• Journal of Korea Game Society
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• v.11 no.1
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• pp.47-57
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• 2011

Mobile based location-based service can normally be classified into four categories according to their dimensions of their screen layout: map-based, bird-eye view based, photo-based, and video-based. Specifically, video-based layout system combining AR technology has a appealing factor to users through the reality-based presence but normally requires sophisticated real-time image matching algorithms to represent the system. This paper provides a new location-based service by introducing mirror world to resolve the problem and implements its prototype. The proposed service does not need such algorithm and will effectively be useful for users to get the reality of the presence for any locations which is regardless of a user's real location.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.202.1-202.1
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• 2014

최근 대용량 에너지 저장장치로 사용하고자 하는 리튬-공기전지는 리튬 음극과 액체 전해질 사이의 화학적 불안정성이 문제가 되고 있다. 또한 리튬이온전지는 액체전해질의 사용으로 인해 폭발 등의 안정성 문제가 대두되고 있는 실정이다. 때문에 리튬-공기전지에서 리튬 음극을 액체 전해질로부터 보호할 수 있으며, 리튬이온전지의 액체전해질과 대체하였을 때 전극과도 안정한 고체전해질의 연구가 필요하다. 고체전해질은 구조적으로 crystalline, glassy, 폴리머로 나눌 수 있는데, 이 중 crystalline 구조의 고체전해질은 glassy 및 폴리머 고체전해질에 비해 상온에서 비교적 이온전도도가 높다고 알려져 있다 [1]. 그러나 이온전도도가 높은 황화물 및 질화물 고체전해질은 수분에 민감한 반면 [2,3], 산화물 계열의 물질은 안정할 것으로 예상된다. 본 연구에서는 이온전도도가 높은 산화물인 lithium lanthanum titanate ($Li_{0.5}La_{0.5}TiO_3$, LLTO)를 고체전해질로 선정하여 다양한 환경에서 화학적 안정성에 관해 연구하였다. LLTO와 각종 용액과의 화학적 안정성을 살펴보기 위해 고체전해질을 DI water, 1 M $LiPF_6$ Ethylene Carbonate (EC)-Dimethyl Carbonate (DMC) (50:50 vol.%), 0.57 M LiOH (pH=13), 0.1 M HCl (pH=1)에 immersion하고 무게, 표면형상, 상(phase), 이온전도도 등의 변화를 관찰하였다. 또한 LLTO와 전극간의 반응성을 알아보기 위해 LLTO 분말과 음극물질인 $Li_4Ti_5O_{12}$ 및 양극물질인 $LiCoO_2$ 분말을 혼합한 후 $300^{\circ}C{\sim}700^{\circ}C$의 온도범위에서 열처리하여 반응을 가속화 한 후 상변화 현상을 살펴보았다.

• Journal of Korean Physical Therapy Science
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• v.13 no.2
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• pp.37-45
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• 2006

The purpose of this study was to determine the effect of treadmill training on gait, balance, and trunk control in a patient with hemiparesis. A female subject who had suffered a left hemiparesis 12 months previously was selected for this study. A single subject ABA design was used. Eight data-collection sessions were conducted during each of three phases (baseline-intervention-withdrawal). During baseline and withdrawal phases, the treatment based on Bobath approach was performed for the subject, and during the intervention phase, treadmill walking training was added. Assessment tools were made using the 10 m walk test, Rivermead Visual Gait Assessment(RVGA), Berg Balance Scale(BBS), and a seated Lateral Reach Test(LRT). During the intervention phase, the time measured in 10 m walk test and the scores of RVGA and BBS were significantly improved, and the number of steps in 10 m walk test and LRT showed a small improvement. During withdrawal phase, the time measured in 10 m walk test and the scores of RVGA and BBS were shown the carry-over effect. This findings indicate that treadmill training has significant effect to gait function and balance in a patient with chronic hemiparesis.

