• The Journal of the Convergence on Culture Technology
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• v.8 no.5
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• pp.591-596
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• 2022

Since 4-bar linkage widely used in various industrial fields has a fixed link length, it is inconvenient to add an independent link structure or control device to change the movement of output link. Therefore, this paper proposes a new concept of variable 4-bar linkage mechanism to selectively adjust the movement of the output link to fit desired situations, and applied to the commercial table fans, which is a representative product using a 4-bar linkage system. The optimal rotation angle steps for efficiency are determined experimentally and the appropriate lengths of linkage to fit each step are calculated analytically. Changes in the linkage length are implemented by the rotational motion using a grooved cylindrical cam and the feasibility of the proposed variable linkage mechanism is verified through fabrication and measurement. The presented variable link mechanism is expected to improve the efficiency of industrial robots and fuel valve systems.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.6 no.2
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• pp.9-14
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• 2012

In this study, an advanced knee joint for active prosthesis leg driven by a linear actuator is suggested. The structure of knee joints of existing active prosthesis legs consists of three links. This kind of linkage requires large torque to drive the active prosthesis legs. Thus a new linkage structure is suggested to solve such problem in this paper. Motion characteristics of the suggested linkage are examined in the simulation. The motion simulation results show that the proposed linkage is able to imitate human gait cycles with the half of linear actuator speed in existing linkages.

• Journal of the Economic Geographical Society of Korea
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• v.13 no.2
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• pp.181-195
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• 2010

The policy of industrial complexes (innovative clusters) is being changed to build the linkage structure within Mega Economic Region according to the national policy of Mega Economic Region. The aim of this analysis is to draw the hypothetical linkage structure of industrial complexes in the internal and external Capital Region. First, with the survey data of firms located in the industrial complexes, we can catch the regional linkages of firms in the local area and internal and external Mega Economic Region. Next, the measure of structural similarity between industrial complexes is calculated with the number of employees by industrial sectors. After considering the geographical distance between industrial complexes, the percentage of industrial sectors and the location quotient synthetically, the idea of hub-and-spoke type linkage structure between clusters is deduced.

• Journal of the Korean Society for information Management
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• v.39 no.4
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• pp.99-125
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• 2022

In order to understand a record, not only the contents of the record but also the production background and work context of the record must be grasped. It also requires a function that makes it easy to find related records scattered across various departments and agencies. Accordingly, the 'linkage' of information in archival information services is becoming more important. NAK also emphasizes 'linkage' as a search service function of the archives management system, but some problems were identified at the National Archives Portal Service (NAPS) such as a lack of linkage with authority data, disruption of internal service, and absence of linkage with other related organizations. To solve the limitations of the NAPS, we selected and analyzed advanced record management institutions that have built an ideal linkage service; checked the overall linkage structure of these institutions; and identified characteristics that could not be seen by other institutions. Also, elements that can be adopted from the NAPS were derived. Next, the current status of the NAPS linkage structure was analyzed to identify the parts that were not linked and the items that need to be improved in the linkage method, and specific advancement plans were suggested to solve these problems. The purpose of this study is to increase users' satisfaction with search and to advance the accessibility and utilization of records and internal services through improved linkage services of NAPS.

• Journal of Electrical Engineering and Technology
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• v.5 no.4
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• pp.592-596
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• 2010

In a multi-layer interior permanent magnet synchronous motor, the d- and q-axis parameters vary nonlinearly according to different load conditions, consequently changing the level of saturation. The flux-linkage of d- and q-axis conveys ripple characteristics resulting from mechanical structure and degree of magnetic saturation. If the calculated flux-linkage is correct, the torque using the Maxwell stress tensor method is the same torque calculated by the flux-linkage. However, discrepancy between results exists. In this paper, the d- and q-axis flux-linkage, in consideration of the ripple characteristic, is calculated. Simulation results are then compared with experimental results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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• pp.74-79
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• 2021

Generally, multi-legged walking robots have excellent mobility in rough and uneven terrain, and they are deployed for the safety of rescuers in various disaster environments. However, as each leg is driven by a number of actuators, it leads to a complicated structure and high power consumption; therefore, it is difficult to put them into practical use. In this article, a new concept is proposed of a walking robot whose legs are driven by a complex linkage structure to overcome the deficiencies of conventional multi-legged walking robots. A double crank-rocker mechanism is proposed, making it possible for one DC motor to actuate the left and right movements of two neighboring thighs of the multi-legged walking robot. Each leg can also move up and down through an improved cam structure. Finally, each mechanism is connected by spur and bevel gears, so that only two DC motors can drive all legs of the walking robot. The feasibility of the designed complex linkage mechanism was verified using the UG NX program. It was confirmed through actual production that the proposed multi-legged walking robot performs the desired motion.

