• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• v.9 no.2
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• pp.204-207
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• 2005

Until present, most studies about energy efficiency of quadruped walking robot are mathematical modelings, dynamic analysis or simulation consumption energy per period by basic efficiency evaluate in this paper, a quadruped walking robot Titan-VIII is used for walking experience. The total moving length is about 2[m]. The stride length is 0.1, 0.2, 0.3, walking period is changed by 1.0, 1.5, 2.0, 3.0[sec] per each stride length. So consumption energy of 12 cases are measured. The energy efficiency of quadruped walking robot was analyzed by data that is saved by an experiment.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.242-246
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• 2006

Purpose: Frequency of sesamoid bone on hallucal interphalangeal joint has been described to be low probability in orthopaedic and anatomical literature. We have, however, experienced two cases of interphalangeal joint dislocation giving difficulty to usual manipulative reduction because of presence of sesamoid bone recently. In order to ascertain existence of sesamoid bone on interphalangeal joint of hallux in Korean adults, radiological study have been performed with feet of patients Materials and Methods: Between May 2003 and October 2006, 974 patients with 1098 radiographs of feet which were reached skeletal maturity over 18-year-old were examined. Unilateral or bilateral anteroposterior, lateral and oblique radiographs were observed by one same person and presence was recorded if there was sesamoid in films. Distance of long and short axes were measured in lateral view and cases of two sesamoids in interphalangeal joint were recorded. Statistical differences between left and right side or between men and women were evaluated by chi-square test. Results: Frequency of sesamoid was 980 cases (89.3%) and no occurrence in 118 cases (10.7%). Two sesamoids were observed in 3 cases. Average distance of long axis was 4.9 mm (range, 0.5-11.4) and average distance of short axis was 3.5 mm (range, 0.3-9.3). Unilateral sesamoid was observed in 7 patients (5.6%), bilateral absence was 7 patients (5.6%) and bilateral sesamoids in 110 patients (88.8%) out of 124 patients who took bilateral feet radiographs. Men has less frequency than women significantly (p=0.014) while there was no significant difference in frequency according to side(p>0.05). Conclusion: Sesamoid bone was seen in 980 feet (89.3%) out of 1098 normal Korean radiological studies of feet. We report 3 cases of two seamoids which was extremely rarely reported in literature. Korean frequency is similar with Japanese, but much higher than Caucasians and black Africans.

• 대한정형외과스포츠의학회:학술대회논문집
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• 2007.04a
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• pp.3-5
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• 2007

• Journal of Korean Orthopaedic Sports Medicine
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• v.1 no.1
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• pp.71-74
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• 2002

Purpose : To evaluate the clinical and radiological characteristics of osteochondral ridges of talus and ankle. Materials and Methods : We have analyzed their clinical symptoms and signs, radiologic and CT findings and post-operative results in 17 ankle joints of 14 patients (bilateral in 3), followed them for average 13 months after surgical excision. Results : No definite trauma, but mostly in male after middle age. Their chief complaints are pain on ankle, especially in dorsiflexion or squatting position, and symptom durations are very long, more than average 15 months. Definite diagnosis was made by lateral radiograms of ankle joint. Osteochondral ridges are common in talar neck (10 cases), tibia (4 cases) and both side (3 cases). After excision of osteophytes, all patients gained normal ankle without pain and any limited motion. Conclusions : Anterior impingement syndromes are common in middle aged male, but no definite correlation with sports. Plantar and dorsiflexed lateral radiographs are helpful in definite diagnosis for impingement, and surgical excision is best for treatment.

• Journal of Life Science
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• v.19 no.5
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• pp.659-663
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• 2009

Bacterial stain 3Y was isolated from a site that was contaminated with diesel for more than 15 years. The strain could grow on various petroleum using hydrocarbons as the sole carbon source. The strain grew not only on aliphatic hydrocarbons but also on aromatic hydrocarbons. 3Y grew on aliphatic petroleum hydrocarbons hexane or hexadecane, and aromatic petroleum hydrocarbons BTEX, phenol, biphenyl, or phenanthrene. The strain showed aromatic ring dioxygenase and meta-cleavage dioxygenase activities as determined by tests using indole and catechol. Aromatic ring dioxygenase is involved in the initial step of biodegradation of aromatic hydrocarbons while meta-cleavage dioxygenase catalyzes the cleavage of the benzene ring. Based on a nucleotide sequence analysis of its 16S rRNA gene, 3Y belongs to the genus Sphingomonas. A phylogenetic tress was constructed based on the nucleotide sequences of closest relatives of 3Y and petroleum hydrocarbon degrading sphingomonads. 3Y was in a cluster that was different from the cluster that contained well-known sphingomonads. The results of this study suggest that 3Y has the potential to cleanup oil-contaminated sites. Further investigation is warranted to optimize conditions to degrade petroleum hydrocarbons by the strain to develop a better bioremediation strategy.

