• 제목/요약/키워드: Measure Development

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A Study on the Characteristics of Enterprise R&D Capabilities Using Data Mining (데이터마이닝을 활용한 기업 R&D역량 특성에 관한 탐색 연구)

  • Kim, Sang-Gook;Lim, Jung-Sun;Park, Wan
    • Journal of Intelligence and Information Systems
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    • v.27 no.1
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    • pp.1-21
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    • 2021
  • As the global business environment changes, uncertainties in technology development and market needs increase, and competition among companies intensifies, interests and demands for R&D activities of individual companies are increasing. In order to cope with these environmental changes, R&D companies are strengthening R&D investment as one of the means to enhance the qualitative competitiveness of R&D while paying more attention to facility investment. As a result, facilities or R&D investment elements are inevitably a burden for R&D companies to bear future uncertainties. It is true that the management strategy of increasing investment in R&D as a means of enhancing R&D capability is highly uncertain in terms of corporate performance. In this study, the structural factors that influence the R&D capabilities of companies are explored in terms of technology management capabilities, R&D capabilities, and corporate classification attributes by utilizing data mining techniques, and the characteristics these individual factors present according to the level of R&D capabilities are analyzed. This study also showed cluster analysis and experimental results based on evidence data for all domestic R&D companies, and is expected to provide important implications for corporate management strategies to enhance R&D capabilities of individual companies. For each of the three viewpoints, detailed evaluation indexes were composed of 7, 2, and 4, respectively, to quantitatively measure individual levels in the corresponding area. In the case of technology management capability and R&D capability, the sub-item evaluation indexes that are being used by current domestic technology evaluation agencies were referenced, and the final detailed evaluation index was newly constructed in consideration of whether data could be obtained quantitatively. In the case of corporate classification attributes, the most basic corporate classification profile information is considered. In particular, in order to grasp the homogeneity of the R&D competency level, a comprehensive score for each company was given using detailed evaluation indicators of technology management capability and R&D capability, and the competency level was classified into five grades and compared with the cluster analysis results. In order to give the meaning according to the comparative evaluation between the analyzed cluster and the competency level grade, the clusters with high and low trends in R&D competency level were searched for each cluster. Afterwards, characteristics according to detailed evaluation indicators were analyzed in the cluster. Through this method of conducting research, two groups with high R&D competency and one with low level of R&D competency were analyzed, and the remaining two clusters were similar with almost high incidence. As a result, in this study, individual characteristics according to detailed evaluation indexes were analyzed for two clusters with high competency level and one cluster with low competency level. The implications of the results of this study are that the faster the replacement cycle of professional managers who can effectively respond to changes in technology and market demand, the more likely they will contribute to enhancing R&D capabilities. In the case of a private company, it is necessary to increase the intensity of input of R&D capabilities by enhancing the sense of belonging of R&D personnel to the company through conversion to a corporate company, and to provide the accuracy of responsibility and authority through the organization of the team unit. Since the number of technical commercialization achievements and technology certifications are occurring both in the case of contributing to capacity improvement and in case of not, it was confirmed that there is a limit in reviewing it as an important factor for enhancing R&D capacity from the perspective of management. Lastly, the experience of utility model filing was identified as a factor that has an important influence on R&D capability, and it was confirmed the need to provide motivation to encourage utility model filings in order to enhance R&D capability. As such, the results of this study are expected to provide important implications for corporate management strategies to enhance individual companies' R&D capabilities.

