• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.90-101
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• 2022

The study aims to assess composition, diversity and population indices of natural regeneration of woody species in Jebel El Gerrie forest reserve, Blue Nile State, Sudan. We conducted field work between December 2018 and January 2019. We used random sampling to collect vegetation data in the forest where we made a total of 90 circular sample plots (radius 17.84 m) and distributed them proportionally to the area of each of the four density-based vegetation classes of the forest i.e. high density (C1), medium density (C2), low density (C3) and crop land (C4). In each sample plot we identified all regenerating tree species and counted their regeneration frequencies. We calculated ecological metrics of regeneration frequency, density, abundance, richness, evenness, diversity and importance value index (IVI) and drew abundance rank curve. Results revealed that out of fifteen mature tree species present, natural regeneration of 8 species, which belong to 6 families, was observed. The relatively most frequently naturally regenerating and abundant species were Anogeissus leiocarpa and Combretum hartmannianum. Richness, evenness and diversity of regenerating species were 1.33, 0.82 and 1.7, respectively. One-way ANOVA (α=0.05) of mean regeneration densities disclosed that there were significant differences (F_3,86=16.77, p=0.000) between C2 & C3 (p=0.000) and C2 & C4 (p=0.000). While regeneration of seven tree species were absent, two, two and four species were of good, poor and fair regeneration status, respectively. A comparison of mean density of natural regeneration with that of parent trees reflects a poor regeneration status of the forest. The study provides empirical results on the regeneration status of species and signifies the need for management interventions for species conservation and restoration, maintenance of biodiversity and sustainable production.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.3 no.2
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• pp.1-15
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• 1983

This paper has concentrated on estimating the possibility and mathematical analysis for the application of BFB to the treatment of nightsoil with low dilution rate. The experiment for the study of this purpose was conducted by continuous type reactor at $20^{\circ}C$, varying F/M ratio from 0.12 to 0.37 and dilution ratio from 2 to 10, and in it provided matted reticulated polypropylene sheets for the solid supports. The obtained results showed that the application of BFB to the treatment of nightsoil would be more effective than any other biological treatment process. Also, it has observed that the optimum dilution ratio was about 5 times and the optimum HRT was about 17 hours, and then it was estimated that the reactor volume and the quantity of weak water could be reduced to the extent of 70 percent and 80 percent. The experimental results of BFB could be analysed by the mathematical models applied to complete mixing activated sludge process. The substrate removal rates which were obtained by McKinney's($K_m$) and EcKenfelder's($K_e$) equation was 1.784/hr and $2.0{\times}10l/mg{\cdot}day$, and substrate was removed very rapidly compared to those of conventional type biological treatment processes. The biomass yield coefficient($a_5$), the endogeneous respiration rate(b), the synthesis oxygen demand rate($a{_5}^{\prime}$), and the endogeneous respiration oxygen demand rate(b') were 0.349, 0.0237/day, 0.495 and 0.0336, respectively.

• Geophysics and Geophysical Exploration
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• v.13 no.3
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• pp.203-218
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• 2010

The site categorization and corresponding site amplification factors in the current Korean seismic design guideline are based on provisions for the western United States (US), although the site effects resulting in the amplification of earthquake ground motions are directly dependent on the regional and local site characteristic conditions. In these seismic codes, two amplification factors called site coefficients, $F_a$ and $F_v$, for the short-period band and midperiod band, respectively, are listed according to a criterion, mean shear wave velocity ($V_S$) to a depth of 30 m, into five classes composed of A to E. To suggest a site classification system reflecting Korean site conditions, in this study, systematic site characterization was carried out at four regional areas, Gyeongju, Hongsung, Haemi and Sacheon, to obtain the $V_S$ profiles from surface to bedrock in field and the non-linear soil properties in laboratory. The soil deposits in Korea, which were shallower and stiffer than those in the western US, were examined, and thus the site period in Korea was distributed in the low and narrow band comparing with those in western US. Based on the geotechnical characteristic properties obtained in the field and laboratory, various site-specific seismic response analyses were conducted for total 75 sites by adopting both equivalent-linear and non-linear methods. The analysis results showed that the site coefficients specified in the current Korean provision underestimate the ground motion in the short-period range and overestimate in the mid-period range. These differences can be explained by the differences in the local site characteristics including the depth to bedrock between Korea and western US. Based on the analysis results in this study and the prior research results for the Korean peninsula, new site classification system was developed by introducing the site period as representative criterion and the mean $V_S$ to a depth of shallower than 30 m as additional criterion, to reliably determine the ground motions and the corresponding design spectra taking into account the regional site characteristics in Korea.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.12
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• pp.1701-1707
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• 2005

