• Journal of Korean Society of Environmental Engineers
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• v.37 no.12
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• pp.696-704
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• 2015

This study was carried out to evaluate the optimum operational condition of Semi-continuously Fed and Mixed Reactor (SCFMR) to treat the dairy cow manure and saw dust mixture. Step-wise increase in organic loading rates (OLRs) or decrease in hydraulic retention times (HRTs) were utilized until the biogas volume became significantly decreased at mesophilic temperature ($35^{\circ}C$). The optimum operating condition of the SCFMR fed with TS 13% dairy cow manure and saw dust mixture was found to be an HRTs of 25 days and its corresponding OLRs of $4.45kg\;VS/m^3-day$. At this condition the biogas and methane production rates were 1.44 v/v-d and 1.12 v/v-d (volume of biogas per volume of reactor per day), respectively and the TVS removal efficiency of 37% was achieved. The successful operation with such a high OLR was due to the high reactor alkalinity concentration of 14,500~15,600 mg/L as $CaCO_3$ as a result of the characteristic of the original substrate, dairy cow manure and saw dust mixture whose alkalinity was more than 8,000 mg/L as $CaCO_3$. The parameters for the reactor stability, the ratios of volatile acids and alkalinity concentrations (V/A) and the ratio of propionic acid and acetic acid concentrations (P/A) appeared to be 0.11 and 0.43, respectively, that were greatly stable in operation. Free ammonia toxicity was not experienced due to the long term acclimation by the reactor TS content ranged 7.2~10.4% during the entire operational period.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.9
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• pp.636-642
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• 2013

In order to overcome drawbacks (i.e., filtration and recovery) of conventional powder type photocatalysts, nano-ZnO/Laponite/PVA (ZLP) photocatalyzed adsorption balls were developed by using in situ mixing of nanoscale ZnO as a photocatalyst, and Laponite as both adsorbent and supporting media in deionized water, followed by the poly vinyl alcohol polymerization with boric acid. The optimum mixing ratio of nano-ZnO:Laponite:PVA:deionized water was found to be 3:1:1:16 (by weight), and the mesh and film produced by PVA polymerization with boric acid might inhibit both swelling of Laponite and detachment of nanoscale ZnO from ZLP balls. Drying ZLP balls with microwave (600 watt) was found to produce ZLP balls with stable structure in water, and various sizes (55~500 ${\mu}m$) of pore were found to be distributed based on SEM and TEM results. In the initial period of reaction (i. e., 40 min), adsorption through ionic interaction between methylene blue and Laponite was the main removal mechanism. After the saturation of methylene blue to available adsorption sites for Laponite, the photocatalytic degradation of methylene blue occurred. The effective removal of methylene blue was attributed to adsorption and photocatalytic degradation. Based on the results from this study, synthesized ZLP photocatalyzed adsorption balls were expected to remove recalcitrant organic compounds effectively through both adsorption and photocatalytic degradation, and the risks of environmental receptors caused by detachment of nanoscale photocatalysts can be reduced.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.2
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• pp.87-98
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• 2016

During the period between July 3 and 27 of 2009, water samples were collected from the Russian coast at a depth of 30m from 26 stations (including Ulleung and Japan basins) onboard the Russian survey vessel R/V Lavrentyev following 4 lines (D, R, E, and A). The samples were analyzed for nutrients and chlorophyll a contents. All parameters exhibited higher values in warm waters than in cold waters ($NH_4:1.8-fold$, $PO_4:1.8-fold$, $SiO_2:1.2-fold$, and chlorophyll-${\alpha}$:1.9-fold), except nitrates, which was 1.4-fold higher in cold waters than in warm waters. The horizontal distribution of ammonia, phosphate, and chlorophyll-${\alpha}$ was very similar to each other and showed the highest values in the waters near Russia, where a upwelling influence of cold current and bottom water prevails, while relatively low distribution was observed at the Ulleung Basin. On the other hand, nitrates showed the highest concentration at the Ulleung Basin, which is under the direct influence of the Tsushima warm water, and showed a gradual decrease northward. The N/P ratio showed the highest value in the Tsushima middle water, rather than in the North Korean Cold Water, the Tsushima Warm Water was the primary source of nitrate flow into the East Sea. However, the average concentration of phosphate in the warm waters was < $0.2{\mu}M$, thereby limiting phytoplankton growth, while a high concentration of phosphate in cold waters showed a direct correlation with chlorophyll-${\alpha}$. The results of principal component analysis for the identification of primary factors that influence the marine environment showed that principal component I was water temperature and principal component II was influenced chlorophyll-${\alpha}$ and nutrients. Therefore, Study area has greatest influenced by water temperature, and clearly distinct cold and warm water regions were observed in the East Sea.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.565-572
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• 2005

