• Korean Journal of Applied Biomechanics
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• v.33 no.4
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• pp.175-184
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• 2023

Objective: The purpose of this study is to investigate the effects of human motion and javelin kinematics during the energy transfer in javelin throwing on records, and to provide evidence-based training insights for athletes and coaches to enhance records. Method: Three javelin throw athletes (age: 22.67 ± 0.58 years, height: 178.33 ± 7.37 cm, weight: 83.67 ± 1.15 kg) were recruited for this study. Each athlete attempted ten maximum record trials, and the kinematic data from each performance were analyzed to determine their influence on the records. The Theia3d Markerless system was used for motion analysis. Results: Key factors were modeled and identified at each moment. In E1, main variables were COM Y (𝛽 8.162, p<.05) and COM velocity Z (𝛽 -72.489, p<.05); in E2, COM X (𝛽 -17.604, p<.05); in E3, COM X (𝛽 -18.606, p<.05), COM velocity Y (𝛽 38.694, p<.05), and COM velocity X (𝛽 66.323, p<.05). For the javelin throw dynamics in E3, key determinants were Attitude angle and Javelin velocity in the Y-axis. Conclusion: The study reveals that controlled vertical movement, center of mass management during braking, and enhanced pelvic rotation significantly improve javelin throw performance. These kinematic strategies are critical for record enhancement in javelin throwing.

• Journal of Microbiology and Biotechnology
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• v.20 no.2
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• pp.301-310
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• 2010

Bacillus subtilis strains produce a broad spectrum of bioactive peptides. The lipopeptide surfactin belongs to one well-known class, which includes amphiphilic membrane-active biosurfactants and peptide antibiotics. Both the srfA promoter and the ComP-ComA signal transduction system are an important part of the factor that results in the production of surfactin. Bs-M49, obtained by means of low-energy ion implantation in wild-type Bs-916, produced significantly lower levels of surfactin, and had no obvious effects against R. solani. Occasionally, we found strain Bs-M49 decreased spore formation and the development of competence. Blast comparison of the sequences from Bs-916 and M49 indicate that there is no difference in the srfA operon promoter PsrfA, but there are differences in the coding sequence of the comA gene. These differences result in three missense mutations within the M49 ComA protein. RT-PCR analyses results showed that the expression levels of selected genes involved in competence and sporulation in both the wild-type Bs-916 and mutant M49 strains were significantly different. When we integrated the comA ORF into the chromosome of M49 at the amyE locus, M49 restored hemolytic activity and antifungal activity. Then, HPLC analyses results also showed the comA-complemented strain had a similar ability to produce surf actin with wild-type strain Bs-916. These data suggested that the mutation of three key amino acids in ComA greatly affected the biological activity of Bacillus subtilis. ComA protein 3D structure prediction and motif search prediction indicated that ComA has two obvious motifs common to response regulator proteins, which are the N-terminal response regulator receiver motif and the C-terminal helix-turn-helix motif. The three residues in the ComA N-terminal portion may be involved in phosphorylation activation mechanism. These structural prediction results implicate that three mutated residues in the ComA protein may play an important role in the formation of a salt-bridge to the phosphoryl group keeping active conformation to subsequent regulation of the expression of downstream genes.

• The Korean Journal of Pesticide Science
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• v.14 no.3
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• pp.241-246
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• 2010

Field experiments were carried out to establish economic threshold for com borer (Ostrinia furnacalis (Guen$\'{e}$e)) on waxy com plants by examining the number of adult insects caught in pheromone traps and the injury levels of waxy com which were artificially controlled. Adult com borers were lured into the pheromone traps during the whole growth period in five areas in Gangwon province including Chuncheon. The number of com borers trapped was the greatest in Chuncheon followed by Cheolwon and Hongcheon, and the same trend was observed for injury level of waxy com. Based on marketable yield data of waxy com plants related to the artificially-controlled injury levels at tassel stage, spray threshold was determined as the injury level of 11~15%, where the injury of com plants exceeded the economically admitting level.

• Korean Management Science Review
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• v.17 no.3
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• pp.181-201
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• 2000

This paper performs a case study on an Internet business networking company, oneQ.com. We define the functions of Internet business networker and discuss its characteristics such as network effect, lock-in effect, and increasing returns etc. Through reviewing the business models, strategies, and implemented technologies of the oneQ.com, we investigate the applicability and effectiveness of the Internet business networker as well as its research implications.

