• The korean journal of orthodontics
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• v.33 no.2 s.97
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• pp.73-84
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• 2003

This study was performed to find out how much projection errors in the cephalometric measurements were made by vertical head rotation in taking posteroanterior cephalograms. 25 adults without any apparent facial asymmetry or severe sagittal skeletal discrepancy were selected and the posteroanterior cephalograms were taken with the head rotated $5^{\circ},\;10^{\circ}$ superior and inferior each to the reference $position(0^{\circ})$. The 7 height, 5 width and 6 angular measurements were taken at each 5 positions. Through the statistical analysis of all measurements taken at each rotated position, folowing results were obtained.1. The projection errors of height measurements were remarkably target than those of width or angular measure nents. f. Among the height measurements, the farther to the rotation axis the measurements were, the larger the projection errors were. 3. Among the width measurements, mandibular width and mandibular width of mandibular first molars showed significant differences between the values taken at each rotated position, while nasal width, maxillary width and intermolar width of maxillary first molars did not. 4. Among the angular measurements, the angle between horizontal reference line and the line that is connected to crista galli and antegonion or maxillare showed significant differences between the values taken at each rotated Position. The above results suggest that it is needed to the effort to keep constant head position for taking the useful posteroanterior cephalogra, because projection errors are caused by vertical head rotation.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.44 no.9
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• pp.54-62
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• 2007

In this paper, a novel wideband notched compact UWB antenna is designed to satisfy the licensed UWB frequency bandwidth($3.1{\sim}4.8$ GHz, $7.1{\sim}10.2$ GHz) by symmetrically arranging two adjacent sectorial loop antennas. The wideband($4.8{\sim}7.1$ GHz) notch can be obtained by inserting the inverted-L shaped slits on the patch. The designed UWB antenna has return loss lower than -10dB at 3.1 GHz and over, group delay value lower than 1 ns and the linear phase property. The optimized UWB antenna inserted the inverted-L shaped slits has return loss great than -10dB, 5 ns of group delay, nonlinear phase and decreased gain properties over the frequency band, 4.8 GHz to 7.1 GHz.

• Journal of the KSME
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• v.27 no.6
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• pp.504-514
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• 1987

복잡한 전자부품의 조립시에 필요한 열적 디자인에 관한 정보는 오래전부터 실험을 통하여 얻어지고 있다. 실험적 데이터를 이용하여 무차원 파라미터로 표시된 실험결과는 꼭 같지는 않지만 현상적으로는 비슷한 상황에 응용될 수 있다. 여기서는 학술문헌에 나타나 있는 자연대류에 관한 실험적인 상관관계식들과 프레임에 수직으로 꽂혀있는 균일가열 전자회로기판의 모델에서 얻어진 무차원 자료들을 비교하고자 한다. 대부분의 자료들은 수정채널 Rayleigh수(Ra")가 15~100범위에 속하며, 이러한 범위는 부품이 조밀하게 배치된 기관이 서로 좁은 채널을 이루고 있으며, 동시에 상당한 전력을 소비하고 있는 경우에 해당한다. Wirt와 Stutzman, Bar-Cohen과 Rohsenow의 일반상관관계식은 AT'||'&'||'T Bell 연구소에서 개발된 전자기기를 이용하여 수집한 실험데이터를 잘 표현하고 있으며 10 < Ra" <1,000범위에서 추천될 수 있다. 두개의 유사한 상관관계식과 비교할 때 상당히 좋은 예측을 보였으며 또한 Sparrow와 Gregg의 연구결과와도 잘 일치하므로 Ra" < 10인 경우에 Aung의 완전발달층류의 채널유동방식, Ra" > 1,000인 경우에는 Aung등의 단일 수직평판 근사식이 추천될 수 있다. Coyne의 알고리즘에 의한 계산치는 10

• The KIPS Transactions:PartC
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• v.14C no.6
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• pp.493-502
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• 2007

