• 한국통신학회논문지
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• 제21권10호
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• pp.2710-2723
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• 1996

2-dimensional scattering problem of electromagnetic waves by a periodic strip grating on a grounded dielectric slab in case of oblique incidence and arbitrary polarization is analyed by the vector Floquet modal expansion method. Solution convergence versus number of Chebyshev polynomial terms representing the unknown strip current density and number of space harmonics is examined, and some numerical results such as variation of power of significant space harmonics(scattered mode) are compared with those obtained by previous method. In particaluar, the relationship between Bragg blazing phonmena and characteristics mode(current) on the srip is discussed in detail.

• 한방비만학회지
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• 제6권2호
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• pp.29-41
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• 2006

Subclinical hypothyroidism is defined as a normal serum free thyroxine level combined with an elevated thyroid stimulating hormone level. The causes of subclinical hypothyroidism are the same as those of overt hypothyroidism. There is good evidence that subclinical hypothyroidism is associated with progression to overt disease. The management of subclinical hypothyroidism is remains controversial. Patients with a serum thyroid stimulating hormone level greater than 10 mU/L have a higher incidence of elevated serum low-density lipoprotein cholesterol concentrations; however, evidence is lacking for other associations. There is insufficient evidence that hormone treatment of subclinical hypothyroidism is beneficial. The use of thyroid stimulating hormone level lone as a diagnostic and assessment tool for hypothyroidism is inadequate because this test cannot identify numerous conditions this sentence is unclear in its meaning. Using an expanded list of clinical signs and symptoms associated with dysfunction of the Hypothalamus-Pituitary-Thyroid axis, it is possible to hypothesize that subclinical hypothyroidism may be more common in a population of patients with early signs of age-related diseases than most practitioners realize. To improve thyroid function in subclinical hypothyroidism patients, practitioners should become familiar with foods and nutrients that can hinder or support thyroid function.

• Imaging Science in Dentistry
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• 제49권3호
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• pp.235-240
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• 2019

Osteosarcoma is the most common primary bone tumor after plasma cell neoplasms. Osteosarcoma has diverse histological features and is characterized by the presence of malignant spindle cells and pluripotent neoplastic mesenchymal cells that produce immature bone, cartilage, and fibrous tissue. Osteosarcoma most frequently develops in the extremities of long bones, but can occur in the jaw in rare cases. The clinical and biological behavior of osteosarcoma of the jaw slightly differs from that of long-bone osteosarcoma. The incidence of jaw osteosarcoma is greater in the third to fourth decades of life, whereas long-bone osteosarcoma mostly occurs in the second decade of life. Osteosarcoma of the jaw has a lower tendency to metastasize and a better prognosis than long-bone osteosarcoma. Radiographically, osteosarcoma can present as a poorly-defined lytic, sclerotic, or mixed-density lesion with periosteal bone reaction response. Multi-detector computed tomography is useful for identifying the extent of bone destruction, as well as soft tissue involvement of the lesion. The current case report presents a fibroblastic osteosarcoma involving the left hemimandible with very unusual radiographic features.

• Corrosion Science and Technology
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• 제17권6호
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• pp.292-300
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• 2018

The modeling of 3D finite elements based on CAD data has been used to detect sites of corrosion defects in buried pipes. The results generated sophisticated profiles of electrolytic potential and vectors of current distributions on the earth surface. To identify the location of defects in buried pipes, the current distribution on the earth surface was projected to a plane of incidence that was identical to the pipe locations. The locations of minimum electrolytic potential value were found. The results show adequate match between the locations of real and expected defects based on modeling. In addition, the defect size can be calculated by integrating the current density curve. The results show that the defect sizes were $0.74m^2$ and $0.69m^2$, respectively. This technology may represent a breakthrough in the detection of indirect damage in various cases involving multiple defects in size and shape, complex/cross pipe systems, multiple anodes and stray current.

• 대한두경부종양학회지
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• 제37권2호
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• pp.87-90
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• 2021

Solitary fibrous tumor (SFT) is rare mesenchymal tumor usually arising from pleura. SFT can be found at all anatomic site in our body but incidence of SFT is much lower in head and neck region especially at lower neck area. We found a case of SFT that presented as a lower neck mass in a 41-year old woman. Ultrasonography showed a 3×1cm sized hypoechoic mass in the intermuscular fat plane of left lower neck, and computed tomography showed a well circumscribed, low-density mass with contrast enhancement. Fine needle aspiration showed no malignant cells with abundant red blood cells, but it was not possible to completely rule out malignant tumors or nodules clinically. Surgery was performed to make a definitive diagnosis and histopathology showed tightly packed, round to fusiform cells with staghorn shaped vessels at microscopic examination. The tumor cell were positive for CD34 but negative for CD31 and S-100 protein.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3121-3125
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• 2023

