• Proceedings of the KIPE Conference
• /
• 2001.07a
• /
• pp.118-123
• /
• 2001

For multi-carrier communication system, power amplifier generate intermodulation products caused by their nonlinear characteristics. Intermodulation products arised around the carrier frequency cannot be filtered out, operate as noise source for tile adjacent channel and thus degrades the quality of communication. In this paper, the 1850MHz-band RF linear power amplifier has been designed and fabricated with feedforward loop. The error signal loop consists of several key components such as phase shifter and attenuator, subtracter. The proposed Linearizer was tested with two-tone signals separated 10MHz apart at the center frequency of 1850MHz. The experimental results show C/I improvement by 14.5${\~}$20dB over 15dB dynamic range(33${\~}$47.8dBm) which gave IMD of 53.25${\~}$59dBc for the designed LPA.

• Korean Journal of Culture and Social Issue
• /
• v.27 no.2
• /
• pp.167-189
• /
• 2021

The purpose of this study was to classify different profiles of grit (effort vs. interest) and passion mindset (fixed vs. growth) in university students and to understand whether there are differences in psychological characteristics (ie. depression, anxiety and happiness) and career adaptability between the profiles. To this end, we recruited 359 students aged 18 and 25 and applied a Latent Profile Analysis(LPA). The results revealed 4 distinct profiles : Profile1-a burgeoning type, Profile2-an ordinary type, Profile3-a fixed/limited type, Profile4-sprouting/drifting type. The profile1(LP1, 22.2%) had high levels of grit and passion growth mindset. The profile2(LP2, 63.8%) showed average levels in both grit and passion mindset. The profile3(LP3, 8.8%) had a low level of grit and a high level of passion fixed mindset. The profile4(LP4, 5.1%) showed a low level of grit and a high level of passion growth mindset. The four profiles were distinct in psychological characteristics and career adaptability. The burgeoning type(profile1) was most adaptive in comparison to the fixed/limited type(profile 3). These results suggest that grit has more powerful effects on psychological characteristics while passion growth mindset exerts stronger influencers in career adaptability. Putting the results together, our findings imply that both passion growth mindset and grit need to be considered together to enhance the individuals' comprehensive well-being and to increase the level of adaptation for career preparation.

• Journal of Chest Surgery
• /
• v.17 no.1
• /
• pp.32-40
• /
• 1984

During the past six years from July 1977 to June 1983, fifteen adult patients of patent ductus arteriosus were surgically treated. The results were as follows: 1. Of the 15 patients, their age range was 17 to 34 years with a mean of 24 years, and sexual predominance was women [9. cf. 6 men]. 2. The most common symptom showed exertional dyspnea, and 10 patients were classed in NYHA class II, the rest were all class III. 3. On physical examination, all patients were auscultated continuous murmur, but concomitantly diastolic murmur was noted apical region in 2 patients. 4. On roentgenogram of chest, normal finding was 3 patients, and the other patients were revealed the evidence of pulmonary congestion. 5. The electrocardiogram was normal in 6 patients, but LVH was seen in 5, and 2 patients were LVH+ LAH. 6. Cardiac catheterization was performed in 12, and mean value of SO2[LPA-RV] was 6.3%, Q/Q 2.09, peak systolic pulmonary arterial pressure 45.3 mmHg, and Rp/Rs 0.365. 7. All operations were carried out by posterolateral thoracotomy. In 6 patients, division and suture of ductus were possible, the other patients were treated by division and ligation with heavy silk or Dacron patch. 8. Postoperative complications were hoarseness, persistent murmur, reoperation for bleeding, and atelectasis. Early and late mortality was 20% [3 patients], and cause of death was mainly aneurysmal rupture of previous operative site.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.16 no.2
• /
• pp.69-76
• /
• 1980

