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Assessment of Optimum Hydraulic Retention Time (HRT) for Maximum Biogas Production and Total Volatile Solid (TVS) Removal Efficiency of Semi-Continuously Fed and Mixed Reactor (SCFMR) Fed with Dairy Cow Manure (젖소분뇨로부터 최대 바이오가스 생산과 유기물 제거효율을 달성하기 위한 반건식 간헐주입 연속혼합 혐기성반응조의 최적 수리학적 체류시간 도출을 위한 연구)

  • Kang, Ho;Kim, Sun-Woo;Jeong, Ji-Hyun;Ahn, Hee-Kwon;Jung, Kwang-Hwa
    • 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.

Analysis on the Use Characteristics of Citizen based on Urban Green Spaces Type - Focuses on Suwon-City - (도시녹지 유형에 따른 도시민의 이용 특성 연구 - 수원시를 대상으로 -)

  • Kim, Yea Sung;Kim, Hyun;Ko, Jinsoo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.42 no.5
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    • pp.31-40
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    • 2014
  • The importance of green spaces in the city is growing each day. Local governments are taking charge of park development works that are having difficulty in developing and managing urban parks due to high land value as well as a shortage in finances. This is even though an urban park is defined as an urban planning facility and the law provides park area per person. Civil residents, meanwhile, are using not only urban parks provided by law but also other green areas such as rivers, reservoirs, and school playgrounds because they recognize urban green areas by the concept of use. In this study, accordingly, urban green areas were sorted into two types, urban parks, parks provided by law, and other green areas, and the difference in use pattern and use satisfaction by type was analyzed. As a result of analysis, there was no remarkable difference between the two types. According to such results, it was found that it is necessary to include other green areas, such as rivers, reservoirs, school green areas, and apartment green areas in addition to the current park green areas provided by law when park area per person is calculated, and such calculation of urban green areas reflecting local characteristics can reduce local governments' financial burden and improve the effectiveness of future urban park policies. It is judged that such results can become a plan against the cancellation of unexecuted urban facilities. The fact that accessibility factors, such as road satisfaction, access convenience, and convenient movement, are affecting satisfaction with the use of urban parks suggests that it is important to improve urban park accessibilities rather than to quantitatively expand park area in order to improve satisfaction with urban parks. Considering that people travel to urban green areas mostly by walking, it is necessary for access convenience to conduct follow-up studies such as barrier-free and securing walking stability through analysis of routes to urban green areas.

Variation of Lignan Content for Sesame Seed Across Origin and Growing Environments (참깨 원산지 및 재배지역에 따른 리그난 함량 변이)

  • Kim, Sung-Up;Oh, Ki-Won;Lee, Myoung-Hee;Lee, Byoung-Kyu;Pae, Suk-Bok;Hwang, Chung-Dong;Kim, Myung-Sik;Baek, In-Youl;Lee, Jeong-Dong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.2
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    • pp.151-161
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    • 2014
  • Sesame lignan, including sesamin and sesamolin has been reported to have various content according to accessions and environmental factors. The objective of this study were to analyze the lignan variation of 143 sesame accessions from core collection in Korea and to test the effects of growing years and locations on lignan and lipid content of Korea sesame elite lines. The results showed that the core sesame germplasm in Korea has broad variation of lignan content from 2.33 to 12.17 mg/g with an average 8.18 mg/g. Among tested sesame accessions, the IT184615 had the highest lignan content of as 12.17 mg/g. So this accession will be a good genetic resource for developing a high lignan sesame variety. The sesamin and sesamolin content for sesame accessions across origin had significant difference. The average lignan content of accessions collected from Russia (10.0 mg/g) and Nepal (9.08 mg/g) were relatively higher than other countries. The sesamin and sesamolin content for sesame accessions across seed coat color had significant difference. The average lignan content of sesame with white, brown and black seed coat color was 8.61, 7.51, and 5.49 mg/g, respectively. The variation of lignan and lipid content was significantly different across elite lines, locations and growing years. Therefore, it is important to find sesame accessions having high lignan content with environmental stability.

