• Applied Chemistry for Engineering
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• v.35 no.4
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• pp.321-328
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• 2024

The performance of carbon fluoride-based lithium primary batteries (Li/CF_X) is limited due to poor rate capability resulting from the low conductivity of carbon fluoride, which is used as the active material. Therefore, in this study, we applied a carbon coating using pyrolysis fuel oil on carbon fluoride to overcome this limitation and considered its electrochemical performance. An amorphous carbon layer was formed on the surface of the carbon fluoride through carbon coating, and the surface physicochemical properties of the carbon fluoride were meticulously considered based on the heat treatment temperature. The advanced research chemical 1000 heat treated at 450 ℃ (ARC@C450) sample, which was commercial carbon fluoride heat-treated at 450 ℃, showed the largest increase in the concentration of sp² carbon bonds (62%) and the highest formation of semi-ionic C-F bonds. Also, the primary battery using the ARC@C450 sample as a cathode active material exhibited stable discharge capability at the highest rate of 5 C (392 mAh/g), and the R_ct value was reduced by 53% compared to the untreated sample. Therefore, we proposed pyrolysis fuel oil-based carbon coating as a method to overcome the low conductivity of carbon fluoride, and the carbon-coated carbon fluoride showed excellent rate performance, suggesting its potential application in high-power primary batteries.

• Korean Circulation Journal
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• v.52 no.8
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• pp.606-620
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• 2022

Background and Objectives: Protein-losing enteropathy (PLE) is a devastating complication after the Fontan operation. This study aimed to investigate the clinical characteristics, treatment response, and outcomes of Fontan-associated PLE. Methods: We reviewed the medical records of 38 patients with Fontan-associated PLE from 1992 to 2018 in 2 institutions in Korea. Results: PLE occurred in 4.6% of the total 832 patients after the Fontan operation. After a mean period of 7.7 years after Fontan operation, PLE was diagnosed at a mean age of 11.6 years. The mean follow-up period was 8.9 years. The survival rates were 81.6% at 5 years and 76.5% at 10 years. In the multivariate analysis, New York Heart Association Functional classification III or IV (p=0.002), low aortic oxygen saturation (<90%) (p=0.003), and ventricular dysfunction (p=0.032) at the time of PLE diagnosis were found as predictors of mortality. PLE was resolved in 10 of the 38 patients after treatment. Among medical managements, an initial heparin response was associated with survival (p=0.043). Heparin treatment resulted in resolution in 4 patients. We found no evidence on pulmonary vasodilator therapy alone. PLE was also resolved after surgical Fontan fenestration (2/6), aortopulmonary collateral ligation (1/1), and transplantation (1/1). Conclusions: The survival rate of patients with Fontan-associated PLE has improved with the advancement of conservative care. Although there is no definitive method, some treatments led to the resolution of PLE in one-fourth of the patients. Further investigations are needed to develop the best prevention and therapeutic strategies for PLE.

• Journal of Preventive Medicine and Public Health
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• v.23 no.3 s.31
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• pp.324-337
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• 1990