In this paper, we propose a handoff-aware DiffServ scheduler which intends to guarantee various QoS requirements of multimedia services for mobile nodes in TDD/CDMA based wireless networks. TDD is widely used duplexing mechanism in wireless communications. Unlike FDD, TDD allows a node to symmetrically communicate with a base station by using a single frequency band, resulting in high utilization of wireless resources. DiffServ is regarded as a relatively simple QoS support mechanism and thus it is easy to be extended. This is because DiffServ is not a per-flow based mechanisms and it does not require any signaling protocol. However, previously proposed DiffServ schedulers for wired networks can not be deployed directly into wireless networks since they do not consider properties of wireless networks. As a solution to the problem, DSS(DiffServ Supporting Scheduler) was proposed. DSS uses uplink channel, which is originally used for a node to require a base station to transmit packets, to support QoS efficiently. However, QoS does not consider handoff so that it can not support QoS for moving nodes from one cell to the other cell. Therefor. the proposed handoff support QoS mechanism is necessary for TCC/CDMA networks. The proposed scheme allows a mobile node to achieve seamless service without QoS degradation even for the handoff duration.

• Tuberculosis and Respiratory Diseases
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• v.47 no.1
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• pp.97-102
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• 1999

Multiple symmetric lipomatosis(Madelung's disease) seems to represent a relatively common disease in Europe but has not been described in the Korean literature. It is characterized by highly typical symmetric deposits of subcutaneous fat on the neck, arms, and upper part of the trunk. The localized increase of adipose tissue is hyperplastic in nature and probably results from a local defect in adrenergic stimulated lipolysis. Multiple symmetric lipomatosis is frequently, but inconstantly, associated with alcoholism, liver disease, glucose intolerance, and hyperuricemia, but their etiologic role remains to be established. Clinical importance is the apparent high incidence of malignant tumors of the upper airways requiring through ear, nose, and throat and internal examination of all patients. Another importance is possibility of airway obstruction due to mass effect. Dietary treatment and weight loss are of limited value. Surgical treatment gives only temporary relief and should be restricted to patients with functional impairment. We report a case of a 63-year-old man with multiple symetric lipomatosis and alcoholism.

• The Korean Journal of Zoology
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• v.31 no.4
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• pp.334-343
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• 1988

Five types of synaPses were differentiated in the antennal lobe or Pieris rapoe. aev are in general axo-dendritic synapses and have symmetrical contacts. The type I synapses contain the uniformly round vesicles of medium size, and consist of the 11% of all synapses in the antennal lobe. The type synapses are filled with the small flat and densely arranged (19%). The type III synapses possess medium-sized round vesicles and dense core ones(24%). The type IV synapses are characterized by such three kinds of vesicles as small round, small flat and dense core vesicles(33%). The type V synapses exhibit the presence of medium-sized round, large round and dense core vesicles(13%). The removal of the left antenna on its proximal portion caused the type IV boutons of the above ave types in ipsilateral antennal lobe to turn into dark or semidark degenerative changes. Therefore, it was concluded that many of the antennal receptor cells projected into the brain terminate in the antennal lobe to form type IV synapses together with the dendrites. 배추회나비 뇌의 촉각엽에 있는 신경세포들은 5가지의 신경연접을 형성하는 것으로 관찰되었다. 이 신경연접들은 모두 축색과 수상돌기간의 연접으로 대칭연접이었다. 제1형 신경연접은 축색종말내에 중등도크기의 단형 연접소포를 가지고 있었고, 촉각엽에 있는 5가지의 신경연접중 11%의 출현빈도수로 관찰되었다. 제2형 신경연접의 축색종말에는 장형과 도형의 2가지 연접소포가 포함되어 있었는데, 모두 소형이었으며 이같은 연접소포들이 축색 종말내에서 조밀하게 관찰되었다. 제2형 신경연접의 출현 빈도수는 19%이었다. 제3형 신경연접은 축색 종말내에 중등도크기의 도형 연접소포와 DENSE CORE VESICLE을 포함하고 있었고 그 출현빈도수는 24%이었다. 제4형 신경연접은 축색총말내에 소형의 도형, 소형의 장형 연접소포 및 DENSE CORE VESICLE의 3가지 연접소포를 가지고 있었고 출현빈도수는 촉각엽에서 가장 큰 33%이었다. 제5형 신경연접은 축색종말내에 중등도크기의 원형, 대형의 원형연접소포 및 DENSE CORE VESICLE을 포함하였고 13%의 출현빈도수로 관찰되었다. 배추횐나비의 촉각에 있는 지각신경세포가 뇌의 촉각엽으로 뻗어 들어가 위의 5가지 신경연접중 어느 형을 형성하는지를 관찰하기 위하여 좌측 촉각의 기부를 제거하여 지각신경세포를 절단하였는데 그 결과, 좌측 촉각엽에서 제4형의 신경연접이 퇴행성 변화를 나타내었다. 그러므로 촉각의 지각신경세포는 뇌의 같은 족 촉각엽에 뻗어와 제4형 신경연접을 형성한다고 결론되었다.