Parkin Interacts with the PDZ Domain of Multi-PDZ Domain Protein MUPP1 (Parkin과 Multi-PDZ Domain Protein (MUPP1) 단백질 간의 PDZ 결합)

  • Jang, Won Hee;Jeong, Young Joo;Choi, Sun Hee;Lee, Won Hee;Kim, Mooseong;Kim, Sang-Jin;Urm, Sang-Hwa;Moon, Il Soo;Seog, Dae-Hyun
    • Journal of Life Science
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    • v.24 no.8
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    • pp.820-826
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    • 2014
  • The localization to specific subcellular sites and the regulation of cell surface receptors and channels are crucial for proper functioning. Postsynaptic density-95/Disks large/Zonula occludens-1 (PDZ)-domain is involved in recognition of and interaction between various proteins, by which the localization and the regulation are mediated. Multi-PDZ domain protein 1 (MUPP1) contains 13 PDZ domains. MUPP1 serves a scaffolding function for structure proteins and signaling proteins, but the mechanism how MUPP1 is stabilized and signalized has not yet been elucidated. We used the yeast two-hybrid system to identify proteins that interact with PDZ domains of MUPP1. We found an interaction between MUPP1 and Parkin. Parkin is an E3 ubiquitin ligase. Loss-of-function mutations of Parkin gene are known to cause an autosomal recessive juvenile parkinsonism. Parkin bound to the $12^{th}$ PDZ domain, but not to other PDZ domains of MUPP1. The C-terminal end of Parkin has a type II PDZ-association motif, which was essential for the interaction with MUPP1 in the yeast two-hybrid assay. When co-expressed in HEK-293T cells, Parkin co-localized with MUPP1. When co-expressed with ubiquitin in HEK-293T cells, MUPP1 has been strongly ubiquitinated by Parkin. These findings collectively suggest that MUPP1 is a novel substrate of Parkin and its function or stability could be modulated by Parkin-mediated ubiquitination.

Uplift Bearing Capacity of Spiral Steel Peg for the Single Span Greenhouse (온실용 나선철항의 인발저항력 검토)

  • Lee, Bong Guk;Yun, Sung Wook;Choi, Man Kwon;Lee, Si Young;Moon, Sung Dong;Yu, Chan;Yoon, Yong Cheol
    • Protected Horticulture and Plant Factory
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    • v.23 no.2
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    • pp.109-115
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    • 2014
  • This study examined the uplift bearing capacity of spiral steel pegs according to the degree of soil compaction and embedded depth in a small-scaled lab test. As a result, their uplift bearing capacity increased according to the degree of soil compaction and embedded depth. The uplift bearing capacity under the ground condition of 85% compaction rate especially recorded 48.9 kgf, 57.9 kgf, 86.2 kgf and 116.6 kgf at embedded depth of 25 cm, 30 cm, 35 cm and 40 cm, respectively, being considerably higher than under other ground conditions. There were huge differences in the uplift bearing capacity of spiral steel pegs according to the compaction conditions of ground. Their maximum uplift bearing capacity was 116.6 kgf under the ground condition of 85% compaction rate and at embedded depth of 40 cm, and it is very high considering the data of spiral steel pegs. It is thus estimated that wind damage can be effectively reduced by careful maintenance of ground condition surrounding spiral steel pegs. In addition, spiral steel pegs will be able to make a contribution to greenhouse structural stability if proper installation methods are provided including the number and interval according to the types of greenhouse as well as fixation of plastic film. The findings of the study indicate that the optimal effects of spiral steel pegs for greenhouse can be achieved at embedded depth of more than 35cm and compaction degree of more than 85%. The relative density of the model ground in the test was 67% at compaction rate of 85%.