A Study of Mac(脈)-Theory and Change of Mac(脈)-Diagnosis in Whang Di Nei Qing(黃帝內經) (황제내경(黃帝內經)의 맥(脈) 이론(理論)과 진맥법(診脈法)의 변화(變化)에 관(關)한 연구(硏究))

  • Ra, Kyoung-Chan;Park, Hyun Kook
    • The Journal of Dong Guk Oriental Medicine
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    • v.2 no.1
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    • pp.73-105
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    • 1993
  • To say nothing of the orient and the west, the human beings discover the method of Jin Mac(診脈) by the way that observe disease. But oriental medicine devise special method of Jin Mac(診脈) in the study of Kyoung Mac(經脈). Although sip-ei Kyoung Mac Jin(十二經脈診), Sam Bu Gu Who Jin(三部九候診), In Young Mac Gu Jin(人迎脈口診), Chon Kwan Chuck Jin(寸關尺診) namely Yuk Bu Jung Wee Jin Mac (六部定位診脈) that is used today are devised, it has changed naturally by the changing treatment and the introduction of Yuin Yang(陰陽) and five element(五行). Many methods dg Jin Mac(診脈), it had not developped successing alternative, it had developped of declined by it's own way. 1. Results for the birth of Mac(脈) 1) Mac(脈), it means Kyoung Mac(經脈), at first entirelly Mac(脈), is seized a blood vessel that flows in the body. As presumed today, after finding many acupunture point, a general idea of Mac(脈) is not maked by the line that connect point and point, it connect between acupunture point and acupunture point. 2) Like blood flows in Hyul Mac(血脈), Gie(氣) flows in Kyoung Mac(經脈). The two things relate deeply each other. In a general idea or actrally Kyoung Rak(經洛), the two things sometimes accord, sometimes seperate, sometimes mix alternative. 3) Hyul Mac(血脈) and Kyoung Mac(經脈), we call it Mac(脈) entirely Kyoung Mac(經脈), is a way that manifest disease through Kyoung Mac(經脈) or a boundary that disease belongs to it method of Mac Jin(脈診) individual that disease of Kyoung Mac(經脈) is diagnosed by the jumping situation of Hyul Mac(血脈). 4) In method of Moxa, athough the pathology and the diagnostic of Mac(脈) are created by finding Mac(脈). Finding acupunture have opportunitty fot Mac Jin(脈診) and treatment. 2. Results of Kyoung Mac Mac Jin(經脈脈診) 1) In theory of kyoung Rak(經洛), disease are resumed for malfunction of Young Wee(榮衛) that flows in Kyung Rak(經洛). So to speak, in treatment of Kyoung Rak area, the purpose of diagnosis observe the situation of disease and cause. For fitting the purpose of diagnosis, the dead had esatablised four-diagnosis method mangMunMnnJeul(望聞問切), in four-diagnosis(四診法), the core is Mac Jin(脈診). 2) sip-ei Kyoung Mac Mac Jin(十二經脈診) had existed as Kyoung Mac Mac Jin(經脈脈診), it precedes Sam Bu Gu Who Jin(三部九候診). In Young Ki Gu Mac(人迎脈口診). 3) Although Bu Yang Mac(趺陽脈), So Um Mac(少陰脈) is a part of Sip-ei Kyoung Mac(十二經脈診), they developped especially because they located in the point of Won Hyul(原穴) and they are convenient for diagnose. 4) Sip-ei Kyoung Mac Mac Jin(十二經脈診), which belongs to Bu Yang Mac(趺陽脈) and So Urn Mac(少陰脈), is not important for the comming age medical books compared with Mac Kyoung(脈經). 3. Results gor Sam Bu Gu Who Jin(三部九候診) 1) Mac Jin(脈診) of Sam Bu Gu Who(三部九候), which is noted in the theory of Sam Bu Gu Who(三部九候診) of So Mun(素問), belongs to Kyoung Mac Mac Jin's(經脈脈診) geneology, Sip-ei Kyoung Mac Mac Jin(十二經脈診) is arranged, simplicated by the idealogy three talents(三才思想) in the heaven and the earth. 2) What Sam Bu Gu Jin(三部九候診) is regardded as very important in So Mun(素問), the editor of So Mun(素問) recognize the meaning that one discover disease early in this method of diagnosis. 3) After Young chu(靈樞), Nan Kyoung(難經) it is lacked the method of Sam Bu Gu Who Jin(三部九候診) in the books that treatment has changed. Sam Bu Gu Who Jin(三部九候診) based on actually clinic appropriate. 