• Title/Summary/Keyword: viewpoints

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Understanding the Mismatch between ERP and Organizational Information Needs and Its Responses: A Study based on Organizational Memory Theory (조직의 정보 니즈와 ERP 기능과의 불일치 및 그 대응책에 대한 이해: 조직 메모리 이론을 바탕으로)

  • Jeong, Seung-Ryul;Bae, Uk-Ho
    • Asia pacific journal of information systems
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    • v.22 no.2
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    • pp.21-38
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    • 2012
  • Until recently, successful implementation of ERP systems has been a popular topic among ERP researchers, who have attempted to identify its various contributing factors. None of these efforts, however, explicitly recognize the need to identify disparities that can exist between organizational information requirements and ERP systems. Since ERP systems are in fact "packages" -that is, software programs developed by independent software vendors for sale to organizations that use them-they are designed to meet the general needs of numerous organizations, rather than the unique needs of a particular organization, as is the case with custom-developed software. By adopting standard packages, organizations can substantially reduce many of the potential implementation risks commonly associated with custom-developed software. However, it is also true that the nature of the package itself could be a risk factor as the features and functions of the ERP systems may not completely comply with a particular organization's informational requirements. In this study, based on the organizational memory mismatch perspective that was derived from organizational memory theory and cognitive dissonance theory, we define the nature of disparities, which we call "mismatches," and propose that the mismatch between organizational information requirements and ERP systems is one of the primary determinants in the successful implementation of ERP systems. Furthermore, we suggest that customization efforts as a coping strategy for mismatches can play a significant role in increasing the possibilities of success. In order to examine the contention we propose in this study, we employed a survey-based field study of ERP project team members, resulting in a total of 77 responses. The results of this study show that, as anticipated from the organizational memory mismatch perspective, the mismatch between organizational information requirements and ERP systems makes a significantly negative impact on the implementation success of ERP systems. This finding confirms our hypothesis that the more mismatch there is, the more difficult successful ERP implementation is, and thus requires more attention to be drawn to mismatch as a major failure source in ERP implementation. This study also found that as a coping strategy on mismatch, the effects of customization are significant. In other words, utilizing the appropriate customization method could lead to the implementation success of ERP systems. This is somewhat interesting because it runs counter to the argument of some literature and ERP vendors that minimized customization (or even the lack thereof) is required for successful ERP implementation. In many ERP projects, there is a tendency among ERP developers to adopt default ERP functions without any customization, adhering to the slogan of "the introduction of best practices." However, this study asserts that we cannot expect successful implementation if we don't attempt to customize ERP systems when mismatches exist. For a more detailed analysis, we identified three types of mismatches-Non-ERP, Non-Procedure, and Hybrid. Among these, only Non-ERP mismatches (a situation in which ERP systems cannot support the existing information needs that are currently fulfilled) were found to have a direct influence on the implementation of ERP systems. Neither Non-Procedure nor Hybrid mismatches were found to have significant impact in the ERP context. These findings provide meaningful insights since they could serve as the basis for discussing how the ERP implementation process should be defined and what activities should be included in the implementation process. They show that ERP developers may not want to include organizational (or business processes) changes in the implementation process, suggesting that doing so could lead to failed implementation. And in fact, this suggestion eventually turned out to be true when we found that the application of process customization led to higher possibilities of failure. From these discussions, we are convinced that Non-ERP is the only type of mismatch we need to focus on during the implementation process, implying that organizational changes must be made before, rather than during, the implementation process. Finally, this study found that among the various customization approaches, bolt-on development methods in particular seemed to have significantly positive effects. Interestingly again, this finding is not in the same line of thought as that of the vendors in the ERP industry. The vendors' recommendations are to apply as many best practices as possible, thereby resulting in the minimization of customization and utilization of bolt-on development methods. They particularly advise against changing the source code and rather recommend employing, when necessary, the method of programming additional software code using the computer language of the vendor. As previously stated, however, our study found active customization, especially bolt-on development methods, to have positive effects on ERP, and found source code changes in particular to have the most significant effects. Moreover, our study found programming additional software to be ineffective, suggesting there is much difference between ERP developers and vendors in viewpoints and strategies toward ERP customization. In summary, mismatches are inherent in the ERP implementation context and play an important role in determining its success. Considering the significance of mismatches, this study proposes a new model for successful ERP implementation, developed from the organizational memory mismatch perspective, and provides many insights by empirically confirming the model's usefulness.

