• Title/Summary/Keyword: time representation

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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.

Place-myth of The Scenic Beauty from Mt. Kumgang : The social nature and the travel geography of noted mountains ('금강산'에서 전승되는 아름다움의 장소신화 : 사회적 자연과 명산의 여행지리)

  • Shin, Sung Hee
    • Journal of the Korean association of regional geographers
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    • v.22 no.1
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    • pp.151-167
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    • 2016
  • Conventional social science typically regards the idea of a 'mountain' as part of 'nature' and a physical environment existing separately from, or prior to, human society and culture. However, in Korea, which is 70% mountainous land, the 'mountain' is part of a unique 'social nature'. This research develops the idea that in this context the mountain is a social nature and a cultural landscape which are tied heavily to the idea of travel. The article interrogates why the scenic beauties of Mt. Kumgang have been perceived and conveyed through multiple generations since the Chosun Dynasty period. Focusing on Mt. Kumgang, this article illustrates how strongly people have held dreams of mountain travel, for the whole life-time. Travel writings(or accounts of trips to the mountain) and artwork have played a particularly important role in creating Mt. Kumgang's reputation as the most beautiful mountain in the country. At the same time, the access to the mountain was often a dangerous adventure, with many travelers facing hunger and extreme physical challenges. As portrayed in writings and artwork, the overall effect of these dynamics was the creation of a socionatural place of striking beauty that even seemed to have mystical or magical fantasy. According to Confucian ideals, full appreciation of nature and its beauty was key to understanding the logics of the universe and to achieving a high moral standard, which contributed to decide to leave for the mountain as well. The essays, poems, and paintings of Mt. Kumgang since the Chosun Dynasty period that portrayed the mountain's beauty collectively served to produce the mountain as a socionatural landscape engendered with potent place-myths, important historical meaning, and strong aesthetic associations. Thus, the travel to the mountain seemed never completed over until travelers had completed various artistic representations to record and to memorize what they'd done and seen in Mt. Kumgang, which had been performed for the strong purpose of social sharing of the real the mountain's beauties and itinerary.

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Facial Expression Control of 3D Avatar using Motion Data (모션 데이터를 이용한 3차원 아바타 얼굴 표정 제어)

  • Kim Sung-Ho;Jung Moon-Ryul
    • The KIPS Transactions:PartA
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    • v.11A no.5
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    • pp.383-390
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    • 2004
  • This paper propose a method that controls facial expression of 3D avatar by having the user select a sequence of facial expressions in the space of facial expressions. And we setup its system. The space of expression is created from about 2400 frames consist of motion captured data of facial expressions. To represent the state of each expression, we use the distance matrix that represents the distances between pairs of feature points on the face. The set of distance matrices is used as the space of expressions. But this space is not such a space where one state can go to another state via the straight trajectory between them. We derive trajectories between two states from the captured set of expressions in an approximate manner. First, two states are regarded adjacent if the distance between their distance matrices is below a given threshold. Any two states are considered to have a trajectory between them If there is a sequence of adjacent states between them. It is assumed . that one states goes to another state via the shortest trajectory between them. The shortest trajectories are found by dynamic programming. The space of facial expressions, as the set of distance matrices, is multidimensional. Facial expression of 3D avatar Is controled in real time as the user navigates the space. To help this process, we visualized the space of expressions in 2D space by using the multidimensional scaling(MDS). To see how effective this system is, we had users control facial expressions of 3D avatar by using the system. As a result of that, users estimate that system is very useful to control facial expression of 3D avatar in real-time.

