• Journal of The Korean Society of Grassland and Forage Science
• /
• v.3 no.2
• /
• pp.67-76
• /
• 1983

This experiment was carried out to investigate the effects of the different nitrogen rates and cutting heights on the dead stubble after cutting, and the carbohydrate reserved in stubble of sorghum-sudangrass hybrid (Sorghum bicolor (L.) Moench) Pioneer 988. The experiment was undertaken in the Experimental Livestock Farm of Agriculture Coll., Seoul Nat'l Univ. In Suweon, 1981 and 1982. The results obtained are summarized as follows: 1. The dead stubble after cutting was found to be great with high rate of nitrogen fertilizer and low cutting height. It was also learned that the rainfall during forage cutting period made the dead stubble increased. 2. A significant higher (p<0.05) carbohydrate reserves in the stubble was observed in the high stubble height at the first cutting time and 6th through 7th day after the first cutting. The results indicate that the high stubble height reserves more carbohydrate for the early regrwoth stage after the first cutting when comparing with the low stubble. 3. The content of carbohydrate reserves was influenced by climete. Drought is caused to high content of carbohydrate, whereas, rain is caused to low content of that. The critical soluble carbohydrate content causing the death of stubble supposed to be 3 to 6% at least. 4. It is suggest that carbohydrate reserves in plant do not play a distinctive role for the regrowth in a summer annual forage like sorghum-sudangrass hybrid, but it might be rather influenced by the other factors, for example, environmental conditions at harvest and new bud.

• Journal of Plant Biotechnology
• /
• v.32 no.4
• /
• pp.287-292
• /
• 2005

Calli were induced by culturing the leaf segment of Actinidia deliciosa ${\times}$ A. arguta clone 118 on MS medium supplemented with 0.5 mg/L 2,4-D, 0.1 mg/L NAA and 0.05 mg/L BA for 8 weeks in light condition. The induced calli were inoculated in liquid MS medium containing 0.5 mg/L 2,4-D, 0.1 mg/L NAA, 0.05 mg/L BA and 3% sucrose to establish cell suspension culture. The cells at the exponential stage and the stationary stage could be observed between 5-11 days and after that 12 days in culture, respectively. The fresh weight of callus induced from the suspended cells did not vary much among the media containing eight different combinations of plant growth regulators tested. The highest frequency of shoot induction (88.3%) was observed in MS medium containing 2.0 mg/L zeatin. Either BA or zeatin mixed with thidiazuron (TDZ) seemed to be effective in shoot induction. The induced shoots were transferred to MS medium containing 0.2 mg/L zeatin for further shoot growth. And then the shoots were transferred to Standardi (ST) medium containing 1.0 mg/L indolebutyric acid (IBA) for rooting. Plantlets could be obtained through cell suspension culture of Actinidia deliciosa ${\times}$ A. arguta clone 118.

• Molecules and Cells
• /
• v.25 no.3
• /
• pp.358-367
• /
• 2008

The embryonic germ cell (EGCs) of mice is a kind of pluripotent stem cell that can be generated from pre- and post-migratory primordial germ cells (PGCs). Most previous studies on DNA methylation of EGCs were restricted to 12.5 days post coitum (dpc). This study was designed to establish and characterize murine EGC lines from migrated PGCs as late as 13.5 dpc and to estimate the degrees of methylation of their imprinted genes as well as of the non-imprinted locus, Oct4, using an accurate and quantitative method of measurement. We established five independent EGC lines from post migratory PGCs of 11.5-13.5 dpc from C57BL/6 ${\times}$ DBA/2 F1 hybrid mouse fetuses. All the EGCs exhibited the typical features of pluripotent cells including hypomethylation of the Oct4 regulatory region. We examined the methylation status of three imprinted genes; Igf2, Igf2r and H19 in the five EGC lines using bisulfite genomic sequencing analysis. Igf2r was almost unmethylated in all the EGC lines irrespective of the their sex and stage of isolation; Igf2 and H19 were more methylated than Igf2r, especially in male EGCs. Moreover, EGCs derived at 13.5 dpc exhibited higher levels of DNA methylation than those from earlier stages. These results suggest that in vitro derived EGCs acquire different epigenotypes from their parental in vivo migratory PGCs, and that sex-specific de novo methylation occurs in the Igf2 and H19 genes of EGCs.

• Journal of Advanced Navigation Technology
• /
• v.8 no.2
• /
• pp.184-190
• /
• 2004

A feedforward linear power amplifier (FLPA) has been developed for UHF-band RFID reader applications. The main and error amplifiers are composed of a 2 stage so that linearity of the FLPA can be improved. The FLPA has been implemented on an FR-4 substrate (Er=4.7 and thickness=0.8 mm) with 3-dB and 10-dB hybrid couplers for input/output power divider and combiner. For 2-tone measurement (input level=-11 dBm at $f_1$=915 MHz and $f_2$=916 MHz), the FLPA exhibits a -18.52 dBm of $IMD_3$, which indicates that $IMD_3$ cancellation with feedforward loop is more than 27 dB. From 890 to 960 MHz, 1-dB gain compression output power and power gain of the FLPA are higher than 30 dBm and 40 dB, respectively.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2009.10a
• /
• pp.393-396
• /
• 2009

