The electric discharge experiment, known as the Miller-Urey experiment, is one of the experiments to understand the origin of life on Earth. The experiment involved simulating the Earth’s early atmosphere by introducing methane(CH4), ammonia(NH3), and nitrogen(N2) gases, and applying energy through electric discharge. Resulting solution was found to contain amino acids such as glycine(C2H5NO2), alanine( C3H7NO2), histidine(C6H9N3O2), proline(C5H9NO2), and valine(C5H11NO2). These amino acids were compared with the results of the recent experiment (Parker et al. 2014). Interestingly, the electric discharge produced C2 swan band and CN emission and it was newly found in gas phase. These two emission bands are commonly observed in comets.

본 연구는 걸밴드 QWER의 사례를 중심으로 K-Pop 걸그룹의 차별화 전 략을 ERRC(Eliminate-Reduce-Raise-Create) 모델을 활용하여 분석하였 다. QWER은 유튜버와 스트리머 출신의 온라인 콘텐츠 크리에이터들로 구 성된 4인조 걸밴드로, 기존과는 차별화된 접근법으로 주목받은 K-Pop 그 룹이다. 질적 연구방법인 내용분석을 통해 QWER의 결성 과정부터 2025년 2월까지의 활동을 분석한 결과, QWER은 ‘제거 전략’으로 전통적인 연습생 시스템, 통일된 이미지와 콘셉트, 기획사 주도의 철저한 관리 시스템에서 탈피했으며, 외모 중심주의, 과밀한 활동량, 과도한 변신에 대한 ‘감소 전 략’을 구사했다. ‘증가 전략’으로는 음악 제작 참여도, 라이브 연주 능력, 맞춤형 팬 소통을 강화했고, ‘창조 전략’으로는 온라인 콘텐츠 크리에이터 기반 발굴 시스템, 하이브리드 계약 모델, 이원화된 기획사 운영 시스템 등 새로운 요소들을 도입했다. 이러한 전략은 K-Pop 산업의 인재 발굴 패러 다임, 계약 및 조직 구조에 변화를 가져옴은 물론, 포화 상태에 이른 K-Pop 시장에서 가치 혁신을 통한 차별화의 중요성을 시사한다.

Background: Prolonged use of computers and mobile devices has contributed to postural abnormalities such as Rounded Shoulder Posture (RSP), which is characterized by muscle imbalances that can lead to pain and functional limitations. Correcting these imbalances through targeted stretching and strengthening exercises was expected to help improve postural alignment and muscle function. Objectives: This study aimed to investigate the effects of a six-week integrated exercise program targeting the pectoralis minor (PM), upper trapezius (UT), and lower trapezius (LT) on postural alignment and muscle activation in female adults with RSP. Design: Single-group pre-post test study. Methods: Eighteen female university students (aged 20–22 years) with RSP participated in a six-week intervention consisting of PM stretching, UT stretching, and LT strengthening exercises. RSP severity was assessed using acromion-to-ground distance, PM length was measured with a caliper, and surface electromyography (sEMG) was used to evaluate UT and LT muscle activity. Normality was verified using the Shapiro-Wilk test, and paired t-tests were conducted for statistical analysis (α=0.05). Results: After the intervention, significant improvements were observed in all measured variables. Acromion-to-ground distance decreased (P<0.001), PM length increased (P<0.001), UT activation decreased (P<0.01), and LT activation increased (P<0.01). Conclusion: The six-week integrated exercise program effectively improved postural alignment and muscle activation in women with RSP by addressing muscle shortening, overactivity, and weakness. These findings suggest that combined stretching and strengthening exercises can serve as a practical and effective approach for RSP correction. Future studies with longer durations and diverse populations are recommended to further validate these results and enhance clinical applicability.