To assess the effectiveness of the interventions in working environment and personal hygiene for the occupational exposure to the lead, 156 workers (116 exposed subjects and 40 controls) of a newly established battery factory were examined for their blood lead concentration (Pb-B) in every 3 months up to 18 months. Air lead concentration (Pb-A) of the workplaces was also checked for 3 times in 6 months interval from August 1987. Environmental intervention included the local exhaust ventilation and vacuum cleaning of the floor. Intervention of the personal hygiene included the daily change of clothes, compulsory shower after work and hand washing before meal, prohibition of cigarette smoking and food consumption at the work site and wearing mask. Mean Pb-B of the controls was $21.97{\pm}3.36{\mu}g/dl$ at the preemployment examination and slightly increased to $22.75{\pm}3.38{\mu}g/dl$ after 6 months. Mean Pb-B of the workers who were employed before the factory was in operation (Group A) was $20.49{\pm}3.84{\mu}g/dl$ on employment and it was increased to $23.90{\pm}5.30{\mu}g/dl$ after 3 months (p<0.01). Pb-B was increased to $28.84{\pm}5.76{\mu}g/dl$ 6 months after the employment which was 1 month after the initiation of intervention program. It did not increase thereafter and ranged between $26.83{\mu}g/dl\;and\;28.28{\mu}g/dl$ in the subsequent 4 tests. Mean Pb-B of the workers who were employed after the factory had been in operation but before the intervention program was initiated (Group B) was $16.58{\pm}4/53{\mu}g/dl$ before the exposure and it was increased to $28.82{\pm}5.66{\mu}g/dl$(P<0.01) in 3 months later (1 month after the intervention). The values of subsequent 4 tests remained between 26.46 and $28.54{\mu}g/dl$. Mean Pb-B of the workers who were employed after intervention program had been started (Group C) was $19.45{\pm}3.44{\mu}g/dl$ at the preemployment examination and gradually increased to $22.70{\pm}4.55{\mu}g/dl$ after 3 months(P<0.01), $23.68{\pm}4.18{\mu}g/dl$ after 6 months, and $24.42{\pm}3.60{\mu}g/dl$ after 9 months. Work stations were classified into 4 parts according to Pb-A. The Pb-A of part I, the highest areas, were $0.365mg/m^3$, and after the intervention the levels were decreased to $0.216mg/m^3\;and\;0.208mg/m^3$ in follow-up tests. The Pb-A of part II was decreased from $0.232mg/m^3\;to\;0.148mg/m^3,\;and\;0.120mg/m^3$ after the intervention. Pb-A of part III and W was tested only after intervention and the Pb-A of part III were $0.124mg/m^3$ in Jannuary 1988 and $0.081mg/m^3$ in August 1988. The Pb-A of part IV not stationed at one place but moving around, was $0.110mg/m^3$ in August 1988. There was no consistent relationship between Pb-B and Pb-A. Pb-B of the group A and B workers in the part of the highest Pb-A were lower than those of the workers in the parts of lower Pb-A. Pb-B of the workers in the part of the lowest Pb-A incerased more rapidly. Pb-B of group C workers was the highest in part I and the lowest in part IV. These findings suggest that Pb-B is more valid method than Pb-A for monitoring the health of lead workers and intervention in personal hygiene is more effective than environmental intervention.

• Korean Journal of Medicinal Crop Science
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• v.9 no.2
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• pp.116-123
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• 2001

This study was carried out to investigate antioxidative, antimicrobial activity and the effect on hepatotoxicity in various extracts of Artemisia iwayomogi. The herb has been used widely for jaundice, hepatitis and liver cirrhosis in chinese medicine. Solid yield by various extraction solvents, 18.1%, was the highest in water extract. To find antioxidative activity in Artemisia iwayomogi was estimated radical scavenging effect by DPPH method in various extracts and change of the POV(peroxide value) of various extracts added in soybean oil during 20 days at $60^{\circ}C$. Radical scavenging effect by DPPH method was the most effective in methanol extract. Added 1,000ppm water extract and methanol extract in soybean oil, the POV of them, 46.8(meq/kg) and 50.8(meq/kg) were lower than that of control, 79.1(meq/kg), during 20 days storage. After antimicrobial activity of various extracts of Artemisia iwayomogi on bacteria was carried out by paper disc method, it found that the ethanol extract was the strongest activity on Vibrio parahaemolyticus. In vivo experiment was to investigate the effect of Artemisia iwayomogi water extract(AIWE) on hepatotoxicity by carbon tetrachloride$(CCl_4)$ in rats. The experiment groups were divided into five groups for recovery(for 3 days) and three groups for protection(for 10 days) in rat liver. The weights and morphological changes of liver and the body weight were examined in each groups. Compared with $CCl_4$ treatment groups$(CCl_4\;only)$, liver and liver/body(%) weights of AIWE pretreatment groups for 3 days and AIWE posttreatment groups for 10 days were declined. In macrography, fibrious exudates and swelling of liver were decreased in AIWE treatment groups. Accumulation of lipid droplets and necrosis of hepatocytes were also decreased in AIWE treatment groups in microscopically. In these results, AIWE seems to enhance hepato-protective and recoverable effect on $CCl_4$ induced hepatotoxicity in rats.

• Journal of Intelligence and Information Systems
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• v.25 no.2
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• pp.141-166
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• 2019

