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Studies on the Acute Toxicity of an Insecticide Cartap to Several Species of Freshwater Animals (몇가지 담수산동물(淡水産動物)에 대한 살충제 Cartap의 급성독성(急性毒性)에 관한 연구(硏究))

  • Byun, Sang-Ji;Choi, Seung-Yoon;Kim, Gwang-Po
    • Korean Journal of Environmental Agriculture
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    • v.3 no.2
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    • pp.43-49
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    • 1984
  • The acute toxicity of an insecticide cartap to several species of freshwater animals was evaluated in the laboratory with special reference to the species specificity, effects of water temperatures and pH values. The aquatic animals tested were the Carassius auratus L., Aphyocypris chinensis $G{\"{U}}NTHER$, Misgurus anguillicaudatus CANTOR, Moina macrocopa STRAUS. The susceptibility of aquatic animals to cartap was different with the species of animals. At the water temperature of $25^{\circ}C$ and pH 7, TLm values of the insecticide to the C. auratus L., A. chinensis G. and M. anguillicaudatus were 0.88, 0.26 and 0.13 ppm in 48 hours, respectively, and to Moina macrocopa S., 306 ppm in 3 hrs. In the case of the three species of fish, TLm 48 values were significantly decreased with rise in temperature. In the case of water flea, where TLm value was 107 ppm at $20^{\circ}C$, there was no consistent response to temperature change, with the highest figure at $25^{\circ}C$ than at either 20 or $30^{\circ}C$. and the susceptibility of C.auratus L. and A. chinensis G. greatly decreased with the increase of pH in water. The toxicity to M. anguillicaudatus and M. macrocopa was significantly higher at pH 9 than at pH 6 or 7. In conclusion, the toxicological reactions of the freshwater animals to cartap were variably influenced by the water temperatures and pH values of water and species of animals.

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An Analysis of the Roles of Experience in Information System Continuance (정보시스템의 지속적 사용에서 경험의 역할에 대한 분석)

  • Lee, Woong-Kyu
    • Asia pacific journal of information systems
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    • v.21 no.4
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    • pp.45-62
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    • 2011
  • The notion of information systems (IS) continuance has recently emerged as one of the most important research issues in the field of IS. A great deal of research has been conducted thus far on the basis of theories adapted from various disciplines including consumer behaviors and social psychology, in addition to theories regarding information technology (IT) acceptance. This previous body of knowledge provides a robust research framework that can already account for the determination of IS continuance; however, this research points to other, thus-far-unelucidated determinant factors such as habit, which were not included in traditional IT acceptance frameworks, and also re-emphasizes the importance of emotion-related constructs such as satisfaction in addition to conscious intention with rational beliefs such as usefulness. Experiences should also be considered one of the most important factors determining the characteristics of information system (IS) continuance and the features distinct from those determining IS acceptance, because more experienced users may have more opportunities for IS use, which would allow them more frequent use than would be available to less experienced or non-experienced users. Interestingly, experience has dual features that may contradictorily influence IS use. On one hand, attitudes predicated on direct experience have been shown to predict behavior better than attitudes from indirect experience or without experience; as more information is available, direct experience may render IS use a more salient behavior, and may also make IS use more accessible via memory. Therefore, experience may serve to intensify the relationship between IS use and conscious intention with evaluations, On the other hand, experience may culminate in the formation of habits: greater experience may also imply more frequent performance of the behavior, which may lead to the formation of habits, Hence, like experience, users' activation of an IS may be more dependent on habit-that is, unconscious automatic use without deliberation regarding the IS-and less dependent on conscious intentions, Furthermore, experiences can provide basic information necessary for satisfaction with the use of a specific IS, thus spurring the formation of both conscious intentions and unconscious habits, Whereas IT adoption Is a one-time decision, IS continuance may be a series of users' decisions and evaluations based on satisfaction with IS use. Moreover. habits also cannot be formed without satisfaction, even when a behavior is carried out repeatedly. Thus, experiences also play a critical role in satisfaction, as satisfaction is the consequence of direct experiences of actual behaviors. In particular, emotional experiences such as enjoyment can become as influential on IS use as are utilitarian experiences such as usefulness; this is especially true in light of the modern increase in membership-based hedonic systems - including online games, web-based social network services (SNS), blogs, and portals-all of which attempt to provide users with self-fulfilling value. Therefore, in order to understand more clearly the role of experiences in IS continuance, analysis must be conducted under a research framework that includes intentions, habits, and satisfaction, as experience may not only have duration-based moderating effects on the relationship between both intention and habit and the activation of IS use, but may also have content-based positive effects on satisfaction. This is consistent with the basic assumptions regarding the determining factors in IS continuance as suggested by Oritz de Guinea and Markus: consciousness, emotion, and habit. The principal objective of this study was to explore and assess the effects of experiences in IS continuance, with special consideration given to conscious intentions and unconscious habits, as well as satisfaction. IN service of this goal, along with a review of the relevant literature regarding the effects of experiences and habit on continuous IS use, this study suggested a research model that represents the roles of experience: its moderating role in the relationships of IS continuance with both conscious intention and unconscious habit, and its antecedent role in the development of satisfaction. For the validation of this research model. Korean university student users of 'Cyworld', one of the most influential social network services in South Korea, were surveyed, and the data were analyzed via partial least square (PLS) analysis to assess the implications of this study. In result most hypotheses in our research model were statistically supported with the exception of one. Although one hypothesis was not supported, the study's findings provide us with some important implications. First the role of experience in IS continuance differs from its role in IS acceptance. Second, the use of IS was explained by the dynamic balance between habit and intention. Third, the importance of satisfaction was confirmed from the perspective of IS continuance with experience.