An experiment was conducted to determine the effect of supplementation of insoluble dietary fiber (Vitacel®) on growth performance and nutrient digestibility in weanling pigs. A total of 96 pigs that averaged 6.49$\pm$0.52kg BW and 23$\pm$2.1d age were allocated in a randomized block design with two pigs per pen and 12 pens per treatment. Pigs and feeders were weighed 10-days interval for the 40-d trials to determine ADG, ADFI and feed:gain ratio(F:G). Pigs were fed one of four diets:1) Control diet (C) 2) C+0.3% insoluble dietary fiber(IDF) 3) C+0.6% IDF and 4) c+0.9% IDF. For the determination of fecal nutrients digestibility, pigs were fed diets(diet 2) with 1% Celite-545(Fluka) as a marker and feces were collected on $9^{th}$ day and $18^{th}$ day after feeding diet 2. During the whole experimental period, pigs fed diet with 0.3% IDF have significantly higher ADG than other dietary treatment groups(P<0.05). ADG of pigs fed diet with 0.6% IDF was higher than that of pigs fed control diet(P<0.05). However, there was no significant difference in ADG between control group and 0.9% IDF group(P>0.05). ADFI of pigs fed diet with 0.3% IDF was significantly higher than any other dietary treatment groups(P<0.05). There was no significant difference in ADFI among control group, 0.6% and 0.9% IDF supplementation groups (P>0.05). Digestibilities of organic matter, crude protein, crude fiber and energy were significantly higher in 0.3% IDF supplementation group than any other dietary groups. However, there was no difference in over all nutrient digestibilities between 0.6% and 0.9% IDF group. Feeding diets more than 0.6% IDF did not affect the rest of the nutrients digestibilities except for ADF digestibility compared to control diet. Dietary supplementation level of IDF showed a significant quadratic effect on performance improvement of piglets. This response of growth performance to IDF supplementation is, as expected, in agreement with that of nutrient digestibility. Our results showed that IDF supplementation to diet for weaned piglets might be beneficial in terms of growth and nutrient digestibility. However, there should be more study on the relationship between level of IDF supplementation and piglet response as well as the exact mode of action of IDF in weaned piglets.

• Journal of Animal Science and Technology
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• v.45 no.3
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• pp.369-376
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• 2003

This experiment was conducted to investigate the influence of different levels of metabolizable energy (ME) and crude protein (CP) on post-molt performance and egg quality of spent laying hens. Four hundred and thirty two, ISA Brown hens at sixty six weeks of age after molt induction were fed six experimental diets containing three ME (2,750, 2,800, 2,850 kcal/kg) with two CP (15, 17%) levels in a factorial design. The influence of ME and CP were evaluated on egg production, egg weight and feed intake throughout 24 weeks of production. Egg mass and feed conversion ratio (FCR) were measured during the experimental period. Haugh unit, yolk color and eggshell breaking strength were measured at 5%, 50%, peak, post peak and end stage of egg production. The hens fed 2800 kcal/kg diet along with 15% CP recorded the highest outcome of egg production (P<0.05). The egg weight has been shown to increase with hens receiving 2,800 kcal/kg ME. Daily egg mass tended to increase in hens fed with 15% CP and 2,800 kcal/kg ME. Feed intake decreased significantly with the level of ME and CP in the diet increased (P<0.05). Yolk color was improved significantly in eggs laid by the hens receiving 17% CP than 15% diet. It also tended to be higher in 17% CP with 2,800 or 2,850 kcal/kg ME diet treatments. Egg shell breaking strength increased with hens receiving diets of 15% CP and 2,800 kcal/kg. From this experiment it can be concluded that the ME level of 2,800 kcal/kg coupled with 15% CP could be used to achieve the higher egg production and better eggshell strength in induced molting hens.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.2
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• pp.59-67
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• 2017

