• Title/Summary/Keyword: STABILITY

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EEG response of tea tree oil fragrance for the development of functional shampoo additives (기능성 샴푸첨가제 개발을 위한 티트리 오일 향의 뇌파 반응)

  • Ryeng Kim;Min-Seok Oh;Young-Ho Lee;Seong-Ho Choi;In-Kyoung Kim
    • Journal of Advanced Technology Convergence
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    • v.2 no.1
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    • pp.23-31
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    • 2023
  • This study was described about the EEG response results of tea tree oil fragrance for the development of functional shampoo additives. In the case of experimenters (1) the intensity change of the right brain alpha wave in electroencephalographic (EEG) response was increased after inhalation of the tea tree oil fragrance. (2) the change of physical tension and stress both the left brain and the right brain in EEG response showed a tendency to decrease after inhalation compared to before inhalation of the tea tree fragrance. (3) the mental distraction and stress was decreased after experimenters inhales the tea tree oil fragrances. These means the tea tree fragrances have both mental stability and stress relief. From above results, we prepared the functional shampoo additives with tea tree oil, and the we determined the alpha wave in EEG response after the functional shampoo additive fragrance for experimenters. As results, (4) the alpha wave intensity in left and right brain was significantly decreased after inhaling the functional shampoo additives fragrance. (5) physical tension and stress changes were decreased after inhalation of functional shampoo additive fragrance. (6) mental distraction and stress changes were also decreased after inhalation of functional shampoo additive fragrance. , From above results, the functional shampoo additives could be used as physical and mental relievers. Furthermore, the functional shampoo additives have the effects of scalp calming when the experimenter was treated shampoo with the functional shampoo additives.

A Study on Pullout-Resistance Increase in Soil Nailing due to Pressurized Grouting (가압 그라우팅 쏘일네일링의 인발저항력 증가 원인에 관한 연구)

  • Jeong, Kyeong-Han;Park, Sung-Won;Choi, Hang-Seok;Lee, Chung-Won;Lee, In-Mo
    • Journal of the Korean Geotechnical Society
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    • v.24 no.4
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    • pp.101-114
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    • 2008
  • Pressurized grouting is a common technique in geotechnical engineering applications to increase the stiffness and strength of the ground mass and to fill boreholes or void space in a tunnel lining and so on. Recently, the pressurized grouting has been applied to a soil-nailing system which is widely used to improve slope stability. Because interaction between pressurized grouting paste and adjacent ground mass is complicated and difficult to analyze, the soil-nailing design has been empirically performed in most geotechnical applications. The purpose of this study is to analyze the ground behavior induced by pressurized grouting paste with the aid of laboratory model tests. The laboratory tests are carried out for four kinds of granitic residual soils. When injecting pressure is applied to grout, the pressure measured in the adjacent ground initially increases for a while, which behaves in the way of the membrane model. With the lapse of time, the pressure in the adjacent ground decreases down to a value of residual stress because a portion of water in the grouting paste seeps into the adjacent ground. The seepage can be indicated by the fact that the ratio of water/cement in the grouting paste has decreased from a initial value of 50% to around 30% during the test. The reduction of the W/C ratio should cause to harden the grouting paste and increase the stiffness of it, which restricts the rebound of out-moved ground into the original position, and thus increase the in-situ stress by approximately 20% of the injecting pressures. The measured radial deformation of the ground under pressure is in good agreement with the expansion of a cylindrical cavity estimated by the cavity expansion theory. In-situ test revealed that the pullout resistance of a soil nailing with pressurized grouting is about 36% larger than that with regular grouting, caused by grout radius increase, residual stress effect, and/or roughness increase.

