• Journal of the Korean Wood Science and Technology
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• v.2 no.2
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• pp.8-12
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• 1974

1. If one unity is given to the prongs whose ends touch each other for estimating the internal stresses occuring in it, the internal stresses which are developed in the open prongs can be evaluated by the ratio to the unity. In accordance with the above statement, an equation was derived as follows. For employing this equation, the prongs should be made as shown in Fig. I, and be measured A and B' as indicated in Fig. l. A more precise value will result as the angle (J becomes smaller. $CH=\frac{(A-B') (4W+A) (4W-A)}{2A[(2W+(A-B')][2W-(A-B')]}{\times}100%$ where A is thickness of the prong, B' is the distance between the two prongs shown in Fig. 1 and CH is the value of internal stress expressed by percentage. It precision is not required, the equation can be simplified as follows. $CH=\frac{A-B'}{A}{\times}200%$ 2. Under scheduled drying condition III the kiln, when the weight of a sample board is constant, the moisture content of the shell of a sample board in the case of a normal casehardening is lower than that of the equilibrium moisture content which is indicated by the Forest Products Laboratory, U. S. Department of Agriculture. This result is usually true, especially in a thin sample board. A thick unseasoned or reverse casehardened sample does not follow in the above statement. 3. The results in the comparison of drying rate with five different kinds of wood given in Table 1 show that the these drying rates, i.e., the quantity of water evaporated from the surface area of I centimeter square per hour, are graded by the order of their magnitude as follows. (1) Ginkgo biloba Linne (2) Diospyros Kaki Thumberg. (3) Pinus densiflora Sieb. et Zucc. (4) Larix kaempheri Sargent (5) Castanea crenata Sieb. et Zucc. It is shown, for example, that at the moisture content of 20 percent the highest value revealed by the Ginkgo biloba is in the order of 3.8 times as great as that for Castanea crenata Sieb. & Zucc. which has the lowest value. Especially below the moisture content of 26 percent, the drying rate, i.e., the function of moisture content in percentage, is represented by the linear equation. All of these linear equations are highly significant in testing the confficient of X i. e., moisture content in percentage. In the Table 2, the symbols are expressed as follows; Y is the quantity of water evaporated from the surface area of 1 centimeter square per hour, and X is the moisture content of the percentage. The drying rate is plotted against the moisture content of the percentage as in Fig. 2. 4. One hundred times the ratio(P%) of the number of samples occuring in the CH 4 class (from 76 to 100% of CH ratio) within the total number of saplmes tested to those of the total which underlie the given SR ratio is measured in Table 3. (The 9% indicated above is assumed as the danger probability in percentage). In summarizing above results, the conclusion is in Table 4. NOTE: In Table 4, the column numbers such as 1. 2 and 3 imply as follows, respectively. 1) The minimum SR ratio which does not reveal the CH 4, class is indicated as in the column 1. 2) The extent of SR ratio which is confined in the safety allowance of 30 percent is shown in the column 2. 3) The lowest limitation of SR ratio which gives the most danger probability of 100 percent is shown in column 3. In analyzing above results, it is clear that chestnut and larch easly form internal stress in comparison with persimmon and pine. However, in considering the fact that the revers, casehardening occured in fir and ginkgo, under the same drying condition with the others, it is deduced that fir and ginkgo form normal casehardening with difficulty in comparison with the other species tested. 5. All kinds of drying defects except casehardening are developed when the internal stresses are in excess of the ultimate strength of material in the case of long-lime loading. Under the drying condition at temperature of $170^{\circ}F$ and the lower humidity. the drying defects are not so severe. However, under the same conditions at $200^{\circ}F$, the lower humidity and not end coated, all sample boards develop severe drying defects. Especially the chestnut was very prone to form the drying defects such as casehardening and splitting.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.171-180
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• 2001

