• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.120-123
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• 2004

The lap splice lengths of deformed steel reinforcing bars and GFRP bars were experimentally compared using beam specimens. The purpose was to evaluate the length required of the GFRP bar to develop strength at least equivalent to the conventional steel reinforcing bar. The main test variable was the lap splice length: 10, 20, 30 $d_b$ for the deformed steel bars and 20, 30, 40 $d_b$ for the GFRP bars. Two different types of GFRP bars were tested: (1) one with spiral-type deformation and (2) plain round bars. Elastic modulus was about 1/5 of the steel bars while the tensile strength was about 690 MPa for the GFRP bars. Nominal diameter of the GFRP bars and steel bars was 12.7 and 13 mm, respectively. Normal strength concrete (28-day $f_{cu}$ = 30 MPa) was used. For the conventional steel bars (SD400 grade), strength over 400 MPa in tension was developed using the lap splice length of 20 and 30 $f_{cu}$. Only $87\%$ of the nominal yield strength was reached with the lap splice length of 10 $d_b$. For the spiral-type deformed GFRP bars with $40-d_b$ lap splice length, 440 MPa in tension was determined. The maximum tensile strength developed of the GFRP bars with smaller lap splice lengths decreased. The plain GFRP bar was not effective in developing the tensile strength even with $40-d_b$ lap splice length. Development of the cracks on beam surface was clearly visible for the beams reinforced with the GFRP bars. Mid-span deflections, however, were significantly smaller than the comparable beams with conventional steel bars indicating potential ductility problem.

• The KIPS Transactions:PartC
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• v.14C no.2
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• pp.185-190
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• 2007

The efficient node energy utilization is one of important performance factors in wireless sensor networks because sensor nodes operate with limited battery power. To extend the lifetime of the wireless sensor networks, maintaining balanced power consumption between sensor nodes is more important than reducing each energy consumption of the sensor node in the network. In this paper, we proposed a cluster formation algorithm to extend the lifetime of the networks and to maintain a balanced energy consumption of nodes. To obtain it, we add a tiny slot in a round frame, which enables to exchange the residual energy messages between the base station (BS). cluster heads, and nodes. The performance of the proposed protocol has been examined and evaluated with the NS 2 simulator. As a result of simulation, we have confirmed that our proposed algorithm show the better performance in terms of lifetime than LEACH. Consequently, our proposed protocol can effectively extend the network lifetime without other critical overhead and performance degradation.

• Journal of the Korean Society of Costume
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• v.60 no.8
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• pp.67-85
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• 2010

School uniform has improved greatly in terms of fit, size, function, and design due to steep competition in the market and the strong interest of researcher, while little effort has been made for physical training uniform, so the objective of this study is to provide basic research data of the training uniform for the improvement of its design and fitness. For this purpose, 327 high school girls provided information on size and design of their uniform, level of satisfaction, the recognized ease in uniform. Most students wore the physical training uniform in another classes and the long sleeved shirt were the most popular one. They often used the uniform for the protection from cold and for comfortable activeness. For a long sleeved shirt, most students preferred raglan sleeve, zip-up collar, straight waist line, and ribbed sleeve cuffs and hem. For long pants, students preferred elastic waist band and ribbed pants cuffs. Currently, the short-sleeved shirt mostly had a shirts collar, ribbed hem, straight waist line with raglan sleeve, but students wanted a round neck and set-in sleeve. For overall level of satisfaction, students showed high satisfaction in terms of function and psychological effect, while aesthetic quality of the uniform was needed to be much improved. Most students evaluated that the circumference of uniforms properly fit or had a little ease, and students considered waist size the most suitable. The long pants length evaluated properly fit or a little long. Students accepted that the ease of summer uniform was more suitable than winter uniform's both at circumference and at length. Depending on students' height distribution, the length of long pants and short pants varied significantly.