Neutron conversion detectors that use ¹⁰B-enriched boron carbide are feasible alternatives to ³He-based detectors. We prepared boron carbide films at micron-scale thickness using direct-current magnetron sputtering. The structural characteristics of natural B₄C films, including density, roughness, crystallization, and purity, were analyzed using grazing incidence X-ray reflectivity, X-ray diffraction, X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectrometry, and scanning electron microscopy. A beam profile test was conducted to verify the practicality of the ¹⁰B-enriched B₄C neutron conversion layer. A clear profile indicated the high quality of the neutron conversion of the boron carbide layer.

• 농약과학회지
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• 제17권4호
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• pp.379-387
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• 2013

지자체에서 배양하여 보급되고 있는 농업미생물 활용을 증진할 목적으로 18개 농업기술센터에서 51종의 미생물을 수집하여 작물생장촉진 및 식물병 방제와 관련한 기능성인 항균활성, 인산가용화, IAA 및 siderophore 생성능력, 질소고정능력, 가수분해활성을 비교 조사하여 최종적으로 항균활성이 우수하고 다양한 농업적 기능을 보이는 Panenibacillus polymyxa CW균주를 선발하였다. P. polymyxa CW균주는 벼 도열병균, 고추 탄저병균, 채소류 시들음병균, Phomopsis sp., 양파 검은곰팡이병균, 잘록병균(Rhizoctonia solani) 및 고추 역병균에 대하여 높은 항균활성을 보였다. 시험 병원균 중 잘록병균을 제외한 모든 병원균에 대하여 P. polymyxa CW균주는 농과원에서 보유하고 있는 P. polymyxa AC-1보다 높은 항균활성을 보였다. P. polymyxa CW균주는 항균활성 외에도 siderophore 생성, IAA 생성 및 질소고정 능력이 우수한 것으로 나타났다. P. polymyxa CW균주의 siderophore 생성능력은 P. polymyxa AC-1과 비슷하였으나 IAA 생성이나 질소고정능력은 P. polymyxa AC-1보다 우수하였다. 그러나 가수분해능력에 있어서는 P. polymyxa CW균주와 P. polymyxa AC-1균주 모두 활성을 보이지 않았다. 고추 흰가루병을 대상으로 P. polymyxa CW균주를 농도별로 처리하고($10^8$, $10^7$. $10^6$ cfu/ml) 처리 후 10일에 병 억제효과를 조사하였을 때, 가장 높은 농도처리에서 병 발생을 68.3%까지 억제하였다. P. polymyxa CW균주의 처리농도가 감소됨에 따라 병 방제효과도 비례해서 감소되었다. 또한 토마토 흰가루병에 대하여 P. polymyxa CW균주 배양액을 $10^6$, $10^7$, $10^8$ 농도로 희석하여 처리하고 7일 후에 병 발생정도를 조사한 결과, 무처리의 병반면적율이 56.3%인데 비하여 0.03, 19.5, 45.7%로 병 발생을 현저히 억제하는 것으로 나타났다. 고추 흰가루병의 경우처럼 토마토 흰가루병에 대한 P. polymyxa CW균주의 방제효과도 처리농도에 비례하는 것으로 나타났다. P. polymyxa CW균주는 고추 및 토마토 흰가루병에 대하여 높은 방제효과를 보였으며, 방제효과가 밀도에 좌우되는 것으로 나타나 시험한 두가지 흰가루병 방제에 대한 작용기작은 항생작용으로 추측되며 효과적인 병 방제를 위해서는 $10^8$ cfu/ml 이상 농도로 처리해야 할 것으로 생각되었다. 이상의 결과를 근거로 P. polymyxa CW균주는 고추 및 토마토 흰가루병 방제를 위한 유망한 방제제로 사용될 수 있을 것으로 사료된다.

• 한국토양비료학회지
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• 제33권1호
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• pp.24-31
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• 2000

