• Journal of the Korea Concrete Institute
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• v.23 no.3
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• pp.393-400
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• 2011

The needs for high strength structural materials have recently increased, because construction and cost efficiencies are demanded by the costumers. But, the use of high strength reinforcing bars requires longer development and splice lengths compared to normal strength bars. This restriction may cause reduction in construction efficiency and require more complicated details. The purpose of this paper is to evaluate the bond strength on the rib shape of reinforcing bars to decrease development and splice lengths of high strength reinforcements. Total of 5 simple beam specimens were tested, and the main test variable was a rib shape of reinforcing bars. Test data was analyzed in the viewpoint of bond strength, load-deflection relationship, and crack pattern. Test results indicated that the bond strength of high relative rib area reinforcing bars increased up to 11% compared to normal strength reinforcements. And the improved rib shape reinforcements, which were formed with high and low height rib, increased the bond strength up to 23% even though the relative rib area was same as the high relative rib area reinforcements. Serviceability performances such as deflection number of cracking, and maximum crack width were similar in all specimens, so it is safe to conclude that the improved rib shape reinforcements can be applied to the structural members.

• Korean Journal of Construction Engineering and Management
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• v.7 no.5
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• pp.105-114
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• 2006

The construction craft workers have been getting older and have become drained, in spite of the vital factor that it directly affects productivity and quality as a final producer. This situation in the construction industry is ultimately due to evasion of performances by young craft workers. Therefore, the aim of this study is to propose the certification and level system of construction craft workers and to extract young craft workers from the market for construction craft workers so as to supply and demand high quality of craft workers. First of all, the present status and problems of the domestic construction craft workers are considered in this study. Furthermore, the appropriate way to establish its certification and level system is suggested from the Interview with experts, as well as references of German and Australian case. The revitalization of certification and level system provided in this study is expected to ensure that the craft workers are not simple laborers, but are required the professional knowledge and skill. Besides, it will lead to strengthen specificity and to break from aging, by taking young and qualified craft workers into the construction industry. Also, it will promote an employment stability by connecting the social security system.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.5
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• pp.401-414
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• 2018

Planing hull type ships are often equipped with interceptor or trim tab to improve the excessive trim angle which leads to poor resistance and sea keeping performances. The purpose of this study is to design a controller to control the attitude of the ship by controllable stern interceptor and validate the effectiveness of the attitude control by the towing tank test. Embedded controller, servo motor and controllable stern interceptor system were equipped with planing hull type model ship. Prior to designing the control algorithm, a model test was performed to identify the system dynamic model of the planing hull type ship including the stern interceptor. The matrix components of model were optimized by Genetic Algorithm. Using the identified model, PID controller which is a classical controller and sliding mode controller which is a nonlinear robust controller were designed. Gain tuning of the controllers and running simulation was conducted before the towing tank test. Inserting the designed control algorithm into the embedded controller of the model ship, the effectiveness of the active control of the stern interceptor was validated by towing tank test. In still water test with small disturbance, the sliding mode controller showed better performance of canceling the disturbance and the steady-state control performance than the PID controller.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.609-618
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• 2017

This paper presents the quantitative evaluation method for technologies acquired from the defense offset program. We firstly deduced the consideration in development by gathering the opinions of 128 experts by conducting a survey. Next, we made up an additional 49 experts for developing a performance management system of the offset program. The management system covered 4 technology fields which are defense R&D, depot maintenance, performance improvement, and manufacturing. The development procedure was composed of 4 parts: setting-up of work process, defining performance indicators, calculating weighted values of each indicator, and devising quantitative method. The results of this research could be used for enhancing the effectiveness of the offset program in 3 ways: establishing a systematic work process after acquisition of technology in offset program, establishing the positive feedback architecture by providing incentives to superior institute or company which is appointed through quantitative performance evaluating, and publicizing and promoting quantified outstanding performances for contributing to advance the offset program.