The aim of this experiment was to investigate the effect of air suction rate (SR) during the composting process of swine manure mixed with sawdust used as a bulking agent. In the 25 L composting reactors, the suction rate (SR) was at four different treatment levels (100%, 200%, 300%, 400%), and were fixed on the based on constant aeration rate into the composting mixtures. The temperature reached to thermophilic phase within 2 days and it was maintained up to the $5^{th}$ day of the composting process in all reactors and then gradually decreased to room temperature at the end of the composting process. The moisture content (MC, %) of the initial mixtures was 64.27%, and it was reduced to 38.4, 33.08, 14.59 and 11.93 in the different suction rate of 100%, 200%, 300%, 400%, respectively in the end process. During the composting, the level of pH was increased from 6.83 to 8.67 and it gradually decreased to 7.56 in 100% and 200%(SR). At the same time, the pH values were reduced only up to 8.19 at 300%, and 8.08 at 400%(SR), showing that suction strengths of 100% and 200% were the better option for composting than those of 300% and 400%. The total Kjeldahl nitrogen (TKN) of initial composts mixtures was 2.3% and were changed in 3.3, 3.1, 2.5, and 2.3% at the end of the composting period from the 100%-400% (SR) variations respectively. These results also indicated that 100% and 200% (SR) were more affected by the dry mass loss as $CO_2$ and water evaporation. The initial value of C/N ratio was 25.17 and were significantly reduced to 11.88, 11.97, 14.31, and 14.72 at the end of the experiment, respectively from the 100%-400% (SR) variations. These results suggest that the suction rate (SR) of 100% and 200% relative to constant air supply would be the optimal conditions to produce high-quality compost.

• The Journal of Korean Physical Therapy
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• v.14 no.3
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• pp.238-272
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• 2002

This study was intended to find out the factors affecting to the IADL, allowing objective assessment of physical function status of increasing elderly populations. The subjects of 635 elderly persons aged over 65 years old who live in Taejon metropolitan city were interviewed during the two-month period from June to July of 2000. The IADL of Older American Resources and Services(OARS), developed in Duke medical college of USA, was interpreted for use. The study results were statistically processed using SPSSWIN(ver 10.0) and conferred the following results: 1. Among the seven items of IADL, the women showed higher rates of 'yes' in items about using the telephone, getting to the places out of walking distance, going shopping for groceries, taking their own medicine while outnumbered by the men only in the item about managing their own money, without significant differences between them in items about preparing their own meals and doing their own housework. 2. In terms of IADL scores, $82.0\%$ of subjects showed the normal range of scores and $18.0\%$ were under the normal range, meaning dysfunction IADL. Specifications of general characteristics revealed that more dysfunctional were the male subjects, the higher age groups who are more than 75 years old, the higher educated groups, the groups who live in nursing homes, the groups without a spouse. 3. Based on daily activities, lower scores of IADL were found in the subjects who don't go out, who don't have recreational activities, who don't attend elderly gatherings in their neighborhood, who don't hold social meetings. Specifications of psychological traits revealed that more dysfunctional were IADL in the subjects who don't feel satisfied with their lives of the past or the present, who have a deep feeling of isolation, and who don't have the will to live. 4. Among 7 items of health habits, only the subjects who don't regular exercise had lower scores of IADL than those who do. According to HPI, the lower HPI, the more dysfunctional. 5. Based on the factors associated with IADL, the odds ratio of the subjects who don't live together with their families were 1.53 times that of the ones who do, who are educated 3.22 times that of the ones who are not, who don't have spouses 2.09 times that of the ones who do, who don't go out 4.35 times that of the ones who frequently go out, who don't recreational activities for an interest 2.64 times that of the ones who do, who don't attend elderly gatherings in their neighborhood 1.47 times that of the ones who do, who don't hold social meetings 2.23 times that of the ones who do, who don't feel satisfied with their present living 1.43 times that of the ones who do, who have a feeling of isolation 1.53times that of the ones who don'1, who have the weak will to live 3.21 times that of the ones who have the strong one, and who don't regular exercise 2.45 times that of the ones who do. 6. Logistic regression analysis of the study results found that such factors are significantly related as the degree of education, with/without spouse, social meetings, the will to live, and regular exercise, and that higher rates of dysfunctional subjects were in the more educated group, in the group without spouse, in the group who don't frequently go out, who don't have social meetings, who have the weak will to live, and who don't exercise.

• Journal of radiological science and technology
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• v.28 no.4
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• pp.333-340
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• 2005