We investigated the effect of band gap engineering on the thermoelectric properties of n-type Cu0.008Bi2Te3 using the two-band (TB) model. The experimental measurements showed a zT of ~0.41 at 300 K and ~0.46 at 520 K, with an optical band gap of ~0.13 eV. While fixing the density-of-state effective mass (md *), deformation potential (Edef), lattice thermal conductivity (κl), and Fermi level based fitted based on experimental data, we varied the band gap (Eg) from 0.1 to 0.3 eV to analyze its impact on the thermoelectric performance. The TB model calculations revealed that the power factor (PF) increased and the thermal conductivity (κ) decreased with increasing Eg at both 300 K and 520 K, leading to an enhancement in zT. The magnitude of this enhancement was more pronounced at 520 K than at 300 K, which can be attributed to the suppressed bipolar effects at higher temperatures. Our findings suggest that increasing the band gap of Cu0.008Bi2Te3 can significantly improve its thermoelectric performance, to an estimated maximum zT of ~0.61 at 520 K for Eg = 0.3 eV. The theoretical maximum zT, considering the optimized hole concentration (nH), was estimated to be ~0.75. We demonstrate that Eg engineering of narrowbandgap semiconductor thermoelectric materials can significantly enhance thermoelectric performance.

Galaxy evolution studies require the measurement of the physical properties of galaxies at different redshifts. In this work, we build supervised machine learning models to predict the redshift and physical properties (gas-phase metallicity, stellar mass, and star formation rate) of star-forming galaxies from the broad-band and medium-band photometry covering optical to near-infrared wavelengths, and present an evaluation of the model performance. Using 55 magnitudes and colors as input features, the optimized model can predict the galaxy redshift with an accuracy of σ(Δz/1+z) = 0.008 for a redshift range of z < 0.4. The gas-phase metallicity [12 + log(O/H)], stellar mass [log(Mstar)], and star formation rate [log(SFR)] can be predicted with the accuracies of σNMAD = 0.081, 0.068, and 0.19 dex, respectively. When magnitude errors are included, the scatter in the predicted values increases, and the range of predicted values decreases, leading to biased predictions. Near-infrared magnitudes and colors (H, K, and H −K), along with optical colors in the blue wavelengths (m425–m450), are found to play important roles in the parameter prediction. Additionally, the number of input features is critical for ensuring good performance of the machine learning model. These results align with the underlying scaling relations between physical parameters for star-forming galaxies, demonstrating the potential of using medium-band surveys to study galaxy scaling relations with large sample of galaxies.

본 연구는 2022년 개정된 문화예술진흥법을 중심으로, 한국의 대중문화 속 서브컬처와 주류 문화의 상호작용에 대해 탐구하였다. 개정된 법은 게임과 애니메이션 등 디지털 콘텐츠를 공식 적으로 문화예술로 인정하며 중요한 전환점을 마련하였다. 이는 서브컬처가 더 이상 하위 집단 에 국한되지 않고 대중문화의 핵심 요소로 부상하고 있음을 보여준다. 큐더블유이알(QWER) 밴드 의 사례는 서브컬처가 주류 문화와 교차하면서 새로운 형태의 대중문화를 창출하는 과정을 상징 적으로 나타낸다. 이 밴드는 인터넷 방송을 통해 자연스럽게 팬덤과의 상호작용을 기반으로 성 장하여, 주류 문화에 흡수되지 않고 독창성을 유지하며 대중적 인정을 받았다. 본 연구는 서브컬 처의 주류화 과정과 그로 인한 사회적, 문화적 영향을 고찰하였으며, 서브컬처가 주류와 상호보 완적인 관계를 형성하면서 문화적 경계를 재구성하는 방식을 분석하였다. 결론적으로, 서브컬처 는 디지털 플랫폼과 팬덤의 참여를 통해 주류 문화와 교차하며 현대 대중문화의 경계를 확장하고 있다. 연구는 서브컬처와 주류 문화 간의 상호작용이 대중문화의 새로운 지평을 여는 데 기여할 수 있음을 시사하며, 디지털 환경에서의 창의적 가능성을 강조한다.

Background: Weakness of gluteus medius (Gmed) is related with musculoskeletal disorders. Individuals who experience weakness in the Gmed may activate the tensor fasciae latae (TFL) as a compensatory mechanism. Application of isometric hip extension (IHE) with Thera-band may affect the activities of the Gmed, gluteus maximus (Gmax), and TFL, and the activity ratio of Gmed/TFL during side-lying hip abduction (SHA). Objects: To determine the influences of IHE during SHA on Gmed, Gmax, and TFL activities in participants with Gmed weakness. Methods: Three types of SHA exercises were performed: 1) traditional SHA in the frontal plane (SHA-T), 2) SHA with IHE applying Thera-band in the frontal plane (SHA-IHE), 3) and SHA with isometric hip flexion (IHF) applying Thera-band in the frontal plane (SHA-IHF). Results: SHA-IHE significantly showed higher Gmed and Gmax activities than SHA-T and SHA-IHF. SHA-IHF significantly showed higher activity of TFL than SHA-T or SHA-IHE. The activity ratio of Gmed/TFL was significantly higher in the SHA-IHE, SHA-T, and SHA-IHF, in that order. Conclusion: The SHA-IHE resulted in higher activities of Gmed, Gmax and a higher muscle ratio of Gmed/TFL.

