• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.252-252
• /
• 2017

Nowadays water shortage is becoming one of the biggest problems in the Korea. Many different methods are developed for conservation of water. Soil water management has become the most indispensable factor for augmenting the crop productivity especially on soybean (Glycine max L.) because of their high susceptibility to both water stress and water logging at various growth stages. The farmers have been using irrigation techniques through manual control which farmers irrigate lands at regular intervals. Automatic irrigation systems are convenient, especially for those who need to travel. If automatic irrigation systems are installed and programmed properly, they can even save you money and help in water conservation. Automatic irrigation systems can be programmed to provide automatic irrigation to the plants which helps in saving money and water and to discharge more precise amounts of water in a targeted area, which promotes water conservation. The objective of this study was to determine the possible effect of automatic irrigation systems based on soil moisture on soybean growth. This experiment was conducted on an upland field with sandy loam soils in Department of Southern Area Crop, NICS, RDA. The study had three different irrigation methods; sprinkle irrigation (SI), surface drip irrigation (SDI) and fountain irrigation (FI). SI was installed at spacing of $7{\times}7m$ and $1.8m^3/hr$ as square for per irrigation plot, a lateral pipe of SDI was laid down to 1.2 m row spacing with $2.3L\;h^{-1}$ discharge rate, the distance between laterals was 20 cm spacing between drippers and FI was laid down in 3m interval as square for per irrigation plot. Soybean (Daewon) cultivar was sown in the June $20^{th}$, 2016, planted in 2 rows of apart in 1.2 m wide rows and distance between hills was 20 cm. All agronomic practices were done as the recommended cultivation. This automatic irrigation system had valves to turn irrigation on/off easily by automated controller, solenoids and moisture sensor which were set the reference level as available soil moisture levels of 30% at 10cm depth. The efficiency of applied irrigation was obtained by dividing the total water stored in the effective root zone to the applied irrigation water. Results showed that seasonal applied irrigation water amounts were $60.4ton\;10a^{-1}$ (SI), $47.3ton\;10a^{-1}$ (SDI) and $92.6 ton\;10a^{-1}$ (FI), respectively. The most significant advantage of SDI system was that water was supplied near the root zone of plants drip by drip. This system saved a large quantity of water by 27.5% and 95.6% compared to SI, FI system. The average soybean yield was significantly affected by different irrigation methods. The soybean yield by different irrigation methods were $309.7kg\;10a^{-1}$ from SDI $282.2kg\;10a^{-1}$ from SI, $289.4kg\;10a^{-1}$ from FI, and $206.3kg\;10a^{-1}$ from control, respectively. SDI resulted in increase of soybean yield by 50.1%, 7.0% 9.8% compared to non-irrigation (control), FI and SI, respectively. Therefore, the automatic irrigation system supplied water only when the soil moisture in the soil went below the reference. Due to the direct transfer of water to the roots water conservation took place and also helped to maintain the moisture to soil ratio at the root zone constant. Thus the system is efficient and compatible to changing environment. The automatic irrigation system provides with several benefits and can operate with less manpower. In conclusion, improving automatic irrigation system can contribute greatly to reducing production costs of crops and making the industry more competitive and sustainable.

• Korean Journal of Environmental Biology
• /
• v.22 no.1
• /
• pp.93-100
• /
• 2004

The content of nutrients such as organic carbon, nitrogen, phosphorus and potassium accumulated on soil layers in Quercus mongolica forest of Mt. Songnisan National Park located at central part of Korea was measured, and then the decomposition constants and decay times of the nutrients were also calculated by the negative coefficience model(O1son,1963). The quantities of organic carton of L-layer, F-layer, H-layer and $A_1$-layer of the forest stand were 231.25 g $m^{-2}$, 291.50 g $m^{-2}$,166.91 g$m^{-2}$ and 174.51 g $m^{-2}$, respectively. The content of organic carbon and nitrogen contained in L-layer and F-layer showed large quantity than those of other layers. The large amount of phosphorus and potassium was observed at the B-layer and $A_1$-layer. On the other hand, the decomposition constants(k) of soil organic matter were as follows : organic carbon (k = 0.3657), nitrogen (k = 0.3319), phosphorus (k = 0.2050), and potassium (k = 0.0934) and the decay times needed to 99% decomposition of nutrients in soil organic matter were as follows: that is, organic carton, nitrogen, phosphorus and potassium was 13.94 years, 15.18 years, 24.79 years, and 55.11 years, respectively. By the application of Turbo Pascal Program on the inflowed and outflowed nutrients to the forest stand,87.67% (714.84 g $m^{-2}$) of organic carbon inflowed was decomposed and 81.62% (1,594.62 g $m^{-2}$) of organic carbon accumulated was decomposed. And 84.98% of nitrogen inflowed was decomposed and 70.26% of nitrogen accumulated was also decayed.50.00% of phosphorus input and 40.31% of potassium input were decomposed, and 38.40% of phosphoyus and 33.03% of potassium accumulated were also decayed, respectively. Therefore, it is suggested that Quercus mongolica forest surveyed in the present study is maintaining in steady state because input and output amounts of nutrients is shown a similar pattern.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.10 no.3
• /
• pp.189-198
• /
• 2000