4. results for In Young Mac Gu Jin(人迎脈口診) 1) In Young Mac Gu Jin(人迎脈口診) is the method of comparative Mac Jin(脈診) according to the theory of Yin Yang(陰陽), it is presumed after Sam Bu Gu Who Jin(三部九候診), it had perished in parallel with the development of the theory of five elelment(五行). The development of the acupunture, the perishment of the treatment of negative(刺絡). 2) In Young Mac Gu Jin(人迎脈口診), Wang Suk Wha(王叔和) recreated that the left is In Young(人迎), the right is Kie Gu(氣口). In future generations by Jin Mu Taek(陳無擇) who is the writer of Sam In Bang(三因方). In Young Mac Gu Jin(人迎脈口診) is a measure for disease which classify it's inside and outside cause. 5. Results for Chon Gu Mac Jin(寸口脈診) 1) What we say Mac Jin(脈診) of Chon Gu(寸口) two means are used in commn. First case, we simply say the area of Chon Gu(寸口), second case, we say Chon Kwan Chuk Jin(寸口尺診) reducingly. Chon Gu(寸口) is the area which is the radial artery of wrist joint. What we attemp diagnose by only Chon Gu Mac(寸口脈), it is clearly shoued in the method of Nan Kyoung, five Nan(難經五難). 2) Because Jin Mac(診脈) is made in only Chon Gu(寸口), that is the area in which is concentated Kyoung Kee(經氣). That is the birth of Jin Kee(眞氣) and Jin Kee(眞氣) is related with disease. We can diagnose disease by taking Chon Gu(寸口). 3) Chuk Jin(尺診) in Nae Kyoung(難經) have two things. One is Il Chuk(一尺), the other is Chon Kwan Chu(寸關尺). 4) Chuk Chon Jin(尺寸診) is the method which diagnose the difference of point and the condition of Mac(脈) by dividing a part of Chuk(尺) in the area of Chon Gu(寸口). In Chon Gu Jin(寸口診), by introducing the theory of Yin Yang(陰陽), the method of Chon Gu Jin(寸口診) is developed by chon Gu Jin(寸口診). 5) What Chuk Kwan Chon Jin(寸關尺診) is that area of the Chon Gu(寸口) are divided fot three point, we can diagnose. By consulting Sam Bu Gu Who Jin(三部九候診), developping of the method of acupunture, utilzing the theory of five element(五行) it is devised by concentrating way of thinking of the method mac Jin(脈診) exiting. 6) Chon Kwan Chuk Jin MaC(寸關尺診脈) begin from Nae Kyoung(內徑) exiting. After Nan Kyoung(內徑), spread out widely from Mac Kyoung(脈診) of Wang Suk wha(王叔和), the future medicins followed it. Yang Hyun Jo(楊玄操) and established Chon Kwan Chuk Jin(寸關尺診) which is used widely today. This right and left Chon Kwan Chuk Jin(寸關尺診), we call it method of Yuk Bu Jung Wee Jin Mac(六部定位診脈). 7) We can think the base which presume the arrangement of the viscera for Chon Kwan Chuk(寸關尺) of the right and the left. 8) The origin, which seperate the right and the left of Mac(脈), is showed at the treory of Ji Jin Yo Dae(至眞要大論) in So Mun(素問) which Chon Chuk(寸尺) seperate the right and the left. But the method of diagnosis in Nan Kyoung(難經) have no seperation the fight and the left. Otherwise this. there is clearly writtened the seperation for the right origin of the method of Yuk Bu Jung Wee Jin Mac(六部定位診脈) seek for Cang Gong(倉公). 9) Yang Hyun Jo(楊玄操) notice that the Chuk(尺) is mentioned for Sam Cho(三焦) in the method of Mac Kyuong(脈經), Sim Po Kyung(心包經) which put together with Sam Cho(三焦) allot on this, he had established the method of Yuk Bu Jung Wee Jin Mac(六部定位診脈). 10) On the method of Paen Jak Yin Yang Mac(扁鵲陰陽脈) in Mac Kyoung(脈經), equal article exist with the theory of Pyung In Kee Sang(平人氣象論) in So Mun(素問). When Wang Suk Wha(王叔和) write Mac Kyung(脈經), we can presume that the book of Mac(脈) which Paen Jak(扁鵲) had experienced the origin have exited besides So Mun(素問), Young Chu(靈樞). If so he must be make Chon Kwan Chuk Jin(寸關尺診) very fairly standard. So Nae Kyoung(內經), which must be fllowed the method of Paen Jak Mac(扁鵲脈), do the method diagnosis of Chon Kwan Chuk(寸關尺), diagnise of disease and treat.