Background: Balance is the foundation of performing daily activities, and has been proven to be improved by various compression materials. As a new and never-before-seen means, the floss band improves joint range of motion, increases muscle flexibility, and affects balance. Several studies using the short-term application of a floss band to the ankle have been conducted. However, long-term effects of the floss band on the knee warrant further research. Objectives: This study aims to examine the long-term benefits of strength exercises with a floss band applied to the knee for static and dynamic balance. Design: Quasi-experimental design. Methods: A total of 28 participants (four men and 24 women, aged 20–60 years) with no orthopedic knee conditions were recruited and randomized into two groups, with 14 in the group using the strength exercises with floss bands applied to the knee (the floss band group), and 14 in the group using internal rotation of the tibia during mobilization with movements (MWM; the MWM group). A physical therapist with 10 years of clinical experience applied the intervention 10 times, measuring static and dynamic balance before and after the intervention using the Balance Trainer 4. Independent t-tests and paired t-tests were used for statistical analysis, with a significance level of ⍺=.05. Results: Statistically significant effects for static balance and dynamic balance were observed in the comparison from pre- to post-intervention between the floss band and MWM groups (P<.05). Additionally, a statistically significant effect for dynamic balance was noted in the pre- to post-intervention comparison in the floss band group (P<.05). Conclusion: The strength exercises with floss bands applied to the knee are expected to have a long-term effect on improving dynamic balance.

PURPOSES : The tire-pavement interaction noise (TPIN) comprises four sources, among which the tire tread vibration noise (TTVN) and air pumping noise (APN) are known to be the most influential. However, when evaluating TPIN, the noise level is estimated based on the overall noise, because general noise measurement methods cannot separate TTVN and APN. Therefore, this study aims to develop a method to separate TTVN and APN in TPIN for quantitative assessment of pavement noise. METHODS : Based on the results of our literature review and frequency band noise data measured in our study, we identified the dominant frequency ranges for TTVN and APN. Additionally, we evaluated TTVN and APN across various pavement types. RESULTS : TTVN was found to be dominant in frequency bands below 800 Hz, while APN was dominant in frequency bands above 800 Hz. Additionally, regardless of the vehicle type, vehicle speed, or pavement type, APN exhibited higher levels compared to TTVN. This result shows that APN has a more significant impact on TPIN than TTVN. CONCLUSIONS : The separation method of TTVN and APN proposed in this study can be utilized to quantitatively assess the relationship between the primary noise sources in TPIN and the characteristics of pavement texture in future research. Furthermore, it is anticipated that characteristics of low TPIN and optimal texture conditions can be proposed to mitigate TPIN, thus contributing to the development of lownoise pavements.

The n-type Bi2-xSbxTe3 compounds have been of great interest due to its potential to achieve a high thermoelectric performance, comparable to that of p-type Bi2-xSbxTe3. However, a comprehensive understanding on the thermoelectric properties remains lacking. Here, we investigate the thermoelectric transport properties and band characteristics of n-type Bi2-xSbxTe3 (x = 0.1 – 1.1) based on experimental and theoretical considerations. We find that the higher power factor at lower Sb content results from the optimized balance between the density of state effective mass and nondegenerate mobility. Additionally, a higher carrier concentration at lower x suppresses bipolar conduction, thereby reducing thermal conductivity at elevated temperatures. Consequently, the highest zT of ~ 0.5 is observed at 450 K for x = 0.1 and, according to the single parabolic band model, it could be further improved by ~70 % through carrier concentration tuning.