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Improving the Accuracy of Document Classification by Learning Heterogeneity (이질성 학습을 통한 문서 분류의 정확성 향상 기법)

  • Wong, William Xiu Shun;Hyun, Yoonjin;Kim, Namgyu
    • Journal of Intelligence and Information Systems
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    • v.24 no.3
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    • pp.21-44
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    • 2018
  • In recent years, the rapid development of internet technology and the popularization of smart devices have resulted in massive amounts of text data. Those text data were produced and distributed through various media platforms such as World Wide Web, Internet news feeds, microblog, and social media. However, this enormous amount of easily obtained information is lack of organization. Therefore, this problem has raised the interest of many researchers in order to manage this huge amount of information. Further, this problem also required professionals that are capable of classifying relevant information and hence text classification is introduced. Text classification is a challenging task in modern data analysis, which it needs to assign a text document into one or more predefined categories or classes. In text classification field, there are different kinds of techniques available such as K-Nearest Neighbor, Naïve Bayes Algorithm, Support Vector Machine, Decision Tree, and Artificial Neural Network. However, while dealing with huge amount of text data, model performance and accuracy becomes a challenge. According to the type of words used in the corpus and type of features created for classification, the performance of a text classification model can be varied. Most of the attempts are been made based on proposing a new algorithm or modifying an existing algorithm. This kind of research can be said already reached their certain limitations for further improvements. In this study, aside from proposing a new algorithm or modifying the algorithm, we focus on searching a way to modify the use of data. It is widely known that classifier performance is influenced by the quality of training data upon which this classifier is built. The real world datasets in most of the time contain noise, or in other words noisy data, these can actually affect the decision made by the classifiers built from these data. In this study, we consider that the data from different domains, which is heterogeneous data might have the characteristics of noise which can be utilized in the classification process. In order to build the classifier, machine learning algorithm is performed based on the assumption that the characteristics of training data and target data are the same or very similar to each other. However, in the case of unstructured data such as text, the features are determined according to the vocabularies included in the document. If the viewpoints of the learning data and target data are different, the features may be appearing different between these two data. In this study, we attempt to improve the classification accuracy by strengthening the robustness of the document classifier through artificially injecting the noise into the process of constructing the document classifier. With data coming from various kind of sources, these data are likely formatted differently. These cause difficulties for traditional machine learning algorithms because they are not developed to recognize different type of data representation at one time and to put them together in same generalization. Therefore, in order to utilize heterogeneous data in the learning process of document classifier, we apply semi-supervised learning in our study. However, unlabeled data might have the possibility to degrade the performance of the document classifier. Therefore, we further proposed a method called Rule Selection-Based Ensemble Semi-Supervised Learning Algorithm (RSESLA) to select only the documents that contributing to the accuracy improvement of the classifier. RSESLA creates multiple views by manipulating the features using different types of classification models and different types of heterogeneous data. The most confident classification rules will be selected and applied for the final decision making. In this paper, three different types of real-world data sources were used, which are news, twitter and blogs.

Study on Implementation Measures of Provincial Self-governing Police System : Focusing on the Implication from Enlargement of Work Scope of Self-governing Police of Jeju Province (광역자치경찰제의 정착방안에 관한 연구 - 제주자치경찰의 사무확대에 대한 시사점을 중심으로 -)

  • Kim, Seong-Hee
    • Korean Security Journal
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    • no.59
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    • pp.37-69
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    • 2019
  • According to viewpoints of researchers and stakeholders, various opinions can be suggested on self-governing police system. Therefore, success of Korean self-governing police system will be defending on how to balance among conflicting values such as Empowerment, Political neutrality, Financial issues, Comprehensive competence in maintaining public safety. Before the launching of self-governing police system nation-wide, the experience of Jeju provincial police will be valuable model case. In specific, enlargement of work scope of self-governing police in Jeju province which has been introduced since last year will be a useful reference. There is more pessimism about self-governing police of Jeju province so far. However, this perspective is mostly based on the issue regarding hardwares such as manpower, equipment, law and organization. Issues regarding softwares such as organizational culture, operation system and work process need more attention to evaluate self-governing police system properly. To mark the first year after enlargement of work scope of Jeju police, this study demonstrate the overall result and implications of self-governing police of Jeju province based on documents, statistics, reports and media reports. In result, several preconditions are needed to implement the self-governing police system nation-wide successfully. 1. Strengthen the link between local government and local police 2. Establish the foundation for collaboration of state and local police 3. Enhance the aspect of citizen autonomy in local level 4. Reinforcing the capability of handling situation of state and local police 5. Invigorating the inter-organizational working group to operate self-governing police system effectively. The self-governing police system is unclosed topic to discuss. After this study, in-depth studies should be followed with more resources. Particularly, additional perspective including redundancy and equity need to be considered regarding self-governing police. By getting with the changes of macroscopic trends - lowbirth and aging, the fourth industrial revolution and possible reunification of north and south Koreas - these studies should suggest the long-term blueprint of self-governing police system of Korea.