Negative Support Reactions of the Single Span Twin-Steel Box Girder Curved Bridges with Skew Angles (단경간 2련 강박스 거더 곡선교의 사각에 따른 부반력 특성)

  • Park, Chang Min;Lee, Hyung Joon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.4
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    • pp.34-43
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    • 2012
  • The behaviors of the curved bridges which has been constructed in the RAMP or Interchange are very complicate and different than orthogonal bridges according to the variations of radius of curvature, skew angle and spacing of shoes. Occasionally, the camber of girder and negative reactions can be occurred due to bending and torsional moment. In this study, the effects on the negative reaction in the curved bridge were investigated on the basis of design variables such as radius of curvature, skew angle, and spacing of shoes. For this study, the twin-steel box girder curved bridge with single span which is applicable for the RAMP bridges with span length(L) of 50.0m and width of 9.0m was chosen and the structural analysis to calculate the reactions was conducted using 3-dimensional equivalent grillage system. The value of negative reaction in curved bridges depends on the plan structures of bridges, the formations of structural systems, and the boundary conditions of bearing, so, radius of curvature, skew angle, and spacing of shoes among of design variables were chosen as the parameter and the load combination according to the design standard were considered. According to the results of numerical analysis, the negative reaction in curved bridge increased with an decrease of radius of curvature, skew angle, and spacing of shoes, respectively. Also, in case of skew angle of $60^{\circ}$ the negative reaction has been always occurred without regard to ${\theta}/B$, and in case of skew angle of $75^{\circ}$ the negative reaction hasn't been occurred in ${\theta}/B$ below 0.27 with the radius of curvature of 180m and in ${\theta}/B$ below 0.32 with the radius of curvature of 250m, and in case of skew angle of $90^{\circ}$ the negative reaction hasn't been occurred in the radius of curvature over 180m and in ${\theta}/B$ below 0.38 with the radius of curvature of 130m, The results from this study indicated that occurrence of negative reaction was related to design variables such as radius of curvature, skew angle, and spacing of shoes, and the problems with the stability including negative reaction will be expected to be solved as taken into consideration of the proper combinations of design variables in design of curved bridge.

Effect of Release of the Superficial Medial Collateral Ligament in Repair of the Posterior Medial Meniscus Root Tear (내측 반월상 연골 후각 부착부 봉합술 시 표층 내측측부인대 유리술의 효과)

  • Yang, Byung Se;Lee, Dhong Won;Nam, Sang Wook;Ha, Jeong Ku;Kim, Jin Goo
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.2
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    • pp.114-120
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    • 2012
  • Purpose: The purpose of the study was to evaluate the usefulness and the stability of the superficial medial collateral ligament (MCL) release in posterior medial meniscus root repair. Materials and Methods: We compared 20 patients who underwent posterior medial meniscus root repair with superficial MCL preserved (PM) and 32 patients who underwent posterior medial meniscus root repair combined with superficial MCL release (RM) from April 2006 to September 2010. We excluded the patients combined with other surgery. To evaluate the postoperative valgus instability in RM group, we examined direct tenderness on MCL insertion, the subjective feeling of instability and valgus stress test at 3 months and 1 year follow-up. We compared the tourniquet time between PM group and RM group, and the clinical results were assessed by Lysholm score and International Knee Documentation Committee (IKDC) for the usefulness. Results: All patients had no clinically significant complication related to the superficial MCL release. Three months and 1 year follow-up, there were no positive tenderness test, no subjective symptoms and no significant increase of valgus instability although 5 patients examined grade I valgus instability. The mean tourniquet time was $41.3{\pm}12.7$ minutes in RM group and $53.5{\pm}13.6$ minutes in PM group. There was a significant difference in the tourniquet time between the two groups (P<0.05). Average Lysholm score was $56.8{\pm}5.5$ (range, 44-70) preoperatively and $85.1{\pm}5.8$ (range, 77-94) postoperatively in PM group, and was $56.2{\pm}5.4$ (range, 45-67) preoperatively and $87.4{\pm}3.9$ (range, 82-95) postoperatively in RM group (P<0.001). No significant difference of Lysholm score was found in both groups (P<0.05). Average IKDC scores was $42.6{\pm}3.9$ (range, 30-53) preoperatively and $77.2{\pm}6.3$ (range, 68-92) postoperatively in PM group, and was $42.7{\pm}5.7$ (range, 30-53) preoperatively and $89.6{\pm}2.9$ (range, 84-95) postoperatively in RM group (P<0.05). There was also no significant difference of IKDC score in both groups (P<0.05). Conclusion: The superficial MCL release in posterior medial meniscus root repair is useful to gain a wide surgical field and reduces the tourniquet time and does not lead to postoperative valgus instability. It can be considered clinically useful and safe procedure in medial meniscus posterior root repair.

