• Korean Journal of Materials Research
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• v.17 no.11
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• pp.580-586
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• 2007

To enhance the reliability of a newly designed reciprocating compressor applied in a domestic compressor, accelerated life tests were developed using new definitions of the sample size and the $B_1$ life index. In $1^{st}$ accelerated life testing, the compressor was locked due to the fracture of the suction reed valve. The failure modes and mechanisms of the suction reed valve in the accelerated tests were found to be similar to that of the failed product in the field. The root cause of the failure was the overlap between the suction reed valve and the valve plate in the suction port. The missing parameters in the design phase were modified by expanding the trespan size, introducing tumbling process, changing the material and thickness for the valve, introducing a ball peening and brushing process for the valve plate. In $2^{nd}$ accelerated life testing, the compressor was locked due to the interference between the crank shaft and thrust washer. The corrective plan was to heat treat the crank shaft. The $B_1$ life of the compressor improved from 1.5 to 12.9 years.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.321-326
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• 2003

The objectives of this study were to develop restructured meat products(RMPs) using a transgluta-minase(TGase) and to improve the textural characteristics of RMPs manufactured with pale, soft, exudative(PSE) pork hams. The pH values of RMPs with PSE and normal pork were 5.94 and 6.07, respectively, and their water activity value was approximately 0.981. The RMPs had 70∼72％ moisture, 4∼5％ fat, 19∼20％ protein, and approximately 3％ ash contents. No differences in pH, water activity, chemical composition, and hunter color values were observed between RMPs manufactured with normal and PSE pork(p＞0.05). However, RMPs containing PSE pork hams had higher drip loss(％)(p＞0.05) than those with normal pork hams after 10 days of refrigerated storage. Although no differences were observed in the texture profile analysis(TPA) hardness and sensory evaluation, RMPs with PSE pork hams tended to have more pores and lower binding capacity those with normal pork. This result indicated that additional substrates or longer tumbling time(＞4 hr) for the manufacture of RMPs containing PSE pork were required for the products to have similar palatability to those with normal pork.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.1 s.109
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• pp.17-24
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• 2005

The increase of using low grade ace, the unsorted mixed grade, as fibrous raw materials for the packaging paper results in the increment of fine screen reject owing to the strong tendency to reduce the slot width. Since the most of screen reject consists of undispersed fiber flake, the suitable treatment of the flake could increase the yield of ace recycling and decrease the amount of solid waste. In this work, the novel method combined the mild mechanical treatment by using Tumbling pulper with the biological treatment was developed and applied to the wet strength flake and the fine screen tail line reject originated from a packaging paper mill. The results showed the new method could provide much better efficiency for the disintegration of undispersed flake and for the recovery of fiber from the rejects. The application of the laboratory scaled-Pack pulper showed the possible separation technique for mill application by fractioning effectively the fiber from the treated solid waste.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.49 no.2
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• pp.74-80
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• 2000

In this paper, we present a control method of mobile power assist systems. Most of mobile power assist systems have a heavy base for preventing easy tumbling, so continual movement of the base during operations causes high energy consumption and gives the high risk of human injury. Furthermore, the slow dynamics of the base limits the frequency bandwidth of the whole system. Thus we propose a cooperation control method of the mobile base and manipulator, which removes the unnecessary movements of the base. In our scheme, the mobile base does not move until the center of gravity(C.G) of the system goes outside a safety region. When C.G. reaches the boundary of the safety region, the base starts moving to recover the manipulator's initial configuration. By varying the parameters of a human impedance controller, the operator is warned by a force feedback that C.G. is on the marginal safety region. Our scheme is implemented by assigning a nonlinear mass-damper-spring impedance to the tip of the manipulator. Our scheme is implemented by a nonlinear mass-spring impedance to the tip of the manipulator. The experimental results show the efficacy of the proposed control method.

• Food Science of Animal Resources
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• v.42 no.5
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• pp.723-743
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• 2022

Beef muscles from mature cows and bulls, especially those originating from the extremities of the carcass, are considered as underutilized due to unsatisfactory palatability. However, beef from culled animals comprises a substantial proportion of the total slaughter in the US and globally. Modern consumers typically favor cuts suitable for fast, dry-heat cookery, thereby creating challenges for the industry to market inherently tough muscles. In general, cull cow beef would be categorized as having a lower extent of postmortem proteolysis compared to youthful carcasses, coupled with a high amount of background toughness. The extent of cross-linking and resulting insolubility of intramuscular connective tissues typically serves as the limiting factor for tenderness development of mature beef. Thus, numerous post-harvest strategies have been developed to improve the quality and palatability attributes, often aimed at overcoming deficiencies in tenderness through enhancing the degradation of myofibrillar and stromal proteins or physically disrupting the tissue structure. The aim of this review is to highlight existing and recent innovations in the field that have been demonstrated as effective to enhance the tenderness and palatability traits of mature beef during the chilling and postmortem aging processes, as well as the use of physical interventions and enhancement.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.5 s.311
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• pp.19-27
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• 2006