• The Korean Journal of Cytopathology
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• v.7 no.1
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• pp.69-74
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• 1996

Malignant rhabdold tumor is a distinct renal tumor in the pediatric age group. It was originally described as a rhabdomyosarcomatold variant of Wilms' tumor. However, subsequent studies fatted to confirm myogenous differentiation, so it is now considered to be a distinct and unique type of highly malignant tumor, histogenetically unrelated. Although extrarenal forms of this tumor are rare, several examples have been described in other sites, especially the liver, prostate, paravertebral area, urinary bladder and soft tissue. We experienced a case of malignant rhabdiod tumor located in the intraabdominal cavity in a 10 month-old boy. Smear of peritoneal fluid showed round, polygonal and irregular shaped cells with large nuclei, ample cytoplasm containing light pink to purple cytoplasmic inclusions, and one or a few prominent nucleoli. Immunocytochemistry revealed positivity to cytokeratin, epithelial membrane antigen and vimentin, and negativity to desmin and neuron-specific enolase. These distinct cytologic appearance and immunophenotypes were most consistent with a diagnosis of extrarenal malignant rhabdoid tumor. The cytoplasmic inclusions were correlated with eosinophilic inclusions seen in histologic section and electron microscopy confirmed this interpretation, showing filamentous aggregations in the cytoplasms of the tumor cells.

• Journal of Satellite, Information and Communications
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• v.10 no.4
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• pp.101-106
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• 2015

In this paper, a shared band transmission, in which downlink signals from satellite to both earth station and user terminal are transmitted in the same frequency band, is considered. For proper operation of such shared band transmission, self-interference caused by the transmitted signal from its own transmitter should be cancelled and the desired signal from the other transmitter should be obtained. The self-interference is sent by its own transmitter and it can be easily regenerated with the estimated round-trip delay. In addition to this delay, non-linearity effects caused by power amplifiers at the earth station and satellite should be exploited. The proposed interference canceller divided into two parts: one is subtraction of the transmitted signal with delay and non-linearity effects, and the other is adoptive filter to suppressed the residual interference. Through computer simulations, the effectiveness of the proposed system is verified.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.7
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• pp.2512-2529
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• 2015

Wireless mesh networks (WMNs) provide an efficient and flexible method to the field of wireless networking, but also bring many security issues. A mesh point may lose all of its available links during its movement. Thus, the mesh point needs to handover to a new mesh point in order to obtain access to the network again. For multi-domain WMNs, we proposed a new ID-based signcryption scheme and accordingly present a novel ID-based handover protocol for mesh points. The mutual authentication and key establishment of two mesh points which belong to different trust domains can be achieved by using a single one-round message exchange during the authentication phase. The authentication server is not involved in our handover authentication protocol so that mutual authentication can be completed directly by the mesh points. Meanwhile, the data transmitted between the two mesh points can be carried by the authentication messages. Moreover, there are no restrictions on the PKG system parameters in our proposed multi-domain ID-based signcryption scheme so our handover scheme can be easily applied to real WMNs circumstances. Security of the signcryption scheme is proved in the random oracle model. It shows that our protocol satisfies the basic security requirements and is resistant to existing attacks based on the security of the signcryption. The analysis of the performance demonstrates that the protocol is efficient and suitable for the multi-domain WMNs environment.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.701-705
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• 2007

Seven rc mutant and seven normal male birds (Rhode Island Red suie, RIR) were used in this study to determine the effects of rc mutation on semen characteristics, testosterone profile and spermatogenic tissues. All birds were randomly selected at week 12 of age and housed in individual cages and were fed and watered ad libitum. The birds were exposed to a 14L:10D light cycle during experiment. Semen were collected at weeks 22 to 23 from each bird twice a week and evaluated for semen volume (SV), sperm concentration (SC), total sperm count (TSC), percent of sperm motility (%SM), dead sperm (%DS), and sperm metabolic activity (SMA). To determine the testosterone concentration (TC) in plasma, blood was collected at weeks 12, 16 and 18. Testicular tissue were collected, processed and evaluated for semineferous tubule diameter (STD), round spermatid number (RSN), percent elongated sperm (%ES) and semineferous tubules length (STL). Body weight (BW), comb weight (CW) and testes weight (TW) were weighted at the end of experiment (week 23). The SV, TSC and %SM were significantly higher in normal birds but the %DS was higher in blind birds (p<0.05). The SC did not differ significantly between the two groups but its value was higher in normal birds. The sperm metabolic activity in the first h of collection did not differ significantly between the two groups but after 24 h, the level of SMA in normal group was significantly higher (p<0.05). The level of TC did not differ significantly between the two genotype groups but normal birds had higher TC in all collections except the last one. The STD, RSN, %ES and STL in normal birds were higher when compared to blind birds but the differences were insignificant except for ES percent. The BW, CW and TW between the two groups did not differ significantly but the weights were higher in normal group compared to blind birds. Statistical analysis of semen characteristics, testosterone profile and histological factors were indicated detrimental effects of rc mutation in prepubertal RIR blind male birds due to lack of light.