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Halitosis and Related Factors among Rural Residents (농촌지역 주민들의 구취실태와 유발요인)

  • Lee, Young-Ok;Hong, Jung-Pyo;Lee, Tae-Yong
    • Journal of Oral Medicine and Pain
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    • v.32 no.2
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    • pp.157-175
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    • 2007
  • This study was conducted through an interview process in which questionnaires were administered to 293 people. The questionnaires related to the behaviors of oral hygiene care, and disease history related to halitosis, and status of halitosis, halitosis measurement, oral examination, and caries activity tests such as the snyder test, Salivary flow rate test, and Salivary buffering capacity test. Our sample was taken from 293 rural residents within the period from 4th to 21st of January 2006. This was done in order to provide basic data to prepare both policies of halitosis prevention and a device to efficiently measure halitosis status and investigate the factors related therein. The major findings of this study results are as follows: 1. As for frequency of tooth brushing, twice a day occupied the greatest portion at 46.1 % Women exceeded men in frequency of tooth brushing. Tongue brushing everyday produced a 25.6 % result among subjects and The use of auxiliary oral hygiene devices occupied 9.2 %. 2. As for degree of usual self-awareness of halitosis: 62.5 %. This result also demonstrate that the severest time of self-awareness in regards to halitosis is wake up time in the morning. The time period produced the highest portion of 72.7 % in times of self-awareness. In terms of the area in which halitosis was observed, gum resulted in 23.0 %. As for types of halitosis, fetid smell was the most frequent at 37.2 %. 3. As for the result of halitosis measurement, values of OG less than 50 ppm occupied 54.3 % and $50{\sim}100ppm$ occupied 41.6 %. As for $NH_3$ values, $20{\sim}60ppm$ showed the highest value range of 52.6 %. 4. As for OG per disease history related to halitosis, values of OG were significantly high in the ranges of $50{\sim}100ppm$ within family history groups of food impaction by dental caries, diabetes mellitus and halitosis. As for values of $NH_3$, there showed a significant difference in respiratory system disease groups. 5 Value range of OG per ordinary halitosis self-awareness degree: values ranging less than 50 ppm were recorded at 55.9 % from the group realizing not aware of smell. 57.5 % from groups only realizing sometimes, while values range of $50{\sim}100ppm$ were recorded at 52.0 % from groups always aware of smell. 63.6 % from groups always strongly aware of smell. Meanwhile as for the values ranges of $NH_3$, $20{\sim}60ppm$. they occupied high portions for all groups of exams. 6. Values of OG per oral examination: the more pulp-exposed teeth and food impaction and the higher the tongue plaque index, values of OG increased within the range of $50{\sim}100ppm$. As for values of $NH_3$, the more prosthetic teeth and the higher the tongue plaque index, this value increased significantly, and the values increased up to no less than 60 ppm for groups of mandibular partial denture. 7. Within the realm of caries activity test: as for the Snyder test, high activity was highest by 43.0 % wherewith the higher the activity of acidogenic bacteria the higher the OG values. As for the salivary flow rate test, the number of cases below 8.0 ml showed the highest tendency by 62.5 %. The larger the salivary flow rate the more decreased OG values distribution. As for the salivary buffering capacity test, $6{\sim}10$ drops of 0.1N lactic acid showed the overwhelming trend by 58.7 % whereby the higher the salivary buffering capacity the greater distribution occupancy ratio of OG values below 50 ppm which is scentless to on ordinary person. 8. As for the correlation between oral environment and halitosis, OG showed the positive correlation with pulp exposed teeth, filled teeth, present teeth, tongue plaque index, and food impaction, while the negative correlation with salivary flow rate and prosthetic teeth. $NH_3$ showed a positive correlation with prosthetic teeth and frequency of tooth brushing, while decayed teeth was negative correlation. 9. As for the multiple regression analysis result, there have been selected female, pulp exposed teeth, prosthetic teeth, food impaction, salivary flow rate, tongue plaque index and severe activities in the Snyder test as factors affecting OG wherein explanatory power on it was 45.1 %. There have been selected females, pulp exposed teeth, tongue plaque index, and prosthetic teeth as factors affecting on $NH_3$ wherein explanatory power on it was 6.6 %. With the aforementioned results in mind, the status of halitosis among rural residents is considered to bare a close relation with oral environments and other factors related to halitosis such as the Snyder test from caries activity test, and salivary flow rate test. For the prevention of halitosis of residents in rural areas, we have to focus on correct tooth brushing methods and tongue brushing, with using auxiliary oral hygiene devices to remove fur of tongue plaque and food impaction. Also, when the cause and ingredients of halitosis are diverse and complex, in order to analyze exactly the factors of individual halitosis development, we need continuous and systematic study in order to provide rural residents with programs of oral hygiene education and encourage the use of dental hygienists in public health centers.