A Survey of Patient Satisfaction with the use of Aloe Vera Mist for Skin Care during Radiation Therapy for Breast Cancer (유방암 방사선치료 중 피부 관리를 위한 알로에 베라 미스트 사용에 대한 환자 만족도 조사)

  • Han-A Yun;Hyo-Young Lee
    • Journal of the Korean Society of Radiology
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    • v.17 no.2
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    • pp.231-242
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    • 2023
  • This study aims to provide basic data to reduce the incidence of radiation dermatitis and improve patient satisfaction by investigating the management status and satisfaction level of radiation dermatitis in patients undergoing radiation therapy. From October 28, 2022, to April 4, 2023, a survey was conducted on 137 breast cancer patients who received radiation therapy at G Hospital in Busan. The Radiation Therapy Oncology Group (RTOG) cutaneous acute radiotherapy toxicity score was used as the standard for measuring skin reactions, and the association between cancer stage and RTOG was analyzed. SPSS program (ver. 18.0) was used for statistical analysis. The frequency of radiation dermatitis occurrence was relatively low, with 73% in the RTOG 0-1 group and 27% in the 2-3 group. Patient satisfaction after radiation therapy varied significantly depending on the RTOG group, with lower levels of dermatitis resulting in higher satisfaction and higher levels resulting in dissatisfaction (p=0.001). Although there was no statistically significant difference in RTOG group and skin satisfaction depending on the frequency of aloe mist use (p=0.065), the group that used it 1-2 times a day (69.3%) showed a higher satisfaction level. The perceived effects of aloe mist use were statistically significant for decreasing heat sensation (p=0.001), pain (p=0.033), itching (p=0.001), and psychological stability (p=0.027), especially in the higher RTOG groups. Additionally, as cancer stage increased, the severity of radiation dermatitis also increased, which was statistically significant (p=0.001). In conclusion, radiation dermatitis is the most common side effect of radiation therapy, and it can appear in various forms depending on individual skin sensitivity and external factors during treatment. Adequate education before treatment and the use of MD Cream and aloe vera mist are recommended to reduce the incidence and manage radiation dermatitis effectively.

Re-review of the Structure of the Jeongsa-Kisun (Senior Envoy Ship) in the Joseon Dynasty from the Perspective of Professional Shipbuilding Engineering (조선통신사 정사 기선(騎船) 구조의 조선기술 연구)

  • HONG Sunjae
    • Korean Journal of Heritage: History & Science
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    • v.55 no.4
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    • pp.242-275
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    • 2022
  • This study tries to reveal the structure of the "Kisun"(senior envoy ship) taken by senior envoys for the 10th to 12th visits to Japan from the perspective of professional shipbuilding engineering focusing on the theory of the ship in the travel logs of royal envoys to Japan (Sahaengrok) written by Joseon Tongsinsa that includes 12 visits to Japan for about 200 years from 1607 to 1811. The results of the study showed that the size of Kisun for the 10th to 12th envoy visits was 19 Pa (把) and a half in length and 6 Pa (把) and 2 Cheok (尺) in width. The height of the Sampan was found to be 2 Pa (把) and 1 Cheok (尺) based on records in Gyemisusarok and Jeungjeonggyorinji. The structure of Kisun was different for each visit but, it was found that Kisun was mainly composed of a main deck, bow (bow plate, stem plate), stern (stern plate), Sampan, Meonge (support), Garyong (support), Sinbang, Gungji, deck, two masts and sail, Gurejjak (mast support), Panok, stern Panok, Taru, dodger, anchor reel, stairs, rail, rudder, oar, and anchor. In addition, wood and iron nails were used together for connection. It was also found that the sail was made of herbage and cotton. This study found that Kisun, which was operated for the 10th and 12th envoy visits, was big in terms of length and height among the Joseon Tongsinsa fleet to show the authority and dignity of Joseon and that it had passages outside on the sides of the vessel and paddles were located between the sides and Panok structure and rails were installed on four sides on the Panok, improving stability and linear beauty. The walls of Panok were decorated with the royal Dancheong pattern and fancy murals. In addition, it was found that they wished for a safe voyage by drawing a demon face on the bow. Therefore, it was revealed that Kisun, which was taken by envoys as recorded in travel logs, was made by the state and equipped with structures and functions that enabled international voyages.