The stochiometric mixture of evaporating materials for the $CuGaSe_2$single crystal thin films were prepared from horizontal furnace. Using extrapolation method of X-ray diffraction patterns for the polycrystal $CuGaSe_2$, it was found tetragonal structure whose lattice constant $a_0}$ and $c_0$ were 5.615 $\AA$ and 11.025 $\AA$, respectively. To obtains the single crystal thin films, $CuGaSe_2$mixed crystal was deposited on throughly etched GaAs(100) by the Hot Wall Epitaxy (HWE) system. The source and substrate temperature were $610^{\circ}C$ and $450^{\circ}C$ respectively, and the growth rate of the single crystal thin films was about 0.5$\mu\textrm{m}$/h. The crystalline structure of single crystal thin films was investigated by the double crystal X-ray diffraction (DCXD). Hall effect on this sample was measured by the method of van der Pauw and studied on carrier density and mobility depending on temperature. From Hall data, the mobility was likely to be decreased by pizoelectric scattering in the temperature range 30 K to 150 K and by polar optical scattering in the temperature range 150 K to 293 K. The optical energy gaps were found to be 1.68 eV for CuGaSe$_2$sing1e crystal thin films at room temperature. The temperature dependence of the photocurrent peak energy is well explained by the Varshni equation then the constants in the Varshni equation are given by $\alpha$ = $9.615{\times}10^{-4}$eV/K, and $\beta$ = 335 K. From the photocurrent spectra by illumination of polarized light of the $CuGaSe_2$single crystal thin films. We have found that values of spin orbit coupling $\Delta$So and crystal field splitting $\Delta$Cr was 0.0900 eV and 0.2498 eV, respectively. From the PL spectra at 20 K, the peaks corresponding to free bound excitons and D-A pair and a broad emission band due to SA is identified. The binding energy of the free excitons are determined to be 0.0626 eV and the dissipation energy of the acceptor-bound exciton and donor-bound exciton to be 0.0352 eV, 0.0932 eV, respectively.

• Journal of Intelligence and Information Systems
• /
• v.17 no.2
• /
• pp.97-107
• /
• 2011

Nowadays there are a lot of issues about copyright infringement in the Internet world because the digital content on the network can be copied and delivered easily. Indeed the copied version has same quality with the original one. So, copyright owners and content provider want a powerful solution to protect their content. The popular one of the solutions was DRM (digital rights management) that is based on encryption technology and rights control. However, DRM-free service was launched after Steve Jobs who is CEO of Apple proposed a new music service paradigm without DRM, and the DRM is disappeared at the online music market. Even though the online music service decided to not equip the DRM solution, copyright owners and content providers are still searching a solution to protect their content. A solution to replace the DRM technology is digital audio watermarking technology which can embed copyright information into the music. In this paper, the author proposed a new audio watermarking algorithm with two approaches. First, the watermark information is generated by two dimensional barcode which has error correction code. So, the information can be recovered by itself if the errors fall into the range of the error tolerance. The other one is to use chirp sequence of CDMA (code division multiple access). These make the algorithm robust to the several malicious attacks. There are many 2D barcodes. Especially, QR code which is one of the matrix barcodes can express the information and the expression is freer than that of the other matrix barcodes. QR code has the square patterns with double at the three corners and these indicate the boundary of the symbol. This feature of the QR code is proper to express the watermark information. That is, because the QR code is 2D barcodes, nonlinear code and matrix code, it can be modulated to the spread spectrum and can be used for the watermarking algorithm. The proposed algorithm assigns the different spread spectrum sequences to the individual users respectively. In the case that the assigned code sequences are orthogonal, we can identify the watermark information of the individual user from an audio content. The algorithm used the Walsh code as an orthogonal code. The watermark information is rearranged to the 1D sequence from 2D barcode and modulated by the Walsh code. The modulated watermark information is embedded into the DCT (discrete cosine transform) domain of the original audio content. For the performance evaluation, I used 3 audio samples, "Amazing Grace", "Oh! Carol" and "Take me home country roads", The attacks for the robustness test were MP3 compression, echo attack, and sub woofer boost. The MP3 compression was performed by a tool of Cool Edit Pro 2.0. The specification of MP3 was CBR(Constant Bit Rate) 128kbps, 44,100Hz, and stereo. The echo attack had the echo with initial volume 70%, decay 75%, and delay 100msec. The sub woofer boost attack was a modification attack of low frequency part in the Fourier coefficients. The test results showed the proposed algorithm is robust to the attacks. In the MP3 attack, the strength of the watermark information is not affected, and then the watermark can be detected from all of the sample audios. In the sub woofer boost attack, the watermark was detected when the strength is 0.3. Also, in the case of echo attack, the watermark can be identified if the strength is greater and equal than 0.5.