The Influence of Store Environment on Service Brand Personality and Repurchase Intention (점포의 물리적 환경이 서비스 브랜드 개성과 재구매의도에 미치는 영향)

  • Kim, Hyoung-Gil;Kim, Jung-Hee;Kim, Youn-Jeong
    • Journal of Global Scholars of Marketing Science
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    • v.17 no.4
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    • pp.141-173
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    • 2007
  • The study examines how the environmental factors of store influence service brand personality and repurchase intention in the service environment. The service industry has been experiencing the intensified competition with the industry's continuous growth and the influence from rapid technological advancement. Under the circumstances, it has become ever more important for the brand competitiveness to be distinctively recognized against competition. A brand needs to be distinguished and differentiated from competing companies because they are all engaged in the similar environment of the service industry. The differentiation of brand achievement has become increasingly important to highlight certain brand functions to include emotional, self-expressive, and symbolic functions since the importance of such functions has been further emphasized in promoting consumption activities. That is the recent role of brand personality that has been emphasized in the service industry. In other words, customers now freely and actively express their personalities or egos in consumption activities, taking an important role in construction of a brand asset. Hence, the study suggests that it is necessary to disperse the recognition and acknowledgement that the maintenance of the existing customers contributes more to boost repurchase intention when it is compared to the efforts to create new customers, particularly in the service industry. Meanwhile, the store itself can offer a unique environment that may influence the consumer's purchase decision. Consumers interact with store environments in the process of,virtually, all household purchase they make (Sarel 1981). Thus, store environments may encourage customers to purchase. The roles that store environments play are to provide informational cues to customers about the store and goods and communicate messages to stimulate consumers' emotions. The store environments differentiate the store from competing stores and build a unique service brand personality. However, the existing studies related to brand in the service industry mostly concentrated on the relationship between the quality of service and customer satisfaction, and they are mostly generalized while the connective studies focused on brand personality. Such approaches show limitations and are insufficient to investigate on the relationship between store environment and brand personality in the service industry. Accordingly, the study intends to identify the level of contribution to the establishment of brand personality made by the store's physical environments that influence on the specific brand characteristics depending on the type of service. The study also intends to identify what kind of relationships with brand personality exists with brand personality while being influenced by store environments. In addition, the study intends to make meaningful suggestions to better direct marketing efforts by identifying whether a brand personality makes a positive influence to induce an intention for repurchase. For this study, the service industry is classified into four categories based on to the characteristics of service: experimental-emotional service, emotional -credible service, credible-functional service, and functional-experimental service. The type of business with the most frequent customer contact is determined for each service type and the enterprise with the highest brand value in each service sector based on the report made by the Korea Management Association. They are designated as the representative of each category. The selected representatives are a fast-food store (experimental-emotional service), a cinema house (emotional-credible service), a bank (credible-functional service), and discount store (functional-experimental service). The survey was conducted for the four selected brands to represent each service category among consumers who are experienced users of the designated stores in Seoul Metropolitan City and Gyeonggi province via written questionnaires in order to verify the suggested assumptions in the study. In particular, the survey adopted 15 scales, which represent each characteristic factor, among the 42 unique characteristics developed by Jennifer Aaker(1997) to assess the brand personality of each service brand. SPSS for Windows Release 12.0 and LISREL were used in the analysis of data verification. The methodology of the structural equation model was used for the study and the pivotal findings are as follows. 1) The environmental factors ware classified as design factors, ambient factors, and social factors. Therefore, the validity of measurement scale of Baker et al. (1994) was proved. 