This study deals with the characterization of porcine PIK3C3 and association tests with quantitative traits. PIK3C3 belongs to the class 3 PI3Ks that participate in the regulation of hepatic glucose output, glycogen synthase, and antilipolysis in typical insulin target cells such as those in the such as liver, muscle system, and fat. On the analysis of full-length mRNA sequence, the length of the PIK3C3 CDS was recorded as 2,664 bps. As well, nucleotide and amino acid identities between human and pig subjects were 92% and 99%, respectively. Five SNPs were detected over 5 exons. We performed genotyping by using a SNP C2604T on exon24 for 145 F$_2$ animals (from a cross between Korean native boars and Landrace sows) by PCR-RFLP analysis with Hpy8I used to investigate the relationship between growth and fat depot traits. In the total association analysis, which doesn' consider transmission disequilibrium, the SNP showed a significant effect (p<0.05) on body weight and carcass fat at 30 weeks of age as well as a highly significant effect (p<0.01) on back fat. In an additional sib-pair analysis, C allele still showed positive and significant effects (p<0.05) on back fat thickness and carcass fat. Moreover, the effects of C allele on the means of within-family components for carcass fat and back fat were estimated as 2.76 kg and 5.07 mm, respectively. As a result, the SNP of porcine PIK3C3 discovered in this study could be utilized as a possible genetic marker for the selection of pigs that possess low levels of back fat and carcass fat at the slaughter weight.

• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.153-168
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• 2005

The purposes of this study were to determine the influence of midsole hardness and sole thickness of sports shoes on ball flex angle and position with increment of running velocity. The subjects employed for this study were 10 college students who did not have lower extremity injuries for the last one year and whose running pattern was rearfoot striker of normal foot. The shoes used in this study had 3 different midsole hardness of shore A 40, shore A 50, shore A 60 and 3 different sole thickness of 17cm, 19cm, 21cm. The subjects were asked to run at 3 different speed of 2.0m/sec, 3.5m/sec, 5.0m/sec and their motions were videotaped with 4 S-VHS video cameras and 2 high speed video cameras and simultaneously measured with a force platform. The following results were obtained after analysing and comparing the variables. Minimum angle of each ball flex position were increased with the increment of running velocity and shoe sole thickness(P<0.05), but mid-sole hardness did not affect minimum ball flex angle. The position which minimum angle was shown as smallest was 'D'. Midsole hardness and sole thickness did not affect time to each ball flex minimum angle, total angular displacement of ball flex angle, and total angular displacement of torsion angle(P<0.05). The position which minimum angle was appeared to be earliest was similar at walking velocity, and E and F of midfoot region at running velocity. Total angular displacement of ball flex position tended to increase as shifted to heel. It was found that running velocity had effects on ball flex angle variables, but shoe sole thickness partially affected. It would be considered that running velocity made differences between analysis variables at walking and running when designing shoes. Also, it was regarded that shoes would be developed at separated region, because ball flex angle and position was shown to be different at toe and heel region. It is necessary that midsole hardness and thickness required to functional shoes be analyzed in the further study.

• Journal of Practical Agriculture & Fisheries Research
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• v.12 no.1
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• pp.137-150
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• 2010

Traditionally, like many people in mountain region of the Himalaya, the Lwang communities depend on mix of subsistence agriculture, animal husbandry, and seasonal migrant labor for their livelihoods. These traditional systems are characterized by low productivity, diverse use of available natural resources (largely for home consumption), limited markets, and some aversion for innovation. The potential to generate wealth through commerce has largely been untapped by these mountain residents and thus is undervalued in local and national economies. Introduction of organic tea farming is a part of Lwang community's several initiatives to break the vicious poverty cycle Annapurna Conservation Area Project (ACAP) played facilitating roles in all their efforts since beginning. In five years, the tea plantation emerged as a new means for secured a livelihood. This study aims to analyze the current practices in tea farming both in terms of farm management and soil nutrient status(technical) and the prosperity of the tea farmers (social). The technical aspect covers the soil and tea leaf analysis of various nutrients contents in the soil and tea leaf. Originally, the technical aspect of the study was not planned but later during the consultation with the advisor it was taken into consideration which added value to the research study. The sample were collected from different locations and analyzed on the field itself. The other part of the study i.e. the social aspect was done through questionnaire survey and focus group discussion. the tea farming provided them not only a new opportunity but also earned an identity in the region. This initiative was undertaken as a piloting measure. Now that the tea is in production with processing unit established locally, more serious consideration has to be given for better yield and economic prosperity. This research finding will help the community to analyze their efforts and make correction measures in tea garden management and application of fertilizer. It is also expected to fill up the gaps of knowledge and information required to reduce economic stresses and enhance capacity of farmers to make the tea farming a sustainable and beneficial business. The findings are expected to Sustainability of organic tea farming has direct impacts on biodiversity conservation compared to the other traditional farming practices that are more resource intensive. The study will also contribute to identify key action points required for reducing poverty while conserving environment and enhancing livelihoods

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.11
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• pp.1542-1547
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• 2005