Recently, channels like social media and SNS create enormous amount of data. In all kinds of data, portions of unstructured data which represented as text data has increased geometrically. But there are some difficulties to check all text data, so it is important to access those data rapidly and grasp key points of text. Due to needs of efficient understanding, many studies about text summarization for handling and using tremendous amounts of text data have been proposed. Especially, a lot of summarization methods using machine learning and artificial intelligence algorithms have been proposed lately to generate summary objectively and effectively which called "automatic summarization". However almost text summarization methods proposed up to date construct summary focused on frequency of contents in original documents. Those summaries have a limitation for contain small-weight subjects that mentioned less in original text. If summaries include contents with only major subject, bias occurs and it causes loss of information so that it is hard to ascertain every subject documents have. To avoid those bias, it is possible to summarize in point of balance between topics document have so all subject in document can be ascertained, but still unbalance of distribution between those subjects remains. To retain balance of subjects in summary, it is necessary to consider proportion of every subject documents originally have and also allocate the portion of subjects equally so that even sentences of minor subjects can be included in summary sufficiently. In this study, we propose "subject-balanced" text summarization method that procure balance between all subjects and minimize omission of low-frequency subjects. For subject-balanced summary, we use two concept of summary evaluation metrics "completeness" and "succinctness". Completeness is the feature that summary should include contents of original documents fully and succinctness means summary has minimum duplication with contents in itself. Proposed method has 3-phases for summarization. First phase is constructing subject term dictionaries. Topic modeling is used for calculating topic-term weight which indicates degrees that each terms are related to each topic. From derived weight, it is possible to figure out highly related terms for every topic and subjects of documents can be found from various topic composed similar meaning terms. And then, few terms are selected which represent subject well. In this method, it is called "seed terms". However, those terms are too small to explain each subject enough, so sufficient similar terms with seed terms are needed for well-constructed subject dictionary. Word2Vec is used for word expansion, finds similar terms with seed terms. Word vectors are created after Word2Vec modeling, and from those vectors, similarity between all terms can be derived by using cosine-similarity. Higher cosine similarity between two terms calculated, higher relationship between two terms defined. So terms that have high similarity values with seed terms for each subjects are selected and filtering those expanded terms subject dictionary is finally constructed. Next phase is allocating subjects to every sentences which original documents have. To grasp contents of all sentences first, frequency analysis is conducted with specific terms that subject dictionaries compose. TF-IDF weight of each subjects are calculated after frequency analysis, and it is possible to figure out how much sentences are explaining about each subjects. However, TF-IDF weight has limitation that the weight can be increased infinitely, so by normalizing TF-IDF weights for every subject sentences have, all values are changed to 0 to 1 values. Then allocating subject for every sentences with maximum TF-IDF weight between all subjects, sentence group are constructed for each subjects finally. Last phase is summary generation parts. Sen2Vec is used to figure out similarity between subject-sentences, and similarity matrix can be formed. By repetitive sentences selecting, it is possible to generate summary that include contents of original documents fully and minimize duplication in summary itself. For evaluation of proposed method, 50,000 reviews of TripAdvisor are used for constructing subject dictionaries and 23,087 reviews are used for generating summary. Also comparison between proposed method summary and frequency-based summary is performed and as a result, it is verified that summary from proposed method can retain balance of all subject more which documents originally have.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.100-106
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• 2001

Purpose : We performed a retrospective analysis to compare short term results of induction chemotherapy-radiotherapy versus concurrent chemo-radiotherapy in patients with locally advanced nasopharyngeal carcinoma. Materials and Methods : From Oct. 1989 to May 1998, 62 patients with locally advanced nasopharyngeal carcinoma were treated with induction chemotherapy followed by radiotherapy (induction group) or concurrent chemo-radiotherapy (concurrent group). Induction chemotherapy was done for 50 patients, and concurrent chemotherapy for 12 patients. Age, sex, performance status, and pathologic types were evenly distributed between two groups. Stage distribution showed $32\%$ with IIB, $32\%$ with III, and $38\%$ with IV in induction group, and $50\%,\;33.3\%,\;and\;16.7\%$ in concurrent group, respectively. Chemotherapy regimen was CF (cisplatin and 5-FU) in both groups, and drug delivery method also same. Cisplatin $100\;mg/m^2$ was intravenously infused on day 1, and 5-FU $1,000\;mg/m^2$ on day $2\~6$. This was repeated at 3 weeks interval. At the end of radiotherapy, total cycles of chemotherapy were $1\~3$ (median 2) in both groups. Conventionally fractionated radiotherapy with daily fraction size $1.8\~2.0\;Gy$ and 5 fractions/week was done. Total dose was $69.4\~86\;Gy$(median 73.4 Gy) for induction group, and $69.4\~75.4\;Gy$ (median 70.8 Gy) for concurrent group. Follow-up time was $9\~116$ months (median 40.5 months) for induction group, $14\~29$ months (median 21 months) for concurrent group, respectively. Results : Overall 2 year survival rate (2YSR) for all patients was $78.7\%$. According to treatment modality, 2YSR were $77\%$ for induction group, $87\%$ for concurrent group (p>0.05). 2 year disease-free survival rate were $56\%$ and $81\%\;(p>0.05)$, respectively. Complete response to treatment were $75.5\%$ for induction group and $91.7\%$ for concurrent group, but there was no statistical difference. The incidence of grade $3\~4$ hematologic toxicity during radiotherapy was not differ between two groups, but grade 2 leukopenia was more frequent in concurrent group $(18\%\;vs\;66.7\%)$Grade $3\~4$ mucositis was more frequent in concurrent group $(4.0\%\;vs\;33.3\%)$. Overall incidence of grade $3\~4$ acute toxicity during radiotherapy was more frequent in concurrent group $(6.0\%\;vs\;41.7\%,\;p=0.005)$. Conclusion : Concurrent chemo-radiotherapy showed a trend of improvement in short-term survival and in treatment response when compared with induction chemotherapy-radiotherapy in locally advanced nasopharyngeal carcinoma. More controlled randomized trial are needed.

