance measure is not readily interpreted. Each measure must itself be assessed in relation to the corresponding measures for earlier periods of time and a standard measure that may be a corresponding measure in another library, the 'norm', the 'best practice', or user expectations.

• Journal of Radiation Protection and Research
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• v.23 no.4
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• pp.229-236
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• 1998

In order to establish a testing system for personnel dosimetry performance, the radiation fields from photons, beta particles and neutrons are required, in recent, Korea Institute of Nuclear Safety(KINS) established the reference radation fields except neutrons and tested a variety of their properties. As a result of the test, the reference beams were shown to meet satisfactorily not only the standards of the International Organization for Standardization(ISO), but also the standard levels of the developed countries which are intercomparable with the international traceability. This paper describes the reference beam of gamma radiation. The self-designed and established reference radiation fields were investigated and analyzed by ISO and other international standards. The secondary photon contribution and the beam uniformity of the gamma radiation field were measured and evaluated to fulfill those requirements suggested by the ISO-4037. The measured air kerma rate for the $^{137}$Cs and $^{60}$Co gamma fields was 0.1891 $\sim$ 23.4967 $\mu$Gy/s sand 0.5844 $\sim$ 15.9954 $\mu$Gy/s respectively. The uncertainty with 95 % confidence level of the measured air kerma rate was determined to be less than 2.5 % which is comparable to the international reference gamma radiation fields. It was found that the evaluated air kerma calibration factors of Exradin ionization chamber were in good agreement within 0.9 % and 0.03 % with those given by PTB and NIST, respectively. The gamma radiation fields installed at KINS can maintain traceability systems in Korea, Germany and United State.