Stress Variation Characteristics of Temporary Fixed Steel Rod in FCM Bridge Construction Method (FCM 교량 가설 공법에서 임시 고정 강봉의 응력 변화 특성 )

  • Hyun-Euk Kang;Wan-Shin Park;Young-Il Jang;Sun-Woo Kim;Hyun-Do Yun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.3
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    • pp.21-29
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    • 2023
  • In this study, the stress characteristics of temporary fixed steel rods were analyzed in the "temporary fixing system using internal prestressing tension", which is mainly applied to the construction of superstructures by FCM. It was difficult to confirm the changes in initial tensile force in this system because the steel rod was internally connected to the pier and the PSC BOX. Therefore, measurement was performed before and after the completion of each segment using an FBG sensor to measure the change in the micro length of the steel rod. The results of the analysis showed that 75% to 90% of the maximum vertical contraction of the steel rod that occurred until the completion of the cantilever segment occurred in the fixing ~ 1segment, and the maximum loss of initial prestressing force was 39%. Such excessive loss of tension force to 1 segment means that tension is needed to improve the precision of construction during the fixation, and re-tension is needed to secure stability for conduction of cantilever segments after the completion of 1segment. In the 2 ~ last segment, the stress of the steel rod decreased gradually, and in the summer, the decrease in stress tended to partially recover due to the increase in the length of the steel rod corresponding to the increase in the vertical volume of PSC BOX. The dominant factor in the stress change in 2~ last segment in this phenomenon is judged to be the change in the length of the steel rod according to the temperature. Unlike the change in length, the relaxation was 1.2-2.7%, which was mostly offset by the opposite stress corresponding to the temperature stress. Therefore, a plan was proposed to improve the internal stress, such as adjusting the fixation time.

Clinical Results of Footprint Restoration Anterior Cruciate Ligament Reconstruction with Remnant Preservation (잔여부 보존술식을 이용한 고유부착부 재현 전방십자인대 재건술의 임상결과)

  • Chung, Hyun-Min;Seo, Young-Jin;Song, Si Young;Cha, Myoungsoo
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.6
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    • pp.537-546
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    • 2019
  • Purpose: Anteromedial (AM), posterolateral (PL), anterior, and posterior remnant preserving anterior cruciate ligament (ACL) reconstructions were conducted on patients with partial ACL tears based on the arthroscopic findings. The clinical results of the four groups were compared. Materials and Methods: This study included 98 patients who underwent a remnant preserving ACL reconstruction from January 2013 to June 2016 and could be followed-up for at least two years. The subjects were categorized into four groups according to the selective bundles reconstructed: group A, anteromedial selective bundle reconstruction; group B, posterolateral selective bundle reconstruction; group C, anterior bundle reconstruction; and group D, posterior bundle reconstruction. The preoperative and postoperative anterior translation from the stress X-ray, International Knee Documentation Committee Subjective Knee Form (IKDC SKF) score, Lysholm score, and hospital for special surgery (HSS) score were compared. Results: All four groups showed significant improvement in anterior translation on the stress X-ray conducted with knees at 15° flexion, IKDC SKF score, Lysholm score, and HSS score postoperatively (in all groups, p<0.001). No intergroup differences were observed in terms of the functional outcomes except that preoperative IKDC SKF score was higher in the C group than in the A group (p=0.021), and the preoperative Lysholm score was higher in the B group than in the A group (p=0.03). Conclusion: After the AM, PL, anterior, and posterior remnant preserving ACL reconstructions, all four groups showed satisfactory results in terms of the anteroposterior stability and functional knee scores with no significant intergroup differences.