Purpose : Expression of TIMP, intrinsic inhibitor of MMP, is regulated by signal transduction in response to genotoxins and is likely to be an important step in metastasis, angiogenesis and wound healing after ionizing radiation. Therefore, we studied radiation mediated TIMP expression and its mechanism in head and neck cancer cell lines. Materials and Methods : Human head and neck cancer cell lines established at Asan Medical Center were used and radiosensitivity $(D_0)$, radiation cytotoxicity and metastatic potential were measured by clonogenic assay, n assay and invasion assay, respectively. The conditioned medium was prepared at 24 hours and 48 hours after 2 Gy and 10 Gy irradiation and expression of TIMP protein was measured by Elisa assay with specific antibodies against human TIMP. hTIMP1 promoter region was cloned and TIMP1 luciferase reporter vector was constructed. The reporter vector was transfected to AMC-HN-1 and -HN-9 cells with or without expression vector Ras, then the cells were exposed to radiation or PMA, PKC activator. EMSA was peformed with oligonucleotide (-59/-53 element and SP1) of TIMP1 promoter. Results : $D_0$ of HN-1, -2, -3, -5 and -9 cell lines were 1.55 Gy, 1.8 Gy, 1.5 Gt, 1.55 Gy and 2.45 Gy respectively. n assay confirmed cell viability, over $94\%$ at 24hrs, 48hrs after 2 Gy irradiation and over 73% after 10 Gy irradiation. Elisa assay confirmed that cells secreted TIMP1, 2 proteins continuously. After 2 Gy irradiation, TIMP2 secretion was decreased at 24hrs in HN-1 and HN-9 cell lines but after 10 Gy irradiation, it was increased in all cell lines. At 48hrs after irradiation, it was increased in HN-1 but decreased in HN-9 cells. But the change in TIMP secretion by RT was mild. The transcription of TIMP1 gene in HN-1 was induced by PMA but in HN-9 cell lines, it was suppressed. Wild type Ras induced the TIMP-1 transcription by 20 fold and 4 fold in HN-1 and HN-9 respectively. The binding activity to -59/-53, AP1 motif was increased by RT, but not to SP1 motif in both cell lines. Conclusions : We observed the difference of expression and activity of TIMPs between radiosensitive and radioresistant cell line and the different signal transduction pathway between in these cell lines may contribute the different radiosensitivity. Further research to investigate the radiation response and its signal pathway of TIMPs is needed.

• Microbiology and Biotechnology Letters
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• v.36 no.1
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• pp.61-66
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• 2008

The proteins in whey are separated and used as food additives. The remains (mainly lactose) are spray-dried to produce sweet whey powder, which is widely used as an additive for animal feed. Sweet whey powder is also used as a carbon source for the production of valuable products such as polysaccharides. Glucose, fructose, galactose, and sucrose as asupplemental carbon source were evaluated for the production of PS-7 from Azotobacter indicus var. myxogenes L3 grown on whey based MSM media. Productions of PS-7 with 2% (w/v) fructose and sucrose were 2.05 and 2.31g/L, respectively. The highest production of PS-7 was 2.82g/L when 2% (w/v) glucose was used as the carbon source. Galactose showed low production of PS-7 among the carbon sources tested. The effects of various carbon sources addition to whey based MSM medium showed that glucose could be the best candidate for the enhancement of PS-7 production using whey based MSM medium. To evaluate the effect of glucose addition to whey based media on PS-7 production, fermentations with whey and glucose mixture (whey 1, 2, 3%; whey 1% + glucose 1%, whey 1% + glucose 2% and glucose 2%, w/v) were carried out. Significant enhancement of PS-7 production with addition of 1% (w/v) and 2% (w/v) glucose in 1% (w/v) whey media was observed. The PS-7 concentration of 2% glucose added whey lactose based medium was higher than that of 1% glucose addition, however, the product yield $Y_{p/s}$ was higher in 1% glucose added whey lactose based MSM medium. Therefore, the optimal condition for the PS-7 production from the Azotobacter indicus var.myxogenes L3, was 1% glucose addition to 1% whey lactose MSM medium.

• Magazine of the Korean Society of Agricultural Engineers
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• v.21 no.3
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• pp.104-120
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• 1979