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Clinical Results of ACL Reconstruction in the Immature Adolescent via Transphyseal Approach in Tibia Based on a New Indication Paradigm (새로운 수술적응증에 의한 골 미성숙 전방십자인대 손상 환자에서의 성장판을 통과하는 전방십자인대 재건술의 결과)

  • Lee, Dong Chul;Shon, Oog Jin;Park, Chul-Hyun;Kwon, Moon Soo
    • Journal of the Korean Arthroscopy Society
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    • v.16 no.1
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    • pp.1-8
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    • 2012
  • Purpose: To evaluate clinical and radiologic outcomes of transphyseal anterior cruciate ligament (ACL) reconstruction in patients with open physes who were selected with authors' new operative indications. Materials and Methods: We evaluated 15 patients with open physes who underwent a transtibial ACL reconstruction and were followed up for 4~6 years after surgery. Our operative indications involved 1) choronologic age of ${\geq}$ 16 in male and ${\geq}$ 14 in female, 2) open physes of ${\leq}$ 2 mm width, and 3) Risser sign and Tanner stage of ${\geq}$ 3. Tibialis anterior tendon allograft was used in all patients, and endobutton and bioscrew were used for femoral and tibial fixations, respectively. Functional outcomes were evaluated using Lysholm Knee Scoring scale, Tegner activity scale, and International Knee Documentation Committee (IKDC) 2000 subjective score. Physical examinations to evaluate stability involved Lachman and pivot shift tests. For radiographic results, we evaluated side to side differences of anterior displacement in stress views. In addition, with use of scannograms taken at last follow-up, we examined side to side differences of femorotibial angles, anatomical and mechanical lateral distal femoral angles, mechanical medial proximal tibial angles and leg lengths. Results: The mean Lysholm Knee score was 51(40-61) points preoperatively and 97(94-100) points at last follow up. The mean Tegner activity score was 2.6 points preoperatively and 7.1 points at last follow up. The mean IKDC score was 32.6 points preoperatively and 88.3 points at last follow up. The mean anterior displacement of the tibia was improved from 6.7(${\pm}1.0$) mm to 1.9(${\pm}0.9$) mm. There were no leg length discrepancies over 5 mm and no statistically significant differences in all the radiographic variables representing growth disturbance. Conclusion: This study suggests that patients with open physes who selected by authors' new indication would safely undergo transphyseal ACL reconstruction with successful outcomes.

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Thermal and Electrochemical Stability of Morpholinium Ionic Liquids (모폴린계 이온성 액체의 열 및 전기화학적 안정성)