2) The service brand personalities were subdivided as sincerity, excitement, competence, sophistication, and ruggedness, which makes the use of the brand personality scales by Jennifer Aaker(1997) appropriate in the service industry as well. 3) One-way ANOVA analysis on the scales of store environment and service brand personality showed that there exist statistically significant differences in each service category. For example, the social factors were highest in discount stores, while the ambient factors and design factors were highest in fast-food stores. The discount stores were highest in the sincerity and excitement, while the highest point for banks was in the competence and ruggedness, and the highest point for fast-food stores was in the sophistication, The consumers will make a different respond to the physical environment of stores and service brand personality that are inherent to the corresponding service interface. Hence, the customers will make a different decision-making when dealing with different service categories. In this aspect, the relationships of variables in the proposed hypothesis appear to work in a different way depending on the exposed service category. 4) The store environment factors influenced on service brand personalities differently by category of service. The factors of store's physical environment are transferred to a brand and were verified to strengthen service brand personalities. In particular, the level of influence on the service brand personality by physical environment differs depending on service category or dimension, which indicates that there is a need to apply a different style of management to a different service category or dimension. It signifies that there needs to be a brand strategy established in order to positively influence the relationship with consumers by utilizing an appropriate brand personality factor depending on different characteristics by service category or dimension. 5) The service brand personalities influenced on the repurchase intention. Especially, the largest influence was made in the sophistication dimension of service brand personality scale; the unique and characteristically appropriate arrangement of physical environment will make customers stay in the service environment for a long time and will lead to give a positive influence on the repurchase intention. 6) The store environment factors influenced on the repurchase intention. Particularly, the largest influence was made on the social factors of store environment. The most intriguing finding is that the service factor among all other environment factors gives the biggest influence to the repurchase intention in most of all service types except fast-food stores. Such result indicates that the customers pay attention to how much the employees try to provide a quality service when they make an evaluation on the service brand. At the same time, it also indicates that the personal factor is directly transmitted to the construction of brand personality. The employees' attitude and behavior are the determinants to establish a service brand personality in the process of enhancing service interface. Hence, there should be a reinforced search for a method to efficiently manage the service staff who has a direct contact with customers in order to make an affirmative improvement of the customers' brand evaluation at the service interface. The findings suggest several managerial implications. 1) Results from the empirical study indicated that store environment factors have a strong positive impact on a service brand personality. To increase customers' repurchase intention of a service brand, the management is required to effectively manage store environment factors and create a friendly brand personality based on the corresponding service environment. 2) Mangers and researchers must understand and recognize that the store environment elements are important marketing tools, and that brand personality influences on consumers' repurchase intention. Based on such result of the study, a service brand could be utilized as an efficient measure to achieve a differentiation by enforcing the elements that are most influential among all other store environments for each service category. Therefore, brand personality established involving various store environments will further reinforce the relationship with customers through the elevated brand identification of which utilization to induce repurchase decision can be used as an entry barrier. 3) The study identified the store environment as a component of service brand personality for the store's effective communication with consumers. For this, all communication channels should be maintained with consistency and an integrated marketing communication should be executed to efficiently approach to a larger number of customers. Mangers and researchers must find strategies for aligning decisions about store environment elements with the retailers' marketing and store personality objectives. All ambient, design, and social factors need to be orchestrated so that consumers can take an appropriate store personality. In this study, the induced results from the previous studies were extended to the service industry so as to identify the customers' decision making process that leads to repurchase intention and a result similar to those of the previous studies. The findings suggested several theoretical and managerial implications. However, the situation that only one service brand served as the subject of analysis for each service category, and the situation that correlations among store environment elements were not identified, as well as the problem of representation in selection of samples should be considered and supplemented in the future when further studies are conducted. In addition, various antecedents and consequences of brand personality must be looked at in the aspect of the service environment for further research.

