• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.2A
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• pp.99-108
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• 2002

In this paper, we discuss the effect of imperfect knowledge of the transmission channel on the M-QAM SER performance of space-time block codes. Because the channel knowledge is used for decoding of space-time block codes, the imperfect channel knowledge can degrade the performance of space-time block codes. In this paper, the channel mismatch error is modeled as errors in the estimation of the channel due to noise and errors due to the variation of the channel. We derive the analytic expression for the symbol error rate (SER) as a function of the average signal to interference ratio (SIR) per channel including the terms of channel mismatch errors. Simulation results show that the acceptable levels of channel estimation error is 10$\^$-3/ and that of channel variation is f$\_$d/T$\_$B/=0.001 at SNR=20dB in space-time block codes.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.6
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• pp.1-8
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• 2019

To resolve the conservative requirements for clear headed-bar spacing in KBC 2016 and ACI 318-08, two 2/3-scale exterior beam-column connections were tested under cyclic seismic loading. The seismic tests primarily explored the effect on their seismic performance of using (a) small clear spacings and (b) multiple layers of headed reinforcements in the beam. Also, the previous test data were thoroughly analyzed. It was concluded that the clear bar spacing of 2d_b or the use of two bar layers might be permitted for headed reinforcements embedded in exterior beam-column connections.

• ETRI Journal
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• v.36 no.5
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• pp.761-771
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• 2014

Long-Term Evolution employs a hard handover procedure. To reduce the interruption of data flow, downlink data is forwarded from the serving eNodeB (eNB) to the target eNB during handover. In cellular networks, unbalanced loads may lead to congestion in both the radio network and the backhaul network, resulting in bad end-to-end performance as well as causing unfairness among the users sharing the bottleneck link. This work focuses on congestion in the transport network. Handovers toward less loaded cells can help redistribute the load of the bottleneck link; such a mechanism is known as load balancing. The results show that the introduction of such a handover mechanism into the simulation environment positively influences the system performance. This is because terminals spend more time in the cell; hence, a better reception is offered. The utilization of load balancing can be used to further improve the performance of cellular systems that are experiencing congestion on a bottleneck link due to an uneven load.

• Clinical and Experimental Pediatrics
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• v.57 no.2
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• pp.91-95
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• 2014

Griscelli syndrome type 2 (GS2) is a rare autosomal recessive disease caused by mutations in the RAB27A gene. It is characterized by cutaneous hypopigmentation, immunodeficiency, and hemophagocytic lymphohistiocytosis. We describe 2 brothers who had GS2 with clinically diverse manifestations. The elder brother presented with a purely neurological picture, whereas the younger one presented with fever, pancytopenia, hepatosplenomegaly, and erythema nodosum. Considering that cutaneous hypopigmentation was a common feature between the brothers, genetic analysis for Griscelli syndrome was performed. As the elder sibling had died, mutation analysis was only performed on the younger sibling, which revealed a novel homozygous mutation in the RAB27A gene on chromosome 15 showing a single-base substitution (c.136T>A p.F46I). Both parents were heterozygous for the same mutation. This confirmed the diagnosis of GS2 in the accelerated phase in both siblings. The atypical features of GS2 in these cases are a novel mutation, isolated neurological involvement in one sibling, association with erythema nodosum, and 2 distinct clinical presentations in siblings with the same genetic mutation.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.6B
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• pp.559-568
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• 2002

In this paper, we studied on combining the control of transmission fates and power for the real system where a finite set of transmission rates are used. In [1], the combined control of transmission rates and power was first researched, and suggested the Selective Power Control (SPC) algorithm. However, it can't guarantee the minimum rate to each user and results in frequent changes of rate due to oscillation of the SIR (Signal to Interference Ratio) values. As a main purpose of this paper, we derive a formulation model and propose a distributed iteration algorithm to solve these problems. To evaluate the performance of the proposed algorithm, we carried out numerical analysis and computational experiments. The results indicate that the proposed algorithm achieves better throughput than conventional one by keeping the low average transmission power.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.112-121
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• 2008

Nowaday the supply chain competitiveness is emphasized more and more than a company's own competitiveness. One of the most important processes in import and export is a publication over the Bill of Loading. In the publication of those bills S/R(shipping request) and check B/L for reviewing are circulated among consignors, forwarders, shipping companies and airlines by fax and e-mail. Or there should be expensive a One to One system, like an EDI. Each party has to re-input S/R data to their own systems and check it several times. The S/R data are converted digital to analog type and analog to digital repeatedly to check in the process. As the process goes by there can be not only input data errors but also waste of time and cost. ECR(electronic character recognition) is a technology can solve the Problem. Considering the data structure of documents in many systems used ECR samples SIR data from documents written in the digital type. But it is not enough with it only. To make N to N composition in reality more efficient we make a documents hub on the web reengineering the existing process to One to One relation. The ECR documents hub system has given us beneficial effects over a year throughout a field test.