• Annual Conference of KIPS
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• 2000.10b
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• pp.1313-1316
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• 2000

최근 GIS 기술이 급속도로 발전됨에 따라, 시스템 사용자들은 그 어플리케이션이 사용하는 3차원 지리정보가 어떠한 포맷을 가진 데이터인지에 상관없이 동작하기를 원하고 있다. 그러나, 대부분의 3차원 GIS 어플리케이션 시스템들은 시스템에 종속적인 데이터 포맷을 가진 지리정보를 이용하고 있다. 따라서, 이 연구에서는 각각의 목적에 따라 사용하고 있는 어플리케이션들을 수정하는 일없이 어떠한 환경에서의 데이터 서버 시스템에서라도 동작이 가능하도록 3차원 지리정보시스템을 위한 표준 인터페이스를 가진 데이터 제공자를 설계한다. 이 데이터 제공자는 OGC에서 제안한 OLE/COM 구현 사양을 따른다.

• Korean Journal of Cleft Lip And Palate
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• v.4 no.2
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• pp.51-68
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• 2001

Midfacial hypoplasia in patients with clefts of the lip and palate is considered to be the result of congenital dysmorphogenesis. And cleft lip and palate developes facial deformity, jaw abnormality, speech problem, which is most frequent hereditary deformity in maxillofacial region. So cleft lip and palate is characterized by midface deformity which shaws maxillary anterior nasal septal deviation and deformity. Our study describes congenital correlates of midfacial hypoplasia by examining the displacement of a normal complement of parts, a triangular tissue deficiency low on the lip border on the columellar side, and a linear deficiency and displacement in the line of the bilateral cleft lip. 15 patients with bilateral cleft lip and palate were taken impression before operation, but the patient who had other abnormalities and complications were excluded. Average age is 3.4 months and they were classified into both complete, both incomplete and complete & incomplete group. The obtained results were as follows 1. There were no differences on intercanthal width and canthal width between each of the groups. 2. Both complete group had longer lateral ala length than both incomplete group, but there were no differences between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 3. Columella length was greater in both incomplete group than in both complete group, but there was no difference between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 4. Both complete group had longer ala width & ala base width than both incomplete group had. But there were no differences between both complete group and complete side of com. & incom. group and both incomplete group and incomplete side of com. & incom. group. 5. There were no differences between each of the groups on upper lip length, but nose/mouth width ratio was greater in both complete group than in both incomplete group. 6. Pronasale(pm), subnasle(sn), la~rale superioris(ls), stomion(sto) points were located around the central vertical line of face but deviated to incomplete side in com. & incom. group. 7. Nasal tip protrusion was greater in both incomplete group and com. & incom. group than both complete group, but there was no difference between both incomplete group and com. & incom. group.

• Journal of Animal Science and Technology
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• v.63 no.6
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• pp.1362-1375
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• 2021

This study was conducted to evaluate the efficacy of a combination 3,4,5-trihydroxybenzoic acid (THB) and oregano extracts (i.e., Carvacrol and Thymol) at intake/dietary different levels on growth performance, intestinal health indicators, immune responses and fecal oocyst shedding in broiler chickens under Eimeria challenged condition. A total of 336 one-day-old broilers were randomly assigned to one of six dietary treatments with seven replications per treatment. Dietary treatments were: i) Non-challenged bird without any dietary treatment (NCNT), ii) Challenged bird without any dietary treatment (CNT), iii) Challenged birds fed a THB diet (0.1 g/kg, THB), iv) Challenged birds fed a combination of THB and oregano extracts diet (0.1 g/kg, COM 100), and a gradual increase of combination of THB and oregano extracts likely v) 0.15 g/kg (COM 150), and 0.2 g/kg (COM 200). On day 14, all groups except for NCNT have orally challenged with a 10-fold dose of Livacox^® T anticoccidial vaccine to trigger coccidiosis. The results indicated that Eimeria-challenged broilers fed COM 100 and COM 200 diets increased (p < 0.05) body weight than CNT diet on day 35. Furthermore, birds fed COM 100 and COM 200 diets increased (p < 0.05) average daily gain compared to those fed CNT diets for the entire experimental period. There is no significant (p > 0.05) in average daily feed intake, feed efficiency between NCNT and birds fed with combined THB and oregano extracts for the entire experimental period. A combination of THB and oregano extract regardless of concentration levels or THB alone reduced (p < 0.05) lesion score in ileum compared to the CNT diet for 7 days post-infection (dpi). Birds fed COM 100 diet had lower (p < 0.05) intestinal lesion scores in jejunum and caeca on 7 dpi compared to those were in the CNT diet. No (p > 0.05) difference was observed in the oocysts per gram of feces count, intestinal morphology, carcass traits and blood cytokine concentration among the infected treatments. Collectively, we conclude that birds fed with a combination of THB and oregano extracts regardless of the ratios that were used demonstrated better recovery of health after the coccidial challenge than using only THB alone.