This paper describes a design of variable-length FFT/IFFT processor for OFDM-based communication systems. The designed FFT/IFFT processor adopts the in-place single-memory architecture, and uses a hybrid structure of radix-4 and radix-2 DIF algorithms to accommodate FFT lengths of $N=64{\times}2^k$ ($0{\leq}k{\leq}7$). To achieve both memory size reduction and the improved SQNR, a two-step conditional scaling technique is devised, which conditionally scales the intermediate results of each computational stage. The performance analysis results show that the average SQNR's of 64~8,192-point FFT's are over 60-dB. The processor synthesized with a $0.35-{\mu}m$ CMOS cell library can operate with 75-MHz@3.3-V clock, and 64-point and 8,192-point FFT's can be computed in $2.55-{\mu}s$ and $762.7-{\mu}s$, respectively, thus it satisfies the specifications of wireless LAN, DMB, and DVB systems.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.14
• /
• pp.165-172
• /
• 1973

The sterile phenomenon is frequently found in the inter-species hybrids of ginseng as in other plants. It is known that among the hybrids between Panax Ginseng (PG) and Panax Quinquefolium (PQ), and between Panax Ginseng and Paxax Japonicus (PI), PG${\times}$PI is fertile only very rarely, while PG ${\times}$ PQ is always sterile. Therefore, in order to clarify the relationship between this sterility phenomenon and the metabolism of free amino acids, the changes of free amino acids through the formation of the flower organs and seeds of two hybrids, PG ${\times}$ PQ and PG ${\times}$ PI were investigated by thin layer chromatography. The results are summarized as follows: 1. Distinct differences in the quantity and number of free amino acids were recognized between PG ${\times}$ PQ, PG ${\times}$ PI and their parent plants. From the hybrid PG ${\times}$ PQ, 19 kinds of ninhyrin sensitive substances were detected in all. They were (1) 17 amino acids: alanine, valine, leucine, phenylalanine, proline, hydroxy-proline, serine, threonine, tyrosine, aspartic acid, glutamic acid, lysine, arginine, ${\gamma}$-amino butyric acid, ${\beta}$-alanine, cysteic acid and tryptophan, and (2) two amides: asparagine and glutamine. From the hybrid PG ${\times}$ PI, in addition to the above 19 substances, methionine and one unknown substance were detected. 2. Generally, alanine, as partie acid, glutamic acid, cysteic acid and asparagine were detected in large amounts in the two hybrids as in PG, PG and PJ but it was a noticeable fact concerning these two hybrids that the largest quantity of asparagine was found at microspore satge and pollen mature stage. 3. The decrease of cysteic acid in the two hybrids at the red ripened stage was the same as in PQ and PJ but opposite to the change in PG. The detection of methionine in PG ${\times}$ PJ was worthy of notice. 4. The change of proline was conspicuously different from that in their parent plants. It was detected as a trace of color at the micros pore stage while asparagine was detected in the greatest amount at that time. It is well known that the quantity of proline is closely related to the sterility of plant. This fact was also found true in the formation of ginseng seeds. It was reported as well that asparagine accumulated when proline decreased. 5. The deficiency of proline seemed to be closely related with the sterility of hybrids and with the degradation of pollen in anther. 6. The difference in the changes of free amino acids between the selfed lines of PG, PQ and PJ, and their hybrids seemed to be caused by the transformation of gene-action system by hybridization. On these phenomena along with proline metabolim and its physiological role in seed formation further studies are required.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.2 no.2 s.3
• /
• pp.65-72
• /
• 2003

In this work a 6-stage hybrid power amplifier which can be used for the wireless communication systems for MMC(hficrowave Micro Cell) and ITS wireless communication system is designed and fabricated. Ihe power amplifier's each stages was fabricated Hetero-junction Power FET of bare chip type and an alumina substrate with $\varepsilon_{r}$=9.9 and 15-mil thickness. The measured results of power amplifier module showed 33.2$\~$36.5 dB small signal gain, 33.0$\~$34.0 dBm output power at forward frequency (17.6 GHa $\~$ 17.9 CHz) and 36.0$\~$37.0 dB small signal gain, 33.0$\~$34.5 dBm output power at reverse frequency (19.0 GHz $\~$19.2GHz).

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.4
• /
• pp.300-304
• /
• 1991

Several experiments were conducted to elucidate a possibility of sweet sorghum, sugar beet and sugar cane as the resources of bio-energy which were collected from Philipine, India, Japan and Gene -bank in Korea. The experiments were carried out in Chinju, Korea from 1986 to 1988. When sweet sorghum cultivars were taken from 70 to 118 days after sowing on May 20, 1988 upto heading stage, the sugar content of stem was 6 to 14% and yielded 4 to 10ton per l0a in terms of the total fresh weight of plant. Sugar beet root contained 9.2 to 19.8% in sugar producting 3,542 to 6. 397kg per l0a. Meanwhile. the sugar content in stem of sugar cane was 15.2 to 16.7% and final growth the late October in this particular region. Particularly, F1 hybrid cultivar(s-l) of sweet sorghum could be harvested twice in a year. The alcohol quantity obtained from the juice of sweet sorghum was 180$\ell$ per l0a and was increased as sowing date was earlier. The results suggested that it would be possible to utilize the sugar crops as bio-energy resources using improved cultural methods and effective fermentation techniques.