PASKYULA's Theory of Art (파스큐라의 미술론)

  • Jung, Ju-Young
    • The Journal of Art Theory & Practice
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    • no.5
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    • pp.43-80
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    • 2007
  • PASKYULA was formed in September, 1923 through the union of artists involved in two art groups: Kim Ki-Jin, Kim Bok-Jin, Yeon Hak-Nyeon who had previously participated in the ToWolHoi, and Park Young-Hi, Lee Sang-Hwa, An Seok-Ju, former members of the BaeckJo. After its founding, the PASKYULA artists had been searching for the social function of art to reform the harsh reality of Minjung and the nation with criticism toward society as well as art world. Their art theory for MinJung could grow relatively ease in relation to changing social and political conditions in the early 1920s. In August, 1925, PASKYULA organized the Korea Artista Proletaria Federatio with the YeomGunSa, and laid the groundwork for Proletariat art movement which was regularized in the late 1920s. From PASKYULA up to the early state of KAPF, the theory of art advocated by Kim Bok-Jin and An Seok-Ju could be summarized as "art for MinJung". At that time, widely ranging discourses on MinJung, however, was spawned in art theory, because many intellectuals-including artists and writers-begun to pay more attention to MinJung, who emerged as one of the social forces after the Samil Independent Movement. Sometimes, MinJung was construed as the target of enlightenment from a negative viewpoint. On the other hand, several intellectuals under the influence of individualism asserted that the discussion itself on MinJung exerted an evil influence on art. In contrast of these cases, the PASKYULA artists including Kim Bok-Jin, An Seok-Ju perceived that MinJung had the potential to change society, and regarded them as "a creator of genuine civilization and art". In the PASKYULA artist's writings, the concept of MinJung was often overlapped with the meaning of the Choson nation suffering under colony. Although their concept of MinJung was transformed gradually into the proletariat as they were under the strong influence of socialism, it did not change that they grasped the realities of the whole Choson Peninsula through the proletarian consciousness. In the early state of PASKYULA, the methodology for social function of art was presented in a twofold manner. First of all, Kim Bok-Jin emphasized on the necessity of education to improve MinJung's way of life through art, and it was embodied by the organization of ToWol Art Workshop and public lecture. Also, he championed "the popularization of art", which was one of methods to distribute art to MinJung. According to the PASKYULA artists, art should be not art for art' sake but art for MinJung. That was why they advocated the convergence of art and MinJung's life. Especially Kim Bok-Jin affirmed a link between art and industry because he considered industry the field inextricably linked with MinJung's life. In this context, his idea could be read as the generalization and equalization within the framework of possession. Kim Bok-Jin thought that the social ramifications of capitalism deprived MinJung of their right to enjoy art, and emphasized the artist' social role to return the right to them. That is, the even distribution of art was mainly discussed than the contents of art in the half of 1920s. By 1925, the contents of art itself became an issue in the PASKYULA art theory, and it was based in realism. Kim Bok-Jin and An Seok-Ju insisted that art should be reflection of real life. At that time, realism acquired the representation of MinJung and the nation's realities not realistic style. In fact, the various Western art styles including Futurism, Constructivism, Cubism etc. were exploited in the PASKYULA's visual images. Western art, target of criticism on theory, was selectively adopted in the works which were produced by Kim Bok-Jin and An Seok-Ju. Kim Bok-Jin's MoonYeUnDong cover design was conceived of as the example in which Western art was adopted with it's ideology under the influence of MAVO, while Western art shown in An Seok-Ju's illustrations served as a decorative function in many cases. Especially, An Seok-Ju attempted the various styles of Western art simultaneously, which may be seen as representing that PASKYULA did not have a firm ideology for their style. Also, it can be read as showing his hasty zeal to overcome Western art rapidly. The wish to establish "art for MinJung" as soon as possible was accompanied with the will to jump over the all steps of Western art though it was superficial. This aspiration of PASKYULA was expressed through the mass media, which had the potential for communicating to MinJung. At this point, there was a significant disparity between PASKYULA and another art groups in the first half of 1920s. However, the PASKYULA's method on the basis of the mass media could not but have a certain limitation because of the medium's properties. Nevertheless, PASKYULA' attempts may be considered to be valuable in sense that they expended the boundaries of Korean modern art into the commercial art questioning the matter of the distribution for art.