  • Kim, Hyun-Taek;Hong, Yeon Ki;Kang, Jeong Won;Lee, Young-Woo;Kim, Ki-Sub
    • Korean Chemical Engineering Research
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    • v.50 no.4
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    • pp.702-707
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    • 2012
  • During the last few decades, toxic chemicals used in various industries have caused global pollution and the side products such as carbon dioxide and methane gas have contributed to global warming. Thus, it is desirable to develop new alternative solvents. It is well known that ionic liquids display a variety of environmentally friendly physical properties: nonvolatile, nonflammable, wide electrochemical windows, high inherent conductivities, wide thermal operating ranges, chemically inert, and limited miscibilities with organic solvents. Because of these characteristics, ionic liquids are promising candidates as solvents for synthetic chemistries, catalysis, and gas separations. In this study, we synthesized morpholiunium salts as N-ethyl-N-methylmorpholine Bromide, N-butyl-N-methylmorpholine Bromide, N-octyl-N-methylmorpholine Bromide, N-ethyl-N-methylmorpholine Tetrafluoroborate, N-butyl-N-methylmorpholine Tetrafluoroborate, N-octyl-N-methylmorpholine Tetrafluoroborate, N-ethyl-N-methylmorpholine Hexafluorophosphate, N-butyl-N-methylmorpholine Hexafluorophosphate, and N-octyl-N-methylmorpholine Hexafluorophosphate. The melting points, decomposition temperatures and electrochemical stabilities of the salts were measured by DSC, TGA, and CV, respectively. The salts with halide anion showed high melting points ($150{\sim}200^{\circ}C$), low decomposition temperatures ($200{\sim}230^{\circ}C$), narrow electrochemical stabilities (3.4~3.6 V). The synthesized salts with inorganic anions, on the other hand, presented low melting point ($50{\sim}110^{\circ}C$), high decomposition temperatures ($250{\sim}380^{\circ}C$), wide electrochemical stabilities (6.1~6.3 V). We also found that the properties depend on the length of the carbon chain.

Retention of CAD/CAM Metal Copings Cemented on Short Titanium Abutments with Different Cements (짧은 티타늄 지대주에 합착된 CAD/CAM 금속 코핑의 시멘트 종류에 따른 유지력 비교)

  • Kim, Hyo-Jung;Song, Eun-Young;Yoon, Ji-Young;Lee, Si-Ho;Lee, Yong-Keun;Oh, Nam-Sik
    • Journal of Dental Rehabilitation and Applied Science
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    • v.28 no.2
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    • pp.119-126
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    • 2012
  • State of problem: Cement-retained implant-supported prostheses are routinely used in dentistry. The use of high strength cements has become more popular with the increasing confidence in the stability of the implant-abutment screw connection and the high survival rates of osseointegrated implants. No clinical data on retention of metal copings using CAD/CAM. To evaluate retention of metal copings using CAD/CAM system bonded to short titanium abutment with four different cements and compare retentive strength of metal copings with sandblasting or without sandblasting before cementation. Forty titanium abutment blocks were fabricated and divided into 4 groups of 10 samples each. Forty metal copings with occlusal hole to allow for retention testing were fabricated using CAD/CAM technology. The four cements were Fujicem(Fuji, Japan), Maxcem Elite(Kerr, USA), Panavia F2.0(Kurarary, Japan) and Superbond C&B(Sunmedical, Japan). The copings were cemented on the titanium abutment according to manufacture's recommendation. All samples were stored for 24h at 37oC in 100% humidity and tested for retention using universal testing machine(Instron) at a crosshead speed of 1.0mm/min. Force at retentive failure was recorded in Newton. The mode of failure was also recorded. Means and standard deviations of loads at failure were analyzed using ANOVA and Paired t-test. Statistical significance was set at P<0.05. Panavia F2.0 provided significantly higher retentive strength than Fujicem, Maxcem Elite(P<0.05). Sandblasting significantly increased bond strength(P<0.05). The mode of failure was cement remaining principally on metal copings. Within the limitation of this study, Panavia F2.0 showed significantly stronger retentive strength than Fujicem, Maxcem Elite(p<0.05). The Ranking order of the cements to retain the copings was Panavia F2.0, Fujicem = Maxcem Elite. Sandblasting significantly increased bond strength(P<0.05). The retentive strength of metal copings on implant abutment were influenced by surface roughness and type of cements.