Using Trophic State Index (TSI) Values to Draw Inferences Regarding Phytoplankton Limiting Factors and Seston Composition from Routine Water Quality Monitoring Data (영양상태지수 (trophic state index)를 이용한 수체 내 식물플랑크톤 제한요인 및 seston조성의 유추)

  • Havens, Karl E
    • Korean Journal of Ecology and Environment
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    • v.33 no.3 s.91
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    • pp.187-196
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    • 2000
  • This paper describes a simple method that uses differences among Carlson's (1977) trophic state index (TSI) values based on total phosphorus (TP), chlorophyll a (CHL) and Secchi depth (SD) to draw inferences regarding the factors that are limiting to phytoplankton growth and the composition of lake seston. Examples are provided regarding seasonal and spatial patterns in a large subtropical lake (Lake Okeechobee, Florida, USA) and inter- and intra-lake variations from a multilake data set developed from published studies. Once an investigator has collected routine water quality data and established TSI values based on TP, CHL, and SD, a number of inferences can be made. Additional information can be provided where it also is possible to calculate a TSI based on total nitrogen (TN). Where TSI (CHL)<>TSI (SD), light attenuating particles are large (large filaments or colonies of algae), and the phytoplankton may be limited by zooplankton grazing. Other limiting conditions are inferred by different relationships between the TSI values. Results of this study indicate that the analysis is quite robust, and that it generally gives good agreement with conclusions based on more direct methods (e.g., nutrientaddition bioassays, zooplankton size data, zooplankton removal experiments). The TSI approach, when validated periodically with these more costly and time-intensive methods, provides an effective, low cost method for tracking long-term changes in pelagic structure and function with potential value in monitoring lake ecology and responses to management.

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Monsoon Inflow as a Major Source of In-lake Phosphorus (호수내 인의 주요원으로 몬순 유입수)

  • An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.33 no.3 s.91
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    • pp.222-229
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    • 2000
  • Spatial and temporal variation of phosphorus in response to intensity of summer monsoon was evaluated in Taechung Reservoir during 1993${\sim}$1994. Total phosphorus (TP) averaged 31 ${\mu}$g/l during the study and varied from 6 to 197 ${\mu}$g/l. Concentrations of TP were highest in the headwaters during the monsoon of July${\sim}$August 1993, and these values were mainly made of particulate P and were closely associated (R$^{2}$=0.74, p<0.001) with high inorganic suspended solids (NVSS). In-lake TP in the headwaters was mainly influenced by the watershed runoff and declined toward the dam. Values of TP downlake was only one-fifth of the peak in the headwaters and had no correlation with NVSS. In 1994, inlake TP was markedly lower relative to 1993 and showed low spatial and temporal variation. Maximum TP during monsoon 1994 in the headwaters and mid-lake was 72% and 52% lower, respectively, than in those two zones in 1993 whereas TP downlake was similar between the two years. These results suggest that temporal variation downlake is much less influenced by seasonal inflow compared to the haedwaters. In 1993, mean TP before fall overturn, based on average value for all sites, was significantly (t=5.99, p<0.001) greater than the mean after fall overturn, whereas in 1994 mean TP after fall overturn (32 ${\mu}$g/l) was greater. This outcome indicates that in 1993 major P-input originated from the external source from the watershed during the intense monsoon, whereas in 1994 internal processes dominated during the weak monsoon. Overall data suggest that annual budget of inlake P is regulated by intensity of the summer monsoon, and phosphorus data measured at single site near the dam or headwater zone may not be represent seasonal trends of the system due to large spatial variation of Taechung Reservoir.