I. Title of the Study Studies on the Development of Improved Subsurface Drainage Methods. -Drainage Performance of Various Subsurface Drain Materials- II. Object of the Study Studies were carried out to select the drain material having the highest performance of drainage; And to develop the water budget model which is necessary for the planning of the drainage project and the establishment of water management standards in the water-logged paddy field. III. Content and Scope of the Study 1. The experiment was carried out in the laboratory by using a sand tank model. The drainage performance of various drain materials was compared evaluated. 2. A water budget model was established. Various parameters necessary for the model were investigated by analyzing existing data and measured data from the experimental field. The adaptability of the model was evaluated by comparing the estimated values to the field data. IV. Results and Recommendations 1. A corrugated tube enveloped with gravel or mat showed the highest drainage performance among the eight materials submmitted for the experiment. 2. The drainage performance of the long cement tile(50 cm long) was higher than that of the short cement tile(25 cm long). 3. Rice bran was superior to gravel in its' drain performance. 4. No difference was shown between a grave envelope and a P.V.C. wool mat in their performance of drainage. Continues investigation is needed to clarify the envelope performance. 5. All the results described above were obtained from the laboratory tests. A field test is recommended to confirm the results obtained. 6. As a water balance model of a given soil profile, the soil moisture depletion D, could be represented as follows; $$D=\Sigma\limit_{t=1}^{n}(Et-R_{\ell}-I+W_d)..........(17)$$ 7. Among the various empirical formulae for potential evapotranspiration, Penman's formular was best fit to the data observed with the evaporation pans in Jinju area. High degree of positive correlation between Penman;s predicted data and observed data was confirmed. The regression equation was Y=1.4X-22.86, where Y represents evaporation rate from small pan, in mm/100 days, and X represents potential evapotranspiration rate estimated by Penman's formular. The coefficient of correlation was r=0.94.** 8. To estimate evapotranspiration in the field, the consumptive use coefficient, Kc, was introduced. Kc was defined by the function of the characteristics of the crop soil as follows; $Kc=Kco{\cdot}Ka+Ks..........(20)$ where, Kco, Ka ans Ks represents the crop coefficient, the soil moisture coefficient, and the correction coefficient, respectively. The value of Kco and Ka was obtained from the Fig.16 and the Fig.17, respectively. And, if $Kco{\cdot}Ka{\geq}1.0,$ then Ks=0, otherwise, Ks value was estimated by using the relation; $Ks=1-Kco{\cdot}Ka$. 9. Into type formular, $r_t=\frac{R_{24}}{24}(\frac{b}{\sqrt{t}+a})$, was the best fit one to estimate the probable rainfall intensity when daily rainfall and rainfall durations are given as input data, The coefficient a and b are shown on the Table 16. 10. Japanese type formular, $I_t=\frac{b}{\sqrt{t}+a}$, was the best fit one to estimate the probable rainfall intensity when the rainfall duration only was given. The coefficient a and b are shown on the Table 17. 11. Effective rainfall, Re, was estimated by using following relationships; Re=D, if $R-D\geq}0$, otherwise, Re=R. 12. The difference of rainfall amount from soil moisture depletion was considered as the amount of drainage required. In this case, when Wd=O, Equation 24 was used, otherwise two to three days of lag time was considered and correction was made by use of storage coefficient. 13. To evaluate the model, measured data and estimated data was compared, and relative error was computed. 5.5 percent The relative error was 5.5 percent. 14. By considering the water budget in Jinju area, it was shown that the evaporation amount was greater than the rainfall during period of October to March in next year. This was the behind reasonning that the improvement of surface drainage system is needed in Jinju area.

• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.513-520
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• 2006

A series of four in vitro experiments were conducted to evaluate condensed molasses solubles (CMS) as a source of nitrogen for ruminal microbes. In experiment 1, as compared with urea, the value of CMS as a nitrogen source was examined. In experiment 2, to determine the time needed for maximal response of microbial synthesis, the treatments were incubated for increasing times (from 6 h to 16 h). Because a sediment that was assumed to cause nitrogen loss was found after incubation in experiments 1 and 2, it was decided to avoid formation of sediment using sugar instead of molasses or a shorter time incubation (experiments 3 and 4). Furthermore, in experiment 4, because the extent to which ammonia nitrogen is released from CMS and urea before 6 h of incubation was uncertain, it was decided to examine the peaks of concentrations of ammonia nitrogen released from CMS and urea by sampling after 2 h incubation. There was no significant difference in the concentration of microbial-N between molasses/CMS and molasses/ urea treatments in experiment 1, although there were greater decreases in ammonia concentration with the molasses/CMS treatment. The microbial protein synthesis was increased progressively until 10 h for both treatments (experiment 2). Although ingredients that were completely soluble (sucrose, urea) were used in experiment 3, the sediment was still evident suggesting that the sediment was largely of microbial not feed origin. Ammonia release from CMS was much faster than from urea during 2 h incubation. In conclusion, the results of the present studies suggest that the feed value of CMS as a source of nitrogen for ruminal bacteria was similar to that of urea when it was estimated in vitro.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.175-186
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• 1985