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A Study on the Period of Commendatorying Jeongnyeo(旌閭) of Yukjeollyeo(六節閭) in Hoengseong-gun and People of Yukjeol(六節) (횡성군 육절려(六節閭)의 정려표창 연기(年記)와 육절 대상인물 고찰)

  • Lee, Sang-kyun
    • Korean Journal of Heritage: History & Science
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    • v.47 no.2
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    • pp.20-31
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    • 2014
  • This thesis aims to how Seo Ye-won(徐禮元) who was the main character of Yukjeollyeo(六節閭) which means tangible cultural properties can receive Jeongnyeo(旌閭) and when he received it clearly. Also this thesis concentrates on why the name of 'Yukjeollyeo' was used even if there are five Jeongnyeos in the Yukjeollyeo. Lastly, this thesis also focuses on the people related to YookJeol. Seo Ye-won passed away with his family in 1593 when he acted as a head of local administration. In that time, the Jinjuseong(晉州城) battle was originated from Korea-Japan war(1592). After his death, Hoengseong(橫城) family(門中) and Confucian scholar made petition for administration in 1811. As a result Seo Ye-won and his wife Lady Lee of the Jeonju-Lee clan(全州李氏) were celebrated as the Jeongnyeo and Jeongyeogak was built in 1817. And his son(Seo Gye-seong:徐繼聖), Seo Gye-seong's wife Lady Noh of the Pungcheon-Noh clan(豊川盧氏), Seo Ye-won's daughter who were not married also could receive Jeongnyeo as Hoengseong family and confucian scholar made additional petition for administration in 1832. For these reasons, Jeongnyeogak(旌閭閣) was called 'Ojeongnyeo(五旌閭)'. After that, Miryang(密陽) family wanted to move it because Seon Ye-won is not the eldest son in the Hoengseoung family. But it could not be enforced and they made a new Yeokak(閭閣) and called 'Yukjeollyeo'. From that time to 1945, the name of Jeongnyeo in the Hoengseong had been still used 'OjeongYeo' and the signboard of Yukjeollyeo was hanged in Jeongnyeo in Hoengseong after 1945. Although there are five people who can get prize of Jeongnyeo, the reason why the name of 'YookJeol' is to memorize the loyalty of Seo Gye-cheol(徐繼哲) who was Seo Ye-won's second son. Hoengseong family made a representation to the government in order to made Seo Gye-cheol receive Jeongnyeo but he could not be celebrated. For these reasons, the loalty of Seo Gye-cheol with five people who received Jeongnyeo has been celebrated as 'YukJeol'. Through this study we could find the record of Yukjeollyeo and historic point clearly.

District 9 : Science Fiction as Social Critique (<디스트릭트 9> 사회비평으로서의 공상과학)

  • Cho, Peggy C.
    • Cross-Cultural Studies
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    • v.42
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    • pp.505-524
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    • 2016
  • This study examines the ways District 9, a film released in 2009, reworks the sci-fi genre to explore the human encounter with "other" alien populations. Like Avatar, released in the same year, District 9 addresses the tropes of conflict over land and human-alien hybridity and introduces non-humans and aliens, not as invaders, but as objects of human oppression and cruelty. Unlike many other science fiction films where the encounter between humans and non-humans occurs in an unidentifiable future time and location, District 9 crosses genre barriers to engage with urban realism, producing a social critique of contemporary urban population problems. The arrival of aliens in District 9 occurs as part of the recorded human past and the film's action is carried out in the present time in the specifically identified city of Johannesburg. A distinctly anti-Hollywood film that locates the action at the street level, District 9 plays out human anxieties about contact with others by referencing the divisions and conflicts historically attached to South Africa's sprawling metropolis and its current problems of urban poverty and illegal immigrants. Focusing on how this particular urban setting frames the film, the study investigates the ways Blomkamp's sci-fi film about extra-terrestrials presents a curious postcolonial mix of aliens and immigrants surviving in abject conditions in an urban slum and forces a realistic examination of the contemporary social problems faced by South Africa's largest city and by extension other major global cities. The paper also examines the film's representation of the human-alien hybrid and its potential as a force to resist human exploitation of the other. It also claims that though the setting is highly local, District 9 speaks to a wider global audience by making obvious the exploitative practices of profit-seeking multinationals. A sci-fi film that is keen on making a social commentary on urban population conflicts, District 9 resonates with the wider sense of insecurity and fear of others that form the horizon of the uncertain and potentially violent contemporary human world.