• Journal of Chest Surgery
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• v.54 no.6
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• pp.439-448
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• 2021

Remodeling is a commonly encountered term in the field of cardiothoracic surgery that is often used to describe various pathophysiological changes in the dimension, structure, and function of various cardiac chambers, including the aorta. Stanford type A or DeBakey type 1 aortic dissection (TAAD) is a perplexing pathologic condition that can present surgical teams with the need to navigate a maze of complex decision-making. Ascending or hemi-arch replacement leaves behind a significant amount of distal diseased aortic tissue, which might have a persistent false lumen or primary or secondary intimal tears (or communications between lumina), which can lead to dilatation of the aortic arch. Unfavorable aortic remodeling is a major cause of distal aortic deterioration after the index surgery. Cardiac surgeons are aware of post-surgical cardiac chamber remodeling, but the concept of distal aortic remodeling is still idealized. The contemporary literature from established aortic centers supports aggressive management of the residual aortic pathology during the index surgery, and with continuing technical advancements, endovascular stenting options are readily available for patients with TAAD or for complicated type B aortic dissection cases. This review discusses the pathophysiology and treatment options for favorable distal aortic remodeling, as well as its impact on mid- to long-term outcomes following TAAD repair.

• The Korean Journal of Nuclear Medicine
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• v.13 no.1_2
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• pp.37-43
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• 1979

This is an analysis of 39 patients studied at the Yonsei Medical Center from January, 1976 to March 1979. Of these35 patient were suspected of having hypothalamic insufficiency and subjected to the L-Dopa stimulation test to observe growth hormone sceretory function while four acromegaly patient received the glucose loading test and L-Dopa stimulation test. The results are as follows: 1. The basal level of GH in the various disease was as follows: a. The basal level was lower than the control level but was not statistically significant b. In diabetes the mean value tended to be higher than the control level but was not significant statistically c. In all four acromegaly patients the GH level was significantly higher than the control level 2. Of 13 patients with diabetes, nine had diabetic retinopathy, and of those nine, sir showed increased L-Dopa response. However, of the four non retinopathic DM patients, only one showed increased response to L-Dopa. 3. Two patients out of ten with Sheehan's syndrome responded to L-Dopa stimulation. 4. One Patient of eight with pituitary chromophobe adenoma responded to L-Dopa stimulation. 5. Four acromegaly patients revealed 3 acidophilic adenoma and one chromophobe adenoma histologically. Of patients receiving the L-Dopa stimulation test. Two showed a paradoxical response. Two patients who received the glucose loading test showed supressed response. 6. Of two craniopharyngioma patients, one showed increased GH response after L-Dopa stimulation. Increased response of GH after L-Dopa stimulation was seen in one of two craniopharyngioma patients and also in one of two patients with

• Journal of Preventive Medicine and Public Health
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• v.26 no.1 s.41
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• pp.65-73
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• 1993