The Melanocortin-4 Receptor (MC4R) and Insulin-like Growth Factor 2 (IGF2) are two important candidate genes related to fat deposition and carcass traits. MC4R was found on study on human obesity and then was studied as candidate gene affecting food intake and fat deposition traits in mice and pigs. Insulin-like Growth Factor 2 (IGF2) gene plays an important role on tumor cell proliferation and muscle growth. It also affects fat traits and live weight in pigs. In this paper, MC4R and IGF2 were studied as two candidate genes associated with important economic traits such as fat deposition and carcass traits in five different pig populations. Taq I-PCR-RFLP and Bcn I-PCR-RFLP were respectively used to detect the polymorphism of genotypes of MC4R and IGF2 genes. Different MC4R genotype frequencies were observed in four populations. IGF2 genotype frequencies were also different in two populations. The results of association analysis show both MC4R and IGF2 genes were significantly associated with fat deposition and carcass traits in about 300 pigs. This work will add new evidence of MC4R and IGF2 affecting fat deposition and carcass traits in pigs and show that two genes can be used as important candidate genes for marker assistant selection (MAS) of growth and lean meat percentage in pigs.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.11
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• pp.1999-2010
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• 1992

The fixed slab analogy device which can measure stress intensity factors(S.I.F) experimentally by slab analogy theory is developed in this paper. The margin of errors resulted from the new testing apparatus are between 0.02% and 8.25%. Therefore, it is assured that this one can be effectively used for the more accurate measurement of S.I.F.( $k_{I}$, $k_{I I}$) than conventional apparatus. The pitch of master grating used in this experiment is 0.1mm It is known that the ratio of the distance from crack tip to the crack length on obtaining the accurate stress intensity factor is between 0.4 and 0.7. The optimum curvature radius of slab is about 125mm. The thickness of slab(plate) used in the fixed slab analogy device is 0.05mm(P.V.C. ; E = 64 MN/ $m^{2}$, .nu.=0.38), which is proved to be suitable for the test. The optimum material for the frame(slab`s external boundary) is a alloy tool steel(SKS 5) plate and its thickness is 1mm. In this research, the rigid cracks are directly bonded to the slab surface by cyanoacrylate adhesive for the easiness of slab making and conformity to the practical crack figure. The material of rigid crack is thin steel plate. It is expected that the developed method can be used effectively for the analysis of $k_{I}$ and $k_{I I}$ of arbitrary shaped or distributed cracks.cks.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.324-328
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• 2006

Carbonic anhydrase III (CA3) is a member of a multigene family that encode carbonic anhydrase isozymes. In this study, a complete coding sequence of the pig CA3 gene which encodes a 260 amino-acid protein was determined. The amino acid comparison showed high sequence similarities with previously identified human (86.5%) CA3 gene and mouse (91.5%) Car3 gene. The partial genomic DNA sequences were also investigated. The length of intron 1 was 727 bp. Comparative sequencing of three pig breeds revealed that there was a T${\rightarrow}$C substitution at position 363 within intron 1. The substitution was situated within a NcoI recognition site and was developed as a PCR-restriction fragment length polymorphism (RFLP) marker for further use in population variation investigations and association analysis. Two alleles (A and B) were identified, and 617 bp fragments were observed for the AA genotype and 236 bp and 381 bp fragments for the BB genotype. The polymorphism of CA3 was detected in 8 pig breeds. Allele B was predominant in the Western pig breeds. In addition, association studies of the CA3 polymorphism with carcass traits in 140 $Yorkshire{\times}Meishan$ $F_2$ offspring showed that the NcoI PCR- RFLP genotype may be associated with variation in several carcass traits of interest for pig breeding. Allele B was associated with increases in lean meat percentage, loin eye height and loin eye area. Statistically significant association with backfat thickness was also found; pigs with the AB genotype had much less backfat thickness than AA or BB genotypes.

• Journal of Korean Society on Water Environment
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• v.24 no.4
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• pp.423-429
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• 2008

Microfiltration (MF) and ultrafiltration (UF) processes for removal of particulate materials (i.e., turbidity, microorganisms and viruses) have been used to produce drinking water with higher quality. As membrane filtration technique has become widely applied for drinking water treatment, the importance of membrane integrity test (MIT) has also been increasingly emphasized. The results of pressure decay test (PDT) were presented in the paper to monitor membrane integrity. In this paper the PDT was carried out with deliberately-defected membrane fibers to evaluate the sensitivity of PDT on membrane fiber damage. Variation of pressure decay rate and removal rate were investigated to evaluate the impact of defection (defection ratio) and pore size of membrane. The membrane integrity could be successfully monitored by the PDT. The pressure decay rate varied from $0.002{\sim}0.189kg_f/cm^2hr$ with the initial pressure ranged from 0.2 to $1.0kg_f/cm^2hr$. Higher initial pressure which provided with higher pressure decay rate was preferred to evaluate the defection of membrane fiber. As for the particle removal rate, the Log Removal Rate (LRV) of kaolin solution decreased significantly from 3.78 to 2.31 when one fiber out of 3,200 fibers was cut. The membranes with different pore size were tested to evaluate virus removal efficiency. The virus removal rate of the MF membrane ($0.1{\mu}m$) was about 30% although the poliovirus was smaller than the pore size of the MF membrane, indicating that the removal rate was much lower than Korea Water Works Association (KWWA) certificate LRV of 1.5.