• The Journal of Natural Sciences
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• v.5 no.1
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• pp.67-75
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• 1992

In the our country, especially in Yeongil and Wolsung area, abundant authigenic zeolites are found from the tuffaceous sediments and volcanic rocks of Miocene age showing wide variation in their mineralogy and abundance from horizon to horizon. The principal zeolite species identified are clinopti-lolite. mordenite. heulandite. ferrierite, and erionite. etc. Zeolite minerals are widely used in many countries in the following applications; (a) in air separation adsorption processes; (b)as desiccants; (c)in inorganic building materials; (d)in papermaking; (e)in fertilizers; (f)as soilconditioners-this application is based upon the ability of the zeolite to ion exchange with soil nutrients; (g)in the treatment of radioactive wastes; and (h)as adsorbents for toxic gases, etc. In the present paper, using natural zeolite mordenite treated with IN hydrochloric acid or IN sodium chloride solution as column packings, separation characteristics of argon, nitrogen, carbon monoxide, and methane gases have been studied by gas chromatography. By the use of mordenite treated with hydrochloric acid solution, the tailing peak of methane showed from untreated mordenite was satisfactorily reduced, although it was difficult to separate it from carbon monoxide with a column activated at $300^{\circ}C$. Using a column activated at $350^{\circ}C$, methane could be separated from carbon monoxide easily but only carbon monoxide eluted as a bad defined peak. Mordenite treated with sodium chloride solution was generally similar to chromatograms obtained by using the untreated mordenite. Both the above chemical treatments of mordenite had little effect on the separations of argon and nitrogen. The separations and the HETP values obtained from natural zeolite mordenite treated with continuously hydrochloric acid and sodium chloride solutions were almost identical with those obtained with synthetic molecular sieve 5A zeolite. On the other hand, the efficiency of column was good in the range 20~3Oml/min of the carrier helium gas rate.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.423-430
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• 2011

This study was carried out to examine the nutritive values and quality of agricultural bag (AG-BAG) silage manufactured with corn grown in reclaimed paddy field of Sukmoon at Dangjin Province in Korea. The cultivars of silage corn used in this experiment 1 were both Kwangpyungok and P32B33. The fertilizer were applied with the amounts of customary applications (200 kg N/ha, 150 kg $P_2O_5$/ha and 150 kg $K_2O$/ha). The content of moisture in corn AG-BAG silage ranged from 68 to 79%. The pH in corn AG-BAG silage stages ranged from 3.49 to 3.65 and was not influenced by the harvest time. The contents of crude protein (CP) in corn AG-BAG silage decreased with delayed harvest time. However, the contents of ADF (acid detergent fiber) and NDF (neutral detergent fiber) increased. The content of lactic acid increased with delayed harvest time, but the content of acetic acid decreased. Therefore, we suggest that the system of AG-BAG silage can improve the quality of corn silage and be one of the economical and effective methods to manufacture corn silage.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.258-292
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• 1996

In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.360-371
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• 2018

Extracts and fractions of Anemarrhena asphodeloides Bunge were prepared and their physiological activities and components were analyzed. Antimicrobial activities of the ethyl acetate and aglycone fractions were $78{\mu}g/ml$ and $31{\mu}g/ml$, respectively, for Staphylococcus aureus and $156{\mu}g/ml$ and $125{\mu}g/ml$, respectively, for Pseudomonas aeruginosa. 1,1-Diphenyl-2-picrylhydrazyl free radical scavenging activities ($FSC_{50}$) of 50% ethanol extract, ethyl acetate fraction, and aglycone fraction of A. asphodeloides extracts were $146.2{\mu}g/ml$, $23.19{\mu}g/ml$, and $71.06{\mu}g/ml$, respectively. The total antioxidant capacity ($OSC_{50}$) in an $Fe^{3+}$-EDTA/hydrogen peroxide ($H_2O_2$) system were $17.5{\mu}g/ml$, $1.5{\mu}g/ml$, and $1.4{\mu}g/ml$, respectively. The cytoprotective effect (${\tau}_{50}$) in $^1O_2$-induced erythrocyte hemolysis was 181 min with $4{\mu}g/ml$ of the aglycone fraction. The ${\tau}_{50}$ of the aglycone fraction was approximately 4-times higher than that of (+)-${\alpha}$-tocopherol (${\tau}_{50}$, 41 min). Analysis of $H_2O_2$-induced damage of HaCaT cells revealed that the maximum cell viabilities for the 50% ethanol extract, ethyl acetate fraction, and aglycone fraction were 86.23%, 86.59%, and 89.70%, respectively. The aglycone fraction increased cell viability up to 11.53% at $1{\mu}g/ml$ compared to the positive control treated with $H_2O_2$. Analysis of ultraviolet B radiation-induced HaCaT cell damage revealed up to 41.77% decreased intracellular reactive oxygen species in the $2{\mu}g/ml$ aglycone fraction compared with the positive control treated with ultraviolet B radiation. The findings suggest that the extracts and fractions of A. asphodeloides Bunge have potential applications in the field of cosmetics as natural preservatives and antioxidants.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.4B
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• pp.646-680
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• 2000