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Studies on the storage of fresh fruits and vegetables by plastic coating (1) on Rall's Janet Apple- (Plastic Coating에 의(依)한 청과물저장연구(靑果物貯藏硏究) (제1보(第1報)) -사과(국광(國光))에 대(對)하여-)

  • Park, Nou-Pung
    • Applied Biological Chemistry
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    • v.12
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    • pp.89-97
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    • 1969
  • These studies were made on coating of fresh fruits and vegetables with PVC under view on preservation of fresh fruits and vegetables due to restrain water evaporation of them and control gas metabolisms. The results obtained, as selection of PVC materials availble for preservation of them, procedure of the coating, useful organic solvents, concentration of PVC solution and the time of dipping, and effects of the preservation of them, were summarized as follows: 1) PVC powder 222 and PVC powder 443 were surveyed as suitable materials for coating apple, and later was excellent in lustrous aspect. 2) The coating procedure which dipt into PVC solution was suitable to treat much within a short space of time, and using of ventillator accelerate rather evaporation of the organic solvent. 3) Aceton and methyethylketon as solvent of the PVC were, in purpose of storage only, avaible, while aceton was, in view ef taste, better. 4) 10% of the PVC solutions were better to preserve the freshness of apple and 5, 4, 1 and 0.5% of them in order were gradually decreased in preservability, and 15% of them as high concentration were looked like fermentation in one week after the coating. 5) The dipping time was also better n minute than 10 seconds in a preservation but 1-2 minutes could be applied owing to be not affected of the taste due to coating. 6) The freshness of treatment groups were extend about 48 days after coating in room temperature but control lost market value with 12 days. 7) Weight of control was decreased to 10-13% but treatment which was dipped into 10% of coating solution for one minute was decreased to 3.5-4.6% and treatment for four minutes was did to 2.9-3.0%. 8) Change in respiration was less is treatment groups than control in exhaustion of $CO_2$, and water soluble sugar, reduced sugar and pH were not changed almost due to coating. 9) Pannel discussion of the taste was indicated that control was better than treatments soon after coating, but treatments were rather than control last period of storage and treatment with aceton solvent specially was better than others.

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The Electrochemical Chlorination for Marine Plankton Community Disinfection (해양 플랑크톤 군집의 전기분해 염소소독 효과)

  • Kang, Jung-Hoon;Shin, Kyoung-Soon;Hyun, Bong-Gil;Jang, Min-Chul;Kim, Eun-Chan;Chang, Man
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.10 no.3
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    • pp.127-137
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    • 2007
  • To confirm whether or not the Electrochemical Disinfection System (EDS) meet with the D-2 regulation established by IMO (International Maritime Organization), the biological treatment efficacy of the EDS was assessed using three groups of natural marine plankton (bacteria, $10-50\;{\mu}m$ and $>50\;{\mu}m$ sized organisms). Influent water was passed through the EDS under the flow velocity ($23.8\;m^3/hr$) and test design was consisted of control (no treatment) and experimental (10 ppm and 30 ppm) condition for total residual chlorine (TRC). And the biological condition of the influent water followed the standards established by the guidelines for the approval of ballast water management systems. The disinfection efficacy of the $10-50\;{\mu}m$ sized organisms (phytoplankton) was assessed by three kinds of measurements using photomicroscope, epifluorescence microscope and fluorometer (fumer Designs 10-AU). After being passed through the EDS, all motile phytoplankton lost their motility under photomicroscope, the colour of chlorophyll fluorescence fumed from red into green under epifluorescence, and the high chlorophyll fluorescence (Expt. 1: 6.95, Expt. 2: 7.11) detected by fluorometer decreased into value not detected. These results indicated phytoplankton community was totally killed after electrochemical disinfection treatment. Survivorship of the larger organisms than $50\;{\mu}m$ was determined based on the appendage's movement under a stereomicroscope. Natural assemblage collected from ambient seawater was killed shortly after being passed through the EDS, whereas some Artemia remained alive. However, no live Artemia was found after 24 hour further exposure to each TRC concentration (10 and 30 ppm) under darkness. After electrochemical treatment, the target bacteria such as aerobes, coliform and Escherichia coli were completely killed on the basis of CFU (colony forming unit) on Petrifilm plate ($3\;M^{TM}$) after 48 hr incubation. Moreover, no regrowth was found in the three groups of plankton during five days under additional exposure to the treated water. These results indicated that the disinfection efficiency of the EDS on the three groups of plankton satisfy D-2 regulation.