도라지 재배지 32개 농가의 토양 물리적 성질을 조사하고 근경부패병 발병 및 수량에 미치는 영향을 조사한 결과는 다음과 같다. 발병율과 유효토심은 Y = -0.747X + 88.19($R^2=0.394^{***}$), 토양경도는 Y = 4.36X + 8.93($R^2=0.201^*$), 용적밀도는 Y = 104.7X - 80.99($R^2=0.295^{**}$), 점토함량과는 Y = 1.24X + 14.14($R^2=0.196^*$), 토양공극과 Y= -3.l1X + 215.9($R^2=0.220^*$), 미사함량과는 Y = -0.75X + 67.85($R^2=0.178^*$)의 상관을 나타냈다. 수량은 토심과 Y = 0.263X + 0.971($R^2=0.105^*$), 경도는 Y = -1.712X + 30.60($R^2=0.109^*$), 자갈함량은 Y= -0.9172X + 45.74($R^2=0.113^*$), 점토함량은 Y = -0.688X+32.74($R^2=0.158^*$), 공극률은 Y = 1.974X -93.19($R^2=0.231^*$), 미사함량 Y = 53.05X - 108.65($R^2=0.232^{**}$)의 상관이 있었다. 위의 결과 다년생 도라지 재배적지는 유효토심 1m 이상, 토양경도는 $5kg\;cm^{-2}$ 이하, 용적밀도는 $1.0Mg\;m^{-3}$ 정도, 공극율은 58~63%, 수분함량은 13~17%, 점토함량은 5~10%, 미사함량은 38~64%가 좋은 것으로 나타났으며 토성은 미사질양토가 가장 좋은 것으로 분석되었다.

• 대한정형외과학회지
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• 제56권4호
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• pp.334-340
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• 2021

목적: 족관절 골절과 골다공증의 상관관계를 알아보기 위하여 족관절 골절 환자의 요추체와 대퇴골의 골밀도 값을 분석하였다. 대상 및 방법: 2002년 4월부터 2014년 7월까지 족관절 골절로 진단받고, 수상 후 1년 이내 골밀도 검사를 시행했던 100명의 환자를 분석하였다. 수상 당시 연령에 따라 50세 미만, 50세 이상 70세 미만, 70세 이상의 세 군으로 나누었고, 골절의 유형은 단과골절, 양과골절, 삼과골절로 분류하였다. 골밀도는 요추체(요추 1-4번 평균치), 대퇴골 경부, 대퇴골 전자부, 대퇴골 전체의 T점수, Z점수 및 골밀도 절대값(g/cm²)을 분석하였다. 결과: 족관절 골절 환자는 여자의 수가 남자보다 3.2배 많았다. 연령별 군에 따른 골다공증의 유병률은 50세 미만 군에서 0%, 50-69세 군에서 24.2%, 70세 이상 군에서 15%였고, 이중 50-69세 군에서 삼과골절 환자의 30%가 골다공증으로 나타났다. 전체 환자 군에서 연령이 낮을수록 단과 골절의 빈도가 높게 나타났다. 골밀도 값과 골절 유형과의 관계는 요추체의 T점수와 골밀도 절대값(g/cm²) 및 대퇴골 경부의 Z점수가 낮을수록 삼과 골절의 빈도가 증가하였으나, 이외의 다른 지표는 골절의 유형과 통계적으로 뚜렷한 상관관계를 보이지 않았다. 결론: 100명의 족관절 골절 환자를 분석한 결과, 여자의 수가 남자보다 많았으며 골다공증의 정도가 심하지 않을수록 삼과골절보다는 단과골절의 발생 빈도가 높은 경향을 보였지만, 족관절 골절과 대퇴골 및 요추의 골밀도 값과의 상관관계는 통계적으로 의미있게 나타나지 않았다.

• 한국임상수의학회지
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• 제23권3호
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• pp.291-299
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• 2006

During long bone lengthening, there are many disadvantages including axial deviation, malalignment and re-fracture which are commonly encountered inspite of its proven abilities. To study the effects of intramedullary K-wire application on the lengthening of long bone, ten skeletally mature mongrel dogs were separated into two groups(Group I, II). Right femurs of group I(5 dogs) were fixed with only monolateral external fixator after subperiosteal osteotomy. Right femurs of group II(5 dogs) were fixed with mono lateral external fixator and intramedullary K-wire after subperiosteal osteotomy. Lengthening was started at 7 days after the surgery with the rate of 0.5 mm per day for 5 weeks and the dogs were sacrificed after 15 weeks postoperatively to examine histologic differences and evaluate bone mineral density. Radiographic examination at an interval of two weeks was done to evaluate the type of callus formed and to analyze complications including instability of external skeletal fixation and axial deviation. Bone mineral density at the lengthened area and contralateral nonlengthened area were measured using quantitative computerized tomography. Histological examination of regenerated bone was performed using Masson's trichrome stain method. The radiographs demonstrated poor callus formation, higher incidence of axial deviation and screw loosening in the group I compared to the group II. The bone mineral density at the lengthened area in the group II was higher than that of the group I(P<0.05). Histological examination showed that the new bone trabeculae in the group II were greater than that of the group I. In conclusion, the combination of monolateral external fixator and intramedullary K-wire can prevent pin loosening, axial deviation and reduce healing period in dogs.