• Radiation Oncology Journal
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• v.15 no.2
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• pp.79-95
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• 1997

Purpose : Phospholipase C(PLC) isozymes play significant roles in signal transduction mechanism. $PLC-\gamma$ 1 is one of the key regulatory enzymes in signal transduction for cellular proliferation and differentiation. Ras oncoprotein, EGFR, and PKC are also known to be involved in cell growth. The exact mechanisms of these signal transduction following irradiation, however, were not clearly documented Thus, this study was Planned to determine the biological significance of PLC, ras oncoprotein, EGFR, and PKC in damage and regeneration of rat intestinal mucosa following irradiation. Material and Method : Sixty Sprague-Dawley rats were irradiated to entire body with a single dose of 8Gy. The rats were divided into S groups according to the sacrifice days after irradiation. The expression of PLC, ras oncoprotein, EGFR and PKC in each group were examined by the immunoblotting and immunohistochemistry. The histopathologic findings were observed using H&I stain, and the mitoses for the evidence of regeneration were counted using the light microscopy & PCNA kit. The Phosphoinositide(PI) hydrolyzing activity assay was also done for the indirect evaluation of $PLC-\gamma$ 1 activity. Results: In the immunohistochemistry , the expression of $PLC-{\beta}$ was negative for all grøups. The expression of $PLC-{\gamma}1$ was highest in the group III followed by group II in the proliferative zone of mucosa. The expression of $PKC-{\delta}1$ was strongly positive in group 1 followed by group II in the damaged surface epithelium. The above findings were also confirttled in the immunoblotting study. In the immunoblotting study, the expressions of $PLC-{\beta}$, $PLC-{\gamma}1$, and $PKC-{\delta}1$ were the same as the results of immunohis-tochemistry. The expression of ras oncoprctein was weakly positive in groups II, III and IV. The of EGFR was the highest in the group II, III, follwed by group IV and the expression of PKC was weakly positive in the group II and III. Conclusion: $PLC-{\gamma}1$ mediated signal transduction including ras oncoprotein, EGFR, and PKC play a significant role in mucosal regeneration after irradiation. $PLC-{\delta}1$ mediated signal transduction might have an important role in mucosal damage after irradiation. Further studies will be necessary to confirm the signal transduction mediating the $PKC-{\delta}1$.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.379-385
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• 1997

Purpose : Ovarian dysgerminoma is a highly radiosensitive malignant tumor occurring in young age group. The conventional treatment was total abdominal hysterectomy and bilateral salpingo-oophorectomy followed by radiotherapy. We retrospectively analyzed the treatment results of Patients who had received radiotherapy in the era before chemotherapy was widely used. Material and Method : Twenty two patients with ovarian dysgerminoma were treated at the Department of Therapeutic Radiology, Seoul National University Hospital between August, 1980 and May, 1991. Four patients were excluded from this study, because three patients received incomplete treatment and one received combined chemotherapy. Sixteen patients received postoperative radiotherapy and two patients had radical radiotherapy as tumor was unresectable. Median follow-up period was 99 months (range, 51-178) Median age was 22 years (range, 11-42). Among the postoperatively treated patients, three Patients were in stage IA, eight in stage IC, two in stage II, and three in stage III. One patient had Turner's syndrome. Radiotherapy was performed with high energy photon (telecobalt unit or linear accelerator, either 6MV or 10MV), The radiation dose to the whole abdomen was 1950-2100cGy (median, 2000) and 1050-2520cGy was added to the whole pelvis, the total dose to the whole pelvis was 3000-4500cGy (median, 3500). Prophylactic Paraaortic area irradiation was done in six Patients (dose range, 900-1500cGy). One patient who had positive Paraaortic node, received radiation dose of 1620cGy, followed by additional 900cGy to the gross mass with shrinking field. Total dose to the paraaortic node was 4470cGy. Six patients, including one who had paraaortic node metastasis, received Prophylactic irradiation to mediastinum and supraclavicular area (2520cGy). Of the two patients with unresectable tumors who received radical radiotherapy, one was in stage III and the other was in stage IV with left supraclavicular lymph node metastasis. The stage III patient received radiation to the whole abdomen (2000cGy), followed by boost to whole pelvis (2070cGy) and paraaortic area (2450cGy). Stage IV patient received radiation to the whole abdomen (2000cGy), followed by radiation to the whole pelvis and paraaortic area (2400cGy), mediastinum (2520cGy) , and left supraclavicular area (3550cGy) .Results : The 5 year local control rate was $100\%$ in patients who received postoperative adiuvant radiotherapy after total abdominal hysterectomy and bilateral salpingo-oophorectomy. Only one patient in stage III who did not receive prophylactic irradiation to mediastinum developed mediastinal metastasis. but was salvaged by chemotherapy. So. the 5 year overall survival rate uras also $100\%$. Two patients who received radiation only, are alive without disease at 112 and 155 months. Conclusion : Postoperntive adjuvant radiotherapy as well as radical radiotherapy in unresectable ovarian dysgerminoma was very effective. aut chemotherapy is also an effective treatment modality We now recomrneifd chemotherapy for Patients who need to save their ovarian functien and reserve radiotherapv fov chemo-resistant tumor or recurrence alter che motherapy.