• Journal of Engineering Education Research
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• v.16 no.3
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• pp.3-9
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• 2013

It is very difficult for students to understand "Computer System Architecture" written by M. Morris Mano only through theoretical education. This study has developed DigCom as a computer architecture practice kit to make it easier for students to understand computer operations. The practice kit operates in the same manner as the "simple computer" described in Computer System Architecture. The purpose of this study is to examine whether using DigCom is effective in improving learning outcomes. For the purpose, t-test and two-way ANOVA were used to determine if there is any difference in learning outcomes between the experimental group of students who used DigCom and the control group who took the course in a traditional setting without using DigCom. The main conclusions of the study are as follows: Students understand computer operations better when DigCom is used in class.

• Journal of the Korean Society of Safety
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• v.33 no.6
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• pp.144-156
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• 2018

Level 3 Probabilistic Safety Assessment (PSA) is performed for the risk assessment that calculates radioactive material dispersion to the environment. This risk assessment is performed with a tool of MELCOR Accident Consequence Code System (MACCS2 or WinMACCS). For the off-site consequence analysis of multi-unit nuclear power plant (NPP) accident, the single location (Center Of Mass, COM) method has been usually adopted with the assumption that all the NPPs in the nuclear site are located at the same COM point. It was well known that this COM calculation can lead to underestimated or overestimated radionuclide concentration. In order to overcome this underestimation or overestimation of radionuclide concentrations in the COM method, Multiple Location (ML) method was developed in this study. The radionuclide concentrations for the individual NPPs are separately calculated, and they are summed at every location in the nuclear site by the post-processing of radionuclide concentrations that is based on two-dimensional Gaussian Plume equations. In order to demonstrate the efficiency of the ML method, radionuclide concentrations were calculated for the six-unit NPP site, radionuclide concentrations of the ML method were compared with those by COM method. This comparison was performed for conditions of constant weather, yearly weather in Korea, and four seasons, and the results were discussed. This new ML method (1) improves accuracy of radionuclide concentrations when multi-unit NPP accident occurs, (2) calculates realistic atmospheric dispersion of radionuclides under various weather conditions, and finally (3) supports off-site emergency plan optimization. It is recommended that this new method be applied to the risk assessment of multi-unit NPP accident. This new method drastically improves the accuracy of radionuclide concentrations at the locations adjacent to or very close to NPPs. This ML method has a great strength over the COM method when people live near nuclear site, since it provides accurate radionuclide concentrations or radiation doses.

• Korean Journal of Applied Biomechanics
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• v.20 no.3
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• pp.261-266
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• 2010

Human body is hard to be in perfect balance during walking. Most of time the trunk is supported by one leg and the center of mass(COM) falls to the contralateral side. Thus, dynamic variables such as the velocity of the COM should be considered when gait stability is evaluated. The purpose of this study was to investigate whether the extrapolated center of mass(XCom) which utilized the COM position and its velocity, is appropriate to evaluate gait stability. Ten healthy adults participated in this study and performed 3 different types of gaits(normal(NG), hands on waists(HWG), and hands on shoulders(HSG)) onto 4 different types of obstacle(obstacle height: 0%, 30%, 40% and 50% of leg length). Medio-lateral Com-CoP and XCom-CoP inclination angle were calculated during support phase. For all condition, greater M-L XCoM-CoP inclination angles were found(p<.05) compared with those of matched obstacle height CoM-CoP. Especially, M-L XCoM-CoP inclination angle at 50% height revealed the best condition for monitoring dynamic stability. Significantly increased in M-L XCoM-CoP inclination angle was found(p<.05) as obstacle height increased on NG and HWG.