• Journal of Society of Preventive Korean Medicine
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• v.9 no.1
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• pp.119-133
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• 2005

Traditional herbal medicine is widely used among the Korean people, and other eastern Asian countries employ similar therapies as well. In recent years, due to increasing interest in herbal medicines, many researches have been made on the toxicity and side effects of herbal medications. Through private and public media, there have been many opinions suggesting taking herbal medicines is very harmful, especially on the liver and kidney functions. This assertion has been mainly presented by the doctors that practice western medicine, But this assertion is never based on adequate knowledge of herbal medicine. This study aims to provide the evidences that taking herbal medicines is safe on the renal functions. Four frequently used herbal medications(Sipjeondaebotang, Bojungigitang, Ojeoksan, and Yukmijihwangtang) were used to test the toxicity of herbal medicine oh the lab animal model(SD-Rat). There is no significant difference in body weight and kidney weight after herbal medication for 1 month. In all experimental groups, no abnormal findings were observed in histological study, and lab renal function index(BUN, creatinine, uric acid). These results say that four herbal multi-used-medicines, when medicated, is safe from the renal toxicity in lab animal model.

• The Journal of Korean Physical Therapy
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• v.16 no.4
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• pp.168-178
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• 2004

The purposes of this paper were to investigate the effect of active treatment compared with a conservative treatment and to provide the information for physical therapy in patients suffering from chronic neck pain. Forty female subjects who were diagnosed with cervical radiculopathy participated in this study and were divided into the conservative and active treatment groups. The active treatment group consisted of 20 patients who were treated with therapeutic modalities and active neck exercise program during the admission (15 days) and one month after discharge. The conservative treatment group consisted of 20 patients who were not received with active neck exercise program. The assessment tools were made using visual analogue scale(VAS), neck disability index(NDI) and modified Zung depression scale(MZDS). All subjects were measured three times: before the admission, at discharge, and at one month after discharge. Data were compared by groups using independent t-test. VAS, NDI and MZDS scores measured at admission and discharge were not significantly different between the groups. On the assessment performed one month after discharge, VAS and NDI scores were significantly lower for the active treatment group compared with those of the conservative treatment group(p<0.05), but MZDS score was not significantly different between the groups. In the comparison of two treatment methods for chronic neck pain, active treatment was more effective than conservative treatment. The findings of the study indicate that active treatment in chronic neck pain has a positive effect in relieving pain and restoring neck function.

• Physical Therapy Korea
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• v.17 no.3
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• pp.31-39
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• 2010

The purpose of this study was to determine the effect of sciatic nerve mobilization technique on perceived pain, straight leg raise test (SLR), and strength of knee extensor, location of symptoms (LOS) in patients with chronic low back pain. 22 patients with chronic low back pain were recruited for this study. The subjects were randomly assigned to either the experimental group (EG) or the control group (CG), with 11 patients in each group. All patients received a routine physical therapy (hot pack and transcutaneous electrical nerve stimulation). The mobilization technique of the sciatic nerve was performed for 10 min in the case of the EG subjects. Outcome measurements included the level of the perceived pain, SLR, and strength of the knee extensor, LOS. The measurements were recorded 3 times: before the intervention, after the intervention, and at 1 hour of follow up. The two groups did not significantly differ with regard to the level of perceived pain, SLR, and strength of the knee extensor, LOS before the test (p>.05). In the case of the EG subjects, all the variables measured after the intervention significantly differed from those measured before the intervention (p<.05). However, in the case of the CG subjects, a significant difference was noted only with regard to the level of perceived pain (p<.05). The findings indicate that sciatic nerve mobilization technique exerts a positive effect on the control of subjective symptoms and knee strength in patients with chronic low back pain. Further studies are required to generalize the result of this study.