• Journal of the Korean earth science society
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• v.28 no.7
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• pp.936-946
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• 2007

Analytical geopotential field in balance with the sectoral mode (the first symmetric mode with respect to the equator) of the Rossby-Haurwitz wave on the inclined rotation axis was derived in presence of superrotation background flow. The balanced field was obtained by inverting the divergence equation with the time derivative being zero. The inversion consists of two steps, i.e., the evaluation of nonlinear forcing terms and the finding of analytical solutions based on the Poisson's equation. In the second step, the forcing terms in the from of Legendre function were readily inverted due to the fact that Legendre function is the eigenfunction of the spherical Laplacian operator, while other terms were solved either by introducing a trial function or by integrating the Legendre equation. The balanced field was found to be expressed with six zonal wavenumber components, and shown to be of asymmetric structure about the equator. In association with asymmetricity, the advantageous point of the balanced field as a validation method for the numerical model was addressed. In special cases where the strength of the background flow is a half of or exactly the same as the rotation rate of the Earth it was revealed that one of the zonal wavenumber components vanishes. The analytical balanced field was compared with the geopotential field which was obtained using a spherical harmonics spectral model. It was found that the normalized difference lied in the order of machine rounding, indicating the reliability of the analytical results. The stability of the sectoral mode of Rossby-Haurwitz wave and the associated balanced field was discussed, comparing with the flrst antisymmetric mode.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.213-219
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• 2003

본 연구에서는 새로운 개념의 건조방법을 연구하여 곡물건조의 변화를 도모하고자 원적외선ㆍ열풍 복합열을 이용한 곡물건조기를 개발하게 되었다. 그 결과를 요약하면 다음과 같다. 가. 방사체길이가 1,680mm일 때 보다 1,470mm일 때가 방사체 표면온도가 높게 나타났고, 안정적인 것으로 나타났다. 열풍온도를 5$0^{\circ}C$로 설정했을 때 방사체의 표면온도분포는 280-29$0^{\circ}C$을 유지하였고, 6$0^{\circ}C$일 때는 30$0^{\circ}C$ 부근에서 유지되는 것을 확인할 수 있었다. 두 조건 모두에서 온도편차는 크게 나타나지 않았으므로 균일 건조가 이루어지는 것을 의미하며, 곡물의 품질저하에 영향을 미치지 않는 것으로 판단된다. 나. 열풍온도 5$0^{\circ}C$, 조사거리 125mm, 방사체 길이 1,470mm에서 방사체 길이방향으로 위치에 따라서 온도편차를 측정했을 때 버너를 기점으로 해서 근거리에서부터 원거리까지 균등 분할하여 5점의 온도를 측정하여 그 변화곡선을 분석한 결과 위치 3에서 온도가 높았고, 계속해서 위치 4, 5, 2, 1순으로 나타났다. 버너의 근거리에서보다 원거리에서 온도가 높게 나타난 것은 원적외선방사체를 통과하는 열풍이 빠져나가도록 되어있는 열풍유동관이 버너 원거리에 위치하고 있어 버너에 불꽃이 점화되면서 열풍이 방사체 끝쪽으로 유동되기 때문이다. 다. 건조실 수직면 길이방향의 온도는 열풍공기가 열풍실에서 유입되는 하단부이 온도가 높게 나타났고, 버너쪽과 송풍기쪽의 온도차는 나타나지 않아 온도분포의 좌우 대칭이 잘 되어 균일 건조가 되는 것으로 판단된다 이러한 현상은 건조실의 수평면에 대해서도 같은 현상이 나타났다. 라. 바닥면에서 상부로 올라갈수록 낮은 온도분포를 나타내고 있는 것은 상부에는 외부공기가 유입되면서 온도가 떨어지는 반면 하부에는 외부공기 유입이 적기 때문으로 사료된다. 또한 열풍실의 길이방향 위치별 온도 분포에서도 같은 현상으로 나타났고, 버너쪽과 송풍기쪽의 온도편차는 나타나지 않아 균일 건조를 기대할 수 있다. 마. 열풍온도를 45$^{\circ}C$로 설정하고 조사거리와 방사체 길이를 각각 119, 1,470mm로 하여 벼의 건조성능시험을 열풍건조기(대비구)와 비교시험 결과 시험구에서 건감률, 건조소요에너지가 각각 0.58%(w.b.), 470kcal/kg - water로 대비구보다 각각 건감율은 23% 높았고, 건조소요에너지는 2%의 절감되었다. 바. 건조기에서 발생되는 소음은 버너쪽 근처에서는 대비구 94.12㏈의 87%에 불과하였으나, 거리가 멀어질수록 차이는 크지 않았다. 이것은 버너에서 멀어질수록 외부적인 요인이 소음에 영향을 미쳤기 때문인 것으로 생각된다. 사. 시작기와 대비구간의 경제성에서 시작기의 구입가격이 20% 비싸기 때문에 시간당 고정비가 높았으나, 건조성능이 우수하여 건조비용이 69,350원/톤으로 대비구보다 14% 절감되는 것으로 나타났다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.2
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• pp.94-102
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• 2020