• Progress in Medical Physics
• /
• v.16 no.1
• /
• pp.10-15
• /
• 2005

IAEA's guidance levels have been provided for western people to the end. Guidance levels lower than the IAEA'S will be necessary in view of Korean people's proportions. Therefore, we need to develope the standard doses for Korean people. And we conducted a nationwide survey of patient dose from x-ray examinations in Korea. In this study, the 278 institutions were selected from Members Book of Korean Hospital Association. The valid response rate was approximately 57.9%. Doses were calculated from the questionnaires by NDD method. We obtained the results were as follows; 1) General radiographic equipments were distributed for 42.0%, fluoroscopic equipments 29.4%, dental equipments 13.2%, CT units 8.1 % and mamographic units 7.2%. 2) According to classification by rectification, three-phase equipments were 29.9%, inverter-type generators 29.5%, single-phase equipments 25.5%, constant voltage units 9.0% and unknown units 6.0%. 3) According to classification by receptor system, film-screen types were 46.8%, CR types 26.8%, DR types 17.7% and unknown types 8.9%. 4) The number of examinations were chest 49.2%, spine 16.8% and abdomen 12.7%. 5) Patient doses were head AP 3.44 mGy, abdomen AP 4.25 mGy and chest PA 0.39 mGy.

• Journal of the Mineralogical Society of Korea
• /
• v.25 no.4
• /
• pp.197-210
• /
• 2012

Hematite has been known to be the most stable form of various iron (oxyhydr)oxides in the surface environments. In this study, its properties as an adsorbent were examined and also adsorption of arsenic onto hematite was characterized as well. The specific surface area of hematite synthesized in our laboratory appeared to be $31.8g\;m^2/g$ and its point of zero salt effect, (PZSE) determined by potentiometric titration was observed 8.5. These features of hematite may contribute to high capacity of arsenic adsorption. From several adsorption experiments undertaken at the identical solution concentrations over pH 2~12, the adsorption of As(III) (arsenite) was greater than that of As(V) (arsenate). As of pH-dependent adsorption patterns, in addition, arsenite adsorption gradually increased until pH 9.2 and then sharply decreased with pH, whereas adsorption of arsenate was greatest at pH 2.0 and steadily decreased with the increasing pH from 2 to 12. The characteristics of these pH-dependent adsorption patterns might be caused by combined effects of the variation in the chemical speciation of arsenic and the surface charge of hematite. The experimental results on adsorption kinetics show that adsorption of both arsenic species onto hematite approached equilibrium within 20 h. Additionally, the pseudo-second-order model was evaluated to be the best fit for the adsorption kinetics of arsenic onto hematite, regardless of arsenic species, and the rate constant of As(V) adsorption was investigated to be larger than that of As(III).

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.18 no.5
• /
• pp.455-463
• /
• 1985

Thermal-denaturation of myofibrillar protein of dorsal skeletal muscle from file fish was investigated by measuring denaturation constant($K_D$) and thermodynamic parameters at various temperatures. The protective effects of sucrose, sorbitol and amino acids when added individually or combined were also discussed. The denaturation rate as reflected in inactivation of myofibrillar protein Ca-ATPase was followed the first order reaction. The $K_D$ values at $25^{\circ}C,\;30^{\circ}C,\;and\;35^{\circ}C$ were $19.52{\times}10^{-5},\;112.25{\times}10^{-5},\;and\;247.20{\times}10^{-5}$, respectively. The activation energy of the reaction at $30^{\circ}C$ was 43 kcal/mole. The protective effects of sucrose, sorbitol, glycine, alanine and Na-glutamate were increased with the concentration but the effects of sorbitol and Na-glutamate decreased beyond 1.0 mole. Basic amino acids such as arginine and lysine did not revealed any protective effect on the thermal denaturation. In case of mixed addition, the effects of Na-glutamate to glycine, sorbitol to glycine, and sorbitol to sucrose or sorbitol to Na-glutamate were enhanced 1.2 to 7.0 times as much as that of control (ratio of mixing; 1:1, range of concentration; 0.5 to 1.25 mole). Under the frozen condition at $-20^{\circ}C$, two mixtures such as Na-glutamate to glycine and sorbitol to sucrose apparently revealed the protective effects.