Research situation and recent research activities of the RDA of Korea were reviewed and summarized for rice nurserybed. Sixty five percent of total 784 weed research items were carried out as rice research while only 6 percent was belonged to nurserybed within rice research. The floristic composition based on the degree of dominance significantly affected by herbicide properties, type of nurserybed and seeding itself. Herbicidal phytotoxicity of currently used several herbicides was greatly dependent upon the covering, absorption, germination, and irrigation regimes. The new safening agent "CGA 123 407" (4,6-dichloro-2-phenyl-pyrimidine) permited the safe application of pretilachlor (2-chloro-2',6-diethyl-N-(2-propoxyethyl) acetanilide) as a pre-emergence herbicide without reducing herbicidal efficacy. Several new herbicides, pyrazolate (4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yl-p-toluenesulphonate), SL-49 (1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-phenacyloxy-pyrazole) MY-93 (S(1-methyl-1-phenethyl)-piperidine-1-carbathioate) and DPX-84 ((methyl 2- ((4,6-dimethoxypyrimidin-2-yl) amino-carbonyl) aminosulfonylmethyl)) benzolate)) performed satisfactorily in terms of safety and herbicidal efficacy for both surface covered and surface pressed nurserybed after herbicide application and thus expected very significant contributions not only for all kind of nurserybeds but also for direct seeding.

• Journal of Gastric Cancer
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• v.6 no.3
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• pp.167-172
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• 2006

Purpose: The laparoscopy assisted gastrectomy has been increasingly reported as the treatment of choice for early gastric cancer. However, expert surgeons, who have performed a conventional open gastrectomy for a long time, tend to have a negative attitude toward laparoscopic procedures. The aim of this study was to determine the learning curve of a laparoscopy assisted distal gastrectomy (LADG) for a surgeon expert in performing an open gastrectomy and to analyze the factors that have an effect on a LADG. Materials and Methods: Between April 2005 and March 2006, 62 patients underwent a LADG with D1+beta lymph-node dissection. The 62 patients were divided into 10 sequential groups with 6 cases in each group (the last group was 8 cases), and the time required to reach the plateau of the learning curve was determined by examining the average operative times of these 10 groups. Other factors, such as sex, BMI, complications, transfusion requirements, the number of retrieved lymph nodes, and change of postoperative hemoglobin level, were also analyzed. Results: With the $5^{th}$ group (after 30 cases), the operative time reached a plateau (average: 170 min/operation). The differences between before the $30^{th}$ case and after the $31^{st}$ case with respect to changes in the postoperative hemoglobin level, the number of retrieved lymph nodes, the transfusion requirements, and the complications rate were not significant. Conclusion: According to an analysis of the operative time, experience with 30 LADGs in patients with early gastric cancer is the point at which the plateau of the learning curve (7 months) is reached. Abundant experience with a conventional open gastrectomy and a well-organized laparoscopic surgery team are important factors in overcoming the learning curie earlier.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.488-498
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• 2007

The purposes of this study were to: a) provide evidences concerning the effects of emotional leadership b) examine the impacts of emotional leadership on employee-related variables, 'job satisfaction', 'organizational commitment', 'organizational performance' and 'turnover intention', and c) identify a conceptual framework underlying emotional leadership. A survey was conducted from August 23 to November 3, 2005 to collect data from mid-level managers in food service company headquarters (N=219). Statistical analyses were completed using SPSS Win (12.0) for descriptive, reliability, factor and correlation analyses and AMOS (5.0) for confirmatory factor analysis and structural equation modeling. The main results of this study were as follows. First, the managers gave the highest point to their leaders in the emotional leadership competence 'organizational awareness : reading the currents, decision networks, and politics at the organizational level' and gave the lowest point in the emotional leadership competence 'influence: wielding effective tactics for persuasion'. Second, the means of job satisfaction was above the midpoint (3 points). Employees' job satisfaction with 'coworkers' was relatively high. However, the extents of satisfaction with 'payroll' 'promotion', and 'work environment' were relatively low. Third, the organizational commitment was above the midpoint (3 points). In the organizational commitment, 'loyalty' factor was higher than 'commitment' factor. Fourth, the means of organizational performance was above the midpoint. The highest organizational performance variable was 'internal efficiency; trying to reduce cost' and the lowest organizational performance variable was 'internal fairness ; equitable treatment and all are treated with respect with no regard to status and grade'. Fifth, most respondents intended on 'thinking of quitting ; towards turnover process'. Sixth, the test of hypothesis using structural equation modeling found that emotional leadership produced p[Isitive effects on job attitude and job performance. Emotional leadership enhanced job satisfaction and organizational commitment, and in turn, employees' attitude positive effects on organizational performance; emotional leadership also had a direct impact on organizational performance

• KOREAN JOURNAL OF CROP SCIENCE
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• v.40 no.6
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• pp.747-756
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• 1995

