• Geomechanics and Engineering
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• 제28권3호
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• pp.265-281
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• 2022

A set of slurry shield test system capable of cutter cutting and slurry automatic circulation is used to investigate the deformation characteristics, the evolution characteristics of support resistance and the distribution and evolution process of earth pressure during excavating and collapsing of slurry shield tunneling in circular-gravel layer. The influence of cover-span ratio on surface subsidence, support resistance and failure mode of excavation face is also discussed. Three-dimensional numerical calculations are performed to verify the reliability of the test results. The results show that, with the decrease of the supporting force of the excavation face, the surface subsidence goes through four stages: insensitivity, slow growth, rapid growth and stability. The influence of shield excavation on the axial earth pressure of the front soil is greater than that of the vertical earth pressure. When the support resistance of the excavation face decreases to the critical value, the soil in front of the excavation face collapses. The shape of the collapse is similar to that of a bucket. The ultimate support resistance increase with the increase of the cover-span ratio, however, the angle between the bottom of the collapsed body and the direction of the tunnel excavation axis when the excavation face is damaged increase first and then becomes stable. The surface settlement value and the range of settlement trough decrease with the increase of cover-span ratio. The numerical results are basically consistent with the model test results.

• 한국기계가공학회지
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• 제21권4호
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• pp.60-69
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• 2022

To keep pace with Industry 4.0, it is imperative for companies to redesign their working environments by adopting robotic automation systems. Automation lines are facilitating the latest cutting-edge technologies, such as 3D vision and industrial robots, to outdo competitors by reducing costs. Considering the nature of the manufacturing industry, a time-saving workflow and smooth linkwork between processes is vital. At Dellics, without any additional new installation in the automation lines, only a few improvements to the working process could raise productivity. Three requirements are the development of gripping technology by utilizing a 3D vision system for the recognition of the material shape and location, research on lighting projectors to target long distances and high illumination, and testing of algorithms/software to improve measurement accuracy and identify products. With some of the functional requisites mentioned above, improved robotic automation systems should provide an improved working environment to maximize overall production efficiency. In this article, the ways in which such a system can become the groundwork for establishing an unmanned working infrastructure are discussed.

• 한국수소및신에너지학회논문집
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• 제33권6호
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• pp.776-785
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• 2022

Hydrogen combustion in modern gas-turbine engine is the cutting edge technology as carbon-free energy conversion system. Flashback of hydrogen flame, however, is inevitable and critical specially for premixed hydrogen combustion. Therefore, this experimental investigation is conducted to understand flashback phenomenon in premixed hydrogen combustion. In order to investigate flashback characteristics in premixed hydrogen (H₂)/air flame, we focus on pressure conditions and nozzle shapes. In general, quenching distance reduces as pressure of combustion chamber increases, causing flashback from boundary layer near wall. The flashback regime for reference and modified candidate configurations can broadly appear with increasing combustion chamber pressure. The later one can improve flashback-resist by compensating flow velocity at wall. Also, improved wall flow velocity profile of suggested contraction nozzle prevents entire flashback but causes local flashback at nozzle exit.

• 한국과학예술포럼
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• 제25권
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• pp.379-388
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• 2016

인체연속절단 영상은 관상면, 시상면 영상으로 재구성할 경우 절단무늬가 발생한다. 이러한 문제는 FFT(Fast Fourier Transform)와 놋치필터를 이용하여 제거할 수 있었지만 놋치필터의 사용으로 급격한 주파수 변화에 따른 파문현상의 발생은 여전히 문제로 남아 있다. 따라서 본 연구는 놋치필터의 다양한 형태와 효과를 알아보고 인체연속절단면 영상에 적합한 놋치필터 설계를 제안하고자 한다. 연구의 결과는 다음과 같다. 첫째, 방사형-놋치필터를 사용할 경우 상대적으로 절단무늬를 자연스럽게 보정할 수 있다. 둘째, 방사형-놋치 필터를 사용으로 파문현상이 상대적으로 줄어들었다. 향후 이러한 연구 결과와 더욱 진전된 후속 연구를 통해 파문현상을 완전히 제거하고, 실제 인체 정보에 근접한 데이터를 재현할 수 있을 것으로 기대한다.

• 한국의류학회지
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• 제48권2호
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• pp.312-327
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• 2024

In this study, a rehabilitation 3D printed wearable device was developed by combining an assembly-type robot hand and an integral-type robot hand through fused deposition 3D printing manufacturing with various hardness TPU (Thermoplastic Polyurethane) filaments. The hardware configuration of the robot hand includes a controller designed with four motors, one small servo motor, and a circuit board. In the case of the assembly-type robot hand model, a 3D printed robot hand was assembled using samples printed with TPU of hardness 87A and 95A. It was observed that TPU with a hardness of 95A was suitable for use due to shape stability. For the integrated-type robot hand model, the external sample using TPU of hardness 95A could be modified through a cutting method, and the hardware configuration is the same as the assembly-type. The system structure of the 3D printed robot hand was improved from an individual control method to a simultaneous transmission method.Furthermore, the system architecture of an integrated 3D printed robotic hand rehabilitation device and the application of the rehabilitation device were developed.