This paper describes the measurement of the underwater noises produced by the engine vibration around the engine room of stern trawler MIS Sae-Ba-Da(2275GT, 3,600 PS) and pole kner M/S Kwan-Ak-San (243 GT, 1000 PS) while the ship is stopping. The underwater noise pressure level was measured with the underwater level meter of which measuring range is 100 to 200 dB(re bLPa). A and B denotes the maximum pressure level measured at right beneath the bottom of the engine room, while the main engine of the Sae-Ba-Da revoluted at 750 and 500 rpm, respectively. C denotes that of the main engine of the Kwan-Ak-San revoluted at 350 rpm, and D that of the generator of the Sae-Ba-Da revoluted at 720 rpm. Thus A, B, C and D were set for the standard sound source for the experiment. The results obtained are as follows: 1. The noise Pressure level at A, B, C and D were 170.5,165,153 and 158dB, respectively. 2. When the check points distanted vertically 1, 10, 20, 30, 40, 50m from the sound source, the underwater noise presure levels were 170.5, 155, 148, 144 and 138 dB and the directional angle was 116\ulcorner in case of A. 3. The sound level attenuated at the rate of 20dB per 10" meters of the horizontal distance from the sound sources. 4. The frequency distribution of the noise was 100Hz to 10KHz and predominant frequency was 700 to 800Hzminant frequency was 700 to 800Hz

• 한국노년학
• /
• v.36 no.3
• /
• pp.765-783
• /
• 2016

This study examines 2014 National Survey on Older Koreans (10,279 persons aged 65 or above) to understand social networks among older Koreans. In order to classify the types of social relationships, the latent profile analysis is conducted based on such structural aspects of social networks as network size, frequencies of contact, and closeness. The results show that older Koreans can be categorized into 5 distinct social network types: disengaged (11.6%), ritual-family-focused (17.7%), close-family-focused (23.6%), close-restricted (28,4%), and diverse (18.8%). Characteristics by each social network type are compared and multinominal logistic regression analyses are applied to figure out the influencing factors of social network type. Older persons with disengaged social network ties tend to be overwhelmingly female, living alone, old-old, and of low socioeconomic status. On the other hand, older persons with diverse social network ties tend to be young-old and had highly-ranked jobs in their mid-life. Spouse/children are the focal point of social relationships in both ritual-family-focused and close-restricted social network. However, the proportion of men is higher in the close-family-focused type than in the ritual-family-focused. Older Koreans with close-restricted social network ties tend to be female, uneducated, and have engaged in agricultural and allied activities. This study discusses the implications of its findings and how research in this area should develop in the future.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.6
• /
• pp.899-910
• /
• 2023

The majority of research on lifestyle has been conducted based on a variable-centered approach. However, over the last decades, there is a growing body of research on lifestyle in terms of a person-centered approach. Hence, this study identifies senior generations' profiles based on the combination of the five realms of lifestyle. More specifically, this study utilized a Latent profile analysis(LPA) to explore both quantitatively and qualitatively distinct types of senior generation' lifestyle profiles. As a result, the five distinct types of senior lifestyle profiles were identified and these five profiles were then contrasted with traveling attitude and behavioral intention(traveling intention). In addition, this study attempted to identify similarity in the patterns of relations with theoretical antecedent, correlate and outcome variables. Results showed that even though senior generation belonging to profile groups pertaining to the high level of all five types of lifestyle were associated with a high level of attitude and behavior intention, there was no differences among the profiles. This means that regardless of the patterns of senor generation lifestyle profiles, there was no similarity. Nevertheless, it should be considered that senior generation consider a security when making a travel ling decision regardless of the patterns of lifestyle profiles. This results suggest that senior generation' traveling satisfaction is more likely obtained with the experience of safety and convenience during their travel. At last, this study discusses some implication tourism theory related to lifestyle, practices and future research on tourism profiles.