The Morpho-Imaganary Viewpoints of Lee Je-ma and the Morpho-Imaganary recognitions of Sasang Constitutional Medicine (동무공(東武公)의 형상관(形象觀)과 사상의학(四象醫學)의 형상의학정신(形象醫學精神))

  • Song, Il-byung
    • Journal of Sasang Constitutional Medicine
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    • v.11 no.1
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    • pp.1-13
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    • 1999
  • Lee Je-ma created Sasang Constitutional Medicine from the insight of different congenital formation of Viscera which was based on his own Morpho-Imaganary recognition of human beings. The basic principles to understand human beings are as follows. The first, human beings are morphologically figured based on the human nature. The Second, Morpho-lmaganary recognition was the understanding to all the things including human with the rule of society and the relationships. affairs-mind-body-objects. The Morpho-Imaganary characteristics of Sasang Constitutional Medicine are as follows. The first, Sasang Constitutional Medicine recognize the symptoms and diseases as the aspect of structure and function at the same time. The second, it recognize the symptoms and diseases with the viewpoint of Change.

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Population Thoughts in East Asia: A Comparison of Hung Liang-Chi and Malthus (동아시아의 인구사상: 홍량길과 맬서스의 비교)

  • Park Sang-Tae
    • Korea journal of population studies
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    • v.27 no.1
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    • pp.171-201
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    • 2004
  • Modern sciences in the West are deeply rooted in the Greek and Roman cultural heritage. Consequently, the academic achievements accomplished by the scholars of the Arabs including Persian world, the profound thoughts developed in the Indian subcontinent, and the excellent works made by the East Asian scholars have mostly been neglected in the past. This paper attempts to compare the thoughts and theories on population developed by the Western scholars with those of East Asian scolars, in chronological order, ancient, mediaeval, and modern period before Malthus. The thesis that excessive population growth may reduce output per worker, depress levels of living for the masses and engender strife is of great antiquity. In fact, overpopulation in East Asia, especially in China, goes back to very ancient times, most Confucian scholars maintained the notion of a numerical balance between population and environment. They also looked for means to check the increase in numbers. The foundations of a theory of optimum population level, fully developed in the twentieth century, can be found in their writings. Although early population thoughts in China had not advanced far in the analysis of the significance of population size and growth, it had taken only a few steps forward. At some times and to some observers, populousness appeared desirable; at other times and to other observers, it seemed all too evident that the number of people could become too great. These viewpoints foreshowed some of the later developments. The early population literatures reviewed here seem to consist of a number of quite isolated contributions. In fact, however, there may have been a greater continuity of thought than now appears, for many of the contributions may have been lost and there are many gaps in the record. An intensive review on comparing two works, those of Malthus' and Hong, Liang-chi's, are presented in this paper. Only five years before Malthus published his famous work, An Essay on the Principle of Population, Hong published his theories on population. Some of them, Hong insisted, are very similar to the Malthusian concepts of geometrical increase, natural and artificial checks of population. Despite the excellent works in the ancient period, this paper concludes with an investigation of the reasons why modem achievements in scientific areas in the East Asia have been far behind that of the West.

The Difference between the Interpretations of Korean Language Experts and Science Education Experts on the Cognitive Domain of Science Achievement Standards: Focus on 'Explain' (과학과 교육과정 성취기준의 인지적 영역에 대한 국어교육전공자와 과학교육전공자의 해석 차이:설명하기를 중심으로)