• 한국한의학연구원논문집
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• 제12권3호통권18호
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• pp.101-115
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• 2006

The purpose of this study was to introduce the differential standard of the types of Angelicae Pubescentis Radix. We established the classificatory standard according to the external and internal morphology and the physicochemistrical pattern for the four types of Aucklandiae Radix. The results follow: 1. At the external shape, Angelica pubescens f. biserrata has rising lenticel and dark brown surface, Its section is light gray and its xylem is yellow gray. Aralia continentalis has big stem mark in upper portion, its section has no dense tissue with yellow gray. Heracleum hemsleyanum has dark brown surface and little lenticel, its cortical layer is white yellow and xylem is isabella and powdered. 2. At the internal shape, Angelica pubescens f. biserrata has phloem with half of the root and rare vessel. Aralia continentalis has phloem with two-thirds of the root and it has broad cutting and putting vessel that formed 1-2 row. Heracleum hemsleyanum also has phloem with half of the root and wide scattered latex tube and many large vessel. 3. At the TLC pattern, Heracleum hemsleyanum has remarkable dark spot at $R_{f}$ 0.23 on the sulphuric acid color pattern test, but others have faint. 4. At the HPLC pattern, all samples have generally patterns. But Angelica pubescens f. biserrata shows diminutive continentalic acid content and the peak at Rt 20.278min comes out on Heracleum hemsleyanum, but do not come out on Aralia continentalis and Angelica pubescens f. biserrata. Heracleum hemsleyanum has remarkable peak at Rt 20.278min, but shows no peak at Rt 29.023min unlike Aralia continentalis or Angelica pubescens f. biserrata. Also Aralia continentalis and Angelica pubescens f. biserrata show one remarkable peak at Rt 29.023, but Heracleum hemsleyanum do not show. Consequently, Aralia continentalis and Angelica pubescens f. biserrata are comparable whit continentalic acid content and Heracleum hemsleyanum is comparable with the peak at Rt 20.273 and Rt 29.023. So it is thought that content of continentalic acid and the peaks at Rt 20.278 and Rt 29.023 can apply to differentiate a species from other. It is considered the results of this study will be furnished the basis to succeeding studies and it is needed to extensive comparative study for the same genus-degree of relatedness.

• 대한기계학회논문집A
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• 제35권10호
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• pp.1307-1313
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• 2011

전자제어식 차동제한 장치는 기계식에 비해서 능동제어가 가능하고 응답성이 좋아 기계식을 대체해 나가고 있다. STS 304 재질의 코일 하우징은 전자제어식 차동제한장치의 솔레노이드 어셈블리에서 가장 중요한 부품이다. 코일 하우징의 제조시 높은 형상 정밀도가 필수적이나, STS 304의 박판 사용과 가공변수의 변동으로 정밀 가공이 어렵다. 본 연구의 목적은 코일하우징의 가공조건에서 강건해를 구하여 평균과 변동을 최적화 하는 것이다. 코일하우징의 형상정밀도 평균과 표준편차를 최소화 하기 위한 주요 변수로 조의 척킹압력, 절삭속도, 이송속도의 평균과 표준편차가 고려됐다. 가공변수의 변동을 고려하여 평균과 표준편차를 모두 최소화 하는 최적의 조건을 선정하고자 반응표면모델 기반 2차 테일러 전개를 통한 강건 최적설계를 수행하였다.

• 한국의사학회지
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• 제25권2호
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• pp.155-193
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• 2012