• Journal of the Korean Society for Library and Information Science
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• v.16
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• pp.207-242
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• 1989

This study hypothesizes that the present deadlock situation in public library development in Korea has chiefly been caused by the underdevelopment of the consciousness of the librarians themselves presently employed in various levels of public libraries throughout the country. This study, therefore, aims to define the areas in librarians' consciousness in which elements of backwardness prevail, and thereby to produce a theoretical framework to develop public library services in Korea on an indigenous footing. To do this, the present author set up a relationship between the traditional consciousness of the Korean People and the public library performances, based on existing published materials. In order to prove hisirelatonship, he then sent out questionnaires to public librarians and male high school students and analyzed the answered questionnaires using Pearson's Correlation Analysis and Multiple Regression Analysis. Results of the analysis are asfollows: 1) Those who place an importance on the show of respectability tend to prefer to work in an indirect services area. 2) Male librarians tend to show a job satisfaction because of chances of promotion reflecting a positive correlation between this-worldiness of librarians and their job satisfaction. 3) Male librarians tend to be satisfied in their job for the conviction for their self-accomplishment, and female librarians tend to be satisfied in their job for the attention and respect they receive from users. 4) Library technicians tend to draw their job satisfaction from their sense of job stability. 5) Male librarians tend to be dissatisfied for the lack of the monetary rewards they receive, while female librarians tend to be dissatisfied for the lack of promotional chances. 6) Most librarians tend to maintain a positive job attitude for the promotional chances, reflecting a positive correlation between this­worldliness in librarians and their service attitude. 7) Power-orientednes in librarians and their job satisfaction correlate negatively in the case of male librarians. This does not apply to female librarians. 8) Power-orientedness and good service attitude correlate negatively in the case of male librarians. This does not apply to female librarians. 9) The fact that male high school students desire to enter good colleges and universities and to obtain a position in his job positively correlate to the fact that public libraries have transformed themselves into a mere reading room. 10) Male library science students show a maladjustment in their major department in earlier years for the professional uncertainty, and as they advance into senior years they show a positive attitude about the library profession.

• Journal of Korean Theatre Studies Association
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• no.52
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• pp.5-59
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• 2014

This paper investigates the development and aesthetics of Korean political theatre from its quickening period 1920s to democratization era 1990s. Political theatre before 90s developed an antithesis resistant movement toward Korean modern history that had been scattered with suppressing political circumstances such as colonial era and dictatorial government, the movement has powerful activity and social influences. Just like the 20 century political theatre had been quickened under the influence of Marxism at Russia and Germany in 1920s, Korea's political theatre began in socialism theatre movement form around the same time. Proletarian theatre groups had been founded in Japan and Korea, and developed into practical movement with organized connection. However, the political theatre movement in Japanese colonial era was an empty vessel makes great sound but not much accomplishments. Most performance had been canceled or disapproved by suppression or censorship of the Japanese Empire. The political theatre in liberation era was the left drama inherited from Proletarian theatre of the colonial era. Korean Theatre alliance took lead the theatrical world unfold activities based on theatre popularization theory such as 'culture activists' taking a jump up the line and 'independent theatre' peeping into production spot as well as the important event, Independence Movement Day Memorial tournament theatre. Since 1947, US army military government in Korea strongly oppressed the left performances to stop and theatrical movement was ended due to many left theatrical people defection to North Korea. The political theatre in 1960s to 70s the Park regime, developed in dramatically different ways according to orthodox group and group out of power. The political theatre of institutional system handled judgment on sterile people and had indirect political theatre from that took history material and allegory technique because of censorship. In political theatre out of institution, it started outdoor theatre that has modernized traditional performance style and established deep relationship with labor spot and culture movement organizations. Madangguek(Outdoor theatre) is 'Attentive political theatre', satirizing and offending the political and social inconsistencies such as the dictatorial government's oppression and unbalanced distribution, alienation of general people, and foreign powers' pillage sharply as well as laughing at the Establishment with negative characters. The political theatre in 1980s is divided into two categories; political theatre of institutional system and Madangguek. Institutional Political theatre mainly performed in Korea Theatre Festival and the theatre group 'Yeonwoo-Moudae' led political theatre as private theatre company. Madangguek developed into an outdoor theatrical for indoor theatre capturing postcolonial historical view. Yeonwoo-Moudae theatre company produced representative political plays at 80s such as The chronicles of Han's, Birds fly away too, and so on by combining freewheeling play spirit of Madangguek and epic theatre. Political theatre was all the rage since the age of democratization started in 1987 and political materials has been freed from ban. However, political theatre was slowly declined as real socialism was crumbling and postmodernism is becoming the spirit of the times. After 90s, there are no more plays of ideology and propaganda that aim at politicization of theatre. As the age rapidly entered into the age of deideology, political theatre discourse also changed greatly. The concept 'the political' became influential as a new political possibility that stands up to neoliberalism system in the evasion of politics. Rather than reenact political issues, it experiments new political theatre that involves something political by deconstructing and reassigning audience's political sense with provocative forms, staging others and drawing discussion about it.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.4
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• pp.51-62
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• 2019