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Studies on the ecological variations of rice plant under the different seasonal cultures -I. Variations of the various agronomic characteristics of rice plant under the different seasonal cultures- (재배시기 이동에 의한 수도의 생태변이에 관한 연구 -I. 재배시기 이동에 의한 수도의 실용제형질의 변이-)

  • Hyun-Ok Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.3
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    • pp.1-40
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    • 1965
  • To measure variations in some of the important agronomic characteristics of rice varieties under shifting of seedling dates, this study has been carried out at the Paddy Crop Division of Crop Experiment Station(then Agricultural Experiment Station) in Suwon for the period of three years 1958 to 1960. The varieties used in this study were Kwansan, Suwon #82, Mojo, Paltal and Chokwang, which have the different agronomic characteristics such as earliness and plant type. Seeds of each variety were sown at 14 different dates in 10-day interval starting on March 2. The seedlings were grown on seed bed for 30, 40, 50, 60, 70 and 80 days, respectively. The results of this study are as follows: A. Heading dates. 1. As the seeding date was delayed, the heading dates was almost proportionally delayed. The degree of delay was higher in early varieties and lower in late varieties and the longer the seedling stage, the more delayed the heading date. 2. Number of days to heading was proportionally lessened as seeding was delayed in all the varieties but the magnitude varied depending upon variety. In other words, the required period for heading in case of late planting was much shortened in late variety compared with early one. Within a variety, the number of days to heading was less shortened as the seedling stage was prolonged. Early variety reached earlier than late variety to the marginal date for the maximum shortening of days to heading and the longer the seeding stage, the limitted date came earlier. There was a certain limit in seeding date for shortening of days to heading as seeding was delayed, and days to heading were rather prolonged due to cold weather when seeded later than that date. 3. In linear regression equation, Y=a+bx obtained from the seeding dates and the number of days to heading, the coefficient b(shortening rate of days to heading) was closely correlated with the average number of days to heading. That is, the period from seeding to heading was more shortened in late variety than early one as seeding was delayed. 4. To the extent that the seedling stage is not so long and there is a linear relationship between delay of seeding and shortening of days to heading, it might be possible to predict heading date of a rice variety to be sown any date by using the linear regression obtained from variation of heading dates under the various seeding dates of the same variety. 5. It was found out that there was a close correlation between the numbers of days to heading in ordinary culture and the other ones. When a rice variety was planted during the period from the late part of March to the middle of June and the seedling ages were within 30 to 50 days, it could be possible to estimate heading date of the variety under late or early culture with the related data of ordinary culture. B. Maturing date. 6. Within (he marginal date for maturation of rice variety, maturing date was proportionally delayed as heading was delayed. Of course, the degree of delay depended upon varieties and seedling ages. The average air temperature (Y) during the ripening period of rice variety was getting lower as the heading date. (X) was delayed. Though there was a difference among varieties, in general, a linear regression equation(y=25.53-0.182X) could be obtained as far as heading date were within August 1 to September 13. 7. Depending upon earliness of a rice variety, the average air temperature during the ripening period were greatly different. Early variety underwent under 28$^{\circ}C$ in maximum while late variety matured under as low as 22$^{\circ}C$. 8. There was a highly significant correlation between the average air temperature (X) during the ripening period, and number of day (Y) for the maturation. And the relationship could be expressed as y=82.30-1.55X. When the average air temperature during the period was within the range of 18$^{\circ}C$ to 28$^{\circ}C$, the ripening period was shortened by 1.55 days with increase of 1$^{\circ}C$. Considering varieties, Kwansan was the highest in shortening the maturing period by 2.24 days and Suwon #82 was the lowest showing 0.78 days. It is certain that ripening of rice variety is accelerated at Suwon as the average air temperature increases within the range of 18$^{\circ}C$ to 28$^{\circ}C$. 