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Abstracting Services in Korea (한국의 초록서비스에 대하여)

  • Choi Sung-Jin
    • Journal of the Korean Society for Library and Information Science
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    • v.24
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    • pp.9-51
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    • 1993
  • The purpose of this study is twofold: to investigate into general characteristics of the abstracting services in Korea and to discuss general directions of development of the abstracting services in the country. This study is designed to achieve the purpose by gathering and analysing data related to the abstracting journals published in the past ten years and by comparing the results with similar data gathered by the investigator in 1984. The major conclusions made in this study is summarised as follows. (1) Researchers and professionals working in limited numbers of subject fields are benefited by abstracting services of recent achievements in research and development in Korea. Those in most of the fields have essentially no abstracting services of such achievements. Even many researchers and professionals in the limited numbers of the fields that have some elementary abstracting services are not informed of research results in their fields because the abstracting journals are scattered in many narrow subjects and in many cases, the abstracting journals only cover publications in some specific forms and kinds. (2) Abstracting journals of general subjects, which are supposed to be of more or less help to the researchers in the subject fields that have no abstracting journals of their own, have rapidly increased in number in the past ten years. Most of such abstracting journals carry thesis and dissertation abstracts, and the rest those of research papers published in specific places, in specific forms, by specific institutes, and of reports of research projects sponsored by specific foundations. These abstracting journals are not of the kind that comprehensively provide general readers with current awareness of publications of research results in Korea. (3) Most of the abstracting journals existing in Korea are published by institutions of higher education and research institutes, and the rest by commercial publishers, industrial firms, libraries, information centers, government agencies, research foundations, learned societies, etc. Those which publish many titles are small in number and those publish one or two titles are large in number. The former is largely made up of institutions of higher education and research institutes. (4) Ten years ago, there was not a single publishing house that produced abstracting journals. Three commercial publishing houses now produce abstracting journals. As this change occurs, centers of excellence are founded and competitive elements are introduced in abstracting services. This change, in turn, is expected to improve quality of the other abstracting journals in Korea. (5) The abstracting journals published in Korea are classified by type into those of dissertations, research papers, journal articles, patent specifications in that descending order. The fact that Master's and doctoral dissertation abstracts are dominating in Korea is due to the irrational practice of publishing those abstracts at many institutions. (6) Most of the abstracting journals existing in Korea are published by national or government-supported research institutes in order to publicise their own research outputs. Their coverage of literature is normally narrow, and naturally their value to users is limited. (7) The abstracting journals published in Korea increased in number at the rate of $77.8-100\%$ every five years in the past twenty-five years. Most of the abstracting journals that ceased to be published during the period survived for two years. (8) Korean is the desirable language for the abstracting journals designed to be distributed within Korea. About half of the abstracting journals published in Korea is printed in Korean and the other half in foreign languages, and in Korean with foreign languages. All the abstracting journals in foreign languages are printed in English xcept one, which is printed in Japanese. (9) Some twenty percent of the abstracting journals in Korea is published monthly, bimonthly, and quarterly. Others are published annually, biannually, and irregularly. The latter may not function properly as a current-awareness tool due to long intervals between their issues. It is particularly undesirable that about half of the abstracting journals in Korea is published irregularly. Most of the abstracting journals published in Korea are distributed freely to individuals and institutions selected by the publishers. (10) The abstracting journals published by the use of computers increased drastically in the past ten years. The abstracting journals produced by the conventional type-setting method will probably disappear In Korea in another ten years to come. Automation of the production of abstracting journals does not simply mean technical, economic improvement of publishing processes but availability of machine-readable databases that can be used for other purposes, including the generation of other publications and the provision of machine literature searching capabilities. Necessary steps should be taken for this important development that is occurring in the abstracting services in Korea.

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Vietnamese Immigrants and Buddhism in Southern Louisiana: Ingredients for 'Melting Pot' or for Cultural Diversity? (남부루이지애나의 베트남 移民集團과 佛敎: 鎔鑛爐 속의 成分? 혹은 文化的 多樣性의 成分?)

  • Lee, Young-Min
    • Journal of the Korean Geographical Society
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    • v.31 no.4
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    • pp.685-698
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    • 1996
  • Southern Louisiana has one of the largest Vitnamese refrgee neighborhoods after the mid-1970s. It is impressive that one of their adaptive strategies comes from their religious lives which are centered on either Catholicism or Buddhism. The Buddhism community, especially, exhibits an exotic symbolic system of value and attitude, and thus contributes to cultural diversity in the adopted country. The landscape of the Buddhist temple is a visible symbol to them that the host socirty accepts their maintenance of their own cultural identity and that they are also an integral part of American society. Their making-place and being-in-place procedures, although their culture is being transformed in the original shape, put an emphasis on interaction with the host xociety. These procedures have been facilitated by consolidating their identity as a minority group as well as by interacting with the host society. The on-going influx of foreign immigrant groups seems not to drive them to assimilate into the melting-pot society, but to contribute to contribute to the increase in the cultural diversity of the United States.