This study conducted a meta-analysis of the effects of self-management intervention for reducing the depression and anxiety of osteoarthritis patients. The research sources were PubMed, EMBASE, CINAHL, Ovid-MEDLINE and Korean databases from the Korean and foreign literature published until September 30, 2019. The R version 3.5.1 program was used to identify the effectiveness of self-management intervention. As a result, 11 studies from a total of 1,877 articles in the relevant literature were analyzed, and the total number of participants was 2,751. The results showed that the overall effect size for reducing depression and anxiety was -0.44 (95% CI: -0.66, -0.22) in osteoarthritis patients (p <.001). On the sub-analysis, depression was -0.37 (95% CI: -0.66, -0.08), and anxiety was -0.56 (95% CI: -0.92, -0.20). To explain the heterogeneity, the meta-ANOVA was the setting, duration, and provider of intervention. Analysis of the publication bias was performed by a Funnel plot, which was visually relatively symmetrical and was not asymmetric according to Egger's Regression test (bias=0.19, p=.928). The results of this study established clinical evidence by identifying the effects of self-management intervention for reducing the depression and anxiety of osteoarthritis patients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.608-616
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• 2018

If a general nonlinear system is linearized by the successive multiplication of the 1st and 2nd order systems, then there are four types of poles in this linearized system: the pole of the 1st order system and the equal poles, two distinct real poles, and complex conjugate pair of poles of the 2nd order system. Linear Quadratic (LQ) control is a method of designing a control law that minimizes the quadratic performance index. It has the advantage of ensuring the stability of the system and the pole placement of the root of the system by weighted matrix adjustment. LQ control by the weighted matrix can move the position of the pole of the system arbitrarily, but it is difficult to set the weighting matrix by the trial and error method. This problem can be solved using the characteristic equations of the Hamiltonian system, and if the control weighting matrix is a symmetric matrix of constants, it is possible to move several poles of the system to the desired closed loop poles by applying the control law repeatedly. The paper presents a method of calculating the state weighting matrix and the control law for moving the equal poles with Jordan blocks to two real poles using the characteristic equation of the Hamiltonian system. We express this characteristic equation with a state weighting matrix by means of a trigonometric function, and we derive the relation function (${\rho},\;{\theta}$) between the equal poles and the state weighting matrix under the condition that the two real poles are the roots of the characteristic equation. Then, we obtain the moving-range of the two real poles under the condition that the state weighting matrix becomes a positive semi-finite matrix. We calculate the state weighting matrix and the control law by substituting the two real roots selected in the moving-range into the relational function. As an example, we apply the proposed method to a simple example 3rd order system.