This study was carried out to evaluate the relationship between the biological lead exposure indices and air lead concentrations measured by personal air samplers. The 72 occupationally lead exposed workers were observed and the bioiogical lead Exposure indices chosen for this study were blood lead(PbB), urine lead(PbU), zinc protoporphyrin in whole blood(ZPP), $\delta$-aminolevulinic acid in urine(ALAU), $\delta$-aminolevulinic acid dehydratase activity (ALAD), coproporphyrin in urine(CPU) and hemoglobin(Hb). The workers were divided into four groups by air lead concentrations: Group I; under $0.05mg/m^3$, Group II; $0.05-0.10mg/m^3$, Group III; $0.10-0.15mg/m^3$ and Group IV; and over $0.15mg/m^3$. For evaluation the relationship between the biological lead exposure indices and air lead concentrations was used as correlation coefficients. The results obtained were as follows: 1. In Group I, II, III and IV, the mean value of PbB were $25.45{\pm}1.84{\mu}g/dl,\;27.87{\pm}3.53{\mu}g/dl,\;31.21{\pm}1.76{\mu}g/dl\;and\;47.02{\pm}13.96{\mu}g/dl$. Between Group IV and other groups showed statistically significant difference(p<0.05). 2. There was an increasing tendency of PbB, PbU, ALAU and ZPP according to the increase the mean air lead concentration, while ALAD has decreasing tendency. CPU and Hb did not show any constant tendency. 3. Correlation coefficients between PbB, PbU, ZPP, ALAU, ALAD, CPU, Hb and air lead concentration were 0.95, 0.83, 0.89, 0.72, -0.83, 0.51 and -0.45 respectively, and regression coefficient between PbB(Y) and PbA(X) was Y=126.8746X+16.9996(p<0.01).

• Korean Journal of Heritage: History & Science
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• v.38
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• pp.5-42
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• 2005

Based on a field investigation of intangible cultural asset # 2, author Sir Shin Seok-bong of Daejeon Metropolitan Cityinvestigated the music of Antaek-gut, which is the base and core of Anjoon-gut, and found the following musical features: A Jang-gu(drum) and Kkoaengkwari(gong) were used to recitethe Sutra(kyungmoon) of Anjoon-gut. The Jang-gu, located on the right side, played an accompaniment role with regular beats when the Sutra was recited. The Kkoaengkwari, located on the left side, played the role of covering the caesura of the Sutra passages, so it is played with various rhythmic variations in accordance with Kojang(鼓杖). This is one way of playing Korean national classical music that has temporary caesuras, depending on the rector's bre! ath or the contents of a Sutra during the Sutra chanting, with the Jang-gu covering the pause with its variation. In other words, when being played in concert, the instruments that play the main melody are at rest while another instrument takes its turn to play the main melody as a form of prolonged sound. The rhythmic cycles of the sutras of Antaek-gut recited with this instrumental accompaniment consist of five types; a) Woemarch-jangdan (a single beat) of 4 meter by 3 bit, b) Dumarch-jangdan (two beats) of 8 meter by 3 bit, c) Saemarch-jangdan (three beats) of 4 meter by 3 bit with a fast tempo, d) Mak-gojang, uniform beats with a standardized rhythm, and e) incomplete beats deviated from the regular beats. Sir Shin Seok-bong chanted Chang (唱), a traditional native song which he called 'Cheong (淸)' with a cycle of 'Dumarch-jangdan' throughout the places of Antaek-gut. Only 'Toesonggyung' a chant for the gate that was the last location of the Antaek, was chanted with a cycle of 'Woemarch-jan! gdan'. In addition, 'Saemarch-jangdan' and 'Mak-gojang' that had comparatively faster tempos than the former two jangdans, were played without a chant when a female shaman was dancing and catching her spirit-invoking wand. The 'Saemarch-jangdan', particularly, was played while dancing began at a relatively slow tempo, then proceeded at a violent tempo and then back again to the slow tempo. This shows one of the representative tempos of our music with a slow-fast-slow tempo. The organizational tones were 'mi-la-do'-re'', and its key tones of 'mi-la-do'' were performed with perfect fourth and minor third, which was the same as those of Menari-tori. However, it did not show a typical Sigimse, an ornamental tone, of Menari-tory, whose first tone, 'mi', is vibrated and its Sigimse is gliding down from the tone 're' to 'do'. That is because the regional tone-tori of Chungcheong-do have a relatively weaker musical expression than that of Gyeongsang-do. In addition, the rhythmic types in accordance with the words of a song for the Antaek-gut music had a comparatively faster tempo than the other sutras. Also, it was only with 'Toesonggyeong' that the tone 'la' continuously appeared throughout the melody and showed 'a syllabic rhythm', while other places consisted of either a 'syncopation' or 'melismatic' rhythm. Finally, according to a brief investigation of the tone organization in accordance with each sutra, the tone 'la' was given more weight. The tone procedure showed a mainly ascending 'la-do'' and the descending 'la-mi' with minor third and perfect fourth. Also, the overall tempo proceeded with M.M.♩.=116-184, while the tempo for the Gut proceeded with M.M.♩.=120-140, which was suitable for reciting a Sutra.