• Journal of Intelligence and Information Systems
• /
• v.19 no.4
• /
• pp.55-79
• /
• 2013

In this paper, we propose a hybrid genetic algorithm (HGA) approach to effectively solve the reverse logistics network with centralized centers (RLNCC). For the proposed HGA approach, genetic algorithm (GA) is used as a main algorithm. For implementing GA, a new bit-string representation scheme using 0 and 1 values is suggested, which can easily make initial population of GA. As genetic operators, the elitist strategy in enlarged sampling space developed by Gen and Chang (1997), a new two-point crossover operator, and a new random mutation operator are used for selection, crossover and mutation, respectively. For hybrid concept of GA, an iterative hill climbing method (IHCM) developed by Michalewicz (1994) is inserted into HGA search loop. The IHCM is one of local search techniques and precisely explores the space converged by GA search. The RLNCC is composed of collection centers, remanufacturing centers, redistribution centers, and secondary markets in reverse logistics networks. Of the centers and secondary markets, only one collection center, remanufacturing center, redistribution center, and secondary market should be opened in reverse logistics networks. Some assumptions are considered for effectively implementing the RLNCC The RLNCC is represented by a mixed integer programming (MIP) model using indexes, parameters and decision variables. The objective function of the MIP model is to minimize the total cost which is consisted of transportation cost, fixed cost, and handling cost. The transportation cost is obtained by transporting the returned products between each centers and secondary markets. The fixed cost is calculated by opening or closing decision at each center and secondary markets. That is, if there are three collection centers (the opening costs of collection center 1 2, and 3 are 10.5, 12.1, 8.9, respectively), and the collection center 1 is opened and the remainders are all closed, then the fixed cost is 10.5. The handling cost means the cost of treating the products returned from customers at each center and secondary markets which are opened at each RLNCC stage. The RLNCC is solved by the proposed HGA approach. In numerical experiment, the proposed HGA and a conventional competing approach is compared with each other using various measures of performance. For the conventional competing approach, the GA approach by Yun (2013) is used. The GA approach has not any local search technique such as the IHCM proposed the HGA approach. As measures of performance, CPU time, optimal solution, and optimal setting are used. Two types of the RLNCC with different numbers of customers, collection centers, remanufacturing centers, redistribution centers and secondary markets are presented for comparing the performances of the HGA and GA approaches. The MIP models using the two types of the RLNCC are programmed by Visual Basic Version 6.0, and the computer implementing environment is the IBM compatible PC with 3.06Ghz CPU speed and 1GB RAM on Windows XP. The parameters used in the HGA and GA approaches are that the total number of generations is 10,000, population size 20, crossover rate 0.5, mutation rate 0.1, and the search range for the IHCM is 2.0. Total 20 iterations are made for eliminating the randomness of the searches of the HGA and GA approaches. With performance comparisons, network representations by opening/closing decision, and convergence processes using two types of the RLNCCs, the experimental result shows that the HGA has significantly better performance in terms of the optimal solution than the GA, though the GA is slightly quicker than the HGA in terms of the CPU time. Finally, it has been proved that the proposed HGA approach is more efficient than conventional GA approach in two types of the RLNCC since the former has a GA search process as well as a local search process for additional search scheme, while the latter has a GA search process alone. For a future study, much more large-sized RLNCCs will be tested for robustness of our approach.

• Applied Biological Chemistry
• /
• v.49 no.3
• /
• pp.186-191
• /
• 2006

In the present study, an attempt has been made to produce hybrid yeast strains of different useful and dominant characteristics. The hybrid yeast strains were produced by electrofusion and their genetic analysis were performed by RAPD-PCR (random amplified polymorphic DNA-polymerase chain reaction). The protoplast of Saccharomyces cerevisiae KCTC 7904 and Zygosaccharomyces rouxii KCTC 7966 were obtained above 92% when treated with lyticase at $30^{\circ}C$ for $60{\sim}90$ min after the pretreatment of $1{\sim}2%$ 2-mercaptoethanol at $30^{\circ}C$ for $15{\sim}20$ min. The fusant was produced from paired protoplast stage under the electric pulse at high frequency conditions (1.5 MHz/50 pV, 615 $V/256\;{\mu}sec$) within glass-platinum made electrofusion chamber. Changes in RAPD patterns in mother cells and hybrid cells proved that the fusant contains two types of yeast gene originated from its parent. Furthermore, fermentation characters exhibits by the fusant cell confirmed its genetic changes. These results suggest that genetically stable hybrid yeast strains of economic importance can be produced by electrofusion technique and these electrofused yeast cells have an enormous impact in biotechnology and biomedicine.