In this study, the radioprotective effects of Grifola umbellata hot water extracts (Gu-extract) on mice were investigated. Single pre-administration of Gu-extract increased the 40-day survival ratio of irradiated mice from 65.5％ to 78.6％. The growth of 3 week old male mice in the irradiated group was slightly retarded as compared to those of the control and Gu-extract treated mice. The average spleen and thymus weights of the irradiated mice were lower than those of the control and Gu-extract treated mice. The weight reduction of testis in the irradiated mice was significant. While it was relatively slight in the Gu-extract treated mice as compared to that of control mice. No significant difference in the weight was observed in heart, kidney or liver among three groups. The leukocytes of the Gu-extract treated mice did not decrease dramatically as in the irradiated group, but recovery patterns were similar in both groups. Reduction of erythrocytes were similar in both groups but its recovery occurred more rapidly in the extract treated group. The glucose level of the Gu-extract treated group did not change during the period examined, while it was still higher in the irradiated group than the level in the control group in two weeks. The cholesterol levels in the irradiated and the Gu-extract treated groups were higher than that of control group on day 7, but decreased to the level of the control group on day 14. No difference was observed in total protein amount of the serum among the three groups. SDS-polyacrylamide gel electrophoresis of the soluble proteins extracted from various organs did not reveal differences to any extent in all groups except in the livers of the irradiated and extract treated groups, in which some proteins were missing or less present.

• Radiation Oncology Journal
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• v.18 no.2
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• pp.101-106
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• 2000

Purpose : This study was peformed to evaluate the effectiveness and tolerance of craniospinal irradiation for patients with modulloblastoma and to define the optimal radiotherapeutic regimen. Materials and Methods : We retrospectively analyzed the records of 43 patients with modulloblastoma who were treated with external beam craniospinal radiotherapy at our institution between May, 1984 and April, 1998. Median follow up period was 47 months with range of 18 to U months. Twenty seven patients were male and sixteen patients were female, a male to female ratio of 1.7:1. Surgery consisted of biopsy alone in 5 patients, subtotal excision in 24 patients, and gross total excision in 14 patients. All of the patients were treated with craniospinal irradiation. All of the patients except four received at least 5,000 cGy to the posterior fossa and forty patients received more than 3,000 cGy to the spinal cord. Results : The overall survival rates at 5 and 7 years for entire group of patients were 57$\%$ and 56$\%$, respectively. Corresponding disease free survival rates were 60$\%$ and 51$\%$, respectively, The rates of disease control in the posterior fossa were 77$\%$ and 67$\%$ at 5 and 7 years. Gross total excision and subtotal excision resulted in 5 year overall survival rates of 76$\%$ and 66$\%$, respectively, In contrast, those patients who had biopsy alone had a 5 year survival rate of only 40$\%$. Posterior fossa was a component of failure in 11 of the 18 recurrences. Seven recurrences were isolated to the posterior fossa. Four patients had neuraxis recurrences, three had distant metastasis alone and four had multiple sites of failure, all involving the primary site. Conclusion : Craniospinal irradiation for patients with moduiloblastoma is an effective adjuvant treatment without significant treatment related toxicitles. There is room for Improvement in terms of posterior fossa control, especially in biopsy alone patients. The advances in radiotherapy including hypefractionation, stereotactic radiosurgery and 3D conformal radiotherapy would be evolved to improve the tumor control rate at primary site.

• Radiation Oncology Journal
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• v.19 no.1
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• pp.16-20
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• 2001

Purpose : To evaluate the effectiveness and tolerance of the postoperative radiation therapy for patients with Stage III thymoma and to define the optimal radiotherapeutic regimen Materials and Methods : We retrospectively analyzed the records of 24 patients with Stage III thymoma who were referred for postoperative radiation therapy in our institution from June, 1987 to May, 1999. Surgical therapy consisted of total resection in one patient, subtotal resection in seventeen, and biopsy alone in six patients. Age of the patients was ranged from 20 to 62 years with mean age of 47 years. Male to female ratio was 14 to 10. Radiation therapy was delivered with linear accelerator producing either 6 MeV or 10 MeV photons. The irradiated volume included anterior mediastinum and known residual disease. The supraclavicular fossae were not irradiated. The delivered total dose was ranged from 30 to 56 Gy. One patient received 30 Gy and eighteen patients received minimum of 50 Gy. Follow up period was ranged from 12 months to 8 years with median follow up of 40 months. Results : The overall local control rate for entire group of patients was $67\%$ at 5 years. The cumulative local failure rates at one, three and five year were $18\%,\;28\%\;and\;33\%$, respectively. In patients treated with subtotal resection and biopsy alone, local control rate was $76\%\;and\;33\%$, respectively. The actuarial observed survival rate at 5 years was $57\%$, and actuarial adjusted survival at 5 years was $72\%$. The difference between 5 year survival rates for patients treated with subtotal resection and biopsy alone was not statistically significant $(62\%\;vs\;30\%)$. Conclusion : We might conclude that postoperative radiation therapy was safe and effective treatment for patients with Stage III thymoma. Postoperative radiation therapy is recommended in cases where tumor margin is close or incomplete resection is accomplished.