• Korean Journal of Digital Imaging in Medicine
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• v.9 no.1
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• pp.37-43
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• 2007

1. Purpose : This study is to present effective exposure conditions to acquire the best image of simple abdomen in Film Screen (F.S) system and Computed Radiography (C.R) system. 2. Method : In the F.S system, while an exposure condition was fixed as 70kVp, images of a patients simple abdomen were taken under the different mAs exposure conditions. Among these images, the best one was chosen by radiologists and radiological technologists. In the C.R system, the best image of the same patient was acquired with the same method from the F.S system. Both characteristic curves from F.S system and C.R system were analyzed. 3. Results : In the F.S system, the best exposure condition of simple abdomen was 70kVp and 20mAs. In the CR system, with the fixed condition at 70kVp, the image densities of human organs, such as liver, kidney, spleen, psoas muscle, lumbar spine body and iliac crest, were almost same despite different environments (3.2mAs, 8mAs, 12mAs, 16mAs and 20mAs). However, when the exposure conditions were over or under (below) 12mAs, the images between the abdominal wall and the directly exposed part became blurred because the gap of density was decreased. In the C.R system, while the volume of mAs was decreased, an artifact of quantum mottle was increased. 4. Conclusion : This study shows that the exposure condition in the C.R system can be reduced 40% than in the F.S system. This paper concluded that when the exposure conditions are set in CR environment, after the analysis of equipment character, such as image processing system(EDR : Exposure Data Recognition processing), PACS and so on, the high quality of image with maximum information can be acquired with a minimum exposure dose.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.2
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• pp.100-105
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• 1985

To find out the optimum level of nitrogen fertilization and better distribution of application time for seed production of Festuca arundianacea S. (var. Alta), this filed experiment was performed at Livestock Experiment Station in Suweon, during 1979 to 1981. The treatments used in this study were three nitrogen fertilizing levels (120, 180 and 240kg/ha) and four different methods of nitrogen distribution (i. single application of whole amount in early Spring, ii. 50 percent each in Autumn and early Spring, iii. 50 percent each in early Spring and at begin of heading stage and iv. 50 percent in Autumn and 25 percent in early Spring and at begin of heading stage respectively). The experiment was arranged as a split-plot design with 4 replications and performed at the experimental field of the Livestock Experiment Station in Suweon, during 1979 to 1981. The results obtained are summarized as follows: 1. Date of heading stage of Festuca arundinacea was about May 21 and that of flowering stage was June 1 to 3. The optimum stage for the seed harvesting of Festuca arundinacea (var. Alta) was June 25 about 22 to 23 days after full flowering stage. Average plant height was about 127cm and the panicle length, 24cm. 2. 1000 grain weight was 2.72g and the number of panicles were 85 to 107 per square meter. 3. The mean seed wield for two years was 678.8kg/ha with the average of whole treatments and 781.9kg/ha with the best treatment (50 percent in Autumn and 25 percent in early Spring and at begin of heading stage with 240kg/ha respectively). 4. The average germination rate of harvesting seeds was 87.0 percent and it was increasing trend according to frequent application of fertilizer. 5. The average DM yield of aftermath seed harvesting was 6155kg/ha with two cut, and it was the largest DM yield from the higher nitrogen level and also from the single application in early Spring.