In this paper, we discuss the design and implementation of a concurrency control manager for a main memory DBMS(MMDBMS). Since an MMDBMS, unlike a disk-based DBMS, performs all of data update or retrieval operations by accessing main memory only, the portion of the cost for concurrency control in the total cost for a data update or retrieval is fairly high. Thus, the development of an efficient concurrency control manager highly accelerates the performance of the entire system. Our concurrency control manager employs the 2-phase locking protocol, and has the following characteristics. First, it adapts the partition, an allocation unit of main memory, as a locking granule, and thus, effectively adjusts the trade-off between the system concurrency and locking cost through the analysis of applications. Second, it enjoys low locking costs by maintaining the lock information directly in the partition itself. Third, it provides the latch as a mechanism for physical consistency of system data. Our latch supports both of the shared and exclusive modes, and maximizes the CPU utilization by combining the Bakery algorithm and Unix semaphore facility. Fourth, for solving the deadlock problem, it periodically examines whether a system is in a deadlock state using lock waiting information. In addition, we discuss various issues arising in development such as mutual exclusion of a transaction table, mutual exclusion of indexes and system catalogs, and realtime application supports.

• Horticultural Science & Technology
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• v.33 no.2
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• pp.242-250
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• 2015

Insertional mutagenesis induced by T-DNA or transposon tagging offers possibilities for analysis of gene function. However, its potential remains limited unless good methods for detecting the target locus are developed. We describe a PCR technique for efficient identification of DNA sequences adjacent to the inserted T-DNA in a higher plant, Chinese cabbage (Brassica rapa ssp. pekinensis). This strategy, which we named variable argument thermal asymmetric interlaced PCR (VA-TAIL PCR), was designed by modifying a single-step annealing-extension PCR by including a touch-up PCR protocol and using long gene-specific primers. Amplification efficiency of this PCR program was significantly increased by employing an autosegment extension method and linked sequence strategy in nested long gene-specific primers. For this technique, arbitrary degenerate (AD) primers specific to B. rapa were designed by analyzing the Integr8 proteome database. These primers showed higher accuracy and utility in the identification of flanking DNA sequences from individual transgenic Chinese cabbages in a large T-DNA inserted population. The VA-TAIL PCR method described in this study allows the identification of DNA regions flanking known DNA fragments. This method has potential biotechnological applications, being highly suitable for identification of target genomic loci in insertional mutagenesis screens.

• The Korea Journal of Herbology
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• v.25 no.4
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• pp.161-169
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• 2010

Objectives & Methods : To compare the medicinal herbs between Ayurvedic medicine and traditional Korean medicine(TKM), we took reference of major publications related to Ayurvedic medicinal herbs such as Indian Herbal Remedies, Prime Ayurvedic Plant Drugs, with those of TKM. We selected most widely used 130 herbal species of Ayurvedic medicine and compared the similarities and differences with TKM. Comparative factors were the origin, habitation, synonyms, usage, medicinal parts, and precautions. Results : 1. The medicinal herbs Resinatum Lignum(沈香), Arecae Pericarpium(大腹皮), Arecae Semen(檳榔), Carthami Flos (紅花), Camphorum(樟腦), Crotonis Semen(巴豆), Curculiginis Rhizoma(仙茅) used in TKM did exactly correlate in their origins with those of Ayurvedic medicine. 2. Varieties of allied species were found in their origins. Benincasae Pericarpium(冬瓜皮), and Benincasae Semen(冬瓜子) derive from the same plant Benincasa hispida Cogn. for both Ayurvedic medicine and TKM. Interestingly, B. cerifera Savi. is also claimed for same uses in Ayurvedic medicine. This broadened use of allied species is found in various Ayurvedic herbal medicine such as Cannabis Semen(火麻仁) using Cannabis indica Lam., and Curcuma Longae Rhizoma(薑黃) using Curcuma domestica Valeton. This suggests the possibility of their usage also in TKM. 3. Myrrha(沒藥), and Curculiginis Rhizoma concorded their usage with TKM. While Arecae Pericarpium(大腹皮), Arecae Semen(檳榔), Aquilariae Resinatum Lignum(沈香), Pericarpium(冬瓜皮), Benincasae Semen(冬瓜子), Cannabis Semen(火麻仁), Carthami Flos(紅花), Camphorum(樟腦), Crotonis Semen(巴豆), Curcumae Radix(鬱金), Curcuma Longae Rhizoma(薑黃) and Zedoariae Rhizoma(莪朮) revealed varied efficacies according to their part used or usage forms. Conclusion : Both Ayurvedic medicine and TKM reflect the traditional medicine of its regions where is founded. Mutual understanding improves the capability of coping of diverse ailments of present days and also replacing some plants in the days of increasing threat to our environment. Abundant external applications of various plants found in Ayurvedic medicine were particularly useful for TKM to complement its strength in herbal intake.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.39-44
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• 2002