• Journal of Korea Multimedia Society
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• v.6 no.3
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• pp.419-428
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• 2003

Several methods have been studied to prune the parasitic branches that cause unfortunately from thinning a shape to get its skeleton. We found that the symmetric path finding method was most efficient because it followed the boundary pixels of the shape just once. In this paper, its extended method is proposed to apply to removing the noise branches that protrude out of the boundary of a segmented or extracted shape in a given image. The proposed method can remove a noise branch with one-pixel width and also remove the noise branch that includes a round shape called a noise blob. The method uses a 4-8-directional boundary-following technique to determine symmetric paths and finds noise branches with noise blobs by detecting quasi-symmetric paths. Its time complexity is a linear function of the number of boundary pixels. Interactively selectable parameters are used to define various types of noise branches flexibly, which are the branch - size parameter and the blob-size parameter. Experimental results for a practical shape and various artificial shapes showed that the proposed method was very useful for simplifying the shapes.

• Korean Journal of Veterinary Research
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• v.8 no.2
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• pp.98-109
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• 1968

The small type piroplasma which is known to be prevailing in Korean cattle was injected to un-susceptible hosts such as mice, guinea pigs, rats, rabbits, fowls and developing chicken eggs by i.v., i.p, and intra C.A.M. routes, and its morphological development in each animal species was observed. 1. The small type piroplasma of cattle did not produce any pathogenicity in the experimental animals such as mice, guinea pigs, rats, rabbits, fowls and developing chicken embryos. However, only a partial sign for developing cycle of the organism was observed in the peritoneal fluid. The schizogony of protozoa was not detected in any organs of the inoculated animals. 2. In the animals inoculated, the parasites of I-III types, relative to the process of time in the host, have changed their shapes into IV-VI types and then VI-X types however, the type X was not restored to the type I. In guinea pigs, more grape type was detected then X type in number, and in process of time, the shape was changed from round to elliptic, and the pointed end of the organism appeared in flesh color. 3. None of the organisms were found from the blood stream of inoculated animals excepts only a few piroplasma as were found in the experimental mice shortly after inoculation or i.v. route, No protozoa was also found in the organs of the animals autopsied. 4. The form change of protozoa was more clear in these animals than that in susceptible host. The most piroplasmas have changed their forms into VI-X types 30 hours after inoculation and were dispersed from R.B.C. Tracing of piroplasrna beyond this stage was not attempted. 5. The small type piroplasma comprises in I. X types and it is further believed that VII-X types which were freed from one cell proceeded to invade others. The from of development resembles to the small type of piroplasma which is prevailing in Japan.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.385-392
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• 2014

Workshift is a method of organization of working time in which workers succeed one another at the workplace. The shift work system enables round-the-clock activities required for meeting technological needs and productive and economic demands. This study tries to find the practical implications by investigating the workshift systems which are successfully applied in two representative Korean companies, Yuhan-Kimberly and POSCO. Case study method is applied in oder to analyze the special feature of shift work systems in two companies. It is concluded that the shift system(2-4system) has positively enhanced firm's capability including workers' satisfaction and commitment, product quality, and productivity. Specifically, the shiftwork system applied in the companies has significantly influenced on the workers' work-life balance.