  • Song, Eunjeong;Je, Minkyeong;Cha, Kyungmi;Yoo, Junehee
    • Journal of The Korean Association For Science Education
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    • v.37 no.2
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    • pp.371-382
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    • 2017
  • The texts in the national science curriculum documents are expected to be interpreted in the same meaning as that of the authors. In this study, the science achievement standards in national curriculum documents were examined through an analysis of the differences between the interpretations of Korean language education experts and science education experts. Three Korean language education experts designed and utilized an analysis framework on science curriculum standards from their viewpoints while three science education experts utilized TIMSS cognitive domain framework to analyze the 2009 Korean revised science curriculum achievement standards. The differences between interpretations of both groups were analyzed qualitatively through interviews. First of all, the two groups seemed to have different meanings for terms such as "explain," "analyze," "define," and "cause and effect." The science achievement standards described by general verbs like "explain" were interpreted in various ways. The verb "explain" that appears many times in the science achievement standards seem to be representing the "describe" subsections in the framework of Korean language education expert rather than the "explain" subsections of the framework of science education experts. Science education experts seemed to focus on prepositional phrases, which indicate inquiry process, while Korean language education experts seemed to focus on objective phrases. Moreover, the science education experts would interpret the achievement standards based on their background knowledge while the Korean language education experts would interpret them based on the structure of the sentences. This study suggests that achievement standards should specifically indicate the levels and scopes of cognitive domain as well as the knowledge domain. Also, integrations of achievement standards in cognitive domains of Korean language and science subjects should be considered.

A Study on Curriculum Improvement of the Korea Army Nursing Academy (국군간호사관학교 교육과정 개선을 위한 기초 연구)

  • 고자경
    • Journal of Korean Academy of Nursing
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    • v.13 no.2
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    • pp.22-43
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    • 1983
  • 1. Need for and Purpose of the Study. There is an increasing demand for curriculum improvement of the Korean Army Nursing Academy (KANA), since it was upgraded into 4-year institution of higher learning from 3-year one. In particular, it is strongly advocated that the KANA needs the outside expertise for its curriculum improvement-namely not only from the internal military view of points but also from the viewpoints of professional educational society, In line with such a necessity for the study, this study was aimed at 1) analyzing the current actual practices of KANA'S curriculum, 2) investigating the desired practices of KANA'S curriculum, and 3) identifying the discrepancy between the actual and desired practices of curriculum. 2. Problems for the Study This study had 4 problems to be answeared as follows: 1) What are the actual curriculum practices of KANA? 2) What are the desired curriculum practices of KANA? 3) How are the extents of perception of actual and desired curriculum different in four groups (student, faculty & administrator, nurse, and medical doctor in militay hospital) ? 4) What are the restraining forces that impede the change from actual to desired curriculum practices? 5) What are the relationships of curriculum component,』 in actual and desired curriculum practices? 3. Methods and Procedures This study was conducted by means of document analysis in addition to literature review and by means of needs assessment questionnaire which was developed by the researcher. The questionnaire included 62 statments with 7 questions for demographic data collection. The needs assessment questionnaire was managed to a total of 243 subjects (100 students, 46 faculty & administrators, 55 nurses, and 42 medical doctors), The collected data were treated using SPSS computer system so as to calculate mean scores, standard deviations, and correlation coefficients. The significance test was made through t-test and one-way ANOVA. The statistical significance level was set at both .05 and .01 level. 4. Major findings The major findings in this study are as follows: 1) The score of desired practices was significantly greater than that of actual practices, representing a strong need for curriculum betterment. 2) There were significant differences in the perceptions of actual practices as well as desired practices among four groups (student, faculty & administrater, nurse, and medical doctor). 3) The most frequently selected restraining forces were army's inherent character, economical limitation, and educational expertise limitations. 4) Such variables as sex, position attachment to the KANA and grade made a statistically significant effect on the perception of desired curriculum practice, while the variables like marrige, position, and military class made it on the perception of actual curriculum practice. 5) The coefficients among the curriculum components were lower in perception of the actual curriculum practices than those in the desired practices. 5. Conclusions The conclusions based on the major findings of this study are as follows: 1) The current curriculum development procedure of the KANA is not consistent with the theoretical frame of systematic development sarategy of curriculum. 2) There are wide conflicts among the groups who are supposed to participate in curriculnm development, concerning the actual and desired practices of KANN'S curriculum. 3) A great deal of need for curriculum improvement for the KANA is clearly felt, and in particular, in the process of teaching and learning. 4) Each component of curriculum is not intergrated into a whole development procedure, being segregated each other. 5) For better curriculum improvement, such restraining forces as financial and professional limitations should be eliminated. 6. Recommendations 1) For Further Research a. There is a need to replicate this study after in-depth statistical analysis of each item of need assessment questionnaire, and with more representative subjects. b. A study should be conducted which. has its focus on the analysis of restraining forces for the change from actual to desired curriculum practices of the KANA. 2) For KANA'S Curriculum Improvement a. There is a need to promote the professional expertise of the participants in curriculum development and the communication among them. b. It is desirable to establish an institution or section of administration, which is soley in charge of curriculum development. c. To better develop KANA's curriculum not only faculty and administrators but also students should be encouraged to participate in development process, while the military medical doctors' participation should be carefully considered.