• Journal of the Korean Ceramic Society
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• v.39 no.12
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• pp.1133-1137
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• 2002

The cement for solidification of the toxic waste was fabricated using a mixture of the waste concrete powder and blast furnace slag in the ratio of 1:1 and its hydrate morphology and compressive strength of the sample were evaluated in order to apply to the solidification of the COREX sludge. The X-ray diffraction analysis of the sample which prepared by the addition of 10% Portland cement and hemihydrate showed the presence of $Ca(OH)_2$, ettringite, gel-phase and C-S-H hydrate. Compressive strength of the sample exhibited enough high to use as a solidification cement. The strength of the sample was over 140 kgf/$m^2$ in 7 days in case of solidification of the COREX sludge and the sample possess sufficient morphology for the solidification and stabilization of the waste sludge.

• Korean Journal of Materials Research
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• v.20 no.10
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• pp.535-542
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• 2010

In this study, we used coal-based activated carbons and charcoal as startingmaterials, phenolic resin (PR) as a binder, and TOS as a titanium source to prepare $TiO_2$ combining spherical shaped activated carbon photocatalysts. The textural properties of the activated carbon photocatalysts (SACP) were characterized by specific surface area (BET), energy dispersive X-ray spectroscopy (XRD), scanning electron microscopy (SEM), iodine adsorption, strength intensity, and pressure drop. The photocatalytic activities of the SACPs were characterized by degradation of the organic dyes Methylene Blue (MB), Methylene Orange (MO), and Rhodamine B (Rh. B) and a chemical oxygen demand (COD) experiment. The surface properties are shown by SEM. The XRD patterns of the composites showed that the SACP composite contained a typical single, clear anatase phase. The EDX spectro for the elemental indentification showed the presence of C and O with Ti peaks. According to the results, the spherical activated carbon photocatalysts sample of AOP prepared with activated carbon formed the best spherical shape, a high BET surface area, iodine adsorption capability and strength value, and the lowest pressure drop, and the photocatalytic activity was better than samples prepared with charcoal. We compared the degradation effects among three kinds of dyes. MB solution degraded with the SACP is better than any other dye solutions.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.46 no.6
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• pp.78-87
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• 2009

In this paper, we propose a new method of blocky artifacts measurement for IP based video service. In order to assess the quality of IP based video service, we classify degradation into blocking artifacts by network error or by transmission error. in order to assess blocking artifacts based on No-reference, we estimate blocky artifacts from network errors and image compression by calculating amount of difference between target block and neighbor blocks and error concealment algorithm in a video receiver. To ensure accuracy of proposed method, we compare our result to MOS data using SSCQE method. Experimental results show that the proposed algorithm is better than a conventional method by around 1.3.

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.2002-2010
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• 2006

This study examined the quenching of ofloxacin (OFL) and flumequine (FLU) fluorescence by $Cuj^{2+}$, $Ni^{2+}$, $Co^{2+}$ and $Mn^{2+}$ in an aqueous solution. The change in the fluorescence intensity and lifetime was measured at various temperatures as a function of the quencher concentration. According to the Stern-Volmer plots, the fluorescence emission was quenched by both collisions (dynamic quenching) and complex formation (static quenching) with the same quencher but the effect of static quenching was larger than that of dynamic quenching. Large static and dynamic quenching constants for both OFL and FLU support significant ion-dipole and orbital-orbital interactions between fluorophore and quencher. For both molecules, the static and dynamic quenching constants by $Cu^{2+}$ were the largest among all the metal quenchers examined in this study. In addition, both the static and dynamic quenching mechanisms by $Cu^{2+}$ were somewhat different from the quenching caused by other metals. Between $Ni^{2+}$ and FLU, a different form of chemical interaction was observed compared with the interaction by other metals. The change in the absorption spectra as a result of the addition of a quencher provided information on static quenching. With all these metals, the static quenching constant of FLU was larger than those of OFL. The fluorescence of OFL was quite insensitive to both the dynamic and static quenching compared with FLU. This property of OFL can be explained by the twisted intramolecular charge transfer in the excited state.