The current study was conducted to investigate the effects of administration of antiserum against adipocyte plasma membrane(APM) proteins into rats on body fat mass. Twenty(20) male adult Sprague-Dawley rats were randomly allocated into either control or antiserum treatment group(10 rats/treatment) and immunized with physiological saline(control group) and polyclonal antiserum (treatment group), respectively, raised in sheep against rat APM proteins(5times, 2day interval). All animals were killed 4weeks after last injection. Intraperitoneal(i.p.) administration of antiserum significantly(P=0.0054 and P=0.0019, respectively) reduced subcutaneous(21.9%) and perirenal + mesentric + epididymic(36.0%) adipose tissue mass in rats of treatment group. Although body weights of antiserum treated rats were decreased during immunization, the rats recovered their body weight after 1 week of treatment. There were no significant changes in the level of blood glucose and in the contents of muscle protein and fat in antiserum treated animals. Current results indicate that polyclonal antibodies against APM proteins could be used to manipulate body fat mass in meat animals as well as laboratory animals. Further studies, however, are necessary for the practical applications of the current results.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.44 no.1
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• pp.26-39
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• 2007

In recent years, rate control is an important technique in real time video communication applications using H.264/AVC. Many existing rate control algorithms employ the quadratic rate-distortion model, which is determine the target bits for each P frame. In this paper, a new rate control algorithm for transmission of H.264/AVC video bit stream through CBR(Constant Bit Rate) channel is proposed. The proposed algorithm predicts an adaptive QP(Quantization Parameter) for improving video distortion, due to high motion and abruptly scene change, which target bit rate and MAD(Mean of Absolute Difference) for current frame considering image complexity variance between previous and current frames. Additionally, it uses frame skip technique to maintain bit stream within a manageable range and protect buffer from overflow or underflow. Experimental results show that the proposed method gives a quality improvement of about 0.5dB when compared to previous rate control algorithm. Also our proposed algorithm encodes the video sequences with less frame skipping compared to the existing rate control for H.264/AVC.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.250-250
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• 2012

Recently, multiferroic materials have attracted much attention due to their fascinating fundamental physical properties and potential technological applications in magnetic/ferroelectric data storage systems, quantum electromagnets, spintronics, and sensor devices. Among single-phase multiferroic materials, $BiFeO_3$, in particular, has received considerable attention because of its very interesting magnetoelectric properties for application to spintronics. Enhanced ferromagnetism was found by Fe-site ion substitution with magnetic ions. In this study, $BiFe_{1-x}Ni_xO_3$ (x=0 and 0.05) bulk ceramic compounds were prepared by solid-state reaction and rapid sintering. High-purity $Bi_2O_3$, $Fe_3O_4$ and NiO powders were mixed with the stoichiometric proportions, and calcined at $450^{\circ}C$ for 24 h to produce $BiFe_{1-x}Ni_xO_3$. Then, the samples were directly put into the oven, which was heated up to $800^{\circ}C$ and sintered in air for 20 min. The crystalline structure of samples was investigated at room temperature by using a Rigaku Miniflex powder diffractometer. The Raman measurements were carried out with a Raman spectrometer with 514.5-nm-excitation Ar+-laser source under air ambient condition on a focused area of $1-{\mu}m$ diameter. The field-dependent magnetization and the temperature-dependent magnetization measurements were performed with a vibrating-sample magnetometer. The x-ray diffraction study demonstrates the compressive stress due to Ni substitution at the Fe site. $BiFe_{0.95}Ni_{0.05}O_3$ exhibits the rhombohedral perovskite structure R3c, similar to $BiFeO_3$. The lattice constant of $BiFe_{0.95}Ni_{0.05}O_3$ is smaller than of $BiFeO_3$ because of the smaller ionic radius of Ni3+ than that of Fe3+. The field-dependent magnetization of $BiFe_{0.95}Ni_{0.05}O_3$ exhibits a clear hysteresis loop at 300 K. The magnetic properties of $BiFe_{0.95}Ni_{0.05}O_3$ were improved at room temperature because of the existence of structurally compressive stress.