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A Study on the Religious Costume in Korea - Buddhist and Taoist Costume - (한국(韓國) 종교복식(宗敎服飾)에 관(關)한 연구(硏究) - 불교(佛敎)와 도교복식(道敎服飾)을 중심(中心)으로 -)

  • Im, Yeong-Ja
    • Journal of the Korean Society of Costume
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    • v.14
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    • pp.63-73
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    • 1990
  • The thought of three religious, Confucianism, Buddhism, and Taoism, had been the mainaxis of Korean spirit of the past. This study is centered on Buddhist and Taoist costume. There have been a lot of studies on Korean costume from many viewpoints. However, there have been few approaches to the inner !"ide of it. That is to say, the research on spiritual back-ground or religious correlation has not done yet. And especially, we are wholly lacking the studies on Taoist costume. In this dissertation, I investigate how they had come to wear Buddhist costume and how it trans, on the basis of related documentary records and existing remains. I also inquiry Taoist costume which was worn at Taoist ceremony in our country, with the help of Korean books and documents and of the sources of Packwoonkwan in China. In the case of Topobyunjeung in Korean costume, in particular, we can catch the source of it only after studying the religious side of Taoist costume and Buddhist costume. As revealed in the theory of Topobyunjeung in Ojuyunmoonja-ngsango by Lee, Kyu Kyung, even old masters and great Confucianists could not know whether Topo, the ordinary clothes of the Sadaeboo, originated from Taoist costume or Buddhist costume. There have been many opinions about the origin, but even now it is true that no one has made it clear. Therefore in this dissertatio I demonstrate mainly how Topo and Hakchangeui appeared in Korean costume through Taoist costume. It is said that Taoists, Buddhists, and literary men wore Topo, Chickchul, and Chickshin in Song dynasty of China. Topo was a clerical robe of Taoists and was also an ordinary clothes. Chick-chul was a clerical robe of Buddhists, and Chick-shin was worn by Zen priests in Won dynaty. Over the Po, Buddhist wore a large robe, namely Kasa, and Taoist wore Packhakchang like Wooeui, when they attended at the religious ceremony. And they regarded such manner of dressing as ceremonial full-dress attire. The style of Topo in China was Saryunggyogeo. The is th say that they put the black Yeon along Sajoo, which are Young, Soogoo, Keum, and Keo, and that they wore Sajodae around their waists so as to let the band down in front of them. Our existing type of Topo is that of Chickryung-gyoin. The characteristics of the type are its Koreum hung on the dress, no Yeon along Sajoo, and Soopok at the back of the dress. And when they put on the dress, they wear Saejodae around their waists. These characteristics considered, we can find the source of Topo from the Po of Chickshin among Buddhist costume. Other types of Topo are those that were transformed elegantly according to our national manners and customs in our country. So-called Wooeui in Chiness Taoism is Hakchang. Originally it was made by weaving for of cranes or other feathered birds. Its remarkable feature is the wide sleeves. Later they called such a robe with wide sleeves Hakchang. Our hakchangeui has Yeon along Sajoo and a belt around waist. We can guess that the features of Topo and wide-sleeved Hakchang mingled and turned into Hakchangeui. Or it might also be that Topa worn by Taoist was regarded as Hakchang and Topa which has Yeon along Sajoo was regarded as Hakchangeui in our country. Such type of Hakchang worn by Taoists was well shown in the Buddhist and Taoist paintings among "The Pictures of Hills, Waters, and Folks" in the latter half of the 16th century. In China Hakchang with a belt around waist could not be seen. Comparing our style of Hakchangeui with the Chinese style, we can recognize the former was similar to that of Chinese Topa. From this, we gather that Topa was regarded as Hakchang, Wooeui worn by Taoists, Ascetics and True Men in Korea. Furthermore I also gather that our Hakchangeui, which has Tongjeong, Koreurn and a belt around waist, was a transformed style in our own country. From the above, we can realize that in costume the three religions, Confucianism, Buddhism, and Taoism, cannot be treated separately although they are different each other in the essential thought. We have to recognize that Korean Costume was established under the closely connected correlation among the religions and that it was transfigured and accepted according to the cultural characteristics. This study is significant in that it is the first attempt to understand Korean costume through the religous approach, which has never been made in our Korean costume studies. We are demanded even more wide and profound investigation on the religious side of costume throughout the general field of costume studies.