• Journal of Chest Surgery
• /
• v.21 no.1
• /
• pp.10-16
• /
• 1988

Ten patients with tetralogy of Fallot were studied angiocardiographically before a modified Blalock-Taussig shunt and again 25*3.2 months after the previous shunt. All of ten patients had patent previous shunt at the time of follow up examination. Pre-and postoperative diameters of left and right pulmonary artery and descending aorta were measured and pulmonary artery index [the sum of the crossectional areas of the right and left pulmonary arteries standardized by the body surface area] was calculated. The ratio of mean diameter of left and right pulmonary arteries to the diameter of the descending aorta [LPA+RPA/2xDA] was increased postoperatively by 0.20*0.068 [p=0.020]. Mean PAI [pulmonary artery index] increased from 283.8*178.4 mm/m2 BSA to 345.8~144.5 mm/m2 BSA after shunt operation [p=0.019]. This results suggested that the modified Blalock-Taussig shunt was effective to help growth of the pulmonary arteries in most cases of the study populations but the ones with the PAI>233mm*/m* BSA appeared less benefited by Blalock Taussig shunt. Calculation of PAI could be an aid to making a decision whether to perform a one stage corrective surgical procedure or a palliative shunt procedure in the patient with small pulmonary arteries.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.2
• /
• pp.75-82
• /
• 2000

In this Paper, a new type of feedforward linearizer using a delay line which controls the phase characteristics of the correction amplifier block is proposed. The extra delay line provides the control-ability of IM signals so that the IM rejection is accomplished without the conventional pilot tone. The error signal loop consists of several key components such as phase shifter and attenuator, subtractor. These key components are replaced by new designs in order to obtain better linearization characteristics without the pilot tone generator which is indispensable in the conventional linearizer designs. The proposed linearizer was designed at Korean PCS band and combined with 35W HPA manufactured by KMW inc., and tested with two-tone signals separated 0.6MHz apart at the center frequency of 1855MHz. The experimental results show C/l improvement by 16.9 ~ 24.6 dB over 15 dB dynamic range(30 ~45 dBm) which gave IMD of 58.5~63.2 dBc for the designed LPA.

• The Journal of the Korea Contents Association
• /
• v.21 no.7
• /
• pp.533-545
• /
• 2021

This study aimed to examine the differences in gender equality consciousness between latent profiles based on corporate workers' organizational culture types. To achieve the study's purpose, descriptive statistics, correlation analysis, and latent profile analysis (LPA) were conducted using 253 Korean corporate workers' data. As a result of the analysis, the latent profiles of organizational culture recognized by corporate workers were classified into 5 profiles. We named each profile as high compete-low create culture, high compete-low collaborate culture, collaborate culture, high create culture, and high control culture based on each profile's organizational culture perception. The ANOVA test found statistically significant differences between the groups in the gender equality consciousness. This study is meaningful in that it reveals the relationship between the organization culture perception and the gender equality consciousness and suggested implications for the organizational-level intervention to improve the gender equality consciousness. It will provide basic data for your research.

• BMB Reports
• /
• v.39 no.5
• /
• pp.626-635
• /
• 2006

Lysophosphatidic acid acyltransferase (LPAAT) is an intrinsic membrane protein that catalyzes the synthesis of phosphatidic acid (PA) from lysophosphatidic acid (LPA). It is well known that LPAAT is involved in lipid biosynthesis, while its role in tumour progression has been of emerging interest in the last few years. To date, seven members of the LPAAT gene family have been found in human. Here we report a novel LPAAT member, designated as LPAAT-theta, which was 2728 base pairs in length and contained an open reading frame (ORF) encoding 434 amino acids. The LPAAT-theta gene consisted of 12 exons and 11 introns, and mapped to chromosome 4q21.23. LPAAT-theta was ubiquitously expressed in 18 human tissues by RT-PCR analysis. Subcellular localization of LPAAT-theta-EGFP fusion protein revealed that LPAAT-theta was distributed primarily in the endoplasmic reticulum (ER) of COS-7 cells. Furthermore, we found that the overexpression of LPAAT-theta can induce mTOR-dependent p70S6K phosphorylation on Thr389 and 4EBP1 phosphorylation on Ser65 in HEK293T cells.