A Study on Setup for Preliminary Decision Criterion of Continuum Rock Mass Slope with Fair to Good Rating (양호한 연속체 암반사면의 예비 판정기준 설정 연구)

  • Kim, Hyung-Min;Lee, Su-gon;Lee, Byok-Kyu;Woo, Jae-Gyung
    • The Journal of Engineering Geology
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    • v.29 no.2
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    • pp.85-97
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    • 2019
  • It can be observed that steep slopes ($65^{\circ}$ to $80^{\circ}$) consist of rock masses were kept stable for a long time. In rock-mass slopes with similar ground condition, steeper slopes than 1 : 0.5 ($63^{\circ}$) may be applied if the discontinuities of rock-mass slope are distributed in a direction favorable to the stability of the slope. In making a decision the angle of the slope, if the preliminary rock mass conditions applicable to steep slope are quantitatively setup, they may be used as guidance in design practice. In this study, the above rock mass was defined as a good continuum rock mass and the quantitative setup criterion range was proposed using RMR, SMR and GSI classifications for the purpose of providing engineering standard for good continuum rock mass conditions. The methods of study are as follows. The stable slope at steep slopes ($65^{\circ}$ to $80^{\circ}$) for each rock type was selected as the study area, and RMR, SMR and GSI were classified to reflect the face mapping results. The results were reviewed by applying the calculated shear strength to the stable analysis of the current state of rock mass slope using the Hoek-Brown failure criterion. It is intended to verify the validity of the preliminary criterion as a rock mass condition that remains stable on a steep slope. Based on the analysis and review by the above research method, it was analyzed that a good continuum rock mass slope can be set to Basic RMR ${\geq}50$ (45 in sedimentary rock), GSI and SMR ${\geq}45$. The safety factor of the LEM is between Fs = 14.08 and 67.50 (average 32.9), and the displacement of the FEM is 0.13 to 0.64 mm (average 0.27 mm). This can be seen as a result of quantitative representation and verification of the stability of a good continuum rock mass slope that has been maintained stable for a long period of time with steep slopes ($65^{\circ}$ to $80^{\circ}$). The setup guideline for a good continuum rock mass slope will be able to establish a more detailed setup standard when the data are accumulated, and it is also a further study project. If stable even on steep slopes of 1 : 0.1 to 0.3, the upper limit of steep slopes is 1 : 0.3 with reference to the overseas design standards and report, thus giving the benefit of ensuring economic and eco-friendlyness. Also, the development of excavation technology and plantation technology and various eco-friendly slope design techniques will help overcome psychological anxiety and rapid weathering and relaxation due to steep slope construction.

A Study on the Online Newspaper Archive : Focusing on Domestic and International Case Studies (온라인 신문 아카이브 연구 국내외 구축 사례를 중심으로)