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Effective Coastal Water Quality Management and Marine Environmental Impact Assessment (연안의 효율적 수질관리 방향과 해양환경영향평가)

  • Lee, Dae-In;Eom, Ki-Hyuk;Kim, Gui-Young;Hong, Sok-Jin;Lee, Won-Chan;Jang, Ju-Hyoung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.14 no.1
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    • pp.29-37
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    • 2008
  • This study examined principles and techniques of efficient water quality management as well as total coastal pollutant loads and the relevant examples in the advanced countries from the viewpoints of water quality improvement and pollution control in coastal areas. The problems and improvements in an estimation of the current total pollutant loads were also pointed out. In addition, discussion was made on the relationship between total pollutant loads and environmental capacity as well as particulars requiring extensive examination on access to and study on water quality model used as prediction tool for marine environment. Furthermore, this study proposed details of and improvement plans for water quality control to be reflected and absorbed into systems and policies related to coastal water quality. In coastal areas, which are subject to total coastal pollutant loads, it is necessary to calculate pollutant loads reduction and allocation, to propose them in detail in statement in relations to new pollution sources for the corresponding projects or plans in environmental impact assessment and prior environmental review system. Also, in relations to regional plans for coastal management, the local government concerned must focus more on environmental management plan to implement data on pollution sources and pollutant loads flown into sea areas under basic jurisdiction, therefore it is required to actively respond to expansion and introduction of total coastal pollutant loads system in the future. Total coastal pollutant loads system must be expanded and executed by considering characteristics of sea area and changes in the environment of land. For pollution sources in land, the competent authorities in charge of coastal environment will need to initiatively administer supervision, monitoring activities and achieve integration and operation of the related laws by preparing legal bases for management system or adjusting the related laws.

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Cation Exchange Capacities, Swelling, and Solubility of Clay Minerals in Acidic Solutions : A Literature Review

  • Park, Won Choon
    • Economic and Environmental Geology
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    • v.12 no.1
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    • pp.41-49
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    • 1979
  • A literature review is made on the physical and chemical characteristics of clay minerals in acidic solutions from the mineralogical and hydrometallurgical viewpoints. Some of the important characteristics of clays are their ability to cation exchange, swelling, and incongruent dissolution in acidic solutions. Various clay minerals can take up metallic ions from solution via cation exchange mechanism. Generally, cation exchange capacity increases in the following order : kaolinite, halloysite, illite, vermiculite, and montmorillonite. In acidic solutions, the cation uptake such as copper by clay minerals is strongly inhibited by hydrogen and aluminum ions and thus is not economically significant factor for recovery of metals such as uranium and copper. In acidic solutions, the cation uptake is substial. Swelling is minimal at lower pH, possibly due to lattice collapse. Swelling may be controllable with montmorillonite type clays by exchanging interlayer sodium with lithium and/or hydroxylated aluminum species. The effect of add on clay minerals are : 1. Division of aggregates into smaller plates with increase in surface area and porosity. 2. Clay-acid reactions occur in the following order: (i) $H^+$ replacement of interlayer cations, (ii) removal of octahedral cations, such as Al, Fe, and Mg, and (iii) removal of tetrahedral Al ions. Acid attack initiates, around the edges of the clay particles and continued inward, leaving hydrated silica gel residue around the edges. 3. Reaction rates of (ii) and (iii) are pseudo-1st order and proportional to acid concentration. Rate doubles for every temperature increment of $10^{\circ}C$. Implications in in-situ leaching of copper or uranium with acid are : 1. Over the life span of the operation for a year or more, clays attacked by acid will leave silica gel. If such gel covers the surface of valuable mineral surfaces being leached, recovery could be substantially delayed. 2. For a copper deposit containing 0.5% each of clay minerals and recoverable copper, the added cost due to clay-acid reaction is about 1.5c/lb of copper (or 0.93 lbs of $H_2SO_4/1b$ of copper). This acid consumption by clay may be a factor for economic evaluation of in-situ leaching of an oxide copper deposit.

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