Background: The abdominal drawing-in maneuver (ADIM), a method of lumbar stabilization training, is an effective neuromuscular intervention for lumbar instability associated with low back pain (LBP). Objects: The purpose of this study was to compare the effect of a 2-week period of the ADIM and tensor fasciae latae-iliotibial band (TFL-ITB) self-stretching on lumbopelvic rotation angle, lumbopelvic rotation movement onset, TFL-ITB length, and pain intensity during active prone hip lateral rotation. Methods: Twenty-two subjects with lumbar extension rotation syndrome accompanying shortened TFL-ITB (16 males and 6 females) were recruited for this study. The subjects were instructed how to perform ADIM training or ADIM training plus TFL-ITB self-stretching program at home for a 2-week period. A 3-dimensional ultrasonic motion analysis system was used to measure the lumbopelvic rotation angle and lumbopelvic rotation movement onset. An independent t-test was used to determine between-group differences for each outcome measure (lumbopelvic rotation angle, lumbopelvic rotation movement onset, TFL-ITB length, and pain intensity). Results: The results showed that ADIM training plus TFL-ITB self-stretching decreased the lumbopelvic rotation angle, delayed the lumbopelvic rotation movement onset, and elongated the TFL-ITB significantly more than did ADIM training alone. Pain intensity was lower in the ADIM training plus TFL-ITB self-stretching group than the ADIM training alone group; however, the difference was not significant. Conclusion: ADIM training plus TFL-ITB self-stretching performed for a 2-week period at home may be an effective treatment for modifying lumbopelvic motion and reducing LBP.

필자는 교차편년으로 설정된 기존의 남한 원형점토대토기문화의 연대와 출현 과정에 오류가 있음 을 발견하였다. 이에 방사성탄소연대를 이용해 기존의 견해와 다른 새로운 연대 안과 출현과정을 제 시하고자 하였다. 또한 현재 학계에 뚜렷한 견해가 없는 원형점토대토기문화의 성격에 대하여도 새로 운 시각으로 접근하여 원형점토대토기문화의 실체를 규명하고자 하였다. 그 결과는 다음과 같다. 남한 원형점토대토기는 BC 12세기 무렵, 비파형동검과 동시에 출현하였으며, 이후 후기 청동기시 대 송국리문화, 역삼동후기문화, 검단리문화 등과 기원전 2세기 무렵까지 장기간에 걸쳐 공존하였다. 남한 원형점토대토기문화 집단은 요동지역‘정치집단’의 이주민이 아니라 청동기시대 조기부터 형성 되어 있던‘요동-서북한-남한’의 네트워크를 통해 남한에 들어온‘청동장인집단’이다. 이들이 남겨 놓은 유적 중‘수석리유적’,‘교성리유적’등은 당시 청동의 원광석을 채광·선광했던 장소로 추정 되며,‘동학산유적’,‘방동리유적’등은 청동을 제련·주조 했던 장소로 추정된다. 이‘청동장인집단’은 재지 사회의 지배층에게 비파형동검 등의 청동기를 제작·공급해서 생계를 유지하던 기술장인들이었으나 점차 정치력을 갖게 되면서 세형동검단계에 이르러서는 당시 사회의 지 배층인‘제사장’이되고, 결국 삼한 사회의 최상위 지배층으로 성장한다.

The main goal of the Korean VLBI Network Calibrator Survey (KVNCS) is to expand the VLBI calibrators catalog for KVN, KaVA(KVN and VERA Array), EAVN(East-Asian VLBINetwork), and other extended regions. The secondKVNCS (KVNCS2) aimed to detect VLBI fringes of new candidates for calibrators in the K band. Out of the 1533 sources whose single-dish flux density in the K band was measured with KVN telescopes (Lee et al. 2017), 556 sources were observed with KVN in the K band. KVNCS2 confirmed the detection of VLBI fringes of 424 calibrator candidates over a single baseline. All detected sources had a high Signal-to-Noise Ratio (SNR) of >25. Finally, KVNCS2 confirmed 347 new candidates as VLBI calibrators in the K band, resulting in a 5% increase in the sky coverage compared to previous studies. The spatial distribution was quasi-uniform across the observable region (Dec. > −32.5◦). In addition, the possibility as calibrator candidates for the detected sources was checked, using an analysis of the flux-flux relationship. Ultimately, the KVNCS catalog will not only become the VLBI calibrator list but is also useful as a database of compact radio sources for astronomical studies.