From the part "歷代醫學姓氏(Historic Doctors)" in "醫林撮要(Uirimchualyo)", the following has been noticed and concluded. 1. Because acupuncture was originated from stony needle, the word "石(sok)" contains the meaning of needle, and from this point on, words like 石(sok), 砭石(pyumsok), 箴石(Jamsok), 鑱石(Chamsok) had been derived. 2. The word 砭石(pyumsok) used in "Hwangjenaekyong(Yellow Emperor's Canon of Medicine or Hwangdineijing)" should be interpreted as acupuncture in a verb form, not a noun form. 3. 鑱石(Chamsok) or 鑱鍼(Chamchim) was used for surgical treatment for tumor, by cutting open tumors and pressing the pus out. Therefore, 砭石(pyumsok), 鑱石(Chamsok) are the same kind of needles, and 鑱鍼(Chamchim) is the tool improved from 鑱石(Chamsok) used in the Bronze Age. 4. Kwakpak put a note on 鑱石(Chamsok) in "山海經(Sanhaekyong)" that reads "it is defined as 砥鍼(Jichim) and treats tumor." This let us know the shape of 石(sok), 砭石(pyumsok), 鑱(Chamsok), 鑱鍼(Chamchim), and the stone that can be used as a surgical tool with slim & sharp shape is obsidian. 5. Because obsidian is only found around Mt. Baekdu and limited area in South Korea & Japan in Asia, it is closely related with the life & medical environment of the tribe "Mt. Baekdu". 6. The development of 鑱鍼(Chamchim) was influenced by surgical treatment used in early stage of civilization, and its origin is traced upto Gochosun dynasty. Korea's own traditional medical knowledge is derived from this surgical treatment skill. 7. Because the acupuncture is originated from Gochosun dynasty, 鍼(chim) was derived from 箴(Jam) of 箴石(Jamsok), 䥠(Chim) & 䥠(Chim) both were used for a time being, and finally settled into 鍼(Chim). 8. The word 針(Chim) showed up at Myung dynasty, and started to be used in Korea from early Chosun dynasty. 9. In the early Chosun dynasty, 鍼(Chim) was used for medical term, and 針(Chim) for non-medical term. In the mid Chosun dynasty, 針(Chim) was used as a term for tool, and 鍼(Chim) as a term for acupunctural medical treatment. 10. Under the order of King Sunjo, Dr. Yesoo Yang published "醫林撮要(Uirimchualyo)", added "醫林撮要續集(Sequel to Uirimchualyo)", and added "歷代醫學姓氏(Historic Doctors)" again which eventually made totally 13 books of "醫林撮要(Uirimchualyo)". In addition, many parts of "醫林撮要續集(Sequel to Uirimchualyo)" were quoted in "東醫寶鑑(Donguibogam)", and influenced much in publishing "Donguibogam". 11. In "歷代醫學姓氏(Historic Doctors)" of "醫林撮要(Uirimchualyo)", the same way in "Donguibogam", referred to 針(Chim) as a term for a needle, and 鍼(Chim) as a term for Acupuncture. 12. From the usage of 針(Chim) & 鍼(Chim), shown in "鄕藥集成方(Hyangyakjipsungbang)", "醫林撮要(Uirimchualyo)" and "東醫寶鑑(Donguibogam)", we can notice the spirit of doctors who tried to take over the legitimacy of Korean tradition, and their elaboration & historical view that expresses confidence on our own medical technology, through the wording 鍼(Chim).

• 한국육종학회지
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• 제42권3호
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• pp.280-283
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• 2010

1999년도에 분홍색의 대형 스탠다드 장미 'Silba87' 품종을 모본으로 화형이 우수하지만 흰가루병에 약한 적색 스탠다드 장미 'Bravo' 품종을 부본으로 인공교배하였다. 2000년에 파종을 실시하여 2080개체의 실생을 획득하여 이들을 대상으로 2001-2003년까지 3차에 거쳐 특성검정을 실시한 후 최종 특성검정 단계에서 기호도 조사를 실시한 결과 최종 선발 된 '원교 D1-37'을 2003년 농촌진흥청 농작물 직무육성 신품종 선정위원회를 거쳐 '노블레드'로 명명하여 국립종자원에 2004년 1월 26일 품종보호출원 하여(출원번호: 102004000035) 2005년 3월 16일 품종등록되었다(등록번호: 1149). '노블레드'의 화색은 적색으로 RHS 칼라챠트번호 46C이며 화형은 고심형의 화형이며 향기는 거의 없었다. 꽃잎수는 30.8개로서 '롯데로제'의 23.8개보다 많았으며 화폭은 14 cm로 '롯데로제'와 비슷했지만 화고가 6.0 cm로 높아 화형이 우수했다. 평방미터당 년간 절화수량은 125본이며 절화장은 71.9 cm 절화경경은 6.0 mm로 롯데로제보다 절화경경이 굵고 절화장은 약간 짧아 강건한 절화형태를 보인다.

• 치위생과학회지
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• 제22권1호
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• pp.57-66
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• 2022

Background: This study aimed to investigate the effect of selecting commercially available blending teas and applying them to bovine teeth on color change over time. Methods: After selecting healthy bovine teeth, using a cutting-disc, 105 specimens with a dimension of 5×5×3 mm were prepared, and 15 specimens were distributed to each group. Black tea was used as a positive control, water was used as a negative control, and blended tea of five types was used as an experimental group. First, pH and buffering capacity were measured with a pH meter, and tooth color was determined using a spectrophotometer before immersion in the blending tea solution and 1, 5, 7, 14, and 21 days after immersion. Thereafter, the shape change of the enamel surface was observed using a scanning electron microscope, and SPSS ver.26 was used to analyze the color change. Results: The average pH of the five blending teas in the experimental group was 3.78, and the pH of group 3 (strawberry rhubarb) was the lowest at 3.22. The pH levels of black tea and water were 5.19 and 7.30, respectively. The buffering capacity was the highest in group 3 at both pH levels of 5.5 and 7.0. The L^*a^*b^* color change according to immersion time was the largest in group 4 (rooibos yellow flower), and the amount of color change was large in black tea and group 4. As a result of observing the enamel surface of bovine teeth, changes in the surface shape were noted in all groups immersed in the experimental solution for 21 days, except for water. Conclusion: There was a significant difference between the experimental groups in terms of color change according to the immersion time, and color and enamel surface changes were observed in black tea and all experimental groups, except for water.