This paper investigates the effects of prior entrepreneurial experience on new venture performance. Entrepreneurial experience has significant impacts on the early development processes of new ventures founded by experienced entrepreneurs. There are inconclusive results on the relationships between entrepreneurial experience and new venture performance. Based on the data of Korean new ventures, this paper empirically analyze these relationships of different entrepreneurial experience on new venture performance. Success experience has positive effects on employment but no effect on financial performance. Failure experience has negative relationships with financial performance as well as employment. There are moderating effect of firm age on the relationship of only failure experience with performance. Finally this paper suggests theoretical and practical implications of entrepreneurial experience on new ventures' development and performances.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.6
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• pp.143-154
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• 2018

This study is intended to look into the effects of SCM(supply chain management) competency and process improvement on operational performance in small and venture companies. To achieve this, a survey was empirically carried out to 179 small and venture manufacturing companies. The findings showed that the SCM competency had a significant effect on the process improvement and operational performance in small and venture companies, adopting all hypotheses. And the process improvement had a significant mediating effect on the relationship between SCM competency and operational performance in small and venture companies, adopting hypothesis 4. As for the findings, strategic alliance, technology development, competency concentration as SCM competencies and starting preparation, detailed planning, implementation management as process improvements were factors that have positive effects on quality performance, cost reduction and profit increase as operational performances in small and venture companies. In other words, the better process and performance by the maximized SCM competencies require selective input strategies for strategic alliance, technology development and competency concentration in small and venture companies. And for its early application and settlement, the starting preparation and detailed planning of business process within small and venture companies need to be jointly put in action under clear company-wide goal management. Consequently, the expected performance can be maximized when strict management and implementation lead to these attributes.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1323-1337
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• 2020

GEO-KOMPSAT-2A AMI (Advanced Meteorological Imager) radiometric calibration evaluation is an essential element not only for functional and performance verification of the payload but for the quality of the sensor data. AMI instrument consists of six reflective channels and ten thermal infrared ones. One of the key parameters representing radiometric properties of the sensor is a SNR (Signal-to-Noise Ratio) for the reflective channels and a NEdT (Noise Equivalent delta Temperature) for the IR ones respectively. Other important radiometric calibration parameters are a dynamic range and a gain value related with the responsivity of detectors. To verify major radiometric calibration performance of AMI, an offline radiometric evaluation tool was developed separately with a real-time AMI data processing system. Using the evaluation tool, validation activities were carried out during the GEO-KOMPSAT-2A In-Orbit Test period. The results from the evaluation tool were cross checked with those of the HARRIS, which is the AMI payload vendor. AMI radiometric evaluation activities were conducted through three phases for both sides (Side 1 and Side 2) of AMI payload. Results showed that performances of the key radiometric properties were outstanding with respect to the radiometric requirements of the payload. The effectiveness of the evaluation tool was verified as well.

• Membrane Journal
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• v.32 no.6
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• pp.427-441
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• 2022

Polymer electrolyte membrane (PEM) serving as a separator that can prevent the permeation of unreacted fuels as well as an electrolyte that selectively transports protons from the anode to the cathode has been considered a key component of polymer electrolyte membrane fuel cell (PEMFC). The perfluorinated sulfonic acid-based PEMs, represented by Nafion®, have been commercialized in PEMFC systems due to their high proton conductivity and chemical stability. Nevertheless, these PEMs have several inherent drawbacks including high manufacturing costs by the complex synthetic processes and environmental problems caused by producing the toxic gases. Although numerous studies are underway to address these drawbacks including the development of sulfonated hydrocarbon polymer-based PEMs (SHP-PEMs), which can easily control the polymer structures, further improvement of PEM performances and durability is necessary for practical PEMFC applications. Therefore, this study focused on the various strategies for the development of SHP-PEMs with outstanding performance and durability by 1) introducing cross-linked structures, 2) incorporating organic/inorganic composites, and 3) fabricating reinforced-composite membranes using porous substrates.