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Component and Quality Characteristics of Powdered Green Tea Cultivated in Hwagae Area (화개지역 녹차분말의 성분 분석 및 품질특성)

  • Park Chan-Sung
    • Food Science and Preservation
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    • v.12 no.1
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    • pp.36-42
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    • 2005
  • The purpose of this study was to investigate the component and quality characteristics of green tea. Four kinds of green tea powder obtained from Hwagae area were evaluated the component of carbohydrates, protein crude fat and crude ash. Also the content of ascorbic acid, minerals and polyphenols in green tea powder were evaluated. Quality characteristics of green tea powder was evaluated by Hunter's colur value and sensory evaluation. Green tea was composed of $9.2\~11.8\%$ of moisture, $4.9\~6.1\%$ of crude ash, $5.2\~6.1\%$ of crude fat, $22.5\~26.4\%$ of protein and $50.4\~55.1\%$ of cabohydrates. The content of total ascorbic acid in green tea powder was $312\~392mg/100g$ and dehydiuascorbic acid was $157\~176mg/100g$. The contents of minerals in green tea powder sodium was $340\~580mg/100g$, magnesium was $242\~320mg/100g$, potassium $223\~278mg/100g$ me calcium $145.7\~238.7mg/100g$. Polyphenol content of green tea powder was $7.8\~9.3\%$ which was the highest in A and the lowest in B. Hunters color values of green tea, lightness(L) was $52.3\~69.6$, redness(a) was $0.11\~-5.61$, yellowness(b) was $14.23\~23.34$, which were better in green tea C and D than green tea A and B. From sensory evaluation of green tea powders, green tea D obtained the significant highest scores in color, flavor and overall quality(p<0.05) and followed by green tea C, Green tea powder C and D which have high levels of protein and ascorbic acid were evaluated as good quality in color and sensory evaluation.

Increase of Spoken Number of Syllables Using MIT(Melody Intonation Therapy) : Case Studies on older adult with stroke and aphasia (MIT(Melodic Intonation Therapy) 중심의 음악활동을 이용한 실어증을 가진 뇌졸중 노인의 음절 수 증가에 대한 사례 연구)

  • Hong, Do Kyoung
    • Journal of Music and Human Behavior
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    • v.2 no.2
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    • pp.57-67
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    • 2005
  • Most of stroke patients have not only physical difficulty but speech and neurological disorder because of hemiplegia and such unexpected changes cause psychologic disadaptability and absent-mindedness. Particularly, lowering of physical ability can lead to serious emotional problem from failure or frustration in daily life. Generally, treatment of patient with stroke put emphasis on physical rehabilitation but actually this patient had considerable speech disorder such as aphasia or articulation disorder. Moreover, failing of recognition function, mental disorder as hypochondria, and even visual and auditory disorder are represented. So it is effective to integrate verbal remediation and other treatments in medical care environment. In particular, patients with language disorder very often wither psychologically therefore it is efficient to use of music therapy that gives opulent emotion to aphasia patients. And primarily to investigate the effects of 10 sessions treatments; change in spoken total number of syllables, to confirm their own value by success of given task and reassure about themselves ability. All of 10 sessions stages were scored by MIT manual and its improvement were measured, that is, accomplishment was analyzed within each level in order to prove detail change of spoken total number of syllables. The result of this program organized from 2 syllables to 4 syllables is summarized as follows. Subject A completed in preliminary stage Level I, in 2 syllables case advanced to Level III in fifth session and to Level IV in seventh session, in 3 syllables case advanced to Level III in seventh session and to Level IV in ninth session, and in 4 syllables case showed 8% low success rate in first session but after repeated practice increased considerably in sixth session and in advanced to Level III in eighth session to Level IV in tenth session. Subject B also completed in preliminary stage Level I, in 2 syllables case advanced to Level III in forth session and to Level IV in sixth session, in 3 syllables case advanced to Level III in fifth session and to Level IV in seventh session, and in 4 syllables case showed 10% low success rate in first session and increased considerably in fifth session and in advanced to Level III in seventh session but could not reach to Level IV until tenth session. As a result, it was shown that music therapy using MIT was not statistically meaningful but improved spoken total number of syllables and success rate of task had improved as a whole. Therefore, music intervention using MIT it has positive affect on verbal ability of patients with Broca's Aphasia and their language rehabilitation.

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