• Bulletin of the Korea Photovoltaic Society
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• v.2 no.2
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• pp.21-28
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• 2016

3족과 5족 물질로 구성된 III-V 고효율 화합물 태양전지는 태양광 스펙트럼에 대한 많은 파장영역대의 빛을 흡수할 수 있는 장점을 갖고 있어 지구상에서 만든 태양전지 중 가장 효율이 높다. 그러나, III-V 화합물 물질은 실리콘 보다 고가의 비용이 들므로 이를 극복하기 위해서 집광렌즈 및 빛을 추적하기 위한 추적기 등 집광시스템으로 구성되어야 한다. 본고에서는 고효율의 III-V 화합물 태양전지의 현재 기술개발동향 및 고효율 저가화를 위한 방안으로 기판재활용 기술, 태양광 태양열 복합활용 시스템 및 소형집광모듈 등을 소개하고자 한다.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.660-663
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• 2005

Aiming the development of novel acid amplifiers, 2-hydroxyphenyl-4-methylbenzenesulfonate (1), 3-hydroxyphenyl-4-methylbenzene sulfonate (2), 4-hydroxyphenyl-4-methylbenzenesulfonate (3) were synthesized as the aromatic acid amplifiers with good thermal stability. They were autocatalytically generated p-toluenesulfonic acid in the presence of small amount of acid evolved from a photoacid generator. These aromatic sulfonates showed excellent thermal stability in PtBMA film and were proven to be the first aromatic acid amplifier to act as a photosensitivity enhancer. When these compounds were coupled with a chemically amplified photoresist system, photosensitivity was enhanced up to 3~6 folds.

• Journal of Korean Foot and Ankle Society
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• v.19 no.4
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• pp.176-180
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• 2015

Purpose: The aim of the current study is to report on the clinical and radiographic results after calcaneo-stop procedure in Korean children with symptomatic flexible flatfoot. Materials and Methods: Twenty-two children suffering pain along the medial aspect of midfoot with flexible flatfoot whose symptoms did not improve with conservative measures and therefore underwent calcaneo-stop procedure were identified retrospectively. Clinically, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale and visual analogue scale (VAS) were evaluated. Radiographically, standing anteroposterior and lateral radiographs of the foot and Saltzman's alignment views were taken and talonavicular coverage angle, lateral talo-first metatarsal angle, and hindfoot alignment angles were measured and analyzed. Results: Clinically, AOFAS ankle-hindfoot scale improved from $70.3{\pm}5.6$ to $97.3{\pm}2.5$ and VAS improved from $6.4{\pm}1.6$ to $0.2{\pm}0.4$. Radiographically, talonavicular coverage angle improved from $28.3^{\circ}{\pm}12.3^{\circ}$ to $10.9^{\circ}{\pm}8.1^{\circ}$, lateral talo-first metatarsal angle improved from $-19.3^{\circ}{\pm}9.0^{\circ}$ to $-2.4^{\circ}{\pm}8.1^{\circ}$, and hindfoot alignment angle improved from valgus $11.9^{\circ}{\pm}10.0^{\circ}$ to $3.5^{\circ}{\pm}4.3^{\circ}$ at minimum 2-year follow-up. No complications occurred postoperatively. Conclusion: Calcaneo-stop procedure is a simple and very effective procedure for management of pediatric symptomatic flexible flatfoot that does not respond to conservative treatment.

• Journal of the Korean Chemical Society
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• v.39 no.4
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• pp.266-274
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• 1995

The extractions of aqueous Eu3+ and Tb3+ ions into ethylacetate or dichloromethane were conducted by using 12-crown-4, 15-crown-5 and 18-crown-6 ethers as ligand. Benzoate ion was selected as counter anion for the complexes formed between the lanthanide ions and crown ethers. Fluorescence spectra of the lanthanide ions induced by the energy transfer from benzoate anion to the cations were also measured. The quantitative analysis of the lanthanide ions extracted into organic phase were made on the basis of the results of fluorescence. The measured extractivity is interpreted in terms of the ion-dipole interaction.

• Archives of Reconstructive Microsurgery
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• v.8 no.1
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• pp.77-83
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• 1999

The skin on the dorsum of the foot is a source of the reliable thin and sensory cutaneous free tissue transplantation with or without tendon, bone and joint. A composite flap with attached vascularized tendon grafts for the combined loss of skin and tendon on the dorsum of the hand and foot offers an immediate one stage solution to this problem. The flap provides a very durable innervated tissue cover for the heel of the foot and the dorsum of the hand and an osteocutaneous transfer combined with the second metatarsal. The major dorsalis pedis artery is constant in size, but the first dorsal metatarsal artery is variable in size and location. The dorsal surface of the foot receives sensory innervation through the superficial peroneal nerve and the first web through the deep peroneal nerve. Authors had performed 5 dorsalis pedis free flap transplantation in the foot and hand at Department of Orthopedic Surgery, Chonbuk National University Hospital from August 1993 through August 1997 and followed up for the period of between 19 and 67 months until March 1999. The results were as follows 1. 5 cases dorsalis pedis free flap transfer to the foot(4 cases) and the hand(1 case) were performed and the recipient was foot dorsum and heel 2 cases each and hand dorsum 1 case. 2 All of 5 cases(100%) were survived from free flap transfer and recipient artery was dorsalis pedis artery(2 cases), anterior tibial artery(1 case), posterior tibial artery(1 case) and ulnar artery(1 case) and recipient veins were 2 in number except in the hand. 3. Long term follow up of the exterior and maceration was good and sensory recovery was poor 4. Donor site was covered with full thickness skin graft obtained from one or both inguinal areas at postoperative 3rd week and skin graft was taken good and no morbidity was showed.