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.8
• /
• pp.844-851
• /
• 2005

The purpose of this study was to determine feasibility of application of regenerated or recycled $TiO_2$ on the successive treatment of Cu(II)-EDTA. The recovery of copper, the reuse of $TiO_2$ and the assessment of acute toxicity was studied in the total eight successive photocatalytic reactions. Aqueous solution of $10^{-4}\;M$ Cu(II)-EDTA was treated using an illuminated $TiO_2$ at pH 6 in a circulating reactor. Two different procedures were applied in the reuse of $TiO_2$: i) recycle of $TiO_2$ without acid wash ii) regeneration of $TiO_2$ with acid wash to remove adsorbed copper in a previous experiment. The averaged decomplexation rate constant($k'_{obs}$) of Cu(II)-EDTA in recycle of $TiO_2$ without acid wash was approximately 45% less than that in regeneration of $TiO_2$ with acid wash. Removal of Cu(II) was near complete after 180 minutes in the total eight successive photocatalytic reactions using the regenerated $TiO_2$ after acid wash. In contrast, removal of Cu(II) was minimum at total fifth successive photocatalytic oxidation using the recycled $TiO_2$ without arid wash. The recovered $TiO_2$ was approximately 86% in average in each procedure. The recovered Cu(II) was 67.9% in average. The acute relative toxicity of the treated water rapidly declined at an initial reaction time up to 60 minutes but little declination was observed after 60 minutes due to little degradation of DOC. Relative toxicity of treated water using the recycled $TiO_2$ without acid wash we some what well correlated with the concentration of dissolved Cu(II). From this work, it is suggested that Cu(II)-EDTA can be effectively treated using an integrated cyclic photocatalytic oxidation with recovery of $TiO_2$ and Cu(II).

• Journal of Korean Society of Environmental Engineers
• /
• v.30 no.3
• /
• pp.323-330
• /
• 2008

The study presents the results of 1,4-dioxane degradation using zero valent (Fe$^0$) or Fe$^{2+}$ ions with and without UV. During the reaction, the change of [Fe$^{2+}$] and [Fe$^{2+}$]/[Fe(t)], the concentration ratio of ferrous ion to total iron ion in solution was measured. Less than 10% degradation of 1,4-dioxane was observed by UV-only, Fe$^0$-only, and Fe$^{2+}$-only conditions, and also the changes of [Fe$^{2+}$] and [Fe$^{2+}$]/[Fe(t)] were minimal in each reaction. However, the oxidation of Fe$^0$ was enhanced with the irradiation of UV by approximately 25% and the improvement of 1,4-dioxane degradation was observed. Fenton reaction ($Fe^{2+}+H_2O_2$) showed higher degradation efficiency of 1,4-dioxane until 90 min, which of the degradation was stopped after that time. In the reaction of Fe$^{2+}$ and UV, the ratio of [Fe$^{2+}$]/[Fe(t)] decreased then slowly increased after a certain time indicating the reduction of Fe3+ to Fe$^{2+}$. In case of Fe$^0$ in the presence of UV, the first-order rate constant was found to be 1.84$\times$10$^{-3}$ min$^{-1}$ until 90 min, and then changed to 9.33$\times$10$^{-3}$ min$^{-1}$ when the oxidation of Fe$^{2+}$ mainly occurred. In this case [Fe$^{2+}$]/[Fe(t)] kept decreasing for the reaction. However, the addition of perchlortae (ClO$_4^-$) in the reaction of Fe$^0$ and UV induced the continuous increase of [Fe$^{2+}$]/[Fe(t)] ratio. The results mean the primary degradation factor of 1,4-dioxane is the oxidation by the radicals generated from the redox reaction between Fe$^{2+}$ and Fe$^{3+}$. Also, both UV and ClO$_4^-$ played the role inducing the reduction of Fe$^{3+}$, which is important to degrade 1,4-dioxane by enhancing the generation of radicals.

• Radiation Oncology Journal
• /
• v.12 no.1
• /
• pp.27-31
• /
• 1994

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.