Improvement in gait stability of fault-tolerant gaits for quadruped robots is addressed in this paper. The previously developed fault-tolerant gait gives a quadruped robot the ability to continue its walk against the occurrence of a leg failure. But it has a drawback of having marginal gait stability, which may lead to tumbling when the robot body's center of gravity is perturbed. To overcome such a drawback, a novel fault-tolerant gait is presented in this paper that generates positive stability margin against a locked joint failure, in which a joint of a leg is locked in a known place. Positive stability margin is obtained by adjusting foot positions of supporting legs between leg swing sequences. The advantages of the proposed fault-tolerant gait are discussed by comparing with the previous gait in terms of gait stability, stride length and gait velocity.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.5
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• pp.365-369
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• 2009

Overlapping windows are generally used for queries to process continuous data streams. Nevertheless, existing approaches discussed join algorithms only for basic types of windows such as tumbling windows and tuple-driven windows. In this paper, we propose an efficient join algorithm for overlapping windows, which are considered as a more general type of windows. The proposed algorithm is based on an incremental window join. It focuses on producing join results continuously when the memory overflow frequently occurs. It consists of (1) a method to use both of the incremental and full joins selectively, (2) a victim selection algorithm to minimize latency of join processing and (3) an idle time professing algorithm. We show through our experiments that the selective use of incremental and full joins provides better performance than using one of them only.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.101-107
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• 2015

The aim of this study was to investigate the effects of various marination processes on the quality characteristics of chicken breast prepared with chicken feet gelatin and wheat fiber. The chicken feet gelatin was swollen with hydrochloric solution (0.1 N HCl, pH $1.31{\pm}0.02$) and dehydrated by freeze-drying. The composition (w/w) of the marinade was water (10%), soy sauce (12%), phosphate (0.3%), wheat fiber (1.5%), and chicken feet gelatin (1.5%). Three samples of chicken breast were manufactured with Tumbler (only tumbler), Tenderizer (tenderizer and tumbler), and Injector (injector and tumbler). The water content of the Injector sample was significantly higher than those of the Tumbler and Tenderizer samples (p<0.05). During heating, the lightness of all chicken breasts increased and the redness decreased. The tumbling and cooking yield of the Injector sample were significantly higher than those of the Tumbler and Tenderizer samples (p<0.05). The shear force of the Tenderizer sample was significantly lower than that of the Tumbler and Injector samples (p<0.05). No significant differences, except for color, were observed in the sensory analysis of the samples. Thus, the proper selection of mechanical processing is important to improve the quality characteristics of marinated chicken breast, considering the types of final products.

• KSBB Journal
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• v.4 no.3
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• pp.221-228
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• 1989

Celluose is an insoluble substrate, therefore, a proper mixing of the cellulose suspension is essential for an effective enzymatic hydrolysis. To study the effect of mixing motion of various enzyme reactors on enzymatic hydrolysis of cellulose, three distinct types of biroreator: vertical impeller type bioreator(VITB), horizontal paddle type bioreactor(HPTB), and tumbling drum type bioreactor(TDTB), were assembled and their performance was compared. The optimal agitation speed was 100rpm for VITB and HPTB, 200rpm for TDTB. The saccharification efficiency of each reactor was compared under the optimal agitation intensity. The highest degree of saccharification was achieved in the case of VITB, especially, at high cellulose concentration. The VITB seems to be the most suitable type of bioreactor that can maintain proper mixing pattern for effective enzyme reaction. In the view of energy consumption, the TDTB showed the lowest value: however, the energy consumption was rapidly increased at high concentration of celluose. To dertermine the most suitable type of bioreactor, the entire process, including substrate cost, substrate concentration, and feasibility of scale-up, needs to be evaluated.

• Archives of Plastic Surgery
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• v.36 no.1
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• pp.118-121
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• 2009

Purpose: Constricted ear, which is named by Tanzer includes lop ear, cup ear, and sort of prominent ear. It has classified three groups by Tanzer, especially grou I and IIA have been corrected by banner flap, Musgrave's technique, tumbling concha - cartilage flap, reversed banner flap and others. However, these techniques were too invasive for correcting mild degree of deformity. Therefore, we corrected the ear with mattress suture which is simple and less invasive. Method: The operations were done against 5 patients from 2005 March to 2008 April. All the cases were unilateral ears with constriction included helix and scaphoid fossa without difference in length between both ears. Though a posterior auricular skin incision, the folded cartilage is exposed and two parallel incisions on superior crus were made. After mattress suturing in cartilage, the superior crus of antihelix was formed and its force enables the folded portion to be in a normal anatomic position. Result: All of 5 patients got satisfactory results. There were no complications like hematoma or skin necrosis, and no recurrence during follow - up period(the average period was 9 months). And we couldn't recognize the difference between height of both auricles. Conclusion: Mattress suture is simple, less invasive, and suitable on correcting mild deformity of constricted ear with better result, so here we suggest the method.