9. Between number of days to heading (X) related to seeding dates and the accumulated average air temperature (Y) during the ripening period, a positive correlation was obtained. However, there was a little difference in the accumulated average air temperature during the ripening period even seeding dates were shifted to a certain extent. C. Culm- and ear-lengths. 10. In general all the varieties didn't show much variation in their culm-lengths in case of relatively early seeding but they trended to decrease the lengths as seeding was delayed. The magnitude of decreasing varied from young seedlings to old ones. Young seedlings which were seeded during May 21 to June 10 didn't decrease their culm-lengths, while seedlings old as 80 days decreased the length though under ordinary culture. 11. Variation in ear-length of rice varieties show the same trend as the culm-length subjected to the different seeding dates. When rice seedlings aged from 30 to 40 days, the ear-length remained constant but rice plants older than 40 days obviously decreased their ear-lengths. D. Number of panicles per hill. 12. The number of panicles per hill decreased up to a certain dates as seeding was delayed and then again increased the panicles due to the development of numerous tillers at the upper internodes. The seeding date to reach to the least number of panicles of rice variety depended upon the seedling ages. Thirty- to 40-day seedlings which were seeded during May 31 to June 10 developed the lowest number of panicles and 70- to 80-day seedlings sown for the period from April 11 to April 21 reached already to the minimum number of panicles. E. Number of rachillae. 13. To a certain seeding date, the number of rachillae didn't show any variation due to delay of seeding but it decreased remarkably when seeded later than the marginal date. 14. Variation in number of rachillae depended upon seedling ages. For example, 30- to 40-day old seedlings which, were originally seeded after May 31 started to decrease the rachillae. On the other hand, 80-day old seedlings which, were seeded on May 1 showed a tendency to decrease rachillae and the rice plant sown on May 31 could develop narrowly 3 or 4 panicles. F. Defective grain and 1.000-grain weights. 15. Under delay of the seeding dates, weight of the defective grains gradually increased till a certain date and then suddenly increased. These relationships could be expressed with two different linear regressions. 16. If it was assumed that the marginal date for ripening was the cross point of these two lines, the date seemed. closely related with seedling ages. The date was June 10- in 30- to 40-day old seedlings but that of 70- to 80-day old seedlings was May 1. Accordingly, the marginal date for ripening was getting earlier as the seedling stage was prolonged. 17. The 1.000-grain weight in ordinary culture was the heaviest and it decreased in both early and late cultures. G. Straw and rough rice weights. 18. Regardless of earliness of variety, rice plants under early culture which were seeded before March 22 or April 1 did not show much variation in straw weight due to seedling ages but in ordinary culture it gradually decreased and the degree was became greater in late culture. 19. Relationship between seeding dates (X) and grain weight related to varieties and seedling ages, could be expressed as a parabola analogous to a line (Y=77.28-7.44X$_1$-1.00lX$_2$). That is, grain yield didn't vary in early culture but it started to decrease when seeded later than a certain date, as seeding was delayed. The variation was much greater in cases of late planting and prolongation of seedling age. 20. Generally speaking, the relationship between grain yield (Y) and number of days to heading (X) was described with linear regression. However, the early varieties were the highest yielders within the range of 60 to 110, days to heading but the late variety greatly decreased its yield since it grows normally only under late culture. The grain yield, on the whole, didn't increase as number of days to heading exceeded more than 140 days.

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