  • Song, Zoo Hyung
    • The Korean Journal of Archival Studies
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    • no.48
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    • pp.93-139
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    • 2016
  • Aside from serving as a body that monitors and criticizes the government through reviews and comments on public issues, newspapers can also form and spread public opinion. Metadata contains certain picture records and, in the case of local newspapers, the former is an important means of obtaining locality. Furthermore, advertising in newspapers and the way of editing in newspapers can be viewed as a representation of the times. For the value of archiving in newspapers when a documentation strategy is established, the newspaper is considered as a top priority that should be collected. A newspaper archive that will handle preservation and management carries huge significance in many ways. Journalists use them to write articles while scholars can use a newspaper archive for academic purposes. Also, the NIE is a type of a practical usage of such an archive. In the digital age, the newspaper archive has an important position because it is located in the core of MAM, which integrates and manages the media asset. With this, there are prospects that an online archive will perform a new role in the production of newspapers and the management of publishing companies. Korea Integrated News Database System (KINDS), an integrated article database, began its service in 1991, whereas Naver operates an online newspaper archive called "News Library." Initially, KINDS received an enthusiastic response, but nowadays, the utilization ratio continues to decrease because of the omission of some major newspapers, such as Chosun Ilbo and JoongAng Ilbo, and the numerous user interface problems it poses. Despite these, however, the system still presents several advantages. For example, it is easy to access freely because there is a set budget for the public, and accessibility to local papers is simple. A national library consistently carries out the digitalization of time-honored newspapers. In addition, individual newspaper companies have also started the service, but it is not enough for such to be labeled an archive. In the United States (US), "Chronicling America"-led by the Library of Congress with funding from the National Endowment for the Humanities-is in the process of digitalizing historic newspapers. The universities of each state and historical association provide funds to their public library for the digitalization of local papers. In the United Kingdom, the British Library is constructing an online newspaper archive called "The British Newspaper Archive," but unlike the one in the US, this service charges a usage fee. The Joint Information Systems Committee has also invested in "The British Newspaper Archive," and its construction is still ongoing. ProQuest Archiver and Gale NewsVault are the representative platforms because of their efficiency and how they have established the standardization of newspapers. Now, it is time to change the way we understand things, and a drastic investment is required to improve the domestic and international online newspaper archive.

A Study on the Memory of the Korean War and the Representation of the Play-Focused on Shin Myung-soon's (한국 전쟁에 대한 기억과 연극의 재현 양상 -신명순의 <증인>을 중심으로)

  • Kim, Tae-hee
    • (The) Research of the performance art and culture
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    • no.43
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    • pp.145-172
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    • 2021
  • Shin Myung-soon's is based on the taboo 'bombing of the Han River Bridge'. The reality of the bombing of the Han River Bridge in 1950 and the shooting of Colonel Choi Chang-sik was known only as a word of mouth. At that time, the ruling class did not want to reveal the painful mistakes of the unfavorable war situation in the early days of the war and the false broadcasting of the president. The truth of the case, which was kept completely secret even to the bereaved family, could only be revealed after the regime change. After that, the bereaved family of Colonel Choi Chang-sik confirmed the innocence of the deceased through a request for retrial, and then the was born. However, the fate of was not so smooth. At the time, the performance officials vividly remember the difficulties they had with the text. Despite passing the pre-screening of the script, the performance was canceled just before the performance. The fact that the National Theater, officials from the Ministry of Culture and Education, and even military generals visited the practice room to stop the performance, on the contrary, was a testimony to the dangers of . It can be summarized as a crack in official history and a move to stop it. was later adapted into a special TV drama in 1981 and was first released to the public. This was a very meaningful step in terms of dealing with politically sensitive subjects on television, but the inconsistency of in the first place has largely disappeared. After that, in 1988, only after democracy entered the phase of appeasement, could be performed in its full form. In short, can be said to be an example of a process in which the history of the Korean War recorded from the standpoint of an established order and the counter-memory that crack it up are transformed according to the changes of the times and media.

Memory Organization for a Fuzzy Controller.