Aspects of Emotional Customs by the N-po Generation (N포세대의 감정 풍속도)

  • Seo, Yeon-Ju
    • Journal of Popular Narrative
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    • v.25 no.1
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    • pp.55-85
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    • 2019
  • In this article, we examine the real meaning behind the stories in which the N-po Generation (Millennial Generation) is depicted, through the observation of entertainment programs, TV series, and movies. This could be an opportunity to investigate the aspects of emotional customs of our era, which have been described by television media as portraying the complex and multifaceted reality in the most mundane and popular manner while influencing the public. Problems with youth unemployment, the polarization of life, and instability are not only global issues but situations that specifically occur in South Korea. It is thus vital to pay attention to the inner side of the N-po Generation who enjoy Sohwakhaeng (small but certain happiness) by eating alone as the placebo effect of this tough reality. This is an agenda that should be viewed as a problem in the fundamental design of South Korean society. The consciousness of the problem shown in the TV series has been drawing attention. The TV series Because depicts a love narrative that concentrates on emotions in a relationship that started between housemates due to poverty and housing problems, leading to marriage. Thus, the TV series persuasively dramatized 'confluent love' in the N-po Generation. In the movie , Miso can be regarded as a symbol that represents the emergence of a new generation of cultural sensitivity. There is a suggestion in the sequence of that identifies the pursuit of taste with the discovery of identity. The TV series is a growth narrative that deals heavily with youth unemployment, temporary workers, fragmented families, and dating violence. The housemates in find emotional stability through interaction with each other, and courageously approach their individual problems. In the process, images of women, who are empathetic towards others and are willing to jointly solve their problems, are calmly depicted to reveal a story of growth revolving around a ground emotional community. The current problem that South Korean society should contemplate is how to be fully human beyond mere survival, and how to further seek the conditions of human existence. In that sense, what we should pursue is a notion of 'publicness', which can put several generations together. Because of the reality that confliction between generations must be triggered, in order to make a passage of sympathizing, mass media's sensitivity training becomes more important. This may be the duty of mass media.

Research on Radiation Shielding Film for Replacement of Lead(Pb) through Roll-to-Roll Sputtering Deposition (롤투롤 스퍼터링 증착을 통한 납(Pb) 대체용 방사선 차폐필름 개발)

  • Sung-Hun Kim;Jung-Sup Byun;Young-Bin Ji
    • Journal of the Korean Society of Radiology
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    • v.17 no.3
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    • pp.441-447
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    • 2023
  • Lead(Pb), which is currently mainly used for shielding purposes in the medical radiation, has excellent radiation shielding functions, but is continuously exposed to radiation directly or indirectly due to the harmfulness of lead itself to the human body and the inconvenience caused by its heavy weight. Research on shielding materials that are human-friendly, lightweight, and convenient to use that can block risks and replace lead is continuously being conducted. In this study, based on the commonly used polyethylene terephthalate (PET) film and the fabric material used in actual radiation protective clothing, a multi-layer thin film was realized through sputtering and vacuum deposition of bismuth, tungsten, and tin, which are metal materials that can shield radiation. Thus, a shielding film was produced and its applicability as a radiation shielding material was evaluated. The radiation shielding film was manufactured by establishing the optimized conditions for each shielding material while controlling the applied voltage, roll driving speed, and gas supply amount to manufacture the shielding film. The adhesion between the parent material and the shielding metal thin film was confirmed by Cross-cut 100/100, and the stability of the thin film was confirmed through a hot water test for 1 hour to measure the change of the thin film over time. The shielding performance of the finally realized shielding film was measured by the Korea association for radiation application (KARA), and the test conditions (inverse wide beam, tube voltage 50 kV, half layer 1.828 mmAl) were set to obtain an attenuation ratio of 16.4 (initial value 0.300 mGy/s, measured value 0.018 mGy/s) and damping ratio 4.31 (initial value 0.300 mGy/s, measured value 0.069 mGy/s) were obtained. by securing process efficiency for future commercialization, light and shielding films and fabrics were used to lay the foundation for the application of films to radiation protective clothing or construction materials with shielding functions.