To find out the optimum application method of slow-releasing fertilizer(SRF) and conventional fertilizer(CF) with different fertilization rate under two culture methods[l0-day old seedling machine transplanting(MT) and direct-sowing on dry paddy(DS)] in the south-western region(clay loam soil) of Korea, used were Chosun slow-releasing fertilizer(silicate latex coated fertilizer: N-P$_2$O$_{5}$-K$_2$O =18-12-13) and conventional fertilizer. Plant height and number of tillers with different two culture methods were higher at MT than DS in early growth. The ratio of dry weight in heading stage was higher at CF than SRF in MT than DS and especially, SRF 80% + CF 20% than SRF 100% or CF 100%. Leaf area index (LAI) in heading stage was higher at CF in MT but higher at SRF in DS than their counterparts. Chlorophyll content was higher at SRF than in CF expect for heading stage(HS), especially in DS. It was highest at HS in CF without its difference during maximum tillering stage(MTS) and panicle formation stage(PFS), while highest at PFS in SRF with tendency of gradual increase and decrease before and after PFS, respectively. Heading was delayed 2~3 days at SRF in two cultrue methods and 4~5 days at SRF in DS in comparison with CF in MT with delay of 2 days at DS compared with MT. Culm length was longer at CF in MT and at SRF in DS than their counterparts. Panicle number per m was more at SRF and in DS. Filled grain ratio was higher at CF and in MT. Yield was obtained 101 and 100% at 100% and 80% level of SRF in DS respectively, and 96% at 80% level of CF in MT, compared with conventional application method (516kg /l0a), and increased 2~4% at DS and 0~3% at MT in SRF. Yield was high in order of 100%(SRF) =80%(SRF) + 20%(CF) > 100%(SRF) + 20%(CF) > 80%(SRF) at MT and 80%(SRF) + 20%(CF) =100%(SRF) > 80%(SRF) =100%(SRF) + 20%(CF) at DS.

• Journal of environmental and Sanitary engineering
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• v.15 no.4
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• pp.59-77
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• 2000

This study was carried out to investigate on several factors, which contaminative the water quality through the water pipe during feeding water, in 42 largescaled apart-ments(total 84 cases) and assayed the Volatile Organic Compounds(VOCs) and concen-tration of heavy metals that inflow and outflow in reservior water in Jeonnam area(Mokpo, Suncheon, Yeosu) from January 1999 to December 1999. The results obtained were summarized as follows ; 1. The quality of the water pipe composition in the order of frequency in the quality of water pipes were Copper(45.2%)> Zinc(38.9%)> Stainless steel(9.5%)> PVC(4.8%)> PM(2.4%) in observing 42 sites. All of the drain pipes were used the cast iron quality. 2. The result of certification curve from 12 items(17kind) of VOCs was $1.0-4.0{\mu{g}}/{\ell}$ range, a coefficient of correlation was shown 0.99 over. A MDL of each substance range was within $0.1-1.0{\mu{g}}/{\ell}$. 3. The result of the assay, 5 kinds(Viny chloride, Dichloromethane, Ethylbenzene, M,P-xylene, Styrene) of the VOCs of 14 kinds was not detected and the other items were detected slightly. The detection rate of one item and over in total VOCs samples, were 25.9% in inflow and 27.9% in outflow. And frequency of detect in inflow/outflow of THM(Chloroform, Bromodichloro-methane, Dibromochloromethane, Bromoform) were shown higher than 94.1%, 97.0% each stages. It comes to the conclusion that all of the samples were reason able for drinking water standards. 4. The coefficient of correlation were reasonable, it shown 0.999 over in $0.1-1.0{\mu{g}}/{\ell}$ of a measuring range conditions of 4kinds in organic substance(Zn, Cu, Fe, Mn). 5. The results were showed suitability in 78 cases(92.9%) and unsuitability in 6 cases (7.1%), in 84 cases of in organic substances. Compare to inflow stage, mean concentrations of heavy metal, were increased slightly in Zn, Cu, Fe except Mn than outflow stage. The result of the mean concentration in organic substance inflow and outflow in the apartment water tank using Pair-compared T-test, in 95% reliance index, were $0.179mg/{\ell}(0.151-0.307mg/{\ell})$ in Zinc, $0.136mg/{\ell}(0.113-0.230mg/{\ell})$ in Copper, $0.052mg/{\ell}(0.048-0.098mg/{\ell})$ in Fe, and there was a bit growing tendency but there was no differece in Mn. 6. The mean concentration of Copper which used Cu pipe as a water supply pipe in apartment were $0.216mg/{\ell}(0.161-0.338mg/{\ell})$ in case of the Zine pipe were $0.286mg/{\ell}(0.204-0.435mg/{\ell})$. It shows that the detection rate was more higher than the other material used in Cu or Zn as the water supply pipe. We supposed to Cu and Zn substance were gushing out water supply pipe.