  • Jee, K.D.S.;Poluzzi, R.;Russo, B.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.1041-1043
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    • 1993
  • Fuzzy logic based Control Theory has gained much interest in the industrial world, thanks to its ability to formalize and solve in a very natural way many problems that are very difficult to quantify at an analytical level. This paper shows a solution for treating membership function inside hardware circuits. The proposed hardware structure optimizes the memoried size by using particular form of the vectorial representation. The process of memorizing fuzzy sets, i.e. their membership function, has always been one of the more problematic issues for the hardware implementation, due to the quite large memory space that is needed. To simplify such an implementation, it is commonly [1,2,8,9,10,11] used to limit the membership functions either to those having triangular or trapezoidal shape, or pre-definite shape. These kinds of functions are able to cover a large spectrum of applications with a limited usage of memory, since they can be memorized by specifying very few parameters ( ight, base, critical points, etc.). This however results in a loss of computational power due to computation on the medium points. A solution to this problem is obtained by discretizing the universe of discourse U, i.e. by fixing a finite number of points and memorizing the value of the membership functions on such points [3,10,14,15]. Such a solution provides a satisfying computational speed, a very high precision of definitions and gives the users the opportunity to choose membership functions of any shape. However, a significant memory waste can as well be registered. It is indeed possible that for each of the given fuzzy sets many elements of the universe of discourse have a membership value equal to zero. It has also been noticed that almost in all cases common points among fuzzy sets, i.e. points with non null membership values are very few. More specifically, in many applications, for each element u of U, there exists at most three fuzzy sets for which the membership value is ot null [3,5,6,7,12,13]. Our proposal is based on such hypotheses. Moreover, we use a technique that even though it does not restrict the shapes of membership functions, it reduces strongly the computational time for the membership values and optimizes the function memorization. In figure 1 it is represented a term set whose characteristics are common for fuzzy controllers and to which we will refer in the following. The above term set has a universe of discourse with 128 elements (so to have a good resolution), 8 fuzzy sets that describe the term set, 32 levels of discretization for the membership values. Clearly, the number of bits necessary for the given specifications are 5 for 32 truth levels, 3 for 8 membership functions and 7 for 128 levels of resolution. The memory depth is given by the dimension of the universe of the discourse (128 in our case) and it will be represented by the memory rows. The length of a world of memory is defined by: Length = nem (dm(m)+dm(fm) Where: fm is the maximum number of non null values in every element of the universe of the discourse, dm(m) is the dimension of the values of the membership function m, dm(fm) is the dimension of the word to represent the index of the highest membership function. In our case then Length=24. The memory dimension is therefore 128*24 bits. If we had chosen to memorize all values of the membership functions we would have needed to memorize on each memory row the membership value of each element. Fuzzy sets word dimension is 8*5 bits. Therefore, the dimension of the memory would have been 128*40 bits. Coherently with our hypothesis, in fig. 1 each element of universe of the discourse has a non null membership value on at most three fuzzy sets. Focusing on the elements 32,64,96 of the universe of discourse, they will be memorized as follows: The computation of the rule weights is done by comparing those bits that represent the index of the membership function, with the word of the program memor . The output bus of the Program Memory (μCOD), is given as input a comparator (Combinatory Net). If the index is equal to the bus value then one of the non null weight derives from the rule and it is produced as output, otherwise the output is zero (fig. 2). It is clear, that the memory dimension of the antecedent is in this way reduced since only non null values are memorized. Moreover, the time performance of the system is equivalent to the performance of a system using vectorial memorization of all weights. The dimensioning of the word is influenced by some parameters of the input variable. The most important parameter is the maximum number membership functions (nfm) having a non null value in each element of the universe of discourse. From our study in the field of fuzzy system, we see that typically nfm 3 and there are at most 16 membership function. At any rate, such a value can be increased up to the physical dimensional limit of the antecedent memory. A less important role n the optimization process of the word dimension is played by the number of membership functions defined for each linguistic term. The table below shows the request word dimension as a function of such parameters and compares our proposed method with the method of vectorial memorization[10]. Summing up, the characteristics of our method are: Users are not restricted to membership functions with specific shapes. The number of the fuzzy sets and the resolution of the vertical axis have a very small influence in increasing memory space. Weight computations are done by combinatorial network and therefore the time performance of the system is equivalent to the one of the vectorial method. The number of non null membership values on any element of the universe of discourse is limited. Such a constraint is usually non very restrictive since many controllers obtain a good precision with only three non null weights. The method here briefly described has been adopted by our group in the design of an optimized version of the coprocessor described in [10].

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