A Study of Physicochemical Characteristics and Adsorption properties of Cs and Sr of Natural Zeolite from Kuryongpo in Korea (한국 구룡포산 천연 제올라이트의 이화학적 특성 및 Cs과 Sr 흡착 특성 연구)

  • Bayarsaikhan Battsetseg;Hu Sik Kim;Hyeon Uk Choo;Jong Sam Park;Woo Taik Lim
    • Korean Journal of Mineralogy and Petrology
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    • v.36 no.2
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    • pp.117-124
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    • 2023
  • X-ray diffraction analysis, X-ray fluorescence analysis, thermal differential and thermos gravimetric analysis, cation exchange capacity analysis, and Cesium (Cs), Strontium (Sr) adsorption experiments were performed to investigate the physical and chemical properties of natural zeolite from Guryongpo in Korea. As a result of X-ray diffraction analysis, minerals such as mordenite, heulandite, clinoptilolite, and illite are contained, and as a result of X-ray fluorescence analysis, elements such as SiO2, Al2O3, CaO, K2O, MgO, Fe2O3 and Na2O are contained, and the cation exchange capacity was 148.6 meq/100 g. As a result of thermal differential and thermos gravimetric analysis, it was confirmed that the thermal stability was excellent up to 600 ℃. As a result of the adsorption equilibrium experiment over time, the equilibrium was reached within 30 min. for Cesium (Cs) and within 8 hr. for Strontium (Sr), and the adsorption rates of Cesium (Cs) and Strontium (Sr) were 80% and 18%, respectively. As a result of the single-component isothermal adsorption experiment, in conformed to the Langmuir model, and the maximum Cesium (Cs) adsorption amount was 131.5 mg/g, which was high, while the Strontium (Sr) maximum adsorption amount was 29.5 mg/g, which was low. In the case of the natural zeolite used in this study, the content of minerals including 8-rings such as clinoptilolite, heulandite, and mordenite is high, showing high selectivity for Cesium (Cs).

Manufacturing Method and Characteristics of the Dongrok(copper chloride) pigments (동록(염화동) 안료의 제조방법 및 특성에 관한 연구)

  • KANG Yeongseok;PARK Juhyun;MUN Seongwoo;HWANG Gahyun;KIM Myoungnam;LEE Sunmyung
    • Korean Journal of Heritage: History & Science
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    • v.56 no.2
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    • pp.148-169
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    • 2023
  • Hayeob pigment is known as one of the traditional dark green pigments, but the color, raw material, and manufacturing method have not been clearly identified. However, comparing the analysis results of the particle shape and constituent minerals of Hayeob pigments revealed through pigment analysis studies of colored cultural properties such as Dancheong, Gwaebul, and paintings, Hayeob pigments appear to be the same as Dongrok pigments produced by salt corrosion. Therefore, in order to restore Hayeob pigment, the manufacturing method of Dongrok pigment was studied based on the records of old literature. The Dongrok pigment manufacturing method confirmed in the old literature records is a natural corrosion method in which copper powder and a caustic are mixed and then left in a humid condition to corrode. Based on this, artificial corrosion using a corrosion tester was adopted to corrode the copper powder more efficiently, and an appropriate mixing ratio was selected by analyzing the state of corrosion products according to the mixing ratio of the caustic agent. In addition, the manufacturing method of Dongrok pigment was established by adding a salt removal process to remove residual caustic agents and a purification process to increase chroma during pigment coloring. The prepared Dongrok pigments have a bluish green or green color, show an elliptical particle shape and a form in which small particles are aggregated, and a porous surface is observed. The main constituent elements are copper(Cu) and chlorine(Cl), and the main constituent mineral is identified as atacamite [Cu2Cl(OH)3]. As a result of an accelerated weathering test to evaluate the stability of the prepared Dongrok pigments, it was found that the greenness partially decreased and the yellowness significantly increased as deterioration progressed. Before deterioration, the Dongrok pigments had lower yellowness compared to the Hayeob pigments of the old Dancheong, but after deterioration, yellowness increased significantly, and it was found to have a similar chromaticity range as Dancheong's Hayeob pigments. As a result, the prepared Dongrok pigments were confirmed to be similar to Dancheong's Hayeob pigments in terms of color as well as particle shape and constituent minerals.