• Food Science and Biotechnology
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• v.18 no.1
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• pp.271-274
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• 2009

Cereal $\beta$-glucans, linked essentially by mixed $\beta$-(1,4/1,3) glycosidic bonds, were extracted, purified, and structurally identified. Previously chemical structure of barley $\beta$-glucans was characterized from 3 varieties of 'Gang', 'Ohl', and 'Gwangan', and the (1,4)/(1,3) linkage ratio of the $\beta$-glucans was identical. In this study, $\beta$-glucans from 1 barley ('Chal') and 3 oat ('Ohl', 'Samhan', and 'Donghan') varieties were structurally scrutinized, and the linkage pattern of total 7 cereal $\beta$-glucans was compared. The amount of 2 major 3-O-$\beta$-cellobiosyl-D-glucose (DP3) and 3-O-$\beta$-cellotriosyl-D-glucose (DP4) from barley and oat accounted for only 66.6-73.3 and 68.12-81.89% of water-extractable $\beta$-glucan fractions, and the (1,4)/(1,3) linkage ratios of both barley and oat $\beta$-glucans were within very narrow range of 2.27-2.31 and 2.38-2.39, respectively, among the cultivars tested. Structural difference in the cereal $\beta$-glucans was evident when DP3:DP4 ratio in the $\beta$-glucan structure was compared. As a result, this ratio was significantly greater for barley $\beta$-glucan (2.26-2.74) than for oat (1.54-1.66). Chal-B had the greatest DP3 to DP4 ratio among the samples, which in turn reflected the least amount of (1,4)-linkages.

• Journal of Technology Innovation
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• v.6 no.1
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• pp.128-162
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• 1998

A continuous development of new products is the lifeblood for firms that hope to maintain competency in competitive environments. Ongoing success in these environments is dependent on whether the management can choose or can't chose the proper mix of new product development strategy, new product development process, and organizational structure. Rather than considering the interrelationship among these success factors, however, most previous studies of new products development have examined these issues individually. Moreover, because past research has been unidimensional in nature, there is a lack of knowledge about how new product development strategy, process, and structure could be linked up each other. Consequently, we have no complete perspective of the linkage among new product development strategy, process, structure, and performance. The purpose of this study is to examine the new product development strategy, process, and structure of firms, and explore the effect of each on performance as well as linkage among strategy, process, strategy and structure.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.12
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• pp.1672-1679
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• 2013

Linkage disequilibrium between markers or genetic variants underlying interesting traits affects many genomic methodologies. In many genomic methodologies, the effective population size ($N_e$) is important to assess the genetic diversity of animal populations. In this study, dairy cattle were genotyped using the Illumina BoviveHD Genotyping BeadChips for over 777,000 SNPs located across all autosomes, mitochondria and sex chromosomes, and 70,000 autosomal SNPs were selected randomly for the final analysis. We characterized more accurate linkage disequilibrium in a sample of 96 dairy cattle producing milk in Korea. Estimated linkage disequilibrium was relatively high between closely linked markers (>0.6 at 10 kb) and decreased with increasing distance. Using formulae that related the expected linkage disequilibrium to $N_e$, and assuming a constant actual population size, $N_e$ was estimated to be approximately 122 in this population. Historical $N_e$, calculated assuming linear population growth, was suggestive of a rapid increase $N_e$ over the past 10 generations, and increased slowly thereafter. Additionally, we corrected the genomic relationship structure per chromosome in calculating $r^2$ and estimated $N_e$. The observed $N_e$ based on $r^2$ corrected by genomics relationship structure can be rationalized using current knowledge of the history of the dairy cattle breeds producing milk in Korea.

• Journal of the Korean Society for information Management
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• v.21 no.1
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• pp.93-117
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• 2004

This study is to develop a hierarchic clustering model fur document classification and browsing in OPAC systems. Two automatic indexing techniques (with and without controlled terms), two term weighting methods (based on term frequency and binary weight), five similarity coefficients (Dice, Jaccard, Pearson, Cosine, and Squared Euclidean). and three hierarchic clustering algorithms (Between Average Linkage, Within Average Linkage, and Complete Linkage method) were tested on the document collection of 175 books and theses on library and information science. The best document clusters resulted from the Between Average Linkage or Complete Linkage method with Jaccard or Dice coefficient on the automatic indexing with controlled terms in binary vector. The clusters